METHOD FOR ASSEMBLING A SEALING RING ON AN ELECTRIC MOTOR FOR MOTOR PROPULSION OF AN AUTOMOBILE

Abstract

The invention relates to a method for mounting a sealing ring (1) of an electric motor comprising a metal housing, a sleeve fitted into the housing and the ring, the method employing a mounting tool (6) comprising a radially extendable locking portion (7) actuable between a retracted and an extended configuration and a support portion (8) for the ring, the method providing for placing the ring on the support portion, inserting the locking portion into the conduit and extending it, heating the housing, inserting the sleeve equipped with the tool and the ring into the housing, allowing the housing to cool, and retracting the locking portion to remove the tool. The invention also relates to a tool (6) for use in such a method and a ring (1) for mounting by such a method. Figure 2

Description

Title of the invention: METHOD FOR ASSEMBLING A SEAL RING ON AN ELECTRIC MOTOR MOTOR VEHICLE PROPULSION

[0001] The invention relates to a method of mounting a sealing ring of an electric propulsion motor of an automobile, a mounting tool used in such a method and said ring.

[0002] It is known to mount a sealing ring on an electric propulsion motor of a motor vehicle, said motor comprising: - a metal casing, - a stator comprising a sleeve, defining a cylindrical conduit, and a plurality of coils of conductive wire mounted inside said sleeve and having a protruding part extending from said sleeve and forming in axial view within a circle, said sleeve being fitted in tight contact within said housing, - said ring, made of molded plastic material, covering the said protruding part on the outside.

[0003] One way of achieving the tight contact between the housing and the sleeve is hot shrink fitting, which consists of heating said housing so as to expand it, inserting said sleeve into said housing, then allowing said housing to cool so that it contracts and ensures a tight fit of said sleeve into said housing.

[0004] A known way of mounting the ring is to do so once the sleeve is fitted into the housing.

[0005] However, constraints related to the geometry of the engine may make such a method impractical.

[0006] One way of proceeding could be to insert the ring into the housing once heated, and then insert the sleeve into it.

[0007] However, given the high temperature involved in achieving the expansion of the casing, such a method proves complicated, as a manufacturing operator cannot do it manually.

[0008] The invention aims to provide a method for mounting the sealing ring in a safe and ergonomic manner for the manufacturing operator.

[0009] To this end, and according to a first aspect, the invention proposes a method for mounting a sealing ring of an electric motor for the propulsion of a motor vehicle, said motor comprising: - a metal casing, - a stator comprising a sleeve, defining a cylindrical conduit, and a plurality of coils of conductive wire mounted inside said sleeve and having a protruding part extending from said sleeve and forming in axial view within a circle, said sleeve being fitted in tight contact within said housing, - said ring, made of molded plastic material, covering the said protruding part on the outside said method involving the use of a tool for mounting said ring, said tool comprising: - a radially extensible friction-locking portion for said tool in said conduit, said locking portion being actuable between a radially retracted configuration and a radially deployed configuration, - and a supporting part of said ring; said process includes the following steps: - place the said ring onto the said support part, - insert, along a first axial direction, said anchoring part in its retracted configuration into said conduit until said ring is peripherally supported on an edge of said sleeve - activate said blocking component in its deployed configuration so as to block said tool in said conduit, - heat the said crankcase in order to expand it, - insert said stator, equipped with said tool and said ring, into said housing in a second axial direction, opposite to said first direction, until said ring is brought into peripheral contact with a ring projecting radially inwards provided in said housing, - allow the said casing to cool so that it contracts and ensures a tight fit of the said sleeve, - actuate said locking part in retracted configuration, - remove said tool from said conduit.

[0010] It is specified here that, throughout the description, the circular locating terms (axial, radially, etc.) are taken with reference to the axis of rotation of the motor (reference X on the figures), corresponding in this case to the axis of symmetry of the sleeve.

[0011] With such a process, the assembly of the sealing ring is carried out in a safe and ergonomic manner for the manufacturing operator.

[0012] According to another aspect, the invention provides a tool intended for use in such a process, said tool comprising: - a radially extendable locking section that can be actuated between a radially retracted configuration and a radially deployed configuration, - and a support part for a sealing ring.

