Patent Description:
Disadvantages of the traditional connectors reside in their relatively high weight and production costs since they are predominantly made of metal. Further, they have a quite long axial extension and provide two potential leakage positions. There is a first leakage position at the threaded portion where a first O-ring forms a seal between the connector and the female part and a second leakage position within the inner periphery of the sleeve portion where a second O-ring forms a seal between the connector and the male part.

<CIT> describes a quick connector in which the threaded part is eliminated, and the connector is not screwed but clinched or staked or swaged in a non-removable fashion to the female part. While this conventional solution eliminates the need of the first O-ring to form a seal between the connector and the female part, it suffers from the disadvantage that the quick connector is permanently connected to the female part. Also, the quick connector still protrudes from the outer surface of the female part when being permanently connected thereto which is undesirable for space saving connector solutions, particularly in fields like battery cooling required in automotive systems for e-mobility.

<CIT> and <CIT> disclose conventional quick connectors made of plastics. The connectors have first tongue portions protruding radially inwards for snapping engagement with the male part and second tongue portions protruding radially outwards for snapping engagement with the female part. However, the constructional setup of these conventional connectors is relatively complex and prone to damages since the first and second tongue portions are surrounded by a radial cut out of the material at the connector side wall to which they are connected by a small axial web only. Further, the first and second tongue portions are provided at axially spaced portions of the connector so that the connector has a quite long axial extension and protrudes from the outer surface of the female part.

<CIT> discloses a quick connect fluid fitting assembly with the features in the preamble of present claim <NUM>. Other conventional connectors are described in <CIT>, <CIT>, and <CIT>.

The object of the present invention is to reduce the weight and cost of the connector, to simplify its constructional setup, to shorten its axial extension and to reduce the number of potential leakage positions.

The object is met by the connector defined in present claim <NUM>. The dependent claims relate to preferred embodiments and additionally call for a connection system comprising the connector and the male and female parts to be connected with each other.

In accordance with the present invention, the quick connector comprises a tubular retaining means which is to be set within the mouth portion of the female part and which comprises first and second flexing members for snapping engagement with both the female part and the male part. Unlike many conventional solutions of quick connectors made of plastics, the present retaining means has the first and second flexing members provided at circumferentially spaced portions. This simplifies the constructional setup of the quick connector and allows to minimise the axial dimension thereof.

According to a preferred embodiment of the present invention, there are plural first flexing members for snapping engagement with the male part and plural second flexing members for snapping engagement with the female part. Axial slits are formed between the alternately arranged first and second flexing members to increase their elastic deformability. Preferably, the retaining means is made of a polymer-based plastics material. It is particularly preferable to form the retaining means as an integral structural body by injecting moulding or the like from mouldable plastics material. Thereby, the production costs and the durability of the connector achieve most competitive values.

The tubular retaining means has a ring-shaped base portion from which the first and second flexing members protrude in an axial direction with the axial slits in-between. The first flexing member has a first ring segment from which the first tongue portion protrudes radially inwards. Likewise, the second flexing member has a second ring segment from which the second tongue portion protrudes radially outwards. The first and second tongue portion may also have the general shape of a ring segment, and the overall shape of the retaining means may have n-fold symmetry, n being an integer, wherein n=<NUM> in the most preferred embodiment.

The sealing means, preferably an O-ring, an X-seal or a lip seal, is positioned axially frontwards of the retaining means within the mouth portion of the female part. The sealing position does not axially overlap with the retaining means so that the sealing means is able to contact both the male part and the female part when the quick connector is in its locked condition. Thereby, one single sealing position is sufficient for the coupling between the male and female parts so that there is only one single potential leakage position.

The present invention preferably further comprises a plug for holding the retaining means and the sealing means in their condition before final locking attachment of the male part. The retaining means and the sealing means are received at a shaft portion of the plug which has a smaller outer diameter than a gripping portion thereof. The plug serves as a place holder for the male part and is useful in quick and safe handling of the connector during the manufacturing and delivering of the connector, as well as during its later assembling in the fluid connection system, in particular in automobile industry.

The shaft portion preferably has a tapered section for gradually stretching the first flexing member and/or a groove section for receiving the first tongue portion. The second flexing member is adapted to engage with the female part to keep the connector in its locked and sealed state until the plug is to be replaced by the male part. The groove section has a smaller diameter than the circumferentially adjacent portions of the plug and therefore allows the first flexing member to contract due to its elasticity in the radial direction so that it engages with the plug. This state is useful for safe transport or for pressure tests before installation.

