The invention relates to an electric motor.
Electric motors comprising rotor guide means and housing elements are already known. It is also known that the housing elements are produced by means of diecasting, in particular zinc, aluminum or magnesium diecasting. Diecasting is used to produce housing elements that have sufficient stability. Housing elements formed by diecasting, however, are heavy and expensive.
The electric motor according to the invention has the advantage of a simplified and thus economical production of the electric motor. A further advantage is considered to be the fact that, due to the use of a bent sheet metal part, in particular a deep-drawn sheet metal as housing element, less material is required compared to the diecast housing element, and therefore the weight of the housing element and of the electric motor can be reduced. Furthermore, the production of a bent sheet metal part is less complex and thus more convenient compared to the production of a cast part.
It is particularly advantageous that the carrier means has a first recess, which in particular is continuous. Furthermore, the rotor guide means is mounted in the first recess in the carrier means in a rotationally fixed or rotatable manner. By accommodating the rotor guide means in a recess in the carrier means, the stability of the electric motor can be increased. It is also advantageous that the assembly and thus the production of the electric motor can be simplified.
An advantageous development is characterized in that the rotor guide means and the carrier means are connected, in particular in a form-locked and/or force-locked manner. Due to the force-locked and/or form-locked connection of the carrier means to the rotor guide means, a rotationally fixed connection between the carrier means and the rotor guide means is achieved. A rotationally fixed connection of the carrier means to the rotor guide means is advantageous for certain electric motor mountings, in particular external rotor motors. In order to increase the stability, it is also advantageous for the rotor guide means to be press fitted or cast in into the first recess in the carrier.
An advantageous development is that the carrier means has a bearing element. In particular, the bearing element is arranged in the first recess in the carrier means. The bearing element guides, in particular supports, the rotor guide means rotatably relative to the carrier means. The rotatable mounting of the rotor guide means relative to the carrier means is advantageous for electric motors which have an internal rotor in relation to the stator.
A development of the invention is that the electric motor has a stator. The stator is in particular connected to the carrier means in a form-locked and/or force-locked manner. Due to the form-locked and/or force-locked connection between the stator and the carrier means, forces or torques that occur between the rotor and the stator during operation or standstill can be optimally transferred.
It is particularly advantageous that the carrier means has an orientation means which orientates, in particular centers, the stator relative to the rotor guide means. The assembly of the individual elements of the motor is simplified by the orientation means on the carrier means, which results in an accelerated production of the electric motor. The carrier means can advantageously have an orientation means which implements an orientation relative to the housing element.
An advantageous development of the invention is that the electric motor has a connection means, wherein the connection means connects the carrier means to the housing element and/or a stator in a form-locked and/or force-locked manner. Connection of the carrier means to the housing element and/or the stator is possible in a simple manner by the connection means.
It is also advantageous that the connection means is formed as a screw, in particular as a self-tapping screw. It is also advantageous that the carrier means has a second recess, which in particular is continuous, wherein the connection means and the second recess cooperate, the connection means in particular engaging in the second recess. The stability of the electric motor is improved by the cooperation of the second recess in the carrier means with the connection means.
An advantageous development is that the housing element has a recess, wherein the recess cooperates with the connection means. The stability of the electric motor is improved by the cooperation of the recess in the housing element with the connection means. Elements of the electric motor can also be connected to the housing element. It is advantageous in particular when the recess is formed as a passage in the sheet metal of the housing element. The design of the recess as a passage enables a simple production of a recess that enables the best possible, in particular stable connection between the housing element and the connection means.
It is advantageous that the carrier means has at least one spoke. It is also advantageous when the carrier means has a middle element, wherein the middle element has a first recess. The spoke is arranged on the middle element. The at least one spoke, together with the middle element, increases the stability of the carrier means. Forces or torques created at standstill or during operation can be optimally absorbed or emitted by the carrier means.
It is particularly advantageous that the spoke has a second recess, which in particular is continuous, for connection of the carrier means to the housing element and/or the stator. The second recess cooperates with a connection means, in particular a screw, preferably a self-tapping screw. The arrangement of a second recess in the spoke and the cooperation of the second recess with a connection means enables an optimal absorption and emission of forces or torques into or from the connection means.
A preferred development of the invention is that the electric motor has control electronics, and the control electronics are arranged on the housing element, in particular the housing element is part of the housing of the control electronics.
Exemplary embodiments of the invention are illustrated in the drawings and will be explained in greater detail in the following description. In the drawings:
Electronically commutated electric motors belong to the group of synchronous DC motors, that is to say an electromagnetic rotary field generated by stator coils 22 has the same rotational speed as a rotor 24. In order to generate a rotational movement, the stator coils 22 must be energized in a specific sequence. The generated magnetic field in the stator coils 22 leads to an attraction or repulsion of the magnets 26 of the rotor 24 and therefore to a rotation of the rotor 24. This sequence is generated by electronics, in particular control electronics.
The electronics are arranged on a housing element 10 (see
The rotor 24 is arranged rotatably relative to the stator 20 via the rotor guide means 25. During operation or at standstill, forces and torques act between the rotor 24 and the stator 20. These forces and torques also act on devices or elements connected to the electric motor 1. If the stator 20 is mounted in particular on a housing element 10, the forces and torques will be transferred thereto. Conversely, forces and torques are transferred from the housing element 10 to the stator 20 and/or the rotor 24. For this reason, the rotor 24, the stator 20, and further elements of the electric motor 1 must have sufficient stability to be able to absorb and/or transfer the forces or torques occurring at standstill or during operation.