[0013] According to one embodiment, the blocking part comprises - a base having a first sector in the shape of a circular arc intended, when the tool is inserted into the conduit, to conform to the shape of said conduit and a second sector intended to be moved away from said conduit - said second sector is provided with a locking blade actuated radially outwards by a spring, so as to put said locking part in deployed configuration, said blade cooperating with a cam allowing it to be actuated radially inwards, so as to put said locking part in retracted configuration.

[0014] According to one embodiment: - the cam is mounted for rotation by means of a first axial finger sliding in a first radially elongated slot provided in the base - the blade is mounted to slide radially by means of a second axial finger integral with said base and radially extended outwards from said first slot, said second finger sliding in a second radially elongated slot provided in said blade, said blade further being provided with a receiving orifice for said first finger, said cam bearing against said second finger - the spring is a spiral tension spring mounted between said fingers.

[0015] According to one embodiment, the blocking part and the support part are connected to each other by a connecting rod extending axially, so as to keep them at a distance from each other.

[0016] The invention finally proposes a sealing ring intended to be mounted by such a method, said ring being provided with a plurality of tabs projecting radially inwards intended to be received by a plurality of respective receiving zones provided on the support part.

[0017] According to one embodiment, the ring is provided with two annular seals made of elastomer material intended to ensure sealing at the edge of the sleeve and at the crown.

[0018] According to one embodiment, the legs are provided with axial projections intended to allow the ring to be locked in the nominal angular position.

[0019] The invention will be further detailed by describing non-limiting embodiments, and based on the accompanying figures illustrating variants of the invention, in which: - [Fig.1] is a schematic representation in partial axial section of a motor during assembly, with the sealing ring mounting tool positioned in the sleeve conduit and the locking part in the deployed configuration. - [Fig.2] is a schematic perspective representation of a tool assembly of a sealing ring according to an embodiment, in exploded view (A) and in non-exploded view with representation of the ring mounted on the support part of said tool (B).

[0020] A method for mounting a sealing ring 1 of an electric propulsion motor of a motor vehicle is now described with reference to the figures, said motor comprising: - a metal casing 2, - a stator comprising a sleeve 3, defining a cylindrical conduit 4, and a plurality of coils of conductive wire mounted inside said sleeve and having a protruding part 5 extending from said sleeve and forming in axial view within a circle, said sleeve being fitted in tight contact within said housing, - said ring, made of molded plastic material, covering the said protruding part on the outside, said method involving the use of a tool 6 for mounting said ring, said tool comprising: - a radially extensible locking portion 7 for friction-operated locking of said tool in said conduit, said locking portion being actuable between a radially retracted configuration and a radially deployed configuration, - and a support portion 8 of said ring, said method comprising the following steps: - placing said ring on said support portion, - inserting said anchor portion in a retracted configuration into said conduit in a first axial direction SI until said ring is peripherally supported on an edge 9 of said sleeve, - activate said blocking component in its deployed configuration so as to block said tool in said conduit, - heat the said crankcase in order to expand it, - insert said stator, equipped with said tool and said ring, into said housing along a second axial direction S2, opposite to said first direction, until said ring is brought into peripheral contact with a ring 10 projecting radially inwards provided in said housing, - allow the said casing to cool so that it contracts and ensures a tight fit of the said sleeve, - activate the said locking part in its retracted configuration, - remove said tool from said conduit, in particular in the said first direction.

[0021] A tool 6 for use in such a process is now described, said tool comprising: - a radially extendable locking part 7 that can be actuated between a radially retracted configuration and a radially deployed configuration, - and a support part 8 of a sealing ring 1.

[0022] According to the embodiment shown, the blocking part 7 comprises: - a base 11 having a first sector 12 in the form of an arc of a circle intended, when the tool 6 is inserted into the conduit 4, to conform to the shape of said conduit and a second sector 13 intended to be moved away from said conduit, - said second sector is provided with a locking blade 14 actuated radially outwards by a spring 15, so as to put said locking part in deployed configuration, said blade cooperating with a cam 16 allowing it to be actuated radially inwards, so as to put said locking part in retracted configuration.

[0023] According to the embodiment shown: - the cam 16 is mounted for rotation by means of a first axial finger 17 sliding in a first radially elongated slot 18 provided in the base 11, - the blade 14 is mounted to slide radially by means of a second axial finger 19 attached to said base and radially extended outwards from said first slot, said second finger sliding in a second radially elongated slot 20 provided in said blade, said blade further being provided with an orifice 21 for receiving said first finger, said cam bearing against said second finger, - spring 15 is a spiral tension spring mounted between said fingers.

