Quick disconnect coupling with internal valves

A quick disconnect coupling can include a first part and a second part. The first part can define a primary fluid passageway and a secondary fluid passageway and can include a first valve movable between open and closed positions to control flow through the first part secondary fluid passageway. The second part can define a second part defining a primary fluid passageway and a secondary fluid passageway and can include a second valve movable between open and closed positions to control flow through the second part secondary fluid passageway. In one aspect, the second part is removably connectable to the first part such that, when connected the first and second part primary passageways are placed in fluid communication with each other and the first and second valves are operable between the open and closed positions to selectively place the secondary fluid passageways of the first and second parts in fluid communication with each other.

BACKGROUND

Line replaceable units (LRU's) are commonly used in fluid conveyance systems (e.g. hydraulic and coolant systems) where a system or subsystem must be readily replaceable. In a typical configuration, the hydraulic system connected to the LRU must be drained before the LRU can be disconnected and can only be refilled after a new LRU has been installed. Once the system has been re-filled the system must also be bled of air. Such processes are labor and time intensive. Improvements are desired.

SUMMARY

A quick disconnect coupling can include a first part and a second part. The first part can define a primary fluid passageway and a secondary fluid passageway, and can include a first valve movable between open and closed positions to control flow through the first part secondary fluid passageway. The second part can define a primary fluid passageway and a secondary fluid passageway and can include a second valve movable between open and closed positions to control flow through the second part secondary fluid passageway. In one aspect, the second part is removably connectable to the first part such that, when connected the first and second part primary passageways are placed in fluid communication with each other, and the first and second valves are operable to place the secondary fluid passageways of the first and second parts in fluid communication with each other.

A quick disconnect coupling can include a first part defining a primary fluid passageway and a secondary fluid passageway, and can include a first valve movable between open and closed positions to control flow through the first part secondary fluid passageway and a primary valve movable between open and closed positions to control flow through the first part primary passageway. The quick disconnect coupling can also include a second part defining a primary fluid passageway and a secondary fluid passageway, and can include a second valve movable between open and closed positions to control flow through the second part secondary fluid passageway and a primary valve movable between open and closed positions to control flow through the second part primary passageway. In one aspect, the second part is removably connectable to the first part such that, when connected, the first and second part primary valves are open to place the primary passageways of the first and second parts in fluid communication with each other and the first and second valves are operable to place the secondary fluid passageways of the first and second parts in fluid communication with each other.

In some examples, one or both of the first and second valves allow fluid flow in a first direction and prevent fluid flow in a second direction.

In some examples, one or both of the first and second valves is a check valve.

In some examples, the first valve is a relief valve and the second valve is a check valve.

In some examples, the second valve is a bleed-check valve.

In some examples, the first and second valves are biased towards a closed position.

In some examples, the first and second valves are biased in the same direction.

In some examples, the first valve and the second valve abut each other when the first and second parts are connected to each other.

In some examples, fluid flow from the first part secondary fluid passageway to the second part secondary fluid passageway is prevented when either of the first and second valves is in the closed position.

In some examples, the first valve is moved from the closed position towards the open position by fluid pressure.

In some examples, the second valve is moved from the closed position towards the open position by the first valve or by fluid pressure.

In some examples, the secondary fluid passageways of the first and second parts are coaxial with the primary fluid passageways of the first and second parts.

In some examples, the secondary fluid passageways of the first and second parts are surrounded by the primary fluid passageways of the first and second parts.

A quick disconnect coupling can include a first part defining a primary fluid passageway and a secondary fluid passageway, the first part including a relief valve controlling flow through the secondary fluid passageway; and a second part defining a primary fluid passageway and a secondary fluid passageway, the second part including a check valve controlling flow through the secondary fluid passageway, the second part being removably connectable to the first part such that, when connected, the relief and check valves are operable to allow for fluid flow from the first part secondary fluid passageway into the second part secondary fluid passageway.

In some examples, the relief and check valves allow fluid flow in a first direction and prevent fluid flow in a second direction.

