FR3006030A1 - CONNECTING DEVICE AND METHOD FOR CHANNEL TUBE - Google Patents

Abstract

Tube connecting device having an end portion provided with an outer chamfer, comprising a tubular body internally provided with an annular sealing element and a hooking member to ensure a tight holding of the portion of end of the tube in the body. The device comprises at least one retractable abutment arranged to oppose insertion into the body of a non-chamfered tube end portion and for the chamfer to form a retraction cam of the abutment when the portion end of chamfered tube is introduced into the body. Corresponding connection method.

Description

The present invention relates to fluid transport circuits such as a thermal control circuit. The invention more particularly relates to a device and a connection method for chanterled tube. A fluid transport circuit generally comprises tubes connected to each other by connecting devices to which end portions of these tubes are connected.

A connecting device comprises a tubular body internally provided with an annular sealing element and a fastening member to ensure a sealed retention of the end portion of the tube in the body. The body comprises a central tubular appendix on which the tube end portion is to be engaged, the sealing member being mounted on said appendix to be compressed between an outer surface of the appendix and an inner surface of the end portion of tube. This arrangement prevents the fluid from coming into contact with the tube end, which, in the case of a rolled tube, could cause delamination thereof. During installation, the tubes must be cut to the correct lengths. At the installation site, this cut is made using a cutter-type pipe cutter. This cutting mode causes a crushing of the end portion of the tube which keeps some ovalization after cutting. Such ovalization makes it difficult to obtain a continuous contact of the sealing element on the end portion of the tube so that it is necessary to give a circular section to the tube end portion before its connection. To do this, a shaping tool is inserted into the tube end which will also make an inner chamfer facilitating insertion of the body appendage into the tube end portion. There are conformation tools that perform an outer chamfer in addition to the inner chamfer. However, it happens that the operator responsible for the installation fails to conform one of the end portions before proceeding to its connection. The risk of leakage is then very important either from the pressurization of the circuit, or later. An object of the invention is to provide a means of limiting the risk of a tube being connected with ovalization. For this purpose, there is provided, according to the invention, a tube connecting device having an end portion provided with an outer chamfer. The device comprises a tubular body internally provided with an annular sealing member and a fastening member for sealingly securing the end portion of the tube in the body. The device comprises at least one retractable abutment arranged to oppose insertion into the body of a non-chamfered tube end portion and for the chamfer to form a retraction cam of the abutment when the portion end of chamfered tube is introduced into the body.

The invention therefore imposes the use of conformation tools that provide an outer chamfer in addition to the inner chamfer. If the tube end portion has been shaped, its ovality has been corrected and has an outer chamfer. Upon introduction of the end portion of the tube into the device, the outer chamfer serves as a cam causing the retraction of the stop which releases the passage for the end portion of the tube and allows the connection. If the tube end portion has no outer chamfer, it can not be assured that it has been shaped. As it has no outer chamfer, it abuts against the stop which does not retract and prohibits the connection. The invention also relates to a method of connecting a tube to a connecting device, comprising the steps of: - arranging on the device a retractable stop allowing the introduction of only a tube end portion chamfered externally; - cut the tube to length; - Completing an end portion of the tube giving it if necessary a circular section and making at least one outer chamfer; - Introduce the end portion of the tube in the connecting device. Other features and advantages of the invention will emerge on reading the following description of particular non-limiting embodiments of the invention.

Reference is made to the accompanying drawings, in which: - Figure 1 is a perspective view with an axial section of a connecting device according to a first embodiment; - Figures 2a., 2b. and 2c. are partial views in longitudinal section respectively showing an attempt to connect a non-chamfered tube end portion, the beginning of introduction of a chamfered tube end portion and the continuation of the introduction of a chamfered tube end portion; - Figure 3 is a partial longitudinal sectional view of a connection device according to a first variant of the first embodiment; - Figure 4 is a partial longitudinal sectional view of a connecting device according to a second variant of the first embodiment; - Figure 5 is a partial longitudinal sectional view of a connecting device according to a third variant of the first embodiment; FIG. 6 is a partial longitudinal sectional view of a connection device according to a second embodiment; FIG. 7 is a fragmentary longitudinal detail view of the connecting device according to the second embodiment, after connection of a tube end portion; - Figure 8 is a view similar to Figure 6 of a connection device according to a third embodiment. With reference to the figures, the connecting device according to the invention is intended for the connection of tubes 100 having an end portion provided with an outer chamfer 101. The end portion here also comprises an inner chamfer 102 but this is not mandatory in connection with the invention. The connecting device may be of the union type, a T-piece, a Y-connector, a stitching or the like. Both ends of the device may be connected to tubes or to a tube and to a circuit element such as a pump, actuator, dispenser or the like. With reference to FIGS. 1 and 2, the connection device according to the first embodiment comprises a tubular body 1 in which a staged housing, generally designated 2, is formed comprising an inlet section 2.1 and a terminal section 2.2. connected to the inlet section 2.1 via a shoulder 2.3. In the inlet section 2.1 is fixed a tubular insert 3 in two parts trapping a washer 4 for hooking the end portion of the tube and receiving a slider 5. The terminal section 2.2 is arranged to receive the end portion of the tube end portion 100.

