GB2312482A

GB2312482A - Coupling device for corrugated tubes

Info

Publication number: GB2312482A
Application number: GB9707779A
Authority: GB
Inventors: Jurgen Rumpel
Original assignee: REIKU GmbH
Current assignee: REIKU GmbH
Priority date: 1996-04-24
Filing date: 1997-04-17
Publication date: 1997-10-29
Anticipated expiration: 2017-04-17
Also published as: ITFI970087A0; DE29607470U1; ITFI970087A1; DE19714661C2; GB9707779D0; DE19714661A1; IT1291836B1; GB2312482B

Abstract

The device has a body 5 for receiving the tube end 3 and a ring 7 slideably mounted on the body and having resiliently flexible tongues 17 with engagement ribs 19 at the inner periphery thereof for engagement into a peripheral groove of the corrugated tube (3). The tongues 17 extend through openings 15 of the body 5 and Cam surfaces 21 formed at the inner periphery of the tongues (17, 57) can be brought into engagement with shoulders 23 of the body 5 by displacement of the ring for pivoting the tongues 17 radially outwardly into a release position. Cooperating surfaces of the tongues 17 and the forward edges 27 of the openings 15 aid retention of the tongues in the tube groove. The device can connect the tube to a wall and can be a T-piece or angle piece.

Description

Coupling device for corrugated tubes The invention relates to a coupling device for corrugated tubes having the features as defined in the preamble portion of claim 1.

Coupling devices of this kind have been known from DE 40 20 171 C1 and EP 0 331 116 B1. In these prior art coupling devices the ring carrying the tongues with engagement ribs is slidably mounted at the inner periphery of the body, and the ring has a flange engaging with the end face of the body for defining a release position of said ring which enables the tongues to pivot radially outwardly, whereby the engagement ribs are free to yield to the corrugated tube if this is pushed into the coupling device.

The engagement ribs may then snap into a peripheral groove of the corrugated tube in order to block the tube to the coupling device. When the tube in this blocked condition is subjected to a pulling force the ring is carried into a position in which the body blocks the tongues against radially outward movement, whereby the tongues can not release the corrugated tube. In order to release the corrugated tube the ring has to be manually retained in the release position and then a pulling force must be exerted on the corrugated tube. In such case the engagement ribs can snap out of the groove of a tube, provided the ribs of the corrugations are sufficiently inclined with respect to a radial plane. However, if the engagement ribs and/. or the corrugations of the tube are strongly inclined a pulling force on the tube may result in unwanted release of the tube. If the inclination is too small the pulling force required for a desired release of the corrugated tube is too high whereby the tube may be damaged.

It is an object of the invention to provide a coupling device of the above mentioned type which enables a more simple and easy removal of the corrugated tube from the device.

According to the invention there is provided a coupling device as defined in claim 1. The dependent claims relate to further preferred featurcs of the invention.

In the coupling device according to the invention the ring is mounted at the outer periphery of the body. Therefore, the ring can be easily gripped by hand and displaced in such an axial direction that the inclined deflection faces of the tongues engage with corresponding shoulders of the body, whereby the tongues are positively pivoted radially outwardly in order to release the corrugated tube. The corrugated tube can then be drawn out of the coupling device without exerting a substantial force.

Embodimeiits of L invention are now described with reference to the drawings.

Fig. 1 shows a coupling device according to the invention in side view, and partially in longitudinal section, Fig. 2 shows the coupling device of Fig. 1 in side in a plane rotated by 900 with respect to that of Fig. 1, Fig. 3 shows the coupling device in the same view as in Fig. 1 in the released position, Fig. 4 shows the coupling device in the same view as Fig. 1 in the locking position.

Fig. 5 shows the body of a coupling device ac cording to a second embodiment of the invention, in side view and partially in longitudinal section.

Fig. 6 shows the body of Fig. 5 in side view and partial longitudinal section in a plane ro tated by 900 with respect to Figure 5.

Figs. 7 and 8 show the ring for the coupling device ac cording to the second embodiment, in side view in two planes rotated by 900 to each other, and partially in section.

Fig. 9 shows a side view, partially in section, of the coupling device according to the second embodiment having a corrugated tube inser ted.

As shown in Fig. 1 and Fig. 2 the coupling element 1 for receiving a pheripherally corrugated tube 3 comprises a body 5 and a ring 7 which is displaceably mounted at the outer periphery of the body 5. The corrugated tube 3 which shall be coupled to the coupling device can be pushed into the body 5 until its end face engages with an inner shoulder 9 of the body 5. An annular seal (not shown) can be located at the inner shoulder 9, if desired. The end of the body 5 opposite to the opening receiving the corrugated tube 3 can be formed as a fastening element or fitting in any desired manner. In the embodiment shown the body 5 comprises a connecting section having a male screw thread 11 which may be fitted into an opening of a wall and fixed with a nut (not shown). A part of the outer surface of the body 5 can be formed as a hexagon 13 for engagement of a wrench. The connecting portion of the coupling device can be formed in any other way, for example the coupling device 1 may be formed as a male or female coupling portion, a Tpiece or an angle piece for connecting two cr more corrugated tubes 3.