In some examples, the relief and check valves are biased towards a closed position.

In some examples, the relief and check valves abut each other when the first and second parts are connected to each other.

In some examples, fluid flow from the first part secondary fluid passageway to the second part secondary fluid passageway is prevented when either of the relief and check valves is in the closed position.

In some examples, the relief valve is moved from the closed position towards the open position by fluid pressure.

In some examples, the check valve is moved from the closed position towards the open position by the relief valve or by fluid pressure.

In some examples, the secondary fluid passageways of the first and second parts are coaxial with the primary fluid passageways of the first and second parts.

In some examples, the secondary fluid passageways of the first and second parts are surrounded by the primary fluid passageways of the first and second parts.

A quick disconnect coupling can include a first part defining a primary fluid passageway and a secondary fluid passageway, the first part including first and second valve structures movable between open and closed positions to control flow through the first part secondary fluid passageway; and a second part defining a primary fluid passageway and a secondary fluid passageway, the second part including a third and fourth valve structures movable between open and closed positions to control flow through the second part secondary fluid passageway; wherein the second part is removably connectable to the first part such that, when connected: the first and second part primary passageways are placed in fluid communication with each other; and the first and third valves are placed in an open position and the second and fourth valves are biased towards a closed position.

In some examples, one or more of the first through fourth valves allow fluid flow in a first direction and prevent fluid flow in a second direction.

In some examples, the first and third valves are check valves.

In some examples, the second and fourth valves are relief valves and the first and third valves are check valves.

In some examples, the first and third valves are biased towards a closed position.

In some examples, the third valve is concentrically arranged within the first valve and wherein the fourth valve is concentrically arranged within the second valve.

In some examples, the second valve and the third valve abut each other when the first and second parts are connected to each other.

In some examples, fluid flow from the first part secondary fluid passageway to the second part secondary fluid passageway is prevented when either of the first and third valves is in the closed position.

In some examples, the second and fourth valves are moved from the closed position towards the open position by fluid pressure.

In some examples, the second valve is moved from the closed position towards the open position by the fourth valve.

In some examples, the secondary fluid passageways of the first and second parts are coaxial with the primary fluid passageways of the first and second parts.

In some examples, the secondary fluid passageways of the first and second parts are surrounded by the primary fluid passageways of the first and second parts.

A quick disconnect coupling can include a first part defining a primary fluid passageway and a secondary fluid passageway, the first part including first and second valves movable between open and closed positions to control flow through the first part secondary fluid passageway, a primary valve movable between open and closed positions to control flow through the first part primary passageway, a second part defining a primary fluid passageway and a secondary fluid passageway, the second part including third and fourth valves movable between open and closed positions to control flow through the second part secondary fluid passageway, a primary valve movable between open and closed positions to control flow through the second part primary passageway, wherein the second part is removably connectable to the first part such that, when connected: the first and second part primary valves are open to place the primary passageways of the first and second parts in fluid communication with each other and the first through fourth valves are operable to place the secondary fluid passageways of the first and second parts in fluid communication with each other.

In some examples, one or both of the first through fourth valves allow fluid flow in a first direction and prevent fluid flow in a second direction.

In some examples, one or both of the first and third valves is a check valve.

In some examples, the first and third valves are check valves and the second and fourth valves are relief valves.

In some examples, the first through fourth valves are biased towards a closed position.

In some examples, the third valve is concentrically arranged within the first valve and wherein the fourth valve is concentrically arranged within the second valve.

In some examples, the second valve and the fourth valve abut each other when the first and second parts are connected to each other.

In some examples, fluid flow from the first part secondary fluid passageway to the second part secondary fluid passageway is prevented when either of the first and third valves is in the closed position.

In some examples, the second and fourth valves are moved from the closed position towards the open position by fluid pressure.

In some examples, the first and third valves are respectively moved from the closed position towards the open position by the second and fourth valves.

In some examples, the secondary fluid passageways of the first and second parts are coaxial with the primary fluid passageways of the first and second parts.

