WO2011107407A2

WO2011107407A2 - Electric motor structure, particularly for gear motors for window winders, seats, windscreen wipers, and other applications in vehicles

Info

Publication number: WO2011107407A2
Application number: PCT/EP2011/052845
Authority: WO
Inventors: Maurizio Basso; Andrea Miazzo; Mirko Ortoman; Antonio Surian
Original assignee: Nuova Sme S.P.A.
Priority date: 2010-03-01
Filing date: 2011-02-25
Publication date: 2011-09-09
Also published as: ITPD20100012U1; DE112011100738T5; WO2011107407A3

Abstract

An electric motor structure (10), particularly for gear motors for window winders, seats, windscreen wipers, and other applications in vehicles, which comprises: a carcase (11), for containing the stator and rotor, a drive shaft (12) with commutator (13) and corresponding brushes (14, 15), and with a cylindrical magnet (16) and at least one corresponding Hall effect sensor (17) for detecting the rotary motion of the drive shaft, an electronic card (19) with a position that is substantially orthogonal to the axis of rotation (20) of the drive shaft (12), on the electronic card (19) there being arranged the brushes and the at least one sensor with the respective power and signaling lines, a cover (22) for closing the carcase (11). The at least one Hall effect sensor (17) is housed, and stably kept in the correct operational condition, in a corresponding complementarity shaped centering seat (23) which is directly formed, alternatively, either on the cover (22) for closing the carcase or on the body of the connector element (21).

Description

ELECTRIC MOTOR STRUCTURE, PARTICULARLY FOR GEAR MOTORS FOR WINDOW WINDERS, SEATS, WINDSCREEN WIPERS,

AND OTHER APPLICATIONS IN VEHICLES

Technical field

The present invention relates to an electric motor structure, particularly for gear motors for window winders, seats, windscreen wipers, and other applications in vehicles.

Background Art

Nowadays electric motors, with associated gear reducers, are known and very widespread in application for example in motor vehicles, for moving window winders, windscreen wipers, parts of seats and the like, the principal characteristic of which is compactness.

Indeed, such electric motors are adapted to be accommodated in narrow spaces like the inside of a car door, or in the rear boot door, or in the engine bonnet of a vehicle.

In view of the ever increasing demand by purchasers to have vehicles, such as cars, off-road vehicles, but also boats, which are provided with servoassisted devices, such as, for example, but not only, window winders, windscreen wipers and the like, and in view therefore of the constant increase in demand for such compact electric motors, nowadays in the sector the need is increasingly felt to automate the production of such compact electric motors, so as to respond as quickly as possible to the rapid changes of the market, while at the same time keeping costs down to levels that are highly competitive.

Disclosure of the Invention

The aim of the present invention is to provide an electric motor structure, particularly for gear motors for window winders, seats, windscreen wipers, and other applications in vehicles, the assembly of which lends itself well to being completely automated or semi-automated, and in any case more automated than known systems for assembling electric motors.

Within this aim, an object of the present invention is to develop an electric motor structure with performance levels that are not lower than similar electric motors of the known type.

Another object of the invention is to provide an electric motor structure with dimensions that are not dissimilar to, and in any case not greater than, those of known compact electric motors of equal performance.

Another object of the invention is to provide an electric motor structure, particularly for gear motors for window winders, seats, windscreen wipers, and other applications in vehicles, which can be produced using known systems and technologies.

This aim, as well as these and other objects which will become better apparent hereinafter, are achieved by an electric motor structure, particularly for gear motors for window winders, seats, windscreen wipers, and other applications in vehicles, that comprises

- a carcase, for containing the stator and rotor,

- a drive shaft with commutator and corresponding brushes, and with a cylindrical magnet and at least one corresponding Hall effect sensor for detecting the rotary motion of said drive shaft,

characterized in that it has

- an electronic card with a position that is substantially orthogonal to the axis of rotation of the drive shaft, on said electronic card there being arranged said brushes and said at least one sensor with the respective power and signaling lines,

- a connector element for the electric power supply of the electric motor structure, holding said electronic card

- a cover for closing the carcase,

said at least one Hall effect sensor being housed, and kept in a stable condition, in a corresponding complementarily shaped seat formed, alternatively, either on said cover for closing the carcase or on the body of the connector element.

