Motorized device comprising a member with eccentric movement

Abstract

A motorized device includes a member performing an eccentric movement coupled to an electric motor via a torque-transmission means including two tubular integral portions coupled by an interlocking connection. The first integral portion has a first cylindrical segment supporting the rotor of the motor, and a second cylindrical segment supporting a rear bearing, these segments being coaxial with a first longitudinal axis. The second integral portion has a cylindrical segment supporting a front bearing having an outer diameter coaxial with the first longitudinal axis, and a cylindrical drive segment, which is eccentric with respect to this longitudinal axis, having an outer diameter. The two integral portions are coupled by an interlocking connection including a male guide segment extending one of the integral portions, engaged in a hollow female guide segment.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application is a national phase entry under 35 U.S.C. § 371 of International Patent Application PCT / EP2024 / 060784, filed Apr. 19, 2024, designating the United States of America and published as International Patent Publication WO 2024 / 223443 A1 on Oct. 31, 2024, which claims the benefit under Article 8 of the Patent Cooperation Treaty of European Patent Office Application Serial No. 23169599.0, filed Apr. 24, 2023, and of French Patent Application Serial No. FR2304856, filed May 16, 2023.TECHNICAL FIELD

[0002] The present disclosure relates to the field of electrical devices formed by an eccentric member driven by an electrical machine.BACKGROUND

[0003] Driving an eccentric member generates high mechanical stresses due to the asymmetries of the rotary masses, especially on the coupling of the motor axle and the driven member.

[0004] A non-limiting example of such devices is a scroll-type compressor consisting of two spirals, one fixed, the other in orbital movement, which creates the compression, the suction chamber is located around the two spirals, and the discharge is located in the center, where the gas escapes through a hole.

[0005] Vane compressors are another example of such electrical devices with eccentric movement. The principle consists of a cylindrical stator (housing) with a radial inlet and outlet, in which an eccentrically-mounted circular rotor rotates. The rotor or stator is equipped with slots in which the vanes can slide radially. When the rotor rotates, the vanes ensure the closure of the gap between the stator wall and the rotor wall. A gap then forms between the stator wall, the two vanes and the rotor, which narrows as the rotor rotates toward the compressed air outlet.

[0006] Motors associated with hypocycloid gearboxes consist of another example of devices with an eccentric member, as well as epicycloidal gear trains.

[0007] In the state of the art, devices are known implementing a single drive shaft directly controlling the orbital movement of the eccentric member.

[0008] U.S. Pat. No. 5,040,958 describes a scroll compressor comprising a stationary scroll element comprising a stationary end plate and a stationary spiral wrap extending from the stationary end plate; an orbiting scroll element comprising an orbiting end plate and an orbiting spiral wrap extending from the orbiting end plate that orbits about the axis of the stationary scroll member and has an orbital bearing, the wraps of the stationary scroll member and the orbiting scroll member engaging with each other to form a fluid compressing chamber;

[0009] An anti-rotating device for preventing the orbiting scroll member from rotating on its own axis and permits the orbiting scroll member to orbit around the axis of the stationary scroll member. A main shaft rotatable on its own axis and having a pivot pin incorporating an axis spaced from the axis of the main shaft. An eccentric drive shaft having an axis spaced from the axis of the main shaft and orbital about the axis of the main shaft, the eccentric drive shaft being able to be engaged rotationally with the orbiting bearing so as to enable the eccentric drive shaft to drive the orbiting scroll member about the axis of the stationary scroll member, the eccentric drive shaft comprising a pivot bearing having an axis spaced from the axis of the eccentric drive shaft and being able to be rotationally engaged with the pivot pin so that the eccentric drive shaft rotates about the axis of the pivot pin, a distance between the axis of the eccentric drive shaft and the axis of the main shaft is adapted to be changed, and the main shaft drives the eccentric drive shaft to orbit about the axis of the main shaft. The rotational moment generated by the centrifugal force of the balance weight draws the eccentric drive shaft toward the main shaft; limiting means for limiting a range of orbital movement of the eccentric drive shaft about the axis of the pivot pin, a distance between the limiting means and the axis of the main shaft is larger in a direction of a line extending between the axis of the main shaft and the axis of the eccentric drive shaft than a distance between the axis of the main shaft and the axis of the pivot pin.

[0010] European Patent Application Publication No. 2,636,903 A2 describes a rotary compressor comprising a housing, a cylinder, a rotating shaft, a roller and an eccentric cam. The cylinder can be installed inside the housing and configured to provide a space for compressing the gas. The rotating shaft can be arranged to pass through the cylinder. The roller can be configured to compress gas by rotating along an inner circumferential surface of the cylinder. The eccentric cam can be integrally formed with the rotary shaft and arranged inside the roller. The eccentric cam can be arranged at an eccentric position in a shaft direction on an axial line of the rotary shaft.

[0011] The solutions of the prior art have several drawbacks. Solutions providing for a single, integral axle with an eccentric end involve complex operations for assembling and disassembling the axle. These solutions are not easy to repair.

[0012] They also involve long, costly and complex machining operations: machining the raw bar will generate a large quantity of swarf, especially through the considerable span length to be performed (machining, number of passes, hardening, grinding).

[0013] Assembly is complicated: the single axle receives a bearing at each end and a bundle of rotor laminations in the center, it is then integrated into the system frame through the stator pre-assembled in the main housing, the rear bearing carrying the axle engaging in the main housing. The front bearing is supported by a secondary housing (compressor compartment) attached to the main housing. This type of assembly is highly restrictive in terms of the size and dimensions of the bearings (which must be able to pass through the stator, and therefore be smaller than its internal diameter) on the one hand, and the implementation of balance means and weights on the other.

[0014] In addition, single-axle solutions pose a problem for the insertion of a printed drive circuit board of the motor, unless a slot is provided to slide the printed circuit board about the axle, which reduces the surface available on the PCB. These prior art solutions mean that the control electronics must be located at the rear of the system, leading to a larger volume, greater distance between the motor and the electronics (and therefore greater complexity and cost for the electrical connections to the stator and the position / speed sensor function), and the need to provide a specific liquid cooling circuit for the electronics at the rear.BRIEF SUMMARY

[0015] In order to solve the disadvantages of the background art, the present disclosure relates in its most general sense to a device comprising a member performing an eccentric movement coupled to an electric motor, wherein the eccentric member is driven by the electric motor via a torque-transmission means consisting of two tubular integral portions coupled by an interlocking connection.

[0016] The first integral portion having:

[0017] a first cylindrical segment supporting the rotor of the electric motor having an outer diameter Dr,

[0018] a second cylindrical segment supporting a rear bearing having an outer diameter Db, and

[0019] the segments being coaxial.

[0020] The second integral portion having:

[0021] a cylindrical segment supporting a front bearing having an outer diameter Da coaxial with the segments of the first portion, and

[0022] a cylindrical drive segment, which is eccentric with respect to the longitudinal axis, having an outer diameter De.

[0023] The two integral portions being coupled by an interlocking connection consisting of:

[0024] a male guide segment of outer diameter Dc and of length LINTERLOCKING extending one of the integral portions (110, 150), engaged in a hollow female guide segment (115) of depth Lc provided in the other of the portions, where Lc is greater than or equal to 1.5 times Dc, and

[0025] the two integral portions further comprising at least one angular and axial locking means.

