The present application relates generally to transmission hydraulic control units and, more particularly, to systems for retaining valves and springs in an additive manufactured valve body for a hydraulic control unit.
Modern vehicle transmissions typically include a hydraulic control unit to control hydraulic pressure and direct hydraulic fluid within hydraulic passages to control one or more components of the transmission. Some typical configurations include multiple layers of cast bodies divided by separator plates and all clamped together with many fasteners. This can potentially lead to leakage at the interface between the valve body and separator plates. Due to the nature of the casting process by which these parts are made, the minimum size of the hydraulic passages is typically in excess of the requirement, thereby potentially adding unnecessary mass to the system. Thus, while such conventional systems work well for their intended purpose, there remains a desire for improvement in the relevant art.
According to one example aspect of the invention, an additive manufactured (AM) hydraulic control assembly is provided. In one example configuration, the assembly includes an AM housing having a tubular wall defining a bore configured to receive at least one of a hydraulic valve and an accumulator, and a retainer clip configured to selectively secure to the AM housing such that the retainer clip is movable between a secured position that extends across at least a portion of the bore to retain the hydraulic valve or accumulator within the AM housing, and an unsecured position that enables the hydraulic valve or accumulator to be inserted into or removed from the bore.
In addition to the foregoing, the described assembly may include one or more of the following features: an AM hydraulic passage having a second tubular wall defining a fluid passage, wherein the AM hydraulic passage is fluidly coupled to the bore; wherein the at least one of a hydraulic valve and an accumulator comprises an accumulator having a plunger and a biasing mechanism; wherein the AM housing includes a slot formed through the tubular wall, and wherein the retainer clip includes an intermediate arm configured to be received within the slot when in the secured position; and wherein the intermediate arm is coupled to a main body between a pair of opposed arms configured to clip to the AM housing.
In addition to the foregoing, the described assembly may include one or more of the following features: wherein the retainer clip is an AM retainer clip formed with the AM housing; wherein the retainer clip includes a retainer body disposed between an attaching end configured to attach the retainer clip to the AM housing, and a securing end configured to selectively secure the retainer clip to the AM housing when in the secured position; wherein the attaching end is hingedly coupled to the AM valve housing, and the securing end includes a detent configured to engage a projection formed on the AM valve housing when in the secured position; wherein the attaching end includes a pair of knuckles additively manufactured with a clearance between the pair of knuckles and a pin formed on the AM housing; and wherein the attaching end includes a pin with opposed ends having detents formed therein, the detents configured to receive opposed projections extending from opposed support members integrally formed with the AM housing.
In addition to the foregoing, the described assembly may include one or more of the following features: wherein the tubular wall includes an end face with at least one recess formed therein, and wherein when in the secured position, the retainer clip is constrained within the recess from transverse movement to facilitate preventing detachment of the securing end from the AM housing; wherein the at least one of a hydraulic valve and an accumulator comprises a hydraulic valve having a biasing mechanism and a seal coupled to a valve stem; and wherein the securing end is hook-shaped and configured to receive a tab integrally formed with and extending outwardly from the AM housing tubular wall; and wherein the securing end includes a transverse member defining opposed tabs configured to engage a pair of outer tabs integrally formed with and extending outwardly from the AM housing tubular wall.
Further areas of applicability of the teachings of the present application will become apparent from the detailed description, claims and the drawings provided hereinafter, wherein like reference numerals refer to like features throughout the several views of the drawings. It should be understood that the detailed description, including disclosed embodiments and drawings references therein, are merely exemplary in nature intended for purposes of illustration only and are not intended to limit the scope of the present application, its application or uses. Thus, variations that do not depart from the gist of the present application are intended to be within the scope of the present application.
The present application is directed to a transmission hydraulic control unit having one or more additive manufactured (AM) features such as, for example, hydraulic valve housings, accumulator housings, and retainer clips therefor. The AM hydraulic valve housing includes a bore configured to receive a hydraulic valve, and the retainer clip is coupled to the valve housing to retain the hydraulic valve in the bore. Similarly, the AM accumulator housing includes a bore configured to receive an accumulator, and the retainer clip is coupled to the accumulator housing to retain the accumulator in the bore. In some examples, the retainer clip is formed during the additive manufacturing process of the valve housing or accumulator housing.