Brief description of the drawings

Further characteristics and advantages of the invention will become better apparent from the following detailed description of three preferred, but not exclusive, embodiments of the electric motor structure according to the invention, illustrated by way of non-limiting example in the accompanying drawings, wherein:

Figure 1 is an exploded perspective view of an electric motor structure according to the invention in a first embodiment thereof;

Figure 2 is a perspective view of a portion of the electronic card;

Figure 3 is a different perspective view of the same portion of the electronic card of Figure 2;

Figure 4 is a partial side view of the electric motor structure according to the first embodiment of the invention;

Figure 5 is a sectional view taken along the line V-V of Figure 4;

Figure 6 is a sectional view taken along the line VI- VI of Figure 4; Figure 7 is a partially-exploded perspective view of the cover, the electronic card and the connector element of a structure according to the invention in a second embodiment;

Figure 8 is a different perspective view of what is shown in Figure 7;

Figure 9 is a longitudinal sectional view passing through the axis of the motor of the electric motor structure according to the invention, in the second embodiment thereof;

Figure 10 is a detail of a cross-sectional view of the electric motor structure according to the invention, in its second embodiment;

Figure 11 is an exploded perspective view of the electric motor structure according to the invention in a third embodiment thereof;

Figure 12 is a different partially-exploded perspective view of the electric motor structure according to the invention in its third embodiment;

Figure 13 is a side view of a detail of the electric motor structure according to the invention in its third embodiment;

Figure 14 is a sectional view taken along the line XIV-XIV of Figure

13.

Ways of carrying out the Invention

With reference to the figures, an electric motor structure, particularly for gear motors for window winders, seats, windscreen wipers, and other applications in vehicles, is generally indicated in its first embodiment with the reference numeral 10.

The electric motor structure 10 comprises:

- a carcase 11 , for containing a stator and a rotor, such items not being shown and being understood as per se known,

- a drive shaft 12 with commutator 13 and corresponding brushes 14 and 15, and with a cylindrical magnet 16 and two corresponding Hall effect sensors 17 and 18 for detecting the rotary motion of the drive shaft 12,

- an electronic card 19 with a position that is substantially orthogonal to the axis of rotation 20 of the drive shaft 12, on the electronic card 19 there being arranged the brushes 14 and 15 and the sensors 17 and 18 with the respective power and signaling lines,

- a connector element 21 for the electric power supply of the electric motor structure, the connector element 21 being shaped in order to hold the electronic card 19;

- a cover 22 for closing the carcase 11 and for protecting the electronic card 19.

The distinctive characteristic of the electric motor structure 10 according to the invention consists in that the Hall effect sensors 17 and 18 are housed, and stably kept therein in the correct operating condition, in a corresponding complementarily shaped centering seat 23 and 24 respectively, which is formed directly, alternatively, either on such cover for closing the carcase or on the body of the connector element.

On the body of the connector element 21 there is a seat 12a for a bushing 12b for centering the drive shaft 12, inside a cap 27, substantially cylindrical, for protecting the magnet 16 and the commutator 13.

The position of the bushing 12b, typically essential to the correct centering of the drive shaft and normally associated and housed, in known electric gear motors, in the casing of the gear reducer assembly, makes it possible to optimize the centering in proximity to the exact region where greater precision is necessary, i.e. the region of the Hall sensors and of the brushes, as well as cooperate with an increased automation of the structure according to the invention.

In this first embodiment of the invention, which is understood to be a non-limiting example thereof, the centering seats 23 and 24 are formed in the cover portion 22a that is designed to protect the electronic card 19 around the drive shaft 12 and at the carcase 11, as can clearly be seen in the sectional views of Figures 5 and 6.