[0026] According to variants:

[0027] the first integral portion further has an additional cylindrical segment supporting a sensor having an outer diameter Ds coaxial with the longitudinal axis,

[0028] the first integral portion further has an additional cylindrical segment supporting a rear balance weight having an outer diameter Dm coaxial with the longitudinal axis,

[0029] the first integral portion further has an annular shoulder adjacent to the cylindrical segment supporting the rotor of the electric motor, for the axial positioning of the rotor,

[0030] the second portion further has an additional cylindrical segment supporting a front balance weight having an outer diameter DM, the additional segment being coaxial with the longitudinal axis when the two portions are coupled,

[0031] the second portion further has an additional cylindrical segment matching the passage of the wall separating the motor from the driven member having an outer diameter Da,

[0032] the motor comprises a printed circuit board arranged transversely between the rotor (220) and the second bearing, the printed circuit board having a passage through which the torque-transmission means passes,

[0033] the one or more segments passing through the passage of the printed circuit board have the smallest diameters,

[0034] the sensor-carrying segment is the segment closest to the printed circuit board,

[0035] at least one of the first and second portion is hollow, except the front walls of the male and female guide segments,

[0036] the angular locking means consists of cooperating torque-transmission flat surfaces,

[0037] the axial locking means consists of an axial screw connecting the male guide segment and the female guide segment, the axial end of the male guide segment having an axial thread and the bottom of the female guide segment having a bore for the passage of the screw ensuring the axial end of the male guide segment is blocked against the bottom of the female guide segment,

[0038] the device comprises a first casing cooled by fluid circulation, the first casing comprising the electric motor, and a second casing cooled by fluid circulation, comprising the eccentrically driven member, and wherein the fluid circulation circuits of the two casings open onto adjacent faces in alignment when the casings are joined together,

[0039] comprises an intermediate casing comprising at least two fluid connections opening on one side at the fluid connections of the first casing and on the other side at the fluid connections of the second casing,

[0040] the intermediate casing comprises at least two fastening means, and

[0041] the intermediate casing comprises at least one lifting eyelet.BRIEF DESCRIPTION OF THE DRAWINGS

[0042] The present disclosure will be better understood from reading the following description, which relates to a non-limiting exemplary embodiment illustrated by the accompanying drawings, in which:

[0043] FIG. 1 depicts an overview of the motorization, in a front three-quarter perspective cross-sectional view of an exemplary embodiment of a scroll compressor according to the present disclosure,

[0044] FIG. 2 depicts an exploded view of an exemplary embodiment of a torque-transmission means, equipped with two integral portions, for a compressor according to the present disclosure,

[0045] FIG. 3 depicts a cross-sectional view of the first integral portion of a torque-transmission means according to the present disclosure,

[0046] FIG. 4 depicts a cross-sectional view of the second integral portion of a torque-transmission means according to the present disclosure, in a perspective view of an exemplary embodiment of a compressor according to the present disclosure,

[0047] FIG. 5 depicts an overview of the motorization, in an exploded front three-quarter perspective view of an exemplary embodiment of a scroll compressor according to the present disclosure,

[0048] FIG. 6 depicts an overview of a spiral compressor according to the present disclosure,

[0049] FIG. 7 depicts a cross-sectional view of an exemplary embodiment of a torque-transmission means of a compressor according to the present disclosure, equipped with a position sensor facing an electronic card,

[0050] FIG. 8A depicts an embodiment variant of the first integral portion of a torque-transmission means of a compressor according to the present disclosure,

[0051] FIG. 8B depicts another embodiment variant of the first integral portion of a torque-transmission means of a compressor according to the present disclosure,

[0052] FIG. 9A depicts a variant embodiment of the connection between the first and second integral portion of a torque-transmission means of a compressor according to the present disclosure,

[0053] FIG. 9B depicts another embodiment variant of the connection between the first and second integral portion of a torque-transmission means of a compressor according to the present disclosure,

[0054] FIG. 10 depicts another embodiment variant of the connection between the first and second integral portion of a torque-transmission means of a compressor according to the present disclosure,

[0055] FIG. 11 depicts another embodiment variant of the connection between the first and second integral portion of a torque-transmission means of a compressor according to the present disclosure,

[0056] FIG. 12 depicts another embodiment variant of the connection between the first and second integral portion of a torque-transmission means of a compressor according to the present disclosure,

[0057] FIG. 13 depicts another embodiment variant of the connection between the first and second integral portion of a torque-transmission means of a compressor according to the present disclosure,

[0058] FIG. 14 depicts another embodiment variant of the connection between the first and second integral portion of a torque-transmission means of a compressor according to the present disclosure, and

[0059] FIG. 15 depicts an embodiment variant of a position sensor of a torque-transmission means of a compressor according to the present disclosure.DETAILED DESCRIPTION

[0060] FIGS. 1-4 exemplify an example of the application of a torque-transmission means (100) according to the present disclosure for driving a member (300) performing an eccentric movement by an electric motor (200).

[0061] The example disclosed relates more specifically, but not limited to, an air compressor for supplying the braking system of a vehicle such as a truck or bus, and especially on electrified vehicles.

[0062] For such applications, different constraints apply to the design of the compressor: in addition to high reliability and robustness for a safety application, the application to a vehicle requires a reduced volume. For an electric vehicle, the constraint also relates to being lightweight and having high efficiency, so as not to compromise the range of the vehicle.

[0063] The present disclosure aims to respond to these constraints by proposing a system for coupling the motor (200) to the member (300), making it possible to reduce both the axial and radial volumes of the system, and also ensuring easy access to the components of the electric motor (200) on the one hand, and to the components of the component to be driven (300), in order to enable disassembly for maintenance, repair, testing, or even to offer a power range by keeping the member portion to be driven (300), for example, a compressor, unchanged and selecting for the motor portion (200) an active length of the rotor (220) and stator (210) that is suitable for the desired power.

[0064] The simplicity of the assembly also makes it possible to test partial components or sub-assemblies during the different assembly steps in production, for example, the electronic card (250) or the electric motor portion (200) alone, dissociated from the member (300) to be driven, or the member portion (300) to be driven, dissociated from the electric motor (200).

[0065] It also enables repair, maintenance or replacement of one of the defective portions (motor (200) or member (300) to be driven), or even the replacement by a more suitable portion.

[0066] These constraints also require perfect guidance of the torque-transmission means (100) and control of the axial and radial clearances of the different components, especially in a context of eccentric movement and imbalances that can cause accelerated fatigue of the torque-transmission means (100).

[0067] To meet these objectives, the torque-transmission means (100) consists of an assembly of two integral portions (110) and (150), shown separately in FIGS. 2-4. The first integral portion (110) supports the rotor (220) of the electric motor (200), and the second integral portion (150) drives the member (300).

[0068] “Integral” is understood as the fact that each of the portions (110, 150) is manufactured without assembly, from a single piece of material, for example, by machining a blank, by casting, and any other method avoiding an assembly of separate components.

[0069] An important aspect of the present disclosure relates to the coupling of these two portions (110, 150), which must be able to transmit a high torque between the motor (200) and the member (300), withstand the stresses resulting from eccentric movements, while allowing uncoupling to facilitate assembly and allow disassembly.

[0070] The electric machine has a first casing (510) in which the motor is housed, and a second casing (520) in which the member to be driven (300) is housed, the two being joined by an intermediate casing (530) to form a leak-tight housing (500) closed by a cover (540). In the subsequent description, “rear” refers to the closest side of the motor (200) and “front” to the closest side of the member to be driven (300).Embodiment Details of the First Integral Portion (110)

[0071] This first integral portion (110) is intended to support the rotor (220) of the motor (200). For this purpose, it consists of a piece having a cylindrical outer sleeve, with a plurality of tiers of different diameters:

[0072] a first cylindrical segment (111) supporting the rotor (220) of the electric motor (200) having an outer diameter Dr. The length of this first cylindrical segment (111) corresponds to the axial length of the rotor (220). The rotor (220) is mounted on this first segment (111) in a known manner.

