EP4010596B1

EP4010596B1 - Rotor and pump comprising such rotor

Info

Publication number: EP4010596B1
Application number: EP20750667.6A
Authority: EP
Inventors: Stefania PASQUALI; Simona BELA; Vito RUFRANO; Leonardo Cadeddu
Original assignee: VHIT SpA
Current assignee: VHIT SpA
Priority date: 2019-08-09
Filing date: 2020-08-05
Publication date: 2023-07-26
Anticipated expiration: 2040-08-05
Also published as: IT201900014601A1; WO2021028291A1; CN114514378A; EP4010596A1

Description

Technical Field

The present invention relates to a rotor and a pump comprising such rotor. More particularly, the rotor is of the vane type comprising a vane carrier made of a thermoplastic material and a transmission coupling made of a metal material, connected to the vane carrier and adapted to receive a drive torque from a drive member.
The pump which is the subject matter of the present invention finds particular application in the automotive industry, in particular as a vacuum pump capable of providing an air vacuum to brake assist devices or as a combined pump, used both as a vacuum pump and to supply fuel to an internal combustion engine.

Background Art

Among the known types of pumps, particularly vacuum pumps, there are vane pumps comprising a rotor capable of driving at least one vane and connected to a drive member, such as an engine camshaft. The rotor comprises a vane carrier, in which at least one vane is mounted in a movable manner, and a transmission coupling connected to the vane carrier and arranged to receive a drive torque provided by the camshaft and to transmit said torque to the vane carrier so as to create an air vacuum. More particularly, the transmission of the drive torque from the transmission coupling to the vane carrier takes place by means of thrust surfaces of the transmission coupling that are parallel to a longitudinal axis of rotation of the rotor and exert a thrust against corresponding abutment surfaces of the vane carrier, said abutment surfaces, too, being substantially parallel to the axis of rotation of the rotor.
Among the pumps like those described above, there are pumps in which, for the purpose of reducing the weight and cost thereof, the vane carrier is made of a thermoplastic material, whereas the transmission coupling, having to be capable of receiving the drive torque provided by the camshaft, is made of steel. In such cases, problems of reliability may arise, as the contact between the transmission coupling and the vane carrier can lead to wear of the vane carrier: this is due to the fact that the contact between the transmission coupling and the vane carrier always consists of a combination of compression and rubbing, or sliding friction, in a direction perpendicular to the axis of rotation of the rotor. Here below, for ease of discussion, this combination of compression and rubbing will simply be referred to as contact wear.
In order to limit the problem of the wear of the vane carrier, document WO 02/097274 A2 , in the name of the Applicant, describes a rotor comprising a support element having two wings arranged between thrust surfaces of the transmission coupling and corresponding abutment surfaces of the vane carrier as described above, respectively.
The Applicant has noticed that the known rotor described above does not adequately solve the problem of vane carrier wear, particularly in the case of the most recent applications, where the camshaft, due to the use of an additional cam that drives a high-pressure fuel injection pump, or other auxiliary parts of the vehicle, can generate, under certain conditions, an important and impulsive reversal of the drive torque, with consequent radial and axial pulsation of the transmission coupling. As a result of this, there is generated further transverse and/or axial wear of the vane carrier as well as wear on surfaces of the vane carrier opposite to those surfaces on which the coupling usually exerts a thrust for transmitting the driving torque.
An object of the present invention is to overcome the problems and limitations of prior art by providing a rotor less susceptible to wear and therefore having a longer service life. A further object of the present invention is to provide a pump that comprises said rotor and is reliable, with reduced weight and reduced cost.
These and other objects are achieved with the rotor and the pump comprising such rotor as claimed in the appended claims.