In some examples, the secondary fluid passageways of the first and second parts are surrounded by the primary fluid passageways of the first and second parts.

A first coupling part of a quick disconnect coupling arrangement can include a primary fluid passageway, a secondary fluid passageway in fluid communication with the primary fluid passageway, a primary valve for controlling flow through the primary fluid passageway, a check valve for controlling flow through the secondary fluid passageway, a relief valve for controlling flow through the secondary fluid passageway, wherein the primary valve, check valve, and relief valve are concentrically aligned along a common axis.

In some examples, the relief valve is at least partially housed within the check valve.

In some examples, the check valve allows fluid flow in a first direction and prevents fluid flow in a second direction.

In some examples, the relief and check valves are biased towards a closed position.

In some examples, the check valve can be moved from the closed position towards the open position by an opposing force exerted on a head portion of the relief valve. In some examples, the secondary fluid passageway is surrounded by the primary fluid passageway.

A quick disconnect coupling can include a first part and a second part. The first part can define a primary fluid passageway and a secondary fluid passageway, the first part including a first valve configured as a relief or check valve controlling flow through the secondary fluid passageway. The second part can define a primary fluid passageway and a secondary fluid passageway, the second part including a second valve configured as a relief or check valve controlling flow through the secondary fluid passageway. The second part is removably connectable to the first part such that, when connected, the first and second valves are operable to allow for fluid flow from the first part secondary fluid passageway into the second part secondary fluid passageway.

In some examples, the first valve is configured as a relief valve that is moved from the closed position towards the open position by fluid pressure.

In some examples, the second valve is configured as a check valve that is moved from the closed position towards the open position by the relief valve or by fluid pressure.

A quick disconnect coupling arrangement can include a primary fluid passageway, a secondary fluid passageway in fluid communication with the primary fluid passageway, a primary valve for controlling flow through the primary fluid passageway, a poppet valve for controlling flow through the secondary fluid passageway, and a relief valve for controlling flow through the secondary fluid passageway when first and second part are in the disconnected position only, wherein the primary valve, poppet valve, and relief valve are concentrically aligned along a common axis.

In some examples, the relief valve is at least partially housed within the poppet valve.

In some examples, the poppet valve allows fluid flow in both directions.

In some examples, the relief and poppet valves are biased towards a closed position.

In some examples, the poppet valves are moved from the closed position towards the open position by the opposing poppet valve when first coupling part is connected with second coupling part.

In some examples, the secondary fluid passageway is surrounded by the primary fluid passageway.

A quick disconnect coupling can include a first part defining a primary fluid passageway and a secondary fluid passageway, the first part including first and second valve structures movable between open and closed positions to control flow through the first part secondary fluid passageway and a second part defining a primary fluid passageway and a secondary fluid passageway, the second part including a third and fourth valve structures movable between open and closed positions to control flow through the second part secondary fluid passageway, wherein the second part is removably connectable to the first part such that, when connected the first and second part primary passageways are placed in fluid communication with each other, and the first and third valves are placed in an open position and the second and fourth valves are biased towards a closed position.

In some examples, one or both of the first and third valves allow fluid flow in both directions.

In some examples, the first and third valves are poppet valves.

In some examples, the second and fourth valves are relief valves and the first and third valves are poppet valves.

In some examples, the first and third valves are biased towards an open position when coupling first and second parts are connected.

In some examples, the third valve is concentrically arranged within the first valve and wherein the fourth valve is concentrically arranged within the second valve.

In some examples, the second valve and the third fourth valve abut each other when the first and second parts are connected to each other.

In some examples, fluid flow from the first part secondary fluid passageway to the second part secondary fluid passageway is opened when the first and second coupling parts are connected.

In some examples, the second and fourth valves are moved from the closed position towards the open position by fluid pressure when first and second coupling parts are in the disconnected position.

In some examples, the secondary fluid passageways of the first and second parts are coaxial with the primary fluid passageways of the first and second parts.