[0073] a second cylindrical segment (112) supporting a rear bearing (240) having an outer diameter Db. This rear bearing (240) guides the torque-transmission means (100) with respect to the housing (500) of the device.

[0074] These two cylindrical segments (111, 112) are coaxial.

[0075] The first cylindrical segment (111) supporting the rotor (220) of the electric motor is preceded by a cylindrical segment (116), the outer diameter Ds of which is smaller than the outer diameter Dr. It enables a ring-shaped position sensor (260) to be positioned.

[0076] An intermediate segment (114) of diameter Dm, located between the first cylindrical segment (111) and the second cylindrical segment (112), is intended to receive an asymmetrical balance weight (124) that compensates the imbalance caused by the driven eccentric movement.

[0077] Optionally, and as shown in FIGS. 8A and 8B, the balance weight (124) is integrated into the bundle of laminations of the rotor (220) carried by the first integral portion (110), or even formed in a radial extension of the first integral portion (110).

[0078] Preferably, but not limited thereto, the cross-section of this intermediate segment (114) is larger than the cross section of the first cylindrical segment (111) and / or the cross section of the second cylindrical segment (112), so as to form shoulders against which the rotor (220) is respectively mounted and against which the rear bearing (240), mounted by sliding, is axially supported.

[0079] Optionally, an elastic axial preload means (241), for example, a spring washer, can be integrated between the rear bearing (240) and the shoulder of the intermediate cylindrical segment (114), especially to guarantee a longer service life for the guide elements.Embodiment Details of the Interlocking Connection

[0080] This first integral portion (110) has a hollow guide segment (115) for receiving a complementary male guide segment (155) of the second integral portion (150) and forming an interlocking connection having a high axial, tangential and radial stiffness.

[0081] In the example disclosed, it has a bottom (118) forming a front stop of the complementary male guide segment (155). This bottom (118) has a central bore (119) for a screw (180) to pass through, constituting a locking means (195) ensuring the connection and axial locking of the two integral portions (110, 150).

[0082] The first integral portion (110) also has an anti-rotation means consisting, in the example disclosed, of two flat surfaces (120, 121), complementary to two diametrically opposed flat surfaces (171), only one of which is visible in FIG. 2, provided on the complementary male guide segment (155).

[0083] In the example disclosed, these flat surfaces are symmetrical with respect to an axial plane; advantageously, they can be asymmetrical to allow only one assembly possibility. It is also possible to provide only one anti-rotation means on each portion, for example, a single flat surface.

[0084] Alternatively, and as shown in FIGS. 9A and 9B, the anti-rotation of the two integral portions (110, 150) can be achieved by means of a system of channels (148) or splines (149) located at the cavity (176) of the first integral portion and of the base (126) of the second integral portion.

[0085] Alternatively, and as shown in FIG. 10, the anti-rotation of the two integral portions (110, 150) can be achieved by way of a key (147) carried by the cylindrical segment (155), this key cooperating with a counterbore (146) located on the hollow guide segment (115) for locking the first and second integral portions.

[0086] Alternatively, and as illustrated in FIG. 11, the anti-rotation of the two portions (110, 150) can be achieved by means of an elastic pin (145) passing radially through the first and second integral portions at the cavity (126) and the base (176).

[0087] An important consideration is the long centering of the two integral portions (110, 150), necessary to avoid the need for additional guides. This long centering is ensured by the fact that the hollow guide segment (115) of the first integral portion (110) has an inner diameter corresponding to the outer diameter of the complementary male guide segment (155) of the second integral portion (150), preferably with an H7g6 type fit, referring to the fit table proposed by the specifications of standard ISO 286-1 dated Apr. 15, 2010.

[0088] Alternatively, the fit can be tighter, of the H7m6 or H7p6 type, with the two portions (110, 150) press-fitted together, while disassembly remains possible, for example, with heating.

[0089] To achieve the long centering of the two integral portions (110, 150), the length ratio between the length Lc and the diameter Dc is greater than 1.5, typically 2,

[0090] Lc corresponds to the length of tubular interaction between the hollow guide segment (115) of the first integral portion (110) and the complementary male guide segment (155) of the second integral portion (150),

[0091] Dc corresponds to the inner diameter of the hollow guide segment (115) of the first integral portion (110) and the outer diameter of the complementary male guide segment (155) of the second integral portion (150).

[0092] The hollow guide segment (115) of the first integral portion (110) opens into an asymmetrical inlet cavity (126) having a cross section larger than the cross section of the hollow guide segment (115), with two peripheral flat surfaces (120, 121) connected by two semi-tubular segments. The complementary male guide segment (155) of the second integral portion (150) has, at the rear of the complementary male guide segment (155) of the second integral portion (150), an asymmetrical base (176) with a cross section and axial length complementary to the cross section of this asymmetrical inlet cavity (126).Embodiment Details of the Second Integral Portion (150)

[0093] This second integral portion (150) is intended to drive the member (300) arranged in the housing (500). For this purpose, it consists of a piece having a cylindrical outer sleeve, with a plurality of tiers of different diameters:

[0094] a cylindrical segment (151) supporting a front bearing (245) having an outer diameter Da coaxial with the segments (111, 112) of the first integral portion (110). The front bearing (245) is press-fitted on this cylindrical segment (151) on the one hand, and on the through passage of the wall (531) of the intermediate casing (530) on the other.

[0095] a cylindrical drive segment (152), which is eccentric with respect to the longitudinal axis (102), having an outer diameter De,

[0096] a disc shoulder (163) forming an axial stop for positioning the front bearing (245).

[0097] The rear face of the disc shoulder (163) defines a cylindrical surface (153) cooperating with a gasket (532) for the passage of the wall (531) of the intermediate casing (530). This disc shoulder (163) extends rearwards, toward the motor, by the base (156) and the complementary male guide segment (155).

[0098] The complementary male guide segment (155) is at least partially solid. Solid is understood as the fact that the segment (155) is not open.

[0099] The front end (157) of the complementary male guide segment (155) has a hole having an axial thread (158) for locking by the above-mentioned screw (180), constituting a locking means (195) ensuring the connection and axial locking of the two portions (110, 150).

[0100] Alternatively, and as shown in FIG. 12, the axial locking of the two integral portions (110, 150) can be achieved by means of a threaded surface (144) located at the end of the cylindrical segment (155), this threaded surface passing axially through the intermediate cylindrical segment (114) of the first integral portion (110), this threaded surface (144) collaborating with a nut (143) for locking the first and second integral portions.

[0101] Alternatively, and as shown in FIG. 13, the axial locking of the two portions (110, 150) can be achieved by means of a smooth surface (142) located at the end of the cylindrical segment (155), this smooth surface passing axially through the intermediate cylindrical segment (114) of the first integral portion (110), this smooth surface being equipped with a groove suitable for receiving a stop ring (or circlip) (141) for locking the first and second integral portions.