Summary of the Invention

The rotor according to the present invention comprises a vane carrier, a transmission coupling configured for transmitting a drive torque to the vane carrier, and at least one vane movably inserted in a suitable slot of the vane carrier. The van carrier comprises a seat having a blind bottom, preferably substantially perpendicular to a longitudinal axis of the rotor, and the transmission coupling comprises an engaging end configured for being inserted into the seat of the vane carrier. The engaging end of the transmission coupling comprises, in particular, a first face that is substantially parallel to the bottom of the seat, is oriented towards said bottom and is proximal thereto, and a second face oriented in a direction opposite to that of the first face.
According to the present invention, the vane carrier is preferably made of a thermoplastic material and the transmission coupling is preferably made of metal.
According to the present invention, the rotor further comprises a first support element. Said first support element comprises a base resting on the second face of the engaging end of the transmission coupling, and at least one first wing. The at least one first wing extends preferably substantially perpendicular to the base of the first support element and is arranged between a respective first thrust surface of the engaging end of the transmission coupling and a corresponding first abutment surface of the seat of the vane carrier, said first abutment surface facing the first thrust surface.
Advantageously, the at least one wing of the first support element allows limiting the wear due to the contact between the respective first thrust surface of the engaging end of the transmission coupling and the corresponding first abutment surface of the seat of the vane carrier. In this case, indeed, the contact takes place between two metal elements (namely, the first support element and the transmission coupling), preventing occurrence of the sliding friction component on the vane carrier.
According to the present invention, the rotor comprises a second support element comprising a base arranged between the bottom of the seat of the vane carrier and the first face of the engaging end of the transmission coupling.
Advantageously, the base of the second support element allows limiting the wear of the bottom of the seat of the vane carrier due to the first face of the engaging end of the transmission coupling because of axial pulsations of the transmission coupling.
According to a first embodiment of the invention, the second support element further comprises, preferably, at least one wing. The at least one wing preferably extends substantially perpendicular to the base of the second support element and is arranged between a respective second thrust surface of the engaging end of the transmission coupling and a corresponding second abutment surface of the seat of the vane carrier, said second abutment surface facing the second thrust surface.
Advantageously, the at least one wing of the second support element allows limiting the wear of the vane carrier due to the contact between the respective second thrust surface of the engaging end of the transmission coupling and the corresponding second abutment surface of the seat of the vane carrier. In this case too, indeed, the contact takes place between two metal elements (namely, the second support element and the transmission coupling), preventing occurrence of the sliding friction component on the vane carrier.
According to a second embodiment of the invention, the base of the first support element comprises at least one radial portion in which a radial slot is provided dividing the at least one radial portion into a first and a second sub-branch. A first and second wing extend respectively from said sub-branches, substantially perpendicularly to said sub-branches. Each first wing is arranged between a respective first thrust surface of the engaging end of the transmission coupling and a corresponding first abutment surface of the seat of the vane carrier, said first abutment surface facing the first thrust surface. Each second wing is arranged between a respective second thrust surface of the engaging end of the transmission coupling and a corresponding second abutment surface of the seat of the vane carrier, said second abutment surface facing the second thrust surface.
Advantageously, each first wing of the first support element according to the second embodiment allows limiting the wear of the vane carrier due to the contact between the respective first thrust surface of the engaging end of the transmission coupling and the corresponding first abutment surface of the vane carrier. In addition, advantageously, each second wing of the first support element allows limiting the wear due to the contact between the respective second thrust surface of the engaging end of the transmission coupling and the corresponding second abutment surface of the vane carrier. In this case too, indeed, the contact takes place between two metal elements (namely, the first support element and the transmission coupling), preventing occurrence of the sliding friction component on the vane carrier.
According to the invention, the first thrust surface is a rotational thrust surface configured for exerting a thrust onto said first abutment surface so as to transmit the driving torque to the vane carrier during normal operation of the pump. The said second thrust surface is a counter-rotational thrust surface configured for exerting a thrust onto said second abutment surface at the time when a reversal of the driving torque occurs.
According to a further embodiment, the functions of the first and second thrust surface are inverted, i.e. the first thrust surface is a counter-rotational thrust surface and the second thrust surface is a rotational thrust surface.
According to a further aspect of the present invention, the seat of the vane carrier and the engaging end of the transmission coupling have each a four-arm cross-shaped cross-section.
According to a further aspect of the present invention, the first and second support elements are made as thin metal plates.
According to a further aspect of the present invention, the first and second support elements are made of spring-steel.
A further object of the present invention is a pump comprising a rotor according to any of the features mentioned above.