In order to release the plug, the plug is turned about its longitudinal axis so that the first flexing member no longer engages with the groove section of the plug. In this state, the plug can be taken out from the connector kept engaged with the female part so that the plug can be replaced by the male part. In summary, the plug allows to close the mouth portion of the female part in a fully sealed condition at a first rotational position and the plug may be released at a second rotational position when the plug is to be replaced by the male part.

When the plug is replaced by the male part of the fluid connection system, preferably a spigot, the first flexing member is again stretched by the male part in a similar way in the radial direction as by the plug to bring the connector in its fully locked state. The female part has a groove formed on the inner periphery of its mouth portion. The groove may have an annular or any other suitable shape. It has a larger inner diameter than the axially adjacent portions of the mouth portion so that the second tongue portion of the second flexing member can lock into the groove when being stretched against its elastic reset force due to the insertion of the male part.

Details of the invention and its embodiments will be explained with reference to the accompanying drawings. Therein shows:.

<FIG> shows the retaining means <NUM> in a perspective side view. The shown retaining means <NUM> is made of plastics material, more specifically of a polymer-based plastics material, and is even more specifically obtained as an integral body by injection moulding or the like. The retaining means <NUM> has a ring-shaped base portion <NUM> which has a cylindrical outer surface and a tapered, funnel-like inner surface which can best be seen in <FIG> below. From the ring-shaped base portion <NUM>, the first and second flexing members <NUM>, <NUM> protrude in an axial direction. The first and second flexing members <NUM>, <NUM> are arranged alternately with axial slits <NUM> provided between each pair of first and second flexing members <NUM>, <NUM>. Due to the slits <NUM> and the general characteristics of the plastic material, the first and second flexing members <NUM>, <NUM> have some elastic deformability in the radial direction, i.e. they can be flexibly deformed to a certain extent in a radial direction orthogonal to the axial extension of the tubular retaining means <NUM>.

As shown in greater detail in <FIG>, each of the two first flexing members <NUM> has a first ring segment <NUM> and a first tongue portion protruding from the first ring segment <NUM> inwardly in a radial direction. The first tongue portion <NUM> itself has again the shape of a ring segment. Likewise, the two second flexing members <NUM> each have a second ring segment <NUM> and a second tongue portion <NUM> protruding radially outwards from the second ring segment <NUM>. In the shown embodiment with two first and two second flexing members <NUM>, <NUM>, the tubular retaining means <NUM> has a two-fold rotational symmetry and each of the ring segments substantially has about a quarter ring shape. However, solutions with more than two or even just one of the first and one of the second flexing members are possible and lead to different kinds of a generally n-fold rotational symmetry.

In the perspective exploded view of present <FIG>, the retaining means <NUM> is shown in its pre-assembled state next to a sealing means <NUM> and in front of the female part <NUM> formed as a block. For illustration purposes, the retaining means <NUM> and the sealing means <NUM> are shown in a pre-assembled position in present <FIG>. Their assembled position is shown in present <FIG>. Each of the cross-sectional views in <FIG> is taken along two of the axial slits <NUM>.

In the perspective view of the fluid connection system shown in <FIG>, the female part <NUM> is formed as a hole in a block. While conventional fluid connection systems provided an inner threading in the hole for screwing a threaded portion of the connector, the mouth portion <NUM> of the female part <NUM> is adapted to fully receive and engage with the connector without such threaded portion. The inserting direction of the spigot <NUM> in <FIG> extends downwards in the Figure and is hereafter designated as the frontward direction. The opposite direction is designated as the backward direction.

The female part <NUM> has a mouth portion <NUM> which has a diameter just large enough to receive the sealing means and the ring-shaped base portion <NUM> one after another. However, the diameter of the mouth portion <NUM> is smaller than the outer diameter of the second tongue portion <NUM> of the second flexing member <NUM>. By pushing the retaining means <NUM> in the downward direction into the mouth portion <NUM>, the second flexing members <NUM> will elastically deform radially inwards so that their outer diameter becomes small enough to enter the mouth portion <NUM>. As soon as the second tongue portions <NUM> will reach the axial position of an annular groove <NUM> formed axially distant from the outer surface of the mouth portion <NUM>, the second tongue portions <NUM> will relax into their original state and snappingly engage with the groove <NUM> of the female part <NUM>.