[0102] Advantageously, especially to further reduce manufacturing costs, the axial locking and anti-rotation of the first and second integral portions can be achieved, as shown in FIG. 14, by a single, specific screw (180). The friction between the threads of the screw and the tapping of the threaded hole of the segment (155) of the second integral portion (150), on the one hand, and between the screw head and the front face (113) of the passage (119) of the first integral portion (110), on the other hand, enables torque transmission to serve the anti-rotation function.

[0103] The second integral portion (150) can be partially hollow, except a transverse partition (162) guaranteeing leak tightness, in conjunction with the gasket (532), in order to lighten the assembly.

[0104] In an advantageous embodiment, the second integral portion (150) has three hollow sections of decreasing diameter from front to back, with a wall having a thickness optimized to accommodate the lightening of the piece and mechanical resistance to torsion and axial deformation.

[0105] An intermediate segment (154) of diameter DM, located between the cylindrical segment (151) carrying the front bearing (245) and the eccentric cylindrical segment (152), is intended to receive an asymmetrical balance weight (174) that compensates the imbalance caused by the driven eccentric movement, this weight (174) cooperating with the weight (124) of the first integral portion (110). To this end, the balance weight (174) has a protrusion (177) projecting over an angular sector of outer radius RM and the center of which is located on the axis (102).

[0106] The anti-rotation means, especially in the example described, the flat surfaces (120, 121, 171) ensure the angular indexing of the balance weights (124, 174) according to an angular reference, which is in common with the angular reference of the driven eccentric member (300). To this end, the intermediate cylindrical segment (114) of the first integral portion (110) comprises a flat surface that cooperates with a corresponding flat surface (125) of the weight (124) for its angular indexing with respect to the flat surfaces (120, 121). To this end, the cylindrical segment (151) comprises an indexing pin (159) that cooperates with an oblong hole (175) in the weight (174) for its angular indexing with respect to the flat surfaces (171), only one of the flat surfaces being visible in FIG. 2.

[0107] The segment (152) is off-center and concentric to an eccentric axis (101), the eccentric axis (101) being transversely offset with respect to the longitudinal axis (102) by a distance dex and cooperates with the eccentrically moving piece of the driven member (300), for example, the member of a vane pump or a scroll-type pump.Embodiment Detail of the Housing (500)

[0108] The housing (500) is formed by the assembly of the first casing (510) in which the electric motor (200) is housed, an intermediate casing (530) and a second casing (520) in which the member (300) to be driven is housed.

[0109] The assembly forms a leak-tight housing (500) with a wall (531) fluidically isolating the electric motor (200) from the member (300) to be driven, using the gasket (532) and the transverse partition (162), the dynamic gasket (532) cooperating with the cylindrical segment (153) of the second, non-open, integral portion (150). Only two bearings (240, 245) guide the torque-transmission means (100) with respect to the housing (500),

[0110] the rear bearing (240), which is mounted in the cover (540) of the first casing (510) and on the segment (112) of the first integral portion (110), and

[0111] the front bearing (245), which is mounted in the wall (531) of the intermediate casing (530) and on the segment (151) of the second integral portion (150).

[0112] The interlocking connection formed by the tubular interaction area between the hollow guide segment (115) of the first integral portion (110) and the complementary male guide segment (155) of the second integral portion (150) is necessarily located between the rear bearing (240) and the front bearing (245).

[0113] By providing only two guide bearings despite the use of a torque-transmission means (100) in two portions (110, 150), a robust, economical and isostatic guidance is ensured, limiting the risk of high stresses.

[0114] The intermediate casing (530) has a series of fastening means, or several series of fastening means enabling the application contexts to be multiplied. This intermediate piece is close to the center of gravity of the device: it can also be equipped with a lifting grip, for handling the assembly of the compressor, for example, a lifting eyelet (538).

[0115] It must be noted that the first casing (510) receiving the electric motor (200) can consist of an assembly of several portions. For example, the jacket of the motor (515) can be assembled with the interface piece (516), receiving the electronic card (250), to form the first casing. This method is especially advantageous for reducing manufacturing costs when multiple lengths of electric motor (200) are envisaged to meet different specifications, while retaining the majority of the components of the system.Embodiment Details of the Electronic Card (250)

[0116] The electric motor (200) consists, in a known manner, of a rotor (220) and a wound stator (210), controlled by an electronic card (250) arranged transversely between the wall (531) and the rotor (220), protected in a leak-tight manner behind the gasket (532). The electronic card (250) is pierced by a cutout (251) the diameter of which is greater than those of the segments (111, 116, 155, 176) that pass therethrough during assembly or disassembly.

[0117] To ensure the cooling of the components of the electronic card (250), it is advantageous to ensure thermal coupling with the first casing (510), especially when the casing (510) is connected to a circulation circuit of a cooling fluid.

[0118] The sensor (260) mounted on the segment (116) of the first integral portion (110) passing through the electronic card (250) is arranged axially to the electronic card (250), so as to enable an electromagnetic or optionally optical interaction with a probe arranged on the card (250). Alternatively to a permanent magnet solution, the sensor (260) can be a magnetless inductive or variable reluctance sensor achieved by the cooperation of a ferromagnetic target (261), mounted on the additional cylindrical segment (116) of the first integral portion (110), with a probe of the electronic card, as shown in FIG. 15.

Examples

Embodiment Construction

[0060]FIGS. 1-4 exemplify an example of the application of a torque-transmission means (100) according to the present disclosure for driving a member (300) performing an eccentric movement by an electric motor (200).

[0061]The example disclosed relates more specifically, but not limited to, an air compressor for supplying the braking system of a vehicle such as a truck or bus, and especially on electrified vehicles.

[0062]For such applications, different constraints apply to the design of the compressor: in addition to high reliability and robustness for a safety application, the application to a vehicle requires a reduced volume. For an electric vehicle, the constraint also relates to being lightweight and having high efficiency, so as not to compromise the range of the vehicle.

[0063]The present disclosure aims to respond to these constraints by proposing a system for coupling the motor (200) to the member (300), making it possible to reduce both the axial and radial volumes of the s...

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application is a national phase entry under 35 U.S.C. § 371 of International Patent Application PCT / EP2024 / 060784, filed Apr. 19, 2024, designating the United States of America and published as International Patent Publication WO 2024 / 223443 A1 on Oct. 31, 2024, which claims the benefit under Article 8 of the Patent Cooperation Treaty of European Patent Office Application Serial No. 23169599.0, filed Apr. 24, 2023, and of French Patent Application Serial No. FR2304856, filed May 16, 2023.TECHNICAL FIELD

[0002] The present disclosure relates to the field of electrical devices formed by an eccentric member driven by an electrical machine.BACKGROUND

[0003] Driving an eccentric member generates high mechanical stresses due to the asymmetries of the rotary masses, especially on the coupling of the motor axle and the driven member.

[0004] A non-limiting example of such devices is a scroll-type compressor consisting of two spirals, one fixed, the other in orbital movement, which creates the compression, the suction chamber is located around the two spirals, and the discharge is located in the center, where the gas escapes through a hole.

[0005] Vane compressors are another example of such electrical devices with eccentric movement. The principle consists of a cylindrical stator (housing) with a radial inlet and outlet, in which an eccentrically-mounted circular rotor rotates. The rotor or stator is equipped with slots in which the vanes can slide radially. When the rotor rotates, the vanes ensure the closure of the gap between the stator wall and the rotor wall. A gap then forms between the stator wall, the two vanes and the rotor, which narrows as the rotor rotates toward the compressed air outlet.

[0006] Motors associated with hypocycloid gearboxes consist of another example of devices with an eccentric member, as well as epicycloidal gear trains.