Brief Description of the Drawings

These and other features and advantages of the present invention will become more apparent from the ensuing description of some preferred embodiments given by way of non-limiting examples with reference to the annexed figures, in which elements designated by the same or similar reference numerals indicate elements having the same or similar function and construction, and in which:

Figure 1 is a perspective view of a pump according to the present invention;
Figure 2 is an exploded perspective view of a rotor according to a first embodiment of the present invention;
Figure 3 is a top view of the rotor of Figure 2;
Figure 4 is a cross-sectional view of the rotor of Figure 3, taken along the line AA;
Figure 5 is a perspective view of a vane carrier of the rotor of Figure 2;
Figure 6 is a perspective view of a transmission coupling of the rotor of Figure 2;
Figure 7 is a perspective view of a first support element of the rotor of Figure 2;
Figure 8 is a perspective view of a second support element of the rotor of Figure 2;
Figure 9 is a perspective view of a first support element of a rotor according to a second embodiment of the present invention.

Description of Some Preferred Embodiments of the Invention

Referring to Figure 1, a pump according to the present invention is a vane pump 10 comprising a rotor 20 mounted within the pump 10 and configured for being driven by a drive member (not shown), such as, for example, a camshaft of a vehicle engine.
The rotor 20 according to a first embodiment, shown in Figures 2, 3 e 4, comprises a vane carrier 21, a transmission coupling 40, intended to transmit a driving torque provided by the drive member to the vane carrier 21, a vane (not shown), a first support element 70 and a second support element 60.
Referring in particular to Figures 2 and 5, the vane carrier 21, preferably made of a thermoplastic material, comprises a first cylindrical end 22 oriented towards the transmission coupling 40 and having a longitudinal axis Y, i.e. the axis of rotation of the rotor 20, and a second cylindrical end 23, coaxial to the first end 22 and preferably having an outer diameter larger than the outer diameter of the first end 22.
The second end 23 of the vane carrier 21 is radially crossed by a slot 24 in which the vane is movably mounted.
In the first end 22 of the vane carrier 21 there is provided a seat 25 having a blind bottom 26 and an open end 27 opposite to the blind bottom 26. The seat 25 has a cross-section shaped like a four-arm cross comprising a first, a second, a third and a fourth radial portion 29a-d. In particular, said radial portions 29a-d, diametrically opposed two by two, develop along two directions preferably orthogonal to each other. In addition, each of the above four radial portions 29a-d is preferably connected to two neighboring radial portions by means of arc-shaped portions 30. The blind bottom 26 of the seat 25 is substantially perpendicular to the longitudinal axis Y, whereas a plurality of walls of the seat 25 extend in a direction substantially parallel to the longitudinal axis Y. In particular, the first and the second radial portion 29a and 29b, diametrically opposite to each other, of the seat 25, have respective first walls 32 and second walls 33 extending from corresponding arc-shaped portions 30 to a respective peripheral wall 31 of said radial portions; these walls 32, 33 act as first abutment surfaces 32 and second abutment surfaces 33, respectively, against which the transmission coupling 40 exerts a thrust, as will be better illustrated below, so as to rotate the vane carrier 21.
The second end 23 of the vane carrier 21 further comprises a pin 34 arranged at the center of the seat 25 and extending from the bottom 26 of the seat 25 along the longitudinal axis Y. The pin 34 preferably has two portions with different diameters, i.e. a first portion 34a, proximal to the bottom 26 of the seat 25 and having a larger diameter, and a second portion 34b, distal to the bottom 26 of the seat 25 and having a smaller diameter.
Referring in particular to Figures 2 and 6, the transmission coupling 40, preferably made of steel or other material harder than that of the vane carrier, comprises an engaging end 41 configured for being inserted into the seat 25 of the vane carrier 21, and a coupling end 42, comprising coupling means 52 between the transmission coupling 40 and a camshaft end (not shown).
The engaging end 41 of the transmission coupling 40 has a four-arm cross-shaped cross-section, substantially equal to the cross-section of the seat 25 of the second end 23 of the vane carrier 21 and thus comprising a first, a second, a third and a fourth radial portion 44a-d. Similarly to what is provided for the radial portions 29a-d of the seat 25 of the vane carrier 21, the radial portions 44a-d of the transmission coupling 40 are arranged diametrically opposed two by two, develop along two directions preferably orthogonal to each other and each radial portion 44a-d is connected to two neighboring radial portions by means of arc-shaped portions 45.