In particular, the connector element 21 has a body made of plastics, which comprises a part that is substantially cylindrical 21a and provided with a bottom 21b and which is designed to be positioned so as to close the carcase 11, and, in a single body, a part 21c that is substantially parallelepiped which is designed to receive the connection terminals 26 which are pre-mounted on the card 19.

In this first embodiment, the electrical socket of the connector element 21 is thus formed upon the act of inserting the electronic card 19 into the body of the connector element 21.

The substantially cylindrical part 21a centrally has a cap 27, substantially cylindrical, to protect the magnet 16 and the commutator 13, the cap 27 having lateral windows 28 for access to the commutator 13 for the brushes 14 and 15.

In this first embodiment of the invention, the Hall effect sensors 17 and 18 are fixed to the electronic card 19 by tinning the pins 17a and 18a so that the sensors are arranged substantially parallel to the axis of the motor and are correctly facing toward the magnet 16, an arrangement which they must stably maintain in order to be able to operate correctly.

The operations for tinning the pins of the sensors can be performed automatically with known techniques.

The provision within the cover 22 of appendages 30 and 31 , which define the seats 23 and 24 for the sensors 17 and 18, makes it possible to protect and ensure the position of the sensors with respect to the magnet 16, by using the bodies made of plastics which are already part of the electric motor, such as the cover 22 or the body of the connector element 19, without having to provide special containers which would then need to be manually mounted on some part of the existing electric motor, with expenditure of time and labour.

For example, for the electric motor structure 10, the improved assembly sequence involves the coupling, in the axial direction,

- of the electronic card 19, with the Hall sensors 17 and 18 and the brushes 14 and 15 already on board, into the connector element 19,

- of the connector element 19 with the carcase 11 ,

- and the closing, still in the axial direction, of the connector element 19 with the cover 22.

The electric motor structure 10 described therefore makes it possible, without increasing the number of components of the electric motor, to automate and speed up its assembly without compromising the correct functionality of the final product.

In the first embodiment of the invention, the brushes 14 and 15 are each held by a corresponding leaf spring 33 and 34.

Each of the leaf springs 33 and 34 is made of sheet metal, and is fixed by a first fin 35 to the electronic card 19. Each leaf spring has a second, opposite fin 36 which is designed to be inserted into a corresponding locking slot 37 formed on a pre-arranged portion of the body of the connector element, specifically, in this embodiment, on the bottom 21b of the cylindrical part 21a of the body of the connector element 21.

In this way it is possible to adopt the solution with brushes on leaf springs, which in and of itself is cheaper than the solution with brushes in corresponding brush guides, pushed by a further elastic pusher element, thus obviating the usual problems of correct positioning and pushing direction. Indeed, the precision of mounting of the leaf spring 33 and 34 on the electronic card 19 is then maintained and ensured by the coupling between the second fms 36 and the bottom 21b of the connector body, which in turn is normally centered with respect to the carcase and the drive shaft, the correct position thus being ensured as well as the preferred pushing direction of the leaf spring, and of the brush held, toward the commutator.

The electric motor structure 10 according to the invention, precisely because of the importance of ensuring the relative positions of the principal components, has centering means for the correct positioning of the electronic card 19 with respect to the drive shaft 12 and with respect to the connector element 21.

In this first embodiment of the invention, the centering means are provided by a series of appendages 40, for example cylindrical as in Figure 1, protruding from the bottom of the body of the connector element 21 in a direction parallel to the axis 20 of the motor, and adapted to cooperate with complementarity shaped holes 41 defined on the electronic card 19.

A second embodiment of the electric motor structure according to the invention is shown in Figures 7 to 10 and is indicated therein with the reference numeral 110.

In this second embodiment of the invention, the brushes 114 and 1 15 are mounted on the electronic card 119 in corresponding brush-holder guides 133 and 134, and are pushed by one end of a helical spring, respectively 136 and 137.