In one example, a slot is formed through the housing wall perpendicular to the axis of the bore. A middle leg of a three-legged retaining clip is then inserted into the slot. The two outside legs of the clip are formed to snap over the round exterior wall of the housing to thereby secure the retainer clip to the housing. The force of the valve and spring forces the retainer clip against the end of the slot.
In another example, using additive manufacturing processes, a retainer clip is permanently attached to the end of the housing. A hinge connects the end of the bore and the edge of the retaining clip. A clearance is formed between the AM retaining clip and hinge such that the retaining clip moves freely and is permanently assembled thereto. The retainer clip can rotate about the hinge to enable insertion or removal of the valve or accumulator. The retainer clip includes a ramp or detent that snaps over a raised portion of the housing such that the retainer is latched in place to facilitate preventing the force of the hydraulic control valve and spring from unlatching it.
In yet another example, the retainer clip is formed with a hook-type feature at one end and a detent with a latching feature at the other end. A tab formed on the AM housing receives the hook, and a raised surface projection on the AM housing receives the latching feature and is inverse thereto. The raised surface allows the retainer to slide over the surface and latch into place. Edges of the housing extend beyond the clip to prevent the clip from slipping off.
In another example, the retainer clip is T-shaped and includes a ramp with a latching feature. The retainer clip is secured between a pair of projections formed on the AM housing. The projections extend away from the bore face to enable the retainer to be positioned vertically with one face mated to the bore face and the other mated to the projections such that the retainer is constrained along the axis of the bore. A raised surface formed on the AM housing is the inverse of a distal portion of the retainer clip and allows the retainer to slide over the raised surface and latch into place thereon to facilitate preventing valve/spring forces from unlatching.
Referring now to the drawings,
With reference to
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With reference to
In the example embodiment, the retainer clip 138 generally includes a retainer body 148 disposed between an attaching end 150 and a securing end 152. The attaching end 150 includes a support member 154 having a pair of knuckles 156 each defining an aperture 158 for receiving the pin 140. During the additive manufacturing process, the attaching end 150 is formed with a clearance between the knuckles 156 and the pin 140, thereby providing a hinged coupling between the retainer clip 138 and the pin 140. As shown in
With reference now to
In the example embodiment, the AM valve housing 170 is integrally formed with an AM retainer assembly 178, which includes a retainer mechanism or clip 180 hingedly coupled between a pair of support members 182. As shown in
In the example embodiment, the retainer clip 180 generally includes a retainer body 186 disposed between an attaching end 188 and a securing end 190. The attaching end 188 includes a pin 192 having opposed ends 194 with detents 196. As shown in
As shown in
With reference now to
In the example embodiment, the attaching end 230 is generally hook-shaped and is configured to receive a tab 234 extending outwardly from an outer surface of the tubular wall 222, as shown in
With reference now to
In the example embodiment, the attaching end 260 is a generally transverse member or bar 264 defining opposed tabs 266 with an inner surface 268. As shown in
Further, in the example embodiment, the outer surface of the tubular wall 222 is also formed with a raised projection 274. The retainer clip securing end 262 includes a detent 276 sized and shaped to interferingly engage the projection 274 when the retainer clip 256 is moved to a closed position (FIGS.13-16), such that retainer body 258 extends across the opening of valve bore 254 and facilitates retaining the hydraulic valve assembly within the valve bore 254.
Additionally, in this position, as shown in
Described herein are systems and methods for an additive manufactured hydraulic valve body. Various features are formed in the additive manufactured valve body that otherwise could not be formed using conventional casting processes. The features include additive manufactured valve and accumulator housings integrated into the overall additive manufactured valve body and configured to have or receive retainer clips to retain valve or accumulator components within the housings. In this way, typically separate components are integrated into a single component, which drastically reduces the number of required fasteners and overall mass of the system.
It will be understood that the mixing and matching of features, elements, methodologies, systems and/or functions between various examples may be expressly contemplated herein so that one skilled in the art will appreciate from the present teachings that features, elements, systems and/or functions of one example may be incorporated into another example as appropriate, unless described otherwise above. It will also be understood that the description, including disclosed examples and drawings, is merely exemplary in nature intended for purposes of illustration only and is not intended to limit the scope of the present application, its application or uses. Thus, variations that do not depart from the gist of the present application are intended to be within the scope of the present application.