In some examples, the secondary fluid passageways of the first and second parts are surrounded by the primary fluid passageways of the first and second parts.

A variety of additional aspects will be set forth in the description that follows. The aspects can relate to individual features and to combinations of features. It is to be understood that both the forgoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the broad inventive concepts upon which the examples disclosed herein are based.

DETAILED DESCRIPTION

Various examples will be described in detail with reference to the drawings, wherein like reference numerals represent like parts and assemblies throughout the several views. Reference to various examples does not limit the scope of the claims attached hereto. Additionally, any examples set forth in this specification are not intended to be limiting and merely set forth some of the many possible examples for the appended claims. Referring to the drawings wherein like reference numbers correspond to like or similar components throughout the several figures.

Referring toFIGS. 1 to 4 and 10 to 13, a quick disconnect coupling100is presented. The quick disconnect coupling100includes a first part200and a second part300that can be connected and disconnected from each other relatively quickly and without the use of tools. For the purpose of clarity, the first part200is shown in isolation atFIGS. 6 and 7and the second part300is shown in isolation atFIGS. 8 and 9.

With reference toFIGS. 6 and 7, the first part200includes a main body202extending between a first end202aand a second end202b. The main body202further defines an internal fluid passageway202cextending between the first and second ends202a,202b. The main body202is further shown as defining a fitting202dproximate the first end202awhereby a threaded or non-threaded pipe, tube, hose, or manifold port can be connected to the first part. The main body202is further shown as being provided with a first collar portion202ewhich can serve as an interface for a tool, such as a wrench, for installing the main body202onto the pipe, tube, manifold port or hose and/or for holding the first part200stable while the second part300is being installed or removed from the first part200. The main body202is also shown as including a threaded connection202fproximate the second end202bfor receiving a threaded portion306dof the second part300such that the first and second parts200,300can be connected together. The main body202is further shown as including a second collar202ghaving one or more notches202h. A sleeve322of the second part300can abut the second collar202gand tab portion(s)322bof the sleeve can be received into the one or more notches202hsuch that the second part300cannot be unthreaded from the first part200until the sleeve has been retracted sufficiently to disengage the tab portion(s)322bfrom the one or more notches202h. The main body200is also shown as including a seal channel or recess202i, a stop surface202j, and a shoulder202k, each of which is discussed in further detail below.

With continued reference toFIGS. 6 and 7, the first part200is further shown as including a valve structure204including a first valve part206and a second valve part208. In one aspect, the valve structure204can be characterized as a primary internal valve structure204. The first valve part206is shown as having a main body206awith a base portion202bhaving apertures202c, wherein the base portion206bis supported by the shoulder202k. The main body206ais further shown as including a stem portion206dhaving apertures206e. The stem portion206dis configured as a hollow cylindrical member extending from the base portion206b. The second valve part208is shown as having a main body208awith a base portion208band a stem portion208cextending from the base portion208b. The stem portion208cis configured as a hollow cylindrical member extending from the base portion208band is sized to be slidably received into the stem portion206dof the first valve part206. A collar210is also shown as being connected to the base portion208band includes a central aperture210areceiving the stem portions206d,208band a plurality of radial apertures210b. In the example shown, the collar210is snap-fit into a recess208dof the main body208. The valve structure204is also shown as including a biasing spring212extending between the first and second valve parts206,208. The biasing spring212forces the second valve part208towards the second end202binto a closed position, which is the position shown atFIG. 7.

In the closed position of the valve structure204, seal member214, located in recess202i, forms a seal against the second valve part208such that fluid flow through the internal passageway202cis blocked by the second valve part208. A backup ring216is also provided in the recess202ito support the seal member214. The second valve part208is stopped by the interaction between the collar210and the stop surface202jof the main body202. It is noted that the initial movement of the second valve part208from the position shown atFIG. 7towards the second end202adoes not unblock the fluid passageway202c, and that the second valve part208must be displaced towards first end202asuch that a front face portion208fis moved proximate the stop surface202j.