The engaging end 41 further comprises a first face 46, substantially perpendicular to the longitudinal axis Y and oriented towards the bottom 26 of the seat 25 of the vane carrier 21 and proximal thereto, and a second face 47, also perpendicular to the longitudinal axis Y, said second face being opposite to the first face 46 and distal to the bottom 26 of the seat 25 of the vane carrier 21. The engaging end 41 further comprises walls extending between the first face 46 and the second face 47, substantially perpendicularly to said faces. In particular, the first and the second radial portion 44a and 44b, diametrically opposed to each other, have respective first walls 49 and second walls 50, extending from corresponding arc-shaped portions 45 to a respective peripheral wall 48 of said radial portions. The first walls 49, abutting against said first abutment surfaces 32 facing said first walls, exert, onto said first abutment surfaces, thrusts that cause rotation of the vane carrier 21; similarly, the second walls 50, abutting against said second abutment surfaces 33 facing said second walls, exert, onto said second abutment surfaces, thrusts that cause rotation of the vane carrier 21 in a direction opposite to the that of the rotation caused by the first thrust walls 49. In the following description, the first walls 49 will be referred to as first thrust surfaces 49 and the second walls 50 will be referred to as second thrust surfaces 50.
According to the illustrated embodiment, each first thrust surface 49 is a rotation thrust surface configured for exerting a thrust onto the respective first abutment surface 32 so as to transmit the driving torque to the vane carrier 21 during normal operation of the pump; each second thrust surface 50 is, instead, a counter-rotational thrust surface configured for exerting a thrust onto the respective second abutment surface 33 at the time when a reversal of the driving torque occurs.
According to a further embodiment, the functions of each first thrust surface 49 and each second thrust surface 50 are inverted, i.e. each first thrust surface 49 is a counter-rotational thrust surface and each second thrust surface 50 is a rotational thrust surface.
The engaging end 41 of the transmission coupling 40 further comprises a central opening 51 extending from the first face 46 to the second face 47 of the engaging end 41, along the longitudinal axis Y. The pin 34 of the vane carrier 21 is inserted through said opening 51. Preferably, said opening 51 is non-circular and it rather has an elongated shape. In particular, the opening 51 has a greater extension along a direction of development of the first radial portion 44a and the second radial portion 44b, diametrically opposed to each other, of the engaging end 41 of the transmission coupling 40. Advantageously, said elongated shape of the opening 51 allows some clearance between the transmission coupling 40 and the vane carrier 21, such as to compensate for any non-coaxiality between them.
In the coupling end 42 of the transmission coupling 40, the coupling means preferably have the shape of two teeth 52. Said teeth 52 extend parallel to the longitudinal axis Y, from the second face 47 of the engaging end 41 of the transmission coupling 40, at the third radial portion 44c and the fourth radial portion 44d of the engaging end 41. In particular, said third and fourth radial portions 44c, 44d are diametrically opposite radial portions of the engaging end 41 that are arranged transversely relative to the direction along which the opening 51 with elongated shape of the transmission coupling 40 has a greater extension. In a known manner, the teeth 52 are preferably configured for sliding in a corresponding slot (not shown) located at the end of the camshaft, thus forming an Oldham joint.
Referring in particular to Figures 2 and 7, according to the first embodiment of the invention, the first support element 70, made of a metal material, preferably spring-steel, and made as a thin metal plate, comprises a base 71 having a central bore 74 configured for being fitted with interference onto the second portion 34b of the pin 34 of the seat 25 of the vane carrier 21. The base 71 has a first radial portion 73a and a second radial portion 73b which are diametrically opposite to each other relative to the central bore 74 and rest on the second face 47 of the transmission coupling 40, in particular on the first radial portion 44a and on the second radial portion 44b of the engaging end 41, respectively.