The wall of the body 5 has two diametrically opposed window-like openings 15. The ring 7 slidably mounted to the outer periphery of the body 5 has two axially projecting flexible tongues 17. Each tongue 15 extends into one of the window-like openings 15 and has its free end formed with a radially inward projecting engagement rib 19 for engagement into one of the peripheral grooves of the corrugated tube 3. Near the foot portion of each tongue 17 where the tongue is integrally connected with the ring 7 an inclined cam surface 21 is formed at the radially inner side thereof for co-operation with a similarly inclined shoulder 23 of the corresponding opening 15 of the body 5. Moreover, the free end of each tongue 17 is formed with an axially directed protection 25 which may engage under an inwardly directed inclined surface 27 at the upper end of the opening 15 of the body 5.

In Fig. 1 the ring 7 is in its middle position which is the unbiased normal position. Due to the resilient restoring force of each tongue 17 the engagement rib thereof engages into a groove of the corrugated tube 3. Each tongue 17 may perform a yielding movement by resilient by flexing radially outwardly in the opening 15 of the body 5.

In Fig. 3 and Fig. 4 the corrugated tube 3 has been omitted for simplification of the drawing. In Fig. 3 the ring 7 has been displaced in a direction corresponding to the insertion of the corrugated tube 3 (downward as shown in the drawing) into a released position. During this displacement the interior inclined cam surface 21 of each tongue 17 slides up on the corresponding inclined shoulder 23 of the body whereby the tongue 17 flexes radially outwardly so that the engagement rib 19 does no longer project into the interior channel of the body 5 and the corrugations of the corrugated tube 3 may be moved past the engagement ribs 15.

Thus, in the position shown in Fig. 3 a corrugated tube can be inserted into the coupling device 1 or pulled out-of the coupling device 1 without using substantial force. This particularly provides a very easy de-coupling of the tube because the engagement ribs 19 of the tongues 17 completely release the tube. For performing the de-coupling operation the ring 7 must be manually pushed into the release the position shown in Fig. 3 using a manual force which overcomes the resilient bending resistance of the tongues 17. For insertion and coupling of the corrugated tube it is sufficient to push the corrugated tube with sufficient force into the coupling device, whereby the insertion force of the corrugated tube 3 pushes the ring 7 into the release position shown in Fig. 3.

If the coupled corrugated tube shown in Fig. 1 is subjected to a pulling force the tribe 3 will carry the ring 7 into the locking position shown in Fig. 4. In this position the projection 25 at the ends of each tongue 17 engages below the corresponding inwardly inclined locking face 27 of the body 5 whereby the tongues 17 and the engagement ribs 19 thereof are locked against radially outward movement. This is the locking position which prevents a de-coupling of the corrugated tube 3. Increasing the pulling force on the corrugated tube 3 increases the locking effect.

Preferably, the body S and the ring 7 with the tongues 17, respectively, are each integrally moulded of resin. The body 5 and the ring 7 may be so dimensioned that the ring 7 may be pushed onto the body 5 with elastic expansion and thereafter remains secured to the body 5.

The body 5 of the second embodiment as shown in Fig. 5 and 6 is substantially identical to the body 5 as shown in Fig.

1 to 4 and will therefore not be described again in detail.

Only the following details are different from the body 5 of the first embodiment: As shown in Fig. 5 and 6, the shoulder 231 at the lower edge nf the window-like opening 15 does not have a conical inclination but a convex-rounded shape, for improving the cooperation with the corresponding cam surface of the ring.

The second difference relates to the wall of the body 5 which has thickened portions 29 in the regions between the window-like openings 15, each thickened portion 29 having a lower end forming an undercut 31 for locating an annular seal 33 inserted into the body 5 (shown only in Fig. 6).

This annular seal 33 over the larger part of his length has the form of a sleeve seal for sealingly engaging the outer periphery of the corrugated tube. At its lower end the annular seal 33 is formed with an interior projecting angled flange 35 which forms a groove 30 for receiving the end portion of the corrugated tube.

Fig. 7 and 8 show a ring 47 for use with the body 5 shown in Fig. 5 and 6. This ring 47 has a substantially larger axial length than the ring 7 of the embodiment shown in Figure 1 to 4. In the wall of the ring 47 there are formed two diametrically opposed window-like openings 49. In each opening 49 there is positioned a tongue 57 integrally connected to the wall of the ring 47 via a laterally restricted bridge 51. The lateral restriction of the bridge 51 improves the flexibility of the tongue 57. At the inner peripheral side the tongue 57 is formed with an engagement rib 59 for engagement into a groove of the corrugated tube.