In one aspect, the stem portions206dand208cdefine a secondary fluid passageway218and further define a valve structure220. When the valve structure220is in the closed position, the stem portion208cis moved relative the stem portion206dsuch that the apertures206eare open to the internal fluid passageway202c, thereby providing an alternative or secondary pathway for placing the secondary fluid passageway218in fluid communication with the internal fluid passageway202c. When the valve structure204is moved into an open position, such as shown inFIGS. 10 to 13, the stem portion208cslides further into the stem portion206dand blocks the apertures206e. Regardless of the position of the stem portion208c, a fluid pathway between the passageways202c,218exists proximate the first end202awhereby fluid can flow into either passageway. Accordingly, in some embodiments, the apertures206ecan be eliminated without departing from the concepts presented herein.

In one aspect, the first valve part200further includes a valve structure222defined in part by the stem portion208cand by a valve member224. In one aspect, the valve structure222can be characterized as a secondary internal valve structure224. The valve member224is shown as including a head portion224awith a seal member224band a stem portion224cto which a flange portion224dis either attached or formed with the stem portion224c. In the example shown, the flange portion224dis a nut threaded onto the stem portion224c. The valve structure222is also shown as including a biasing spring226extending between the flange portion224dand a shoulder208eformed in the stem portion208c. The biasing spring226forces the valve member224towards the first end202asuch that the seal member224bforms a seal with the second valve part208. When sufficient fluid pressure exists, the valve member224is moved towards the second end202bsuch that fluid can flow though the secondary fluid passageway218from the first end202ato the second end202bthrough the stem portions206d,208c, even when the second valve part208is in the closed position and blocking flow through the internal passageway202c.

The valve structure222provides useful functions under at least two separate conditions. In a first condition, when the first part200is disconnected from the second part300and the valve structure204is therefore in a closed position, the valve structure222can function as a relief valve. For example, in some applications, an LRU is provided with two first parts200connectable to two second parts300. When the first parts200associated with the LRU are disconnected, fluid will remain in the LRU and in the lines leading up to and including the two first parts200. With such a filled system, thermal expansion of the fluid can occur and must be relieved in order to avoid excessive pressures. With building fluid pressure acting on the valve structures222of the first parts200, the valve structures222will open to relieve pressure in the system. In one example, the valve structures222are configured to open at a cracking pressure of about 120 to 160 psi. Other configurations are possible. For example, a single first part200could provide pressure relief for a hydraulic system or branch.

In a second condition, the valve structure222allows for the valve structure204to move from the closed position to the open position under a hydraulic lock condition. A hydraulic lock condition is a condition in which the fluid in the line connected to the first part200and the fluid within the first part200itself cannot be displaced further into the line or otherwise out of the first part200. As is explained in more detail later, the valve structure204is moved into the open position by the second part300during the connection process to the first part200. In order to move the valve structure204to the open condition, fluid within the first part200must be displaced until, as related previously, the second valve part208is displaced towards first end202asuch that the front face portion208fis moved proximate the stop surface202jto open the internal passageway202cto the second end202b. As this displacement occurs under a hydraulic lock condition, the pressure within the first part builds200until sufficient pressure exists to open the valve structure222. Once the valve structure222opens, the fluid displaced by the movement of the second valve part208is relieved through the valve structure222such that the connection process can continue whereby the valve structure204is moved to the open condition.

Referring toFIGS. 8 and 9, the second part300is shown in greater detail. As shown, the second part300includes a first body302, a second body304connected to the first body302, and a third body306received into and connected to the first body302. In one aspect, the first body302extends between a first end302aand a second end302band defines an internal passageway302cextending between the ends302a,302b. The first body302is further shown as defining a fitting302dproximate the first end302awhereby a threaded or non-threaded pipe, tube, manifold port, or hose can be connected to the first part. The main body302is further shown as being provided with a first collar portion302ewhich can serve as an interface for a tool, such as a wrench, for installing the main body302onto the pipe, tube, manifold port, or hose and/or for holding the second part300stable while the second part300is being installed or removed from the first part200. The first body302is also shown as including a recess302ffor forming a connection with the second body304, recesses302gfor holding rings308that secure the third body306to the first body302while still allowing for the third body306to rotate with respect to the first body302. The first body302also defines a shoulder302hfor supporting a spring310acting against a sleeve312surrounding the second body304. The first body302is further shown as including a recess302ifor retaining a seal314and backup ring316such that a seal is formed between the second body304and the sleeve312.