[0024] According to the embodiment shown, the locking part 7 and the support part 8 are connected to each other by a connecting rod 22 extending axially, so as to keep them at a distance from each other.

[0025] Finally, a sealing ring 1 intended to be mounted by such a method is described, said ring being provided with a plurality of tabs 23 projecting radially inwards intended to be received by a plurality of respective receiving zones 24 provided on the support part 8.

[0026] It is observed that with such an arrangement, the removal at the end of assembly of the tool 6 from the conduit 4 requires imparting an axial rotation to said tool in order to disengage the tabs 23 from the receiving areas 24.

[0027] According to the embodiment shown, the ring 1 is provided with two annular seals 25 - here nested - made of elastomer material intended to ensure sealing at the level of the edge 9 of the sleeve 3 and at the level of the crown 10.

[0028] According to the embodiment shown, the legs 23 are provided with axial projections 26 intended to allow the ring 1 to be locked in the nominal angular position.

Claims

Demands

1. A method for mounting a sealing ring (1) of an electric motor for the propulsion of a motor vehicle, said motor comprising: - a metal casing (2), - a stator comprising a sleeve (3), defining a cylindrical conduit (4), and a plurality of coils of conductive wire mounted inside said sleeve and having a protruding part (5) extending from said sleeve and forming in axial view within a circle, said sleeve being fitted in tight contact within said housing, - said ring, made of molded plastic material, covering the said protruding part on the outside, said method being characterized in that it provides for the implementation of a tool (6) for mounting said ring, said tool comprising: - a radially extensible locking portion (7) by friction of said tool in said conduit, said locking portion being actuable between a radially retracted configuration and a radially deployed configuration, - and a support portion (8) of said ring, said method comprising the following steps: - placing said ring on said support portion, - inserting said anchor portion in a retracted configuration in a first axial direction (SI) into said conduit until said ring is peripherally supported on an edge (9) of said sleeve, - actuate said locking part in deployed configuration so as to lock said tool in said conduit, - heat said casing so as to expand it, - insert said stator, equipped with said tool and said ring, into said housing in a second axial direction (S2), opposite to said first direction, until said ring is brought into peripheral contact with a ring (10) projecting radially inwards provided in said housing, - allow the said casing to cool so that it contracts and ensures a tight fit of the said sleeve, - actuate said locking part in retracted configuration, - remove said tool from said conduit.

2. Tool (6) intended to be used in a process according to claim 1, characterized in that it comprises: - a radially extensible locking part (7) actuable between a radially retracted configuration and a radially deployed configuration, - and a support part (8) for a sealing ring (1).

3. Tool (6) according to claim 2, characterized in that the locking part (7) comprises: - a base (11) having a first sector (12) in the shape of an arc of a circle intended, when the tool is inserted into the conduit (4), to conform to the shape of said conduit and a second sector (13) intended to be moved away from said conduit, - said second sector is provided with a locking blade (14) actuated radially outwards by a spring (15), so as to put said locking part in the deployed configuration, said blade cooperating with a cam (16) allowing it to be actuated radially inwards, so as to put said locking part in the retracted configuration.

4. Tool (6) according to claim 3, characterized in that: - the cam (16) is mounted to rotate by means of a first axial finger (17) sliding in a first radially elongated slot (18) provided in the base (11), - the blade (14) is mounted to slide radially by means of a second axial finger (19) fixed to said base and radially extended outwards from said first slot, said second finger sliding in a second radially elongated slot (20) provided in said blade, said blade further being provided with an orifice (21) for receiving said first finger, said cam bearing on said second finger, - the spring (15) is a spiral tension spring mounted between said fingers.

5. Tool (6) according to any one of claims 2 to 4, characterized in that the locking part (7) and the support part (8) are connected to each other by a connecting rod (22) extending axially, so as to keep them apart from each other.

6. Sealing ring (1) intended to be mounted by a method according to claim 1, characterized in that it is provided with a plurality of tabs (23) projecting radially inwards for receiving by a plurality of respective receiving zones (24) provided on the part of

7. support (8). Ring (1) according to claim 6, characterized in that it is provided with two annular seals (25) made of elastomeric material intended to ensure sealing at the edge (9) of the sleeve (3) and at the

8. the crown (10). Ring (1) according to any one of claims 6 or 7, characterized in that the lugs (23) are provided with axial projections (26) intended to allow locking of said ring in nominal angular position.

Images