Thereby, the connection state shown in present <FIG> is obtained, in which the sealing means <NUM> and the retaining means <NUM> reach a locked state and the retaining means <NUM> is engaged with the female part <NUM> by the snapping interaction between the second tongue portions <NUM> and the annular groove <NUM>. As can be seen from present <FIG>, the retaining means <NUM> does not protrude axially from the female part <NUM> but is fully received within its mouth portion <NUM>. This is of particular advantage for processing and delivering the female part <NUM> with the retaining means <NUM> in this pre-locked state. Further, the retaining means <NUM> stops the sealing means <NUM> from falling out of the mouth part <NUM> due to its locked axial positioning. The sealing means <NUM> rests at a step portion <NUM> of the female part <NUM>. The step <NUM> has a larger diameter than the axially adjacent portion <NUM> in the downward direction of the female part <NUM> so that the sealing means <NUM> cannot move further inward into the female part <NUM> either.

An O-ring <NUM> as the sealing means is to be positioned at an annular step <NUM> (see <FIG>) formed at the frontward end of the mouth portion <NUM>. The O-ring <NUM> and the other parts of the connector are shown in <FIG> axially distant from the mouth portion <NUM>, and the spigot <NUM> as the male part is shown in <FIG> axially spaced even more backward therefrom. In order to establish the fully connected state of the fluid connection system shown in <FIG> and <FIG>, the sealing means <NUM> is first positioned within the mouth portion <NUM> at the step <NUM> of the female part <NUM> as shown in <FIG>, the ring-shaped retaining means <NUM> and then positioned axially backwards and adjacent to the sealing means <NUM>. The connector already comes into a pre-locked engagement state when being inserted into the mouth portion <NUM>. This is because the second flexing member <NUM> of the retaining means <NUM> will undergo some compression when entering the mouth portion <NUM> and the second tongue portion <NUM> thereof will then snap into the annular groove <NUM> of the female part <NUM>. Thereby, the second flexing member <NUM> prevents the retaining means <NUM> and the sealing means <NUM> from falling out of the mouth portion <NUM> during transport or the like.

Finally, as shown in <FIG>, the male part <NUM> is pushed through the retaining means <NUM> and the sealing means <NUM> until the first tongue portion <NUM> of the first flexing member <NUM> which protrudes radially inwards forms a snapping engagement with the male part <NUM>. The tubular male part <NUM> has a standard outer diameter at its most frontward portion which then gradually increases in a tapered portion <NUM> arranged for gradually stretching the second flexing member <NUM> when the male part <NUM> is pushed through the retaining means <NUM>. Backwards from the tapered portion <NUM>, there is a thickened portion <NUM> which has an outer diameter large enough to keep the second flexing members <NUM>, more specifically, the two second tongue portions <NUM> thereof, in its locked state within the annular groove <NUM>. More specifically, the two first flexing members <NUM> are first stretched by the tapered portion <NUM> and the two first tongue portions <NUM> then come to rest on the thickened portion <NUM> backwards of the tapered portion <NUM>. The ratchet formed at the backward end of the tapered portion <NUM> abuts against the first tongue portion <NUM> of the first flexing member <NUM> so that the male part <NUM> remains locked within in the connector and cannot be moved backwards anymore.

<FIG> shows the fluid connection system in its locked state. As described previously, the female part <NUM> is formed as a hole in a block. The hole has a standard diameter portion <NUM> which is slightly larger than the outer diameter of the frontward portion of the male part <NUM>. Backwards from the standard diameter portion <NUM>, there is the mouth portion <NUM> having a larger inner diameter than the standard diameter portion <NUM>. The mouth portion <NUM> has the step <NUM> for receiving the sealing means <NUM> and a portion with a larger diameter than that of the step <NUM> in which the retaining means <NUM> is to be received such that it is not protruding axially outwards from the female part <NUM>. The mouth portion <NUM> further has an annular groove <NUM> with a larger diameter than the adjacent backward part of the mouth portion <NUM> so that the two second flexing members <NUM> can protrude into the annular groove <NUM> when being brought by the tubular male part <NUM> into their locked state.

As can be seen by a comparison of the sealing means in the cross-sectional views of <FIG>, the sealing means <NUM> is expanded when the male part <NUM> is pushed through the retaining means <NUM> and the sealing means <NUM> into the fully locked position shown in present <FIG>. Thereby, the fluid connection system reaches a state in which the male part <NUM> is fully sealed against the female part <NUM>. This is due to the fact that the most frontward portion of the male part <NUM> has an outer diameter which is slightly larger than the inner diameter of the sealing means <NUM> so that the sealing means <NUM> has to radially expand when the male part <NUM> is pushed through with its most frontward portion.

Before insertion of the male part <NUM>, the connector is often held in a pre-locked state by a plug <NUM>. As can be seen best in the cross-sectional view of <FIG>, the shaft portion <NUM> of the plug <NUM> has a standard outer diameter coinciding with that of the male part <NUM> for which it serves as a place holder. Also, the tapered section <NUM> substantially corresponds to the tapered portion <NUM> of the male part <NUM> and serves for stretching the second flexing member <NUM> when the plug <NUM> is pushed through the retaining means <NUM> and the sealing means <NUM>.