The second body304is shown as extending between a first end304aand a second end304band defining an internal passageway304cextending therebetween. The second body304is shown as having a flange portion304dwhich is received into the first part recess302fto connect the first and second bodies302,304together. The second body304is further shown as including one or more apertures304efor allowing fluid to pass between the internal passageway304cand the exterior of the second body304. When the sleeve312is in a closed or extended position, as biased by the spring310and as shown atFIG. 9, the sleeve312covers the apertures304esuch that fluid is blocked from flowing through the apertures304esuch that fluid is prevented from flowing between the internal passageways302c,304cand an internal passageway306cdefined by the third body306. Accordingly, the sleeve312and apertures304ecan be characterized as forming a valve structure324. In one aspect, the valve structure324can be characterized as a primary internal valve structure324. The second body304is also shown as being provided with an open end304fat the second end304b. A valve structure318, discussed in more detail later, is mounted to the second body304such that the open end304fis in fluid communication with the valve structure318.

The third body306is shown as extending between a first end306aand a second end306band defines an internal structure306cextending therebetween. In one aspect, the third body306includes a threaded portion306dproximate the second end306bfor receiving the threaded portion202fof the first part200such that the first and second parts200,300can be connected together. The third body306is further shown as including a shoulder306eagainst which a spring320acts. A sleeve322surrounds the third body306and includes a shoulder306eagainst which an opposite end of the spring320acts to bias the sleeve towards the second end306bsuch that the tab portions322bare held into the notches202hof the first part200such that the threaded connection between the threaded portions306d,202fcannot be disengaged without first retracting the sleeve322against the force of the spring320, as previously described above.

In one aspect, the valve structure318is defined in part by the second body304and a valve member328. The valve structure318can be characterized as a secondary internal valve structure318. Defining the first end304a, the second body304defines a valve housing portion304gdefining an internal passageway304hwithin which the valve member328is disposed. The valve member328is shown as including a head portion328awith a seal member328band a stem portion328c. The valve structure318is also shown as including a biasing spring330extending between the head portion328aand a flange or ring structure332, shown as being retained in place in the internal passageway304hby a clip334. Accordingly, the biasing spring330biases the head portion328atowards the first end304asuch that a seal is formed between the seal member328band the second body304. Accordingly, the valve structure318functions as a check valve to prevent fluid from passing through the internal passageway304h, and thus also through the interconnected passageway304c, when the second part300is disconnected from the first part200.

In the closed position of the valve structure318, as shown atFIG. 9, a nose portion328dof the valve member328extends beyond the head portion328aand seal member328b, and can act as a point of contact with the head portion224aof the valve part224. In one example, a small axial gap exists between the head portion224aand the head portion224aof the valve part224when the internal valve structures are in the closed positions. Accordingly, when the valve part224is moved into the open position to relieve fluid pressure in the first part200, as previously described, the head portion224acan physically move the valve member328into the open position such that the relieved fluid from the first part200can be passed into the second part300internal passageway304c/302c. A seal member336is also shown as being provided at the first end304aof the second body304such that a seal can be formed between the second body304and the second valve part208of the first part200when the first and second parts200,300are connected together.