Advantageously, the central bore 74, being made by deep drawing, has a longitudinal extension greater than the thickness of the first support element 70: such extension allows to obtain a large area of interference with the pin 34 in order to withstand axial and radial stresses transmitted by the transmission coupling 40.
Advantageously, the interference fitting between the first support element 170 and the second portion 34b of the pin 34 of the vane carrier 21 allows to prevent the transmission coupling 40 from slipping out of the vane carrier 21.
The first support element 70 further comprises a first wing 75 and a second wing 76, which are made as a single piece with the base 71. Said first wing 75 and second wing 76 extend from the first and second radial portion 73a, 73b of the base 71, respectively, in a direction substantially perpendicular to the base 71 and on the same side relative to a plane on which the base itself lies. The first and second wing 75, 76 are arranged between the first thrust surfaces 49 of the first radial portion 44a and of the second radial portion 44b, respectively, of the engaging end 41 of the transmission coupling 40 and the corresponding first abutment surfaces 32 of the seat 25 of the vane carrier 21. The two wings 75, 76 are thus arranged in diametrically opposite directions relative to the longitudinal axis Y.
Advantageously, the wings 75, 76 of the first support element 70 allow limiting the wear due to the contact between the first thrust surfaces 49 of the transmission coupling 40 and the corresponding first abutment surfaces 32 of the vane carrier 21, which first abutment surfaces face said first thrust surfaces.
Referring in particular to Figures 2 and 8, according to the first embodiment of the invention, the second support element 60, made of a metal material, preferably spring-steel, and being in the form of a thin metal plate, comprises a base 61 having the shape of a four-arm cross substantially equal to the shape of the cross-section of the seat 25 of the vane carrier 21. This base 61 therefore comprises a first, a second, a third and a fourth radial portion 163a-d, diametrically opposite two by two. The base 61 further has a central bore 64 configured for being fitted with interference onto the first portion 34a of the pin 34 of the vane carrier 21. Thanks to the fact that the second portion 34b of the pin 34 has a diameter smaller than that of the first portion, the insertion of the second support element 60 into the pin 34 is made easier.
Advantageously, the central bore 64, being made by deep drawing, has a longitudinal extension greater than the thickness of the second support element 60: such extension allows obtaining a large area of interference with the pin 34 in order to withstand the axial and radial stresses transmitted by the transmission coupling 40.
Advantageously, the base 61 of the second support element 60 allows to limit the wear of the bottom 26 of the seat 25 of the vane carrier 21 due to the first face 46 of the engaging end 41 of the transmission coupling 40 because of axial pulsations of the transmission coupling 40.
Preferably, the second support element 60 further comprises a first wing 65 and a second wing 66, which are made as a single piece with the base 61. Said first wing 65 and second wing 66 preferably extend from the first and second radial portion 63a, 63b of the base 61, respectively, in a direction substantially perpendicular to the base 61 and on the same side relative to a plane on which the base itself lies. The first and second wing 65, 66 are arranged between the second thrust surfaces 50 of the first radial portion 44a and of the second radial portion 44b, respectively, of the engaging end 41 of the transmission coupling 40 and the corresponding second abutment surfaces 33 of the seat 25 of the vane carrier 21. As the first and second radial portion 63a, 63b of the base 61 from which the two wings 65, 66 extend are opposite radial portions of the base 61, the two wings 65, 66 are arranged in diametrically opposite directions relative to the longitudinal axis Y.
Advantageously, the wings 65, 66 of the second support element 60 allow limiting the wear of the vane carrier 21 due to the contact between the second thrust surfaces 50 of the transmission coupling 40 and the corresponding second abutment surfaces 33 of the vane carrier 21, which second abutment surfaces face said second thrust surfaces.
According to a second embodiment of the invention, the first support element 170, shown in Figure 9, made of a metal material, preferably spring-steel, and made as a thin metal plate, comprises a base 171 having a central bore 174 configured for being fitted with interference onto the second portion 34b of the pin 34 of the vane carrier 21. The base 171 has a first radial portion 173a and a second radial portion 173b which are diametrically opposite to each other relative to the central bore 174 and rest on the second face 47 of the transmission coupling 40, in particular on the first radial portion 44a and on the second radial portion 44b of the transmission coupling, respectively.