The plug <NUM> further has stopping ridges <NUM> extending in the axial direction and providing the plug <NUM> with an enlarged outer diameter for stopping abutment against the retaining means <NUM> when the plug <NUM> is in its fully inserted position. A gripping portion <NUM> of the plug <NUM> comprises the three stopping ridges <NUM> and a disk portion <NUM>. The stopping ridges <NUM> allow easy rotation of the plug <NUM> by a user's hand and sufficiently enlarge the diameter of the plug to prevent it from being pushed too far into the connector. They further may indicate to the user at which circumferential portions of the plug <NUM> the two groove sections <NUM> are formed and they extend up to a disk portion <NUM> forming the terminal edge of the plug <NUM> at the most backward portion.

<FIG> show the plug <NUM> in a first rotational position in which the groove sections <NUM> snappingly engage with the first tongue portions <NUM> of the retaining means <NUM>. In this first rotational position, the plug <NUM> is in an axially locked position and closes the mouth portion <NUM> so that no dirt can enter. Due to the expansion of the sealing means <NUM>, achieved by pushing the plug <NUM> through the retaining means <NUM> and the sealing means <NUM> into the fully locked position shown in present <FIG>, the plug also realizes a fully sealed state in which no liquid or other fluids can enter or exit the mouth portion <NUM>. This is due to the fact that the most frontward portion of the plug <NUM> has an outer diameter which is slightly larger than the inner diameter of the sealing means <NUM> so that the sealing means <NUM> has to radially expand when the plug <NUM> is pushed through with its most frontward portion. The sealing capability of the connector in a pre-assembled state achieved by the plug <NUM> is of most advantage during various processing and testing steps, particularly in car industry relating to the fluid cooling of electric driving systems.

The plug can be rotated about its longitudinal axis from the shown first rotational state into a second rotational state. In the shown embodiment, this rotation is achieved by turning the plug <NUM> by <NUM> degrees in the clockwise or counter-clockwise direction. In this second rotational state, the groove sections <NUM> will circumferentially move out of the snapping engagement with the first tongue portions <NUM> so that the plug <NUM> gets from its locked state into its released state. Even though the plug <NUM> is still in sealing engagement with the sealing means <NUM> with its most frontward portion, it is no longer locked in its axial direction so that it can be pulled backwards out of the mouth portion <NUM> of the female part. This is normally the time when the plug <NUM> is to be replaced by the male part <NUM> shown in <FIG> and explained in reference to those Figures further above.

In summary, the present invention provides a quick connector made of plastics material for establishing a snapping connection between a tubular male part <NUM> and female part <NUM> of a fluid connection system. The connector has retaining means <NUM> adapted to be set within the mouth portion <NUM> of the female part <NUM> and having first and second flexing members <NUM>, <NUM> for snapping engagement with the male part <NUM> and the female part <NUM>, respectively. The first and second flexing members <NUM>, <NUM> are provided at circumferentially spaced portions of the retaining means <NUM> so that the overall axial dimensioning of the retaining means <NUM> is reduced.

Claim 1:
A quick connector for connecting a tubular male part (<NUM>) to a female part (<NUM>), comprising:
sealing means (<NUM>) adapted to be set within a mouth portion (<NUM>) of the female part (<NUM>) to form a seal between the male part (<NUM>) and the female part (<NUM>); and
tubular retaining means (<NUM>) adapted to be set within the mouth portion (<NUM>) and having at least one first flexing member (<NUM>) with a first tongue portion (<NUM>) protruding radially inwards for snapping engagement with the male part (<NUM>) and at least one second flexing member (<NUM>) with a second tongue portion (<NUM>) protruding radially outwards for snapping engagement with the female part (<NUM>),
wherein the first and second flexing members (<NUM>, <NUM>) are provided at circumferentially spaced portions of the retaining means (<NUM>),
wherein the tubular retaining means (<NUM>) has a ring-shaped base portion (<NUM>) from which the first and second flexing members (<NUM>, <NUM>) protrude in an axial direction with axial slits (<NUM>) formed in-between, so that the first and second flexing members (<NUM>, <NUM>) can be flexibly deformed in a radial direction orthogonal to the axial extension of the tubular retaining means (<NUM>), and
wherein the first flexing member (<NUM>) has a first ring segment (<NUM>) axially protruding from the ring-shaped base portion (<NUM>),
characterised in that the first tongue portion (<NUM>) protrudes orthogonally and radially inwardly from the first ring segment (<NUM>).