Referring toFIGS. 12 and 13, it can be seen that the first part200is connected to the second part300, and that the valve structures222and318are in the closed position. When the first and second parts200,300are fully connected together, the sleeve312is moved from the closed position into the open position via contact between a surface312aof the sleeve312and the second end202bof the first part main body202. Additionally, the valve structure204is also placed in the fully open position as the valve structure318of the second part300contacts and pushes the valve part208of the first part200against the force of the spring212. As a result, upon connecting the first and second parts200,300, the internal fluid passageways302c,304c, and202care placed in fluid communication with each other to define a primary fluid passageway through the first and second parts200,300. Additionally, as most easily seen atFIGS. 11 and 13, when the first and second parts200,300are connected together, the internal passageways304h/304cand218are also placed in fluid communication with each other to define a secondary fluid passageway that is opened and closed by operation of the valve structures318,204. The passageways304cand218also form an internal cavity338into which the nose portion328dand head portion224acan extend. In one configuration, the nose portion328ddoes not physically contact the head portion224ato open the valve structure318, and instead pressure from fluid entering the cavity338via the valve structure204causes the valve structure318to open.

In addition to the above-described configuration, additional configurations are possible. In some examples, the second part300can be additionally provided with the valve structure222such that a relief valve function could be obtained in the second part300as well. In some examples, the first part200can be additionally provided with the valve structure318such that a bleed valve function could be obtained in the first part200as well. In some examples, the first and second part200,300have similarly configured valve structures, each with a relief and bleed valve such that relief and bleed functions are realized in each of the first and second parts200,300. An example of such an arrangement is illustrated atFIGS. 14 and 15.

As shown atFIGS. 14 and 15, the first and second parts200,300are respectively provided with a valve structure204,304and a valve structure250,350. Each of the valve structures250,350combines the features of the valve structures222and318such that bleed and relief functions are provided by each of the valve structures250,350. The valve structures250,350are generally configured in a similar fashion, but slight differences exist due to the physical differences between the housing bodies of the first and second parts200,300as is discussed later. As shown, the valve structures250,350of the first and second parts200,300oppose each other along a common axis and extend into the cavity338. Accordingly, each of the valve structures250,350can bleed into the cavity338when the first parts200,300are connected to each other. Similarly, when the first and second parts200,300are disconnected, the valve structures250,350can provide a relieve valve function to bleed fluid when thermal expansion of fluid causes a buildup of sufficient pressure.

As shown, the valve structure250includes a pair of concentrically arranged valve structures260,270. Accordingly, the valve structure260can be characterized as being an outer valve structure260and the valve structure270can be characterized as being an inner valve structure270.

In one aspect, the outer valve structure260is formed by the stem portion206dof the first valve part206and a sleeve part262defining an end face262a, an outer flange or shoulder portion262band an inner shoulder portion262c. A seal264circumscribes the sleeve part262and is supported by the outer flange or shoulder portion262b. A spring266is also provided and extends between the outer flange or shoulder portion262band an end of the stem portion206d. The spring266biases the sleeve part262towards the second end202bof the valve part200such that a seal forms between the seal part264and an inner surface208gof the second valve part208. In this position, the outer valve structure260is in a closed position such that flow is prevented through the secondary fluid passageway218, which in this configuration, is a flow passageway that extends between the stem portion206dand an apertured outer sleeve portion208hof the second valve part208.

In one aspect, the inner valve structure270is configured similar to previously described valve structure222, however, the inner valve structure270is partially defined by the sleeve part262of the outer valve structure270instead of the stem portion208c. As shown, the inner valve structure270is shown as additionally including a valve member272. The valve member272is shown as including a head portion272awith a seal member272band a stem portion272cto which a flange portion272dis either attached or formed with the stem portion272c. In the example shown, the flange portion272dis a nut threaded onto the stem portion272c. The valve structure250is also shown as including a biasing spring274extending between the flange portion272dand the inner shoulder262cformed in the sleeve262. The biasing spring274forces the valve member272towards the first end202asuch that the seal member272bforms a seal with the end face262aof the sleeve262. When sufficient fluid pressure exists, the valve member272is moved towards the second end202bsuch that fluid can flow though the sleeve262from the first end202ato the second end202b. The interior passageway of the sleeve262can be characterized as being a portion of the secondary fluid passageway218. The secondary fluid passageway218is also defined by apertures262din the sleeve262and the interstitial space between the sleeve262and the outer sleeve portion208hleading to the second end262a.