Advantageously, the central bore 174, being made by deep drawing, has a longitudinal extension greater than the thickness of the first support element 170: such extension allows to obtain a large area of interference with the pin 34 in order to withstand axial and radial stresses transmitted by the transmission coupling 40.
The first support element 170 further comprises four wings 175, 176, 177, 178, made as a single piece with the base 171. In particular, a first wing 175 and a third wing 177 extend from the first radial portion 173a and a second wing 176 and a fourth wing 178 extend from the second radial portion 173b of the base 171. All the wings 175, 176, 177, 178 extend in a direction substantially perpendicular to the base 171 and on the same side relative to a plane on which the base itself lies. The first and the second wing 175, 176 are arranged between the first thrust surfaces 49 of the first radial portion 44a and of the second radial portion 44b, respectively, of the engaging end 41 of the transmission coupling 40 and the corresponding first abutment surfaces 32 of the seat 25 of the vane carrier 21, which first abutment surfaces face said first thrust surfaces, and thus lie in diametrically opposite directions relative to the longitudinal axis Y. The third and fourth wing 177, 178 are arranged between the second thrust surfaces 50 of the first radial portion 44a and of the second radial portion 44b, respectively, of the engaging end 41 of the transmission coupling 40 and the corresponding second abutment surfaces 33 of the seat 25 of the vane carrier 21, which second abutment surfaces face said second thrust surfaces, and thus lie in diametrically opposite directions relative to the longitudinal axis Y.
Advantageously, the first and the second wing 175, 176 of the first support element 170 allow limiting the wear of the vane carrier 21 due to the contact between the first thrust surfaces 49 of the transmission coupling 40 and the corresponding first abutment surfaces 32 of the vane carrier 21, which first abutment surfaces face said first thrust surfaces. In addition, advantageously, the third and fourth wing 177, 178 of the first support element 170 allow limiting the wear due to the contact between the second thrust surfaces 50 of the transmission coupling 40 and the corresponding second abutment surfaces 33 of the vane carrier 21, which second abutment surfaces face said second thrust surfaces.
In each of the two radial portions 173a, 173b of the first support element 170 there is further provided a radial slot 179 extending from a first closed end 184 proximal to the central bore 174 to an end 180 of the radial portion 173a, 173b distal to the central bore 174. Each slot 179 divides the respective radial portion 173a, 173b into a first sub-branch 181 and a second sub-branch 182, whereby each of the four wings 175, 176, 177, 178 extends from a respective sub-branch 181, 182. Preferably, each slot 179 has, at its closed end 184, a widened portion 185.
Owing to the slots 179, the sub-branches 181, 182 are elastic along the plane on which the base 171 lies, in a direction transverse to the corresponding wings (i.e. in the direction indicated by the arrow in Figure 9 for one of the sub-branches) and, furthermore, they are advantageously pre-loaded transversely outwards, so that the respective wings 175, 176, 177, 178 remain adhering against the corresponding first and second abutment surfaces 32, 33 of the vane carrier 21 rather than against the first and second thrust surfaces 49, 50 of the transmission coupling 40.
In other words, the elastic radial slots 179, combined with a width, under rest conditions, of the radial portions 173a, 173b of the support element 170 greater than the width of the corresponding radial portions 29a, 29b of the seat 25 of the vane carrier 21, allow inserting the first support element 170 and the transmission coupling 40 into the seat 25 of the vane carrier 21, ensuring that the wings 175, 176, 177, 178 of the first support element 170 are always in contact with the respective abutment surfaces 32, 33 of the vane carrier 21.
According to the second embodiment, the second support element (not shown) comprises, like the second support element of the first embodiment, a four-arm cross-shaped base arranged between the bottom of the seat of the vane carrier and the first face of the engaging end of the transmission coupling, and a central bore configured for being fitted with interference onto the first portion of the pin of the vane carrier. The second support element of the second embodiment differs from the first embodiment in that it does not have the wings perpendicular to the base.