[0007] In the state of the art, devices are known implementing a single drive shaft directly controlling the orbital movement of the eccentric member.

[0008] U.S. Pat. No. 5,040,958 describes a scroll compressor comprising a stationary scroll element comprising a stationary end plate and a stationary spiral wrap extending from the stationary end plate; an orbiting scroll element comprising an orbiting end plate and an orbiting spiral wrap extending from the orbiting end plate that orbits about the axis of the stationary scroll member and has an orbital bearing, the wraps of the stationary scroll member and the orbiting scroll member engaging with each other to form a fluid compressing chamber;

[0009] An anti-rotating device for preventing the orbiting scroll member from rotating on its own axis and permits the orbiting scroll member to orbit around the axis of the stationary scroll member. A main shaft rotatable on its own axis and having a pivot pin incorporating an axis spaced from the axis of the main shaft. An eccentric drive shaft having an axis spaced from the axis of the main shaft and orbital about the axis of the main shaft, the eccentric drive shaft being able to be engaged rotationally with the orbiting bearing so as to enable the eccentric drive shaft to drive the orbiting scroll member about the axis of the stationary scroll member, the eccentric drive shaft comprising a pivot bearing having an axis spaced from the axis of the eccentric drive shaft and being able to be rotationally engaged with the pivot pin so that the eccentric drive shaft rotates about the axis of the pivot pin, a distance between the axis of the eccentric drive shaft and the axis of the main shaft is adapted to be changed, and the main shaft drives the eccentric drive shaft to orbit about the axis of the main shaft. The rotational moment generated by the centrifugal force of the balance weight draws the eccentric drive shaft toward the main shaft; limiting means for limiting a range of orbital movement of the eccentric drive shaft about the axis of the pivot pin, a distance between the limiting means and the axis of the main shaft is larger in a direction of a line extending between the axis of the main shaft and the axis of the eccentric drive shaft than a distance between the axis of the main shaft and the axis of the pivot pin.

[0010] European Patent Application Publication No. 2,636,903 A2 describes a rotary compressor comprising a housing, a cylinder, a rotating shaft, a roller and an eccentric cam. The cylinder can be installed inside the housing and configured to provide a space for compressing the gas. The rotating shaft can be arranged to pass through the cylinder. The roller can be configured to compress gas by rotating along an inner circumferential surface of the cylinder. The eccentric cam can be integrally formed with the rotary shaft and arranged inside the roller. The eccentric cam can be arranged at an eccentric position in a shaft direction on an axial line of the rotary shaft.

[0011] The solutions of the prior art have several drawbacks. Solutions providing for a single, integral axle with an eccentric end involve complex operations for assembling and disassembling the axle. These solutions are not easy to repair.

[0012] They also involve long, costly and complex machining operations: machining the raw bar will generate a large quantity of swarf, especially through the considerable span length to be performed (machining, number of passes, hardening, grinding).

[0013] Assembly is complicated: the single axle receives a bearing at each end and a bundle of rotor laminations in the center, it is then integrated into the system frame through the stator pre-assembled in the main housing, the rear bearing carrying the axle engaging in the main housing. The front bearing is supported by a secondary housing (compressor compartment) attached to the main housing. This type of assembly is highly restrictive in terms of the size and dimensions of the bearings (which must be able to pass through the stator, and therefore be smaller than its internal diameter) on the one hand, and the implementation of balance means and weights on the other.

[0014] In addition, single-axle solutions pose a problem for the insertion of a printed drive circuit board of the motor, unless a slot is provided to slide the printed circuit board about the axle, which reduces the surface available on the PCB. These prior art solutions mean that the control electronics must be located at the rear of the system, leading to a larger volume, greater distance between the motor and the electronics (and therefore greater complexity and cost for the electrical connections to the stator and the position / speed sensor function), and the need to provide a specific liquid cooling circuit for the electronics at the rear.BRIEF SUMMARY

[0015] In order to solve the disadvantages of the background art, the present disclosure relates in its most general sense to a device comprising a member performing an eccentric movement coupled to an electric motor, wherein the eccentric member is driven by the electric motor via a torque-transmission means consisting of two tubular integral portions coupled by an interlocking connection.

[0016] The first integral portion having:

[0017] a first cylindrical segment supporting the rotor of the electric motor having an outer diameter Dr,

[0018] a second cylindrical segment supporting a rear bearing having an outer diameter Db, and

[0019] the segments being coaxial.

[0020] The second integral portion having:

[0021] a cylindrical segment supporting a front bearing having an outer diameter Da coaxial with the segments of the first portion, and

[0022] a cylindrical drive segment, which is eccentric with respect to the longitudinal axis, having an outer diameter De.

[0023] The two integral portions being coupled by an interlocking connection consisting of:

[0024] a male guide segment of outer diameter Dc and of length LINTERLOCKING extending one of the integral portions (110, 150), engaged in a hollow female guide segment (115) of depth Lc provided in the other of the portions, where Lc is greater than or equal to 1.5 times Dc, and

[0025] the two integral portions further comprising at least one angular and axial locking means.

[0026] According to variants:

[0027] the first integral portion further has an additional cylindrical segment supporting a sensor having an outer diameter Ds coaxial with the longitudinal axis,

[0028] the first integral portion further has an additional cylindrical segment supporting a rear balance weight having an outer diameter Dm coaxial with the longitudinal axis,

[0029] the first integral portion further has an annular shoulder adjacent to the cylindrical segment supporting the rotor of the electric motor, for the axial positioning of the rotor,

[0030] the second portion further has an additional cylindrical segment supporting a front balance weight having an outer diameter DM, the additional segment being coaxial with the longitudinal axis when the two portions are coupled,

[0031] the second portion further has an additional cylindrical segment matching the passage of the wall separating the motor from the driven member having an outer diameter Da,

[0032] the motor comprises a printed circuit board arranged transversely between the rotor (220) and the second bearing, the printed circuit board having a passage through which the torque-transmission means passes,

[0033] the one or more segments passing through the passage of the printed circuit board have the smallest diameters,

[0034] the sensor-carrying segment is the segment closest to the printed circuit board,

[0035] at least one of the first and second portion is hollow, except the front walls of the male and female guide segments,

[0036] the angular locking means consists of cooperating torque-transmission flat surfaces,

[0037] the axial locking means consists of an axial screw connecting the male guide segment and the female guide segment, the axial end of the male guide segment having an axial thread and the bottom of the female guide segment having a bore for the passage of the screw ensuring the axial end of the male guide segment is blocked against the bottom of the female guide segment,

[0038] the device comprises a first casing cooled by fluid circulation, the first casing comprising the electric motor, and a second casing cooled by fluid circulation, comprising the eccentrically driven member, and wherein the fluid circulation circuits of the two casings open onto adjacent faces in alignment when the casings are joined together,

[0039] comprises an intermediate casing comprising at least two fluid connections opening on one side at the fluid connections of the first casing and on the other side at the fluid connections of the second casing,

[0040] the intermediate casing comprises at least two fastening means, and

[0041] the intermediate casing comprises at least one lifting eyelet.BRIEF DESCRIPTION OF THE DRAWINGS

[0042] The present disclosure will be better understood from reading the following description, which relates to a non-limiting exemplary embodiment illustrated by the accompanying drawings, in which:

[0043] FIG. 1 depicts an overview of the motorization, in a front three-quarter perspective cross-sectional view of an exemplary embodiment of a scroll compressor according to the present disclosure,