The washer 4 is an elastically deformable washer having an inner periphery divided into a plurality of teeth and having a rest state in which the teeth define a passage section smaller than an outer section of the tube end portion 100 and a deformed state in which the passage section defined by the teeth is equal to or greater than the outer section of the tube end portion 100. The pusher 5 is tubular and defines a passage section of the end portion of the tube 100. The pusher 5 is movable between a first position in which it leaves the washer 4 to retain the tube end portion 100 and a second position in which it prevents the washer 4 from ensuring the retention of the portion of the tube. end of tube 100. The pusher 5 has, opposite the washer 4, a first projecting end of the body 1 allowing the actuation of the pusher 5 from its first position towards its end. second position and, on the side of the washer 4, a second end arranged to lift the teeth of the washer 4 when the pushbutton 5 is in its second position. The device comprises two retractable stops 6 arranged to oppose insertion into the body 1 of a non-chamfered tube end portion and for the outer chamfer 101 to form a cam for retracting the abutments 6 when the end portion of chamfered tube 100 is introduced into the body 1. The stops 6 are secured to the first end of the pusher 5 opposite the washer 4. More specifically, the stops 6 have the form of tabs arranged in the internal wall of the first end of the pusher 5 to extend substantially axially by having a downstream end secured to the pusher 5 and a free upstream end extending in internal projection in the passage section defined by the pusher 5 ("downstream" and "Upstream" refers to the direction of introduction of the tube end portion into the device). The body 1 comprises a central tubular appendix 7 extending coaxially and in axial projection in the stepped housing 2 and on which the tube end portion 100 is intended to be engaged. Two sealing elements are mounted on said central tubular appendix 7 to be compressed between an outer surface of the central tubular appendix 7 and an inner surface of the tube end portion 100.

To connect a tube to the connection device, it is necessary to: - cut the tube to length; - Shape the end portion of cut tube 100 giving it if necessary a circular section and making at least one outer chamfer 101; - Introduce the tube end portion 100 in the connecting device. We see in Figures 2b. and 2c. the outer chan- tor 101 forms a cam for retraction of the abutments 6 when the chamfered tube end portion 100 is introduced into the body 1. In contrast, FIG. 2a shows that a tube end portion 200 devoid of external chamfer abuts against the stops 6 without being able to retract them. In the first variant of FIG. 3, the stops 6 extend in axial recess from an additional annular surface 9 for guiding the tube end portion 100, said additional annular guide surface 9 extending axially upstream of the abutments 6 with reference to a direction of insertion of the tube end portion 100 into the device. In the second variant of FIG. 4, the stops 6 are no longer secured to the first end of the pusher 5 but to a central part of the pusher 5. The portion of the pusher extending between the first end thereof and the free end of the abutments 6 forms a guide surface of the tube end portion 100 before it meets the abutments 6. In the third variant of FIG. 5, the abutments 6 no longer extend axially but circumferentially. . More specifically, the stops 6 have the form of tabs formed in the inner wall of the central portion of the pusher 5 to extend substantially along the circumference of the pusher 5 having an end secured to the pusher 5 and a free end s' extending in internal projection in the passage section defined by the pusher 5. It is understood that the tube end portion 100 no longer bears against the end face of the tabs but against the upstream side face thereof ("upstream Refers to the direction of introduction of the end portion of tube 100 in the device).