In this second embodiment, there is a Hall sensor 117, tinned to the electronic card 119 in the manner as described previously for the first embodiment of the invention, housed, and stably kept therein in the correct operating condition, in a corresponding complementarily shaped centering seat 123 which is formed directly on the cover 122.

In this specific embodiment, the centering seat 123 is provided by a recess formed within the cover 122.

In Figure 9 the Hall sensor 117 can clearly be seen with the pins 117a tinned to the electronic card 119 and facing toward the magnet 116.

From the cross-section of Figure 10 it can be seen how the centering seat 123 has a rear ribbing 123a and a front abutment 123b which are adapted to ensure the position of the sensor 117, by impeding any movement thereof and in particular movements in a radial direction.

In this second embodiment, the seat 112a for the bushing 112b for centering the drive shaft is provided in the cover 122, as can be clearly seen in Figure 9.

In this second embodiment of the invention the connector element

121 is completed with the terminals 126 before it is mounted on the card, and it is mounted on the electronic card 119 so as to be able to be assembled with the carcase 11 1 and the cover 122 in the same operations to assemble the carcase 111, the card 119 and the cover 122.

In this second embodiment of the invention, the centering means are provided by an annular portion 119a with outer circular perimeter of the electronic card 119.

The annular portion 119a is designed to surround the drive shaft 112 and to be inserted into a corresponding complementarily shaped space 122a in the cover 122 for closing the carcase 11 1, the circular outer edge 119b of the annular portion 119a of the card being designed to cooperate with the inner surface 122b of the cylindrical wall of the space 122a in order to achieve the centering between the electronic card and the carcase cover.

A third embodiment of the electric motor structure according to the invention is shown in Figures 1 1 to 14 and is indicated therein with the reference numeral 210.

In this third embodiment, the electronic card 219 is designed to be inserted radially into the body of the connector element 221.

The electronic card 219 on one side has two Hall sensors 217 and 218, and on the opposite side two brushes 214 on corresponding leaf springs 233 as described for the first embodiment of the present invention.

In this specific third embodiment, the centering seats 223 and 224 are defined on a closing cover 222 which is integrated, thus forming part thereof in a single body of plastics, in a housing for the reduction gears 250, which is designed to be fixed to the carcase 211.

From Figures 12 and 14 it can easily be seen that the seats 223 and 224 are formed in an appendage 231 which extends from the inner surface of the cover 222 and in a single body with it and therefore with the housing 250.

For this third embodiment of the invention, the centering means are provided by two appendages with an elastically deformable head 251 designed to snap-fit into a corresponding hole 252 on the electronic card 219, and by two rivets which are adapted to pass through the card 219 at corresponding dedicated through holes 254 and to engage with corresponding tubular protrusions 255, which are also support spacers for the card, extending from the body of the connector element 221.

The electric motor structure according to the invention is intended to have a drive shaft with a diameter comprised in an interval between 3.5 mm and 6 mm.

Moreover, the electric motor structure according to the invention is intended to have a cylindrical magnet with a diameter comprised in an interval between 9 mm and 14.5 mm.

Moreover, the electric motor structure according to the invention is intended to have two brushes arranged radially at a mutually angular distance comprised between 80° and 180°. In practice it has been found that the invention fully achieves the intended aim and objects.

In particular, the invention provides an electric motor structure, particularly for gear motors for window winders, seats, windscreen wipers, and other applications in vehicles, the assembly of which lends itself well to being completely automated or semi-automated, and in any case more automated than known systems for assembling electric motors.

Moreover, the invention provides an electric motor structure with performance levels that are not lower than similar electric motors of the known type.

Moreover, the invention provides an electric motor structure with dimensions that are not dissimilar to, and in any case not greater than, those of known compact electric motors of equal performance.

Furthermore, the invention provides an electric motor structure, particularly for gear motors for window winders, seats, windscreen wipers, and other applications in vehicles, which can be produced using known systems and technologies.