[0044] FIG. 2 depicts an exploded view of an exemplary embodiment of a torque-transmission means, equipped with two integral portions, for a compressor according to the present disclosure,

[0045] FIG. 3 depicts a cross-sectional view of the first integral portion of a torque-transmission means according to the present disclosure,

[0046] FIG. 4 depicts a cross-sectional view of the second integral portion of a torque-transmission means according to the present disclosure, in a perspective view of an exemplary embodiment of a compressor according to the present disclosure,

[0047] FIG. 5 depicts an overview of the motorization, in an exploded front three-quarter perspective view of an exemplary embodiment of a scroll compressor according to the present disclosure,

[0048] FIG. 6 depicts an overview of a spiral compressor according to the present disclosure,

[0049] FIG. 7 depicts a cross-sectional view of an exemplary embodiment of a torque-transmission means of a compressor according to the present disclosure, equipped with a position sensor facing an electronic card,

[0050] FIG. 8A depicts an embodiment variant of the first integral portion of a torque-transmission means of a compressor according to the present disclosure,

[0051] FIG. 8B depicts another embodiment variant of the first integral portion of a torque-transmission means of a compressor according to the present disclosure,

[0052] FIG. 9A depicts a variant embodiment of the connection between the first and second integral portion of a torque-transmission means of a compressor according to the present disclosure,

[0053] FIG. 9B depicts another embodiment variant of the connection between the first and second integral portion of a torque-transmission means of a compressor according to the present disclosure,

[0054] FIG. 10 depicts another embodiment variant of the connection between the first and second integral portion of a torque-transmission means of a compressor according to the present disclosure,

[0055] FIG. 11 depicts another embodiment variant of the connection between the first and second integral portion of a torque-transmission means of a compressor according to the present disclosure,

[0056] FIG. 12 depicts another embodiment variant of the connection between the first and second integral portion of a torque-transmission means of a compressor according to the present disclosure,

[0057] FIG. 13 depicts another embodiment variant of the connection between the first and second integral portion of a torque-transmission means of a compressor according to the present disclosure,

[0058] FIG. 14 depicts another embodiment variant of the connection between the first and second integral portion of a torque-transmission means of a compressor according to the present disclosure, and

[0059] FIG. 15 depicts an embodiment variant of a position sensor of a torque-transmission means of a compressor according to the present disclosure.DETAILED DESCRIPTION

[0060] FIGS. 1-4 exemplify an example of the application of a torque-transmission means (100) according to the present disclosure for driving a member (300) performing an eccentric movement by an electric motor (200).

[0061] The example disclosed relates more specifically, but not limited to, an air compressor for supplying the braking system of a vehicle such as a truck or bus, and especially on electrified vehicles.

[0062] For such applications, different constraints apply to the design of the compressor: in addition to high reliability and robustness for a safety application, the application to a vehicle requires a reduced volume. For an electric vehicle, the constraint also relates to being lightweight and having high efficiency, so as not to compromise the range of the vehicle.

[0063] The present disclosure aims to respond to these constraints by proposing a system for coupling the motor (200) to the member (300), making it possible to reduce both the axial and radial volumes of the system, and also ensuring easy access to the components of the electric motor (200) on the one hand, and to the components of the component to be driven (300), in order to enable disassembly for maintenance, repair, testing, or even to offer a power range by keeping the member portion to be driven (300), for example, a compressor, unchanged and selecting for the motor portion (200) an active length of the rotor (220) and stator (210) that is suitable for the desired power.

[0064] The simplicity of the assembly also makes it possible to test partial components or sub-assemblies during the different assembly steps in production, for example, the electronic card (250) or the electric motor portion (200) alone, dissociated from the member (300) to be driven, or the member portion (300) to be driven, dissociated from the electric motor (200).

[0065] It also enables repair, maintenance or replacement of one of the defective portions (motor (200) or member (300) to be driven), or even the replacement by a more suitable portion.

[0066] These constraints also require perfect guidance of the torque-transmission means (100) and control of the axial and radial clearances of the different components, especially in a context of eccentric movement and imbalances that can cause accelerated fatigue of the torque-transmission means (100).

[0067] To meet these objectives, the torque-transmission means (100) consists of an assembly of two integral portions (110) and (150), shown separately in FIGS. 2-4. The first integral portion (110) supports the rotor (220) of the electric motor (200), and the second integral portion (150) drives the member (300).

[0068] “Integral” is understood as the fact that each of the portions (110, 150) is manufactured without assembly, from a single piece of material, for example, by machining a blank, by casting, and any other method avoiding an assembly of separate components.

[0069] An important aspect of the present disclosure relates to the coupling of these two portions (110, 150), which must be able to transmit a high torque between the motor (200) and the member (300), withstand the stresses resulting from eccentric movements, while allowing uncoupling to facilitate assembly and allow disassembly.

[0070] The electric machine has a first casing (510) in which the motor is housed, and a second casing (520) in which the member to be driven (300) is housed, the two being joined by an intermediate casing (530) to form a leak-tight housing (500) closed by a cover (540). In the subsequent description, “rear” refers to the closest side of the motor (200) and “front” to the closest side of the member to be driven (300).Embodiment Details of the First Integral Portion (110)

[0071] This first integral portion (110) is intended to support the rotor (220) of the motor (200). For this purpose, it consists of a piece having a cylindrical outer sleeve, with a plurality of tiers of different diameters:

[0072] a first cylindrical segment (111) supporting the rotor (220) of the electric motor (200) having an outer diameter Dr. The length of this first cylindrical segment (111) corresponds to the axial length of the rotor (220). The rotor (220) is mounted on this first segment (111) in a known manner.

[0073] a second cylindrical segment (112) supporting a rear bearing (240) having an outer diameter Db. This rear bearing (240) guides the torque-transmission means (100) with respect to the housing (500) of the device.

[0074] These two cylindrical segments (111, 112) are coaxial.

[0075] The first cylindrical segment (111) supporting the rotor (220) of the electric motor is preceded by a cylindrical segment (116), the outer diameter Ds of which is smaller than the outer diameter Dr. It enables a ring-shaped position sensor (260) to be positioned.

[0076] An intermediate segment (114) of diameter Dm, located between the first cylindrical segment (111) and the second cylindrical segment (112), is intended to receive an asymmetrical balance weight (124) that compensates the imbalance caused by the driven eccentric movement.

[0077] Optionally, and as shown in FIGS. 8A and 8B, the balance weight (124) is integrated into the bundle of laminations of the rotor (220) carried by the first integral portion (110), or even formed in a radial extension of the first integral portion (110).

[0078] Preferably, but not limited thereto, the cross-section of this intermediate segment (114) is larger than the cross section of the first cylindrical segment (111) and / or the cross section of the second cylindrical segment (112), so as to form shoulders against which the rotor (220) is respectively mounted and against which the rear bearing (240), mounted by sliding, is axially supported.

[0079] Optionally, an elastic axial preload means (241), for example, a spring washer, can be integrated between the rear bearing (240) and the shoulder of the intermediate cylindrical segment (114), especially to guarantee a longer service life for the guide elements.Embodiment Details of the Interlocking Connection

[0080] This first integral portion (110) has a hollow guide segment (115) for receiving a complementary male guide segment (155) of the second integral portion (150) and forming an interlocking connection having a high axial, tangential and radial stiffness.

[0081] In the example disclosed, it has a bottom (118) forming a front stop of the complementary male guide segment (155). This bottom (118) has a central bore (119) for a screw (180) to pass through, constituting a locking means (195) ensuring the connection and axial locking of the two integral portions (110, 150).