With reference to FIGS. 6 and 7, and according to the second embodiment, the body 1 has no appendix 7. A first annular sealing element 61 is housed in the inlet section 2.1 between the shoulder 2.3 and the insert 3. The first sealing member 61 is thus arranged to be compressed between an axial wall of the inlet section 2.1 and an outer surface of the tube end portion 100. A second annular sealing element generally referred to as 62 is housed in the end section 2.2 bearing against substantially radial walls 2.4 which extend downstream of the second annular sealing element 62 with reference to a direction of insertion of the end portion of tube 100 in the device and which are formed by rib ends 2.5 of the body 1 extending axially in the terminal section 2.2. The second sealing element 62 comprises an annular main portion 62.1 having an axial projecting inner periphery which extends a tubular sleeve 62.2 arranged to be applied against an annular portion of the inner surface of the end portion of the tube 100, here the internal chamfer 101, when the main portion of the sealing element is compressed between the substantially radial walls 2.4 and the front surface of the tube end portion 100. It will be noted that due to the space between the ribs 2.5, the fluid pressure can be exerted behind the annular main portion 62.1 to further flatten the annular main portion 62.1 against the front surface of the tube end portion 100 and the tubular sleeve 62.2 against the inner bevel 102 (The principle of such operation has been described in particular in document FR-A-2941027). Also preferably for this purpose, the radial walls 2.4 are inclined such that the compressive force exerted by the end surface of the end portion of the tube 100 on the second sealing member 62, upon introduction. of the end portion of the tube 100, tends to apply the tubular sleeve 62.2 against the inner chamfer 102.

This embodiment is particularly interesting because the minimum passage section is only slightly smaller than the inner section of the tube. With reference to FIG. 8 and according to the third embodiment, the body of the device is substantially identical to that of the first embodiment, but the device comprises, in place of the washer 4, an attachment member 40 of clamp type in one piece with the pusher 5, the latching member 40 forming the second end of the pusher 5. The pusher 5 is for the rest identical to that of Figure 3. Of course, the invention is not not limited to the embodiments described but encompasses any variant within the scope of the invention as defined by the claims.

In particular, the body of the device may have another shape than that described. The number and shape of the sealing elements can be changed. The ribs 2.5 may be replaced by a bulge in which has been provided a fluid supply channel behind the sealing member 62. The device may not include pusher. The number, shape and position of the stops can be changed.

The stop may be integral with the body or the insert in the absence of pusher.

Claims (11)

REVENDICATIONS1. Tube connecting device having an end portion provided with an outer chamfer, comprising a tubular body internally provided with an annular sealing element and a hooking member to ensure a tight holding of the portion of end of the tube in the body, characterized in that the device comprises at least one retractable stop arranged to oppose insertion into the body of a non-chamfered tube end portion and that the chamfer forms a retraction cam of the abutment when the chamfered tube end portion is introduced into the body. 2. Device according to claim 1, com- prizing a tubular disconnecting pusher, coaxial with the annular sealing element, which defines a passage section of the tube end portion and which is movable between a first position in which it leaves the latching member to ensure the retaining and a second position in which it prevents the latching member to ensure retention, the pusher having a first end opposite to the latching member and arranged to be able to operate the pusher from its first position to its second position, and the stop being solidary of the pusher. 3. Device according to claim 2, wherein the fastening member and the pusher are in one piece, the fastening member forming a second end of the pusher. 4. Device according to claim 2, wherein the attachment member is a deformable washer having an inner periphery divided into a plurality of teeth, the pusher having a second end arranged to lift the teeth when the pusher is in that second position. 5. Device according to claim 2, wherein the stop is secured to the first end of the pusher. The device of claim 1, wherein the sealing member is received in a housing of the body to be compressed between an axial wall of the housing and an outer surface of the tube end portion. The device of claim 1, wherein the sealing member is received in a housing of the body to be compressed between a radial wall of the housing and a front surface of the tube end portion. 8. Device according to claim 7, wherein the sealing element comprises an annular main portion having an inner projecting axial periphery of which extends a tubular sleeve arranged to be applied against an annular portion of internal surface. of the end portion of the tube when the main portion of the sealing member is squeezed between the radial wall of the housing and the end surface of the tube end portion. The device according to claim 1, wherein the body comprises a central tubular appendix on which the tube end portion is to be engaged, the sealing member being mounted on said appendix to be compressed between a outer surface of the appendix and an inner surface of the end portion of the tube. 10. Device according to claim 1, wherein the abutment extends in axial recess from an additional annular surface for guiding the tube end portion, said additional annular guide surface extending upstream of the abutment by reference to a direction of introduction of the end portion of the tube into the device. 11. A method of connecting a tube to a connecting device, comprising the steps of: - providing on the device a retractable stop allowing the introduction of only an end portion of externally chamfered tube; - cut the tube to length; - Completing an end portion of the tube giving it if necessary a circular section and making at least one outer chamfer; - Introduce the end portion of the tube in the connecting device.