Claims

Rotor comprising a vane carrier (21), a transmission coupling (40), configured for transmitting a driving torque to the vane carrier (21), and at least one vane; wherein the vane carrier (21) comprises a seat (25) having a blind bottom (26), and wherein the transmission coupling (40) comprises an engaging end (41) configured for being inserted into the seat (25) of the vane carrier (21) and having a first face (46) oriented towards the bottom (26) of the seat (25) of the vane carrier (21) and proximal thereto, and a second face (47) oriented in a direction opposite to that of the first face (46),
the rotor further comprising a first support element (70; 170) comprising a base (71; 171) resting on the second face (47) of said engaging end (41), and at least a first wing (75, 76; 175, 176) arranged between a respective first thrust surface (49) of the engaging end (41) and a corresponding first abutment surface (32) of the seat (25), said first abutment surface (32) facing the first thrust surface (49),

the rotor being characterized in that it comprises a second support element (60) comprising a base (61) arranged between the bottom (26) of the seat (25) of the vane carrier (21) and the first face (46) of the engaging end (41) of the transmission coupling (40).
Rotor according to claim 1, wherein the second supporting element (60) comprises at least one wing (65, 66) arranged between a respective second thrust surface (50) of said engaging end (41) and a corresponding second abutment surface (33) of said seat (25), said second abutment surface (33) facing the second thrust surface (50).
Rotor according to claim 1, wherein the base (171) of the first supporting element (170) comprises at least one radial portion (173a, 173b) in which a radial slot (179) is provided dividing said at least one radial portion (173a, 173b) into a first and a second sub-branch (181, 182), from which said first wing (175, 176) and a second wing (177, 178) extend, respectively, said second wing (177, 178) being arranged between a respective second thrust surface (50) of said engaging end (41) and a corresponding second abutment surface (33) of said seat (25), said second abutment surface (33) facing the second thrust surface (50).
Rotor according to claim 2 or 3, wherein:
said first thrust surface (49) is a rotational thrust surface configured for exerting a thrust onto said first abutment surface (32) so as to transmit the driving torque to the vane carrier (21), and said second thrust surface (50) is a counter-rotational thrust surface configured for exerting a thrust onto said second abutment surface (33) at the time when a reversal of the driving torque occurs; or

said second thrust surface (50) is a rotational thrust surface configured for exerting a thrust onto said second abutment surface (33) so as to transmit the driving torque to the vane carrier (21), and said first thrust surface (49) is a counter-rotational thrust surface configured for exerting a thrust onto said first abutment surface (32) at the time when a reversal of the driving torque occurs.
Rotor according to any of the preceding claims, wherein the seat (25) of the vane carrier (21) and the engaging end (41) of the transmission coupling (40) have each a four-arm cross-shaped cross-section.
Rotor according to any of the preceding claims, wherein said first and second supporting elements (60, 70; 170) are made as thin metal plates.
Rotor according to any of the preceding claims, wherein said first and second supporting elements (60, 70; 170) are made of spring-steel.
Rotor according to any of the preceding claims, wherein the vane carrier (21) is made of thermoplastic material and the transmission coupling (40) is made of metal.
Pump comprising a rotor according to any of the preceding claims.