[0082] The first integral portion (110) also has an anti-rotation means consisting, in the example disclosed, of two flat surfaces (120, 121), complementary to two diametrically opposed flat surfaces (171), only one of which is visible in FIG. 2, provided on the complementary male guide segment (155).

[0083] In the example disclosed, these flat surfaces are symmetrical with respect to an axial plane; advantageously, they can be asymmetrical to allow only one assembly possibility. It is also possible to provide only one anti-rotation means on each portion, for example, a single flat surface.

[0084] Alternatively, and as shown in FIGS. 9A and 9B, the anti-rotation of the two integral portions (110, 150) can be achieved by means of a system of channels (148) or splines (149) located at the cavity (176) of the first integral portion and of the base (126) of the second integral portion.

[0085] Alternatively, and as shown in FIG. 10, the anti-rotation of the two integral portions (110, 150) can be achieved by way of a key (147) carried by the cylindrical segment (155), this key cooperating with a counterbore (146) located on the hollow guide segment (115) for locking the first and second integral portions.

[0086] Alternatively, and as illustrated in FIG. 11, the anti-rotation of the two portions (110, 150) can be achieved by means of an elastic pin (145) passing radially through the first and second integral portions at the cavity (126) and the base (176).

[0087] An important consideration is the long centering of the two integral portions (110, 150), necessary to avoid the need for additional guides. This long centering is ensured by the fact that the hollow guide segment (115) of the first integral portion (110) has an inner diameter corresponding to the outer diameter of the complementary male guide segment (155) of the second integral portion (150), preferably with an H7g6 type fit, referring to the fit table proposed by the specifications of standard ISO 286-1 dated Apr. 15, 2010.

[0088] Alternatively, the fit can be tighter, of the H7m6 or H7p6 type, with the two portions (110, 150) press-fitted together, while disassembly remains possible, for example, with heating.

[0089] To achieve the long centering of the two integral portions (110, 150), the length ratio between the length Lc and the diameter Dc is greater than 1.5, typically 2,

[0090] Lc corresponds to the length of tubular interaction between the hollow guide segment (115) of the first integral portion (110) and the complementary male guide segment (155) of the second integral portion (150),

[0091] Dc corresponds to the inner diameter of the hollow guide segment (115) of the first integral portion (110) and the outer diameter of the complementary male guide segment (155) of the second integral portion (150).

[0092] The hollow guide segment (115) of the first integral portion (110) opens into an asymmetrical inlet cavity (126) having a cross section larger than the cross section of the hollow guide segment (115), with two peripheral flat surfaces (120, 121) connected by two semi-tubular segments. The complementary male guide segment (155) of the second integral portion (150) has, at the rear of the complementary male guide segment (155) of the second integral portion (150), an asymmetrical base (176) with a cross section and axial length complementary to the cross section of this asymmetrical inlet cavity (126).Embodiment Details of the Second Integral Portion (150)

[0093] This second integral portion (150) is intended to drive the member (300) arranged in the housing (500). For this purpose, it consists of a piece having a cylindrical outer sleeve, with a plurality of tiers of different diameters:

[0094] a cylindrical segment (151) supporting a front bearing (245) having an outer diameter Da coaxial with the segments (111, 112) of the first integral portion (110). The front bearing (245) is press-fitted on this cylindrical segment (151) on the one hand, and on the through passage of the wall (531) of the intermediate casing (530) on the other.

[0095] a cylindrical drive segment (152), which is eccentric with respect to the longitudinal axis (102), having an outer diameter De,

[0096] a disc shoulder (163) forming an axial stop for positioning the front bearing (245).

[0097] The rear face of the disc shoulder (163) defines a cylindrical surface (153) cooperating with a gasket (532) for the passage of the wall (531) of the intermediate casing (530). This disc shoulder (163) extends rearwards, toward the motor, by the base (156) and the complementary male guide segment (155).

[0098] The complementary male guide segment (155) is at least partially solid. Solid is understood as the fact that the segment (155) is not open.

[0099] The front end (157) of the complementary male guide segment (155) has a hole having an axial thread (158) for locking by the above-mentioned screw (180), constituting a locking means (195) ensuring the connection and axial locking of the two portions (110, 150).

[0100] Alternatively, and as shown in FIG. 12, the axial locking of the two integral portions (110, 150) can be achieved by means of a threaded surface (144) located at the end of the cylindrical segment (155), this threaded surface passing axially through the intermediate cylindrical segment (114) of the first integral portion (110), this threaded surface (144) collaborating with a nut (143) for locking the first and second integral portions.

[0101] Alternatively, and as shown in FIG. 13, the axial locking of the two portions (110, 150) can be achieved by means of a smooth surface (142) located at the end of the cylindrical segment (155), this smooth surface passing axially through the intermediate cylindrical segment (114) of the first integral portion (110), this smooth surface being equipped with a groove suitable for receiving a stop ring (or circlip) (141) for locking the first and second integral portions.

[0102] Advantageously, especially to further reduce manufacturing costs, the axial locking and anti-rotation of the first and second integral portions can be achieved, as shown in FIG. 14, by a single, specific screw (180). The friction between the threads of the screw and the tapping of the threaded hole of the segment (155) of the second integral portion (150), on the one hand, and between the screw head and the front face (113) of the passage (119) of the first integral portion (110), on the other hand, enables torque transmission to serve the anti-rotation function.

[0103] The second integral portion (150) can be partially hollow, except a transverse partition (162) guaranteeing leak tightness, in conjunction with the gasket (532), in order to lighten the assembly.

[0104] In an advantageous embodiment, the second integral portion (150) has three hollow sections of decreasing diameter from front to back, with a wall having a thickness optimized to accommodate the lightening of the piece and mechanical resistance to torsion and axial deformation.

[0105] An intermediate segment (154) of diameter DM, located between the cylindrical segment (151) carrying the front bearing (245) and the eccentric cylindrical segment (152), is intended to receive an asymmetrical balance weight (174) that compensates the imbalance caused by the driven eccentric movement, this weight (174) cooperating with the weight (124) of the first integral portion (110). To this end, the balance weight (174) has a protrusion (177) projecting over an angular sector of outer radius RM and the center of which is located on the axis (102).

[0106] The anti-rotation means, especially in the example described, the flat surfaces (120, 121, 171) ensure the angular indexing of the balance weights (124, 174) according to an angular reference, which is in common with the angular reference of the driven eccentric member (300). To this end, the intermediate cylindrical segment (114) of the first integral portion (110) comprises a flat surface that cooperates with a corresponding flat surface (125) of the weight (124) for its angular indexing with respect to the flat surfaces (120, 121). To this end, the cylindrical segment (151) comprises an indexing pin (159) that cooperates with an oblong hole (175) in the weight (174) for its angular indexing with respect to the flat surfaces (171), only one of the flat surfaces being visible in FIG. 2.

[0107] The segment (152) is off-center and concentric to an eccentric axis (101), the eccentric axis (101) being transversely offset with respect to the longitudinal axis (102) by a distance dex and cooperates with the eccentrically moving piece of the driven member (300), for example, the member of a vane pump or a scroll-type pump.Embodiment Detail of the Housing (500)

[0108] The housing (500) is formed by the assembly of the first casing (510) in which the electric motor (200) is housed, an intermediate casing (530) and a second casing (520) in which the member (300) to be driven is housed.