The valve structure350is generally similar to the valve structure250and includes a pair of concentrically arranged valve structures360,370. Accordingly, the valve structure360can be characterized as being an outer valve structure360similar to outer valve structure260and the valve structure370can be characterized as being an inner valve structure370similar to inner valve structure270. Accordingly, the valve structure360includes a sleeve part362defining an end face362a, an outer flange or shoulder portion362band an inner shoulder portion362c, a seal364, and a spring366. Likewise, the valve structure370includes a valve member372having a head portion372a, a seal member372b, a stem portion372c, a flange portion372d, and a biasing spring374. As many components are similar between the valve structures250and350, the descriptions need not be repeated again here for the valve structures350.

A primary difference between valve structures250and350is that the valve structure350is provided in and supported by the stationary body304rather than being disposed within a moving valve structure, as is valve structure250. As a result, the biasing spring366for the valve structure350is supported by the flange or ring structure332, shown as being retained in place in the internal passageway304hby a clip334. This is the same general configuration as previously described for the valve structure318.

With the configuration shown atFIGS. 14 and 15, the head portions272b,372bof the valve parts272,372are arranged such that they contact each other when the valve parts200,300are connected together. By virtue of this contact, the outer valve structures260,360are opened such that the secondary fluid passageways of the first and second coupling parts200,300are placed in fluid communication with each other. When coupling the parts200,300together, if one of the coupling parts200,300is under a hydraulic lock condition, the associated inner valve structure270,370can open to relieve fluid pressure into the other coupling secondary passageway. This action will also cause the opposing outer valve structure260or360to open further. Accordingly, during the coupling process, the outer valve structure260acts as a bleed valve for the inner valve structure370when the inner valve structure operates as a relief valve while the outer valve structure360acts as a bleed valve for the inner valve structure270when the inner valve structure operates as a relief valve. When the coupling parts200,300are disconnected from each other, the inner valve structures270,370can act as relief valves while the outer valve structures260,360act as opposing poppet or check valves. It is also noted that relief valves270,370will only communicate fluid when the coupling parts200,300are in disconnected position. During connection of the coupling parts200,300, the primary valves (e.g. valve structures204,324) do not begin to open until after the relief valve heads272a,372acontact whereby the outer valve structures260,360are forced open allowing flow through the secondary flow passage. After the coupling parts200,300are fully connected, the relief valves270,370should remain closed and the outer valves260,360should remain open, as shown inFIGS. 14 and 15.

The depicted coupling parts200,300are shown as exemplary combinations of the disclosed internal valve structures. However, other combinations are possible. For example, a quick disconnect coupling100could be provided with a first coupling part having a valve structure similar to the valve structure222depicted inFIGS. 7 and 10-13, and provided with a second coupling part having a valve structure similar to the valve structure350with valve structures360and370. In such an example, the valve structure360is biased toward the closed, sealed position when the coupling parts are connected together. With such a configuration, a relief valve function is provided in one coupling part, and a combination relief and poppet or check valve function is provided by the other coupling part. In another example, the valve structures250,350are configured such that the head portions272a,372ado not initially contact when the coupling parts are connected together, thereby creating a small axial gap between the head portions272a,372ain the same manner a small axial gap is created between the head portion224aand the nose portion328din the example shown atFIGS. 12 and 13. In such an example, the valve structures260,360are biased towards the closed, sealed position when the coupling parts are connected together. Although the coupling parts200are shown as male coupling parts and the coupling parts300are shown as female coupling parts, the reverse arrangement is also possible.

From the forgoing detailed description, it will be evident that modifications and variations can be made in the aspects of the disclosure without departing from the spirit or scope of the aspects. While the best modes for carrying out the many aspects of the present teachings have been described in detail, those familiar with the art to which these teachings relate will recognize various alternative aspects for practicing the present teachings that are within the scope of the appended claims.