The free end of each tongue is formed with an axial projection 65 for a cooperation with the corresponding locking surface of the body for blocking the tongue 47, as has been described above for the projection 25 of the embodiment shown in Fig. 1 to 4.

Near its foot portion each tongue 47 at its inner peripheral side is formed with a cam surface 61 which has a convex rounded shape rather than a conically tapering shape as the cam surface 21 of the embodiment of Fig. 1 to 4. The cam surface 41 with convex rounded shape cooperates with the convex rounded shoulder 23' of the body 5 for excerting a radially outward directed force onto the tongue 27, when the ring 47 is pushed downward as seen in Fig. 5 to 8, whereby the tongue is pivoted radially outwardly into the release position.

Fig. 9 shows the coupling device composed of the body 5 and the ring 47 and having a corrugated tube 3 inserted therein. The tube is blocked in the coupling device by the two tongues 57 of the ring 47 which extend through corresponding openings 15 of the body 5 for engagement of the engagement ribs 59 in a peripheral groove of the corrugated tube 3. When exerting a pulling force on the corrugated tube 3 the ring 47 will move upward, as viewed in Fig. 9, whereby the projection 65 at the free end of each tongue 57 will become located under the wall of the housing 5 and will block the tongue 57. If the ring 47 is manually pushed downward, as viewed in Fig. 9, its convex rounded cam surface 61 will slide upon the convex rounded shoulder 23' of the housing 5 whereby the tongue 57 will be pivoted outwardly and the corrugated tube will be released.

The end of the corrugated tube 3 is received in the groove 37 of the annular seal 33.

Claims

CLAIMS 1. A coupling device for corrugated tubes, comprising a tubular body (5) for receiving the corrugated tube (3), a ring (7, 7) mounted to tube body (5) for axial displacement, and at least one flexible tongue (17, 57) integral with the ring and extending in the axial direction and carrying a radially projecting engagement rib (19) for engagement into a peripheral groove of the corrugated tube (3), said body (5) comprising a window-like opening (15) for each said tongue (17, 57) for permitting radially outward movement of the tongue (17, 57) for releasing the corrugated tube (3), c h a r a c t e r i z e d in that said ring (7, 47) encircles the body (5) and is mounted to the outer periphery of the body (5), each said tongue (17, 57) extending through a corresponding opening t15) from the outer to the inner periphery of the body (5) for cooperation with the corrugated tube (3), and each tongue (17, 57) being formed at its radially interior side with a cam surface (21, 61) adapted for engagement with a shoulder (23, 23') of the body (5), wherein axial displacement of the ring (7, 47) in a first axial direction will bring said cam surface (21, 61) into engagement with said shoulder (23) for exerting a radial force component onto the tongue (17, 57) to flex the tongue (17, 57) outwardly and thereby move the engagement rib (19, 59) of the tongue (17, 57) out of the groove of the corrugated tube (3) for releasing the tube.
2. A coupling device as claimed in claim 1, wherein each tongue (17, 57) extends from said ring (7, 47) in that axial direction which is opposed to the direction of insertion of the corrugated tube (3), and wherein said first axial direction for displacement of the ring (3) corresponds to the direction of insertion of the corrugated tube (3)
3. A coupling device as claimed in claim 1, wherein said cam surface (2i, 61) is inclined or has a convex rounded shape.
4. A coupling device as claimed in claim 1, wherein said shoulder (23, 23') of the body (5) has its radially outward facing face inclined or convex shaped.
5. A coupling device as claimed in claim 1, wherein each tongue (17) is formed with a locking projection (25) which can be moved by axial displacement of the ring (7) in a second axial direction into engagement below a radially inwardly directed locking surface (27) of the body (5), for locking the tongue (17, 57) against flexing in the outward radial direction.
6. A coupling device as claimed in claim 5, wherein co-operating engagement faces of said locking projection (25) of the tongue (17, 57) and/or said locking face (27) of the body (5) are inclined.
7. A coupling device for receiving an end of a corrugated member comprising a tubular body for receiving therein an end of a corrugated member and a coupling member axially displaceable relative to the tubular body and having at least one projection extending through an or a corresponding opening in the tubular body so as to engage with a corrugation of a corrugated member when the member is inserted into the tubular body, the at least one projection and the or the corresponding opening cooperating so that, when the end of a corrugated member is received in the body, axial displacement of the coupling member relative to the body causes the at least one projection to move out of engagement with a corrugation of the corrugated member to enable the corrugated member to be removed from the coupling device.
8. A coupling device having the features recited in any one or any combination of the preceding claims.
9. A coupling device substantially as hereinbefore described with reference to Figures 1 to 4 or 5 to 9 of the accompanying drawings.
10. A corrugated tube or member having a coupling device in accordance with any one of the preceding claims.