[0109] The assembly forms a leak-tight housing (500) with a wall (531) fluidically isolating the electric motor (200) from the member (300) to be driven, using the gasket (532) and the transverse partition (162), the dynamic gasket (532) cooperating with the cylindrical segment (153) of the second, non-open, integral portion (150). Only two bearings (240, 245) guide the torque-transmission means (100) with respect to the housing (500),

[0110] the rear bearing (240), which is mounted in the cover (540) of the first casing (510) and on the segment (112) of the first integral portion (110), and

[0111] the front bearing (245), which is mounted in the wall (531) of the intermediate casing (530) and on the segment (151) of the second integral portion (150).

[0112] The interlocking connection formed by the tubular interaction area between the hollow guide segment (115) of the first integral portion (110) and the complementary male guide segment (155) of the second integral portion (150) is necessarily located between the rear bearing (240) and the front bearing (245).

[0113] By providing only two guide bearings despite the use of a torque-transmission means (100) in two portions (110, 150), a robust, economical and isostatic guidance is ensured, limiting the risk of high stresses.

[0114] The intermediate casing (530) has a series of fastening means, or several series of fastening means enabling the application contexts to be multiplied. This intermediate piece is close to the center of gravity of the device: it can also be equipped with a lifting grip, for handling the assembly of the compressor, for example, a lifting eyelet (538).

[0115] It must be noted that the first casing (510) receiving the electric motor (200) can consist of an assembly of several portions. For example, the jacket of the motor (515) can be assembled with the interface piece (516), receiving the electronic card (250), to form the first casing. This method is especially advantageous for reducing manufacturing costs when multiple lengths of electric motor (200) are envisaged to meet different specifications, while retaining the majority of the components of the system.Embodiment Details of the Electronic Card (250)

[0116] The electric motor (200) consists, in a known manner, of a rotor (220) and a wound stator (210), controlled by an electronic card (250) arranged transversely between the wall (531) and the rotor (220), protected in a leak-tight manner behind the gasket (532). The electronic card (250) is pierced by a cutout (251) the diameter of which is greater than those of the segments (111, 116, 155, 176) that pass therethrough during assembly or disassembly.

[0117] To ensure the cooling of the components of the electronic card (250), it is advantageous to ensure thermal coupling with the first casing (510), especially when the casing (510) is connected to a circulation circuit of a cooling fluid.

[0118] The sensor (260) mounted on the segment (116) of the first integral portion (110) passing through the electronic card (250) is arranged axially to the electronic card (250), so as to enable an electromagnetic or optionally optical interaction with a probe arranged on the card (250). Alternatively to a permanent magnet solution, the sensor (260) can be a magnetless inductive or variable reluctance sensor achieved by the cooperation of a ferromagnetic target (261), mounted on the additional cylindrical segment (116) of the first integral portion (110), with a probe of the electronic card, as shown in FIG. 15.

Examples

Embodiment Construction

[0060]FIGS. 1-4 exemplify an example of the application of a torque-transmission means (100) according to the present disclosure for driving a member (300) performing an eccentric movement by an electric motor (200).

[0061]The example disclosed relates more specifically, but not limited to, an air compressor for supplying the braking system of a vehicle such as a truck or bus, and especially on electrified vehicles.

[0062]For such applications, different constraints apply to the design of the compressor: in addition to high reliability and robustness for a safety application, the application to a vehicle requires a reduced volume. For an electric vehicle, the constraint also relates to being lightweight and having high efficiency, so as not to compromise the range of the vehicle.

[0063]The present disclosure aims to respond to these constraints by proposing a system for coupling the motor (200) to the member (300), making it possible to reduce both the axial and radial volumes of the s...

Claims

1. A motorized device comprising a torque-transmission means, an electric motor and a member performing an eccentric movement coupled to the electric motor, wherein the eccentric member is driven by the electric motor by the torque-transmission means, the torque-transmission means including two tubular integral portions coupled by an interlocking connection,the first integral portion having:a first cylindrical segment supporting a rotor of the electric motor having an outer diameter Dr,a second cylindrical segment supporting a rear bearing having an outer diameter Db, the segments being coaxial with a first longitudinal axis,the second integral portion having:a cylindrical segment supporting a front bearing having an outer diameter Da coaxial with the first longitudinal axis,a cylindrical drive segment, eccentric with respect to the longitudinal axis, having an outer diameter De,the two integral portions being coupled by an interlocking connection including:a male guide segment of outer diameter Dcet and length Lc extending one of the integral portions, engaged in a hollow female guide segment of depth Lc provided in the other one of the portions, where Lc is greater than or equal to 1.5 times Dc,the two integral portions further comprising at least one angular and axial locking means.

2. The motorized device of claim 1, wherein the first integral portion has an additional cylindrical segment supporting a sensor having an outer diameter Ds coaxial with the longitudinal axis.

3. The motorized device of claim 1, wherein the first integral portion has an additional cylindrical segment supporting a rear balance weight having an outer diameter Dm coaxial with the longitudinal axis.

4. The motorized device of claim 1, wherein the first integral portion has an annular shoulder adjacent to the cylindrical segment supporting the rotor of the electric motor, for the axial positioning of the rotor.

5. The motorized device of claim 1, wherein the second portion has an additional cylindrical segment supporting a front balance weight having an outer diameter DM, the additional segment being coaxial with the eccentric axis when the two portions are coupled, the balance weight having a protrusion projecting over an angular sector of outer radius RM and with the center located on the longitudinal axis.

6. The motorized device of claim 1, wherein the second portion has an additional cylindrical segment corresponding to a passage of a wall separating the motor from the driven member, and wherein a gasket cooperates with the cylindrical segment and the wall.

7. The motorized device of claim 1, wherein the motor comprises a printed circuit board arranged transversely between the rotor and the front bearing, the printed circuit board having a passage through which the torque-transmission means passes.

8. The motorized device of claim 7, wherein the one or more segments passing through the passage of the printed circuit board have the smallest diameters.

9. The motorized device of claim 8, wherein the first integral portion has an additional cylindrical segment supporting a sensor having an outer diameter Ds coaxial with the longitudinal axis, and the segment carrying the sensor is the segment closest to the printed circuit board.

10. The motorized device of claim 1, wherein at least one of the first and second integral portions is hollow, except for a transverse partition, to provide leak tightness.

11. The motorized device of claim 1, wherein the angular locking means comprises cooperating torque-transmission flat surfaces.

12. The motorized device claim 1, wherein the axial locking means comprises an axial screw connecting the male guide segment and the female guide segment, the axial end of the male guide segment having an axial thread and the bottom of the female guide segment having a bore for the passage of the screw ensuring the axial end of the male guide segment is blocked against the bottom of the female guide segment.

13. The motorized device of claim 12, further comprising an intermediate casing having at least two fastening means.

14. The motorized device of claim 1, wherein the intermediate casing comprises at least one lifting eyelet.

15. The motorized device of claim 2, wherein the first integral portion has an additional cylindrical segment supporting a rear balance weight having an outer diameter Dmcoaxial with the longitudinal axis.

16. The motorized device of claim 2, wherein the first integral portion has an annular shoulder adjacent to the cylindrical segment supporting the rotor of the electric motor, for the axial positioning of the rotor.

17. The motorized device of claim 2, wherein the second portion has an additional cylindrical segment supporting a front balance weight having an outer diameter DM, the additional segment being coaxial with the eccentric axis when the two portions are coupled, the balance weight having a protrusion projecting over an angular sector of outer radius RM and with the center located on the longitudinal axis.

Images