The invention thus conceived is susceptible of numerous modifications and variations, all of which are within the scope of the appended claims. Moreover, all the details may be substituted by other, technically equivalent elements.

In practice the materials employed, as well as the contingent dimensions and shapes, may be any according to requirements and to the state of the art.

The disclosures in Italian Utility Model Application No.

PD2010U000012 from which this application claims priority are incorporated herein by reference.

Where technical features mentioned in any claim are followed by reference signs, such reference signs have been inserted for the sole purpose of increasing the intelligibility of the claims and accordingly such reference signs do not have any limiting effect on the interpretation of each element identified by way of example by such reference signs.

Claims

1. An electric motor structure (10), particularly for gear motors for window winders, seats, windscreen wipers, and other applications in vehicles, which comprises

- a carcase (11), for containing the stator and rotor,

- a drive shaft (12) with commutator (13) and corresponding brushes (14, 15), and with a cylindrical magnet (16) and at least one corresponding Hall effect sensor (17) for detecting the rotary motion of said drive shaft, characterized in that it has

- an electronic card (19) with a position that is substantially orthogonal to the axis of rotation (20) of the drive shaft (12), on said electronic card there being arranged said brushes and said at least one sensor with the respective power and signaling lines,

- a connector element (21), for the electric power supply of the electric motor structure,

- a cover (22) for closing the carcase (11),

said at least one Hall effect sensor (17) being housed, and stably kept in the correct operational condition, in a corresponding complementarily shaped seat (23) which is directly formed, alternatively, either on said cover (22) for closing the carcase or on the body of the connector element (21), on said cover (22) or on said body of the connector element (21) there being formed a seat (12a) for a bushing (12b) for centering the drive shaft (12).

2. The electric motor structure according to claim 1 , characterized in that said at least one Hall effect sensor is fixed to the electronic card by tinning in such a way as to be arranged substantially parallel to the axis of the motor.

3. The electric motor structure according to the preceding claims, characterized in that said brushes are mounted on said electronic card in corresponding brush-holder guides and are pushed by one end of a helical spring.

4. The electric motor structure according to claims 1 and 2, characterized in that said brushes are each held by a corresponding leaf spring, each leaf spring being fixed by a first fin to said electronic card, and having a second, opposite fin which is designed to be inserted into a corresponding locking slot formed on a pre-arranged portion of the body of the connector element.

5. The electric motor structure according to the preceding claims, characterized in that it has centering means for the correct positioning of said electronic card with respect to the drive shaft and with respect to the connector element.

6. The electric motor structure according to claim 5, characterized in that said centering means are provided by a series of appendages protruding from the body of said connector element and are adapted to cooperate with complementarily shaped holes defined on said electronic card.

7. The electric motor structure according to claim 5, characterized in that said centering means are provided by an annular portion with at least partially circular outer perimeter of said electronic card, which is designed to be inserted into a corresponding complementarily shaped space in said cover for closing the carcase, the circular outer edge of said annular portion of the card being designed to cooperate with the inner surface of the cylindrical wall of said space in order to achieve the centering between the electronic card and the carcase cover,

8. The electric motor structure according to claim 5, characterized in that said centering means are provided by at least one elastically deformable appendage for snap-fitting into a corresponding hole in said electronic card,

9. The electric motor structure according to the preceding claims, characterized in that said centering means comprise at least one rivet which is adapted to pass through said card at a dedicated through hole and to engage with a tubular protrusion for supporting said card extending from the body of said connector element.

10. The electric motor structure according to the preceding claims, characterized in that it has a rotor with at least eight slots.

11. The electric motor structure according to the preceding claims, characterized in that the diameter of said drive shaft is comprised between 3.5 mm and 6 mm.

12. The electric motor structure according to the preceding claims, characterized in that the diameter of said cylindrical magnet is comprised between 9 mm and 14.5 mm.

13. The electric motor structure according to the preceding claims, characterized in that it has two brushes arranged radially at a mutually angular distance comprised between 80° and 180°.