By way of example, the housing element 10 is part of a housing 5, in particular a casing, a transmission, electronics, or a fan housing. The housing element 10 serves in particular to secure the electric motor 1 to a casing, a transmission, electronics, or a fan housing. Forces or torques from outside the electric motor 1 act on the housing element 10. The housing element 10 also transfers forces which for example act on the rotor 24 to the surrounding environment, in particular a casing, a transmission, or a fan housing.
The purpose of the housing element 10 is, amongst other things and besides the heat dissipation and protection of the electronics, the rotor 24, or the stator 20, to also transfer forces that act on the electric motor 1 from outside the electric motor 1, and vice versa.
In the prior art, housing elements 10 produced from diecast aluminum are used in accordance with
The housing element 10 has at least one recess 12, in particular a passage or a bore. The recess 12 cooperates with a connection means 50 (see
In accordance with one embodiment, the housing element 10 according to
It is particularly advantageous that the carrier means 40, which in particular is formed as a sintered part, has a coefficient of expansion substantially identical to that of a rotor guide means 25 made of steel.
In accordance with the exemplary embodiment in
The spokes enable an improved distribution of the force over the housing element 10, and vice versa. The spokes 42 have a length dependent on the torque and the force. The spokes 42 each have a second recess 45. The second recess 45 is arranged at the end of the corresponding spoke 42 averted from the rotor guide means 25. The spokes 42 also have a spoke head 46. The spoke head 46 comprises the second recess 45. The spoke head 46 is connected to the middle element 41 via a spoke rib 43. The spoke heads 46, the spoke ribs 43, and the middle element 41 of the carrier means 40 are formed in one piece.
The spokes 42 are advantageously arranged at a uniform angle to one another. By way of example, in the case of a carrier means 40 having three spokes 42, the spokes 42 are arranged at an angle of 120 degrees to one another. In the case of a carrier means 40 having four spokes 42, the spokes 42 are arranged at an angle of 90 degrees to one another. By means of a uniform arrangement of the spokes 42, forces that act on the housing element 10 via the rotor guide means 25 and vice versa can be distributed in the best possible way.
The connection means 50 is formed in particular as a screw with a thread, advantageously as a self-tapping screw. Self-tapping screws or thread-forming screws are connection means 50 which, when screwed into a core hole, produce their female thread themselves by chipless shaping. The connection means 50 provides a form fit and/or a force fit between the stator 20, the carrier means 40, and the housing element 10.
In accordance with the invention, the connection means 50 can provide a form fit and/or force fit between the carrier means 40 and the housing element 10.
In accordance with a further embodiment the recess 12 in the housing element 10 has a thread, and the connection element 50 has a thread corresponding to the thread of the housing element 10.
In accordance with one embodiment the recess 12 of the housing element 10 is formed as a passage.
In accordance with
The carrier means 40 comprises a first recess 44. One or more bearing elements 48 can be arranged in the first recess 44. In accordance with
The carrier element 40 is connected to the housing element 10 via the connection means 50. The carrier means 40 is secured to the housing element 10. The housing element 10 has recesses 12. The recesses 12 are formed in particular as a passage. They also have an inner diameter smaller than the outer diameter of the connection means 50. The connection means 50 is formed in particular as a self-tapping screw having a self-tapping thread 44. The thread 44 of the self-tapping screw 44 creates its female thread itself by chipless shaping.
In accordance with a further embodiment the recesses in the housing element 10 have threads. These threads cooperate with the thread of the connection means 50, in particular of the screws.
A partly assembled electric motor 1 is illustrated in
In accordance with
The connection means 50 are formed in particular as screws, advantageously as self-tapping screws. The connection means 50 connect the stator 20, the carrier means 40, and the housing element 10 to one another in a force-locked and/or form-locked manner.
A second bearing element 48b is arranged inside a recess 27 in the stator 20. A tolerance ring 28 is arranged between the stator 20 and the bearing element 48b. The tolerance ring enables the compensation of tolerances in the production of the stator 20 and the bearing element 48. The stator 20 and the bearing element 48 also have different coefficients of expansion. The different coefficients of expansion can also be compensated for by the tolerance ring 28.
The connection means 50, in particular screws, connect the stator 20, the carrier means 40 and the housing element 10. The connection means 50 enable the stator 20 and the carrier means 40 to be secured to the housing element 10.
In accordance with one embodiment the carrier means 40 comprises an orientation means 49. An orientation means 49 is arranged on each spoke head 46 in
In accordance with a further exemplary embodiment the connection means 50 is embodied in the form of rivets or clips. In accordance with the invention, the connection of the carrier means 40 to the housing element 10 can also be implemented in particular by means of welding, soldering or adhesive bonding.
In accordance with a further exemplary embodiment the housing element 10 is part of an electric motor housing 5 surrounding the electric motor 1.
In accordance with a further embodiment the carrier means 40 is formed as a sheet metal part, in particular a deep-drawn sheet metal part, or as a diecast part, in particular made of zinc, aluminum or magnesium.
The connection means 50 advantageously has a seal, in particular a microencapsulation. The seal prevents an exchange of fluids between the region of the stator and the region of the housing element 10. A seal of this type is important in particular when the housing element 10 is part of a housing 5 that surrounds electronics.
In accordance with further embodiments the spokes 42 are arranged at an angle of from 30 to 180 degrees to one another. The angle is dependent on the number of spokes 42. The angles between the spokes 42 are advantageously substantially identical. The angle varies depending on the number of spokes 42, advantageously in steps/increments of 30 degrees. By way of example, the angle between the spokes 42 in the case of a carrier means 40 having four spokes 42 corresponds to 90 degrees, and in the case of a carrier means 40 having 12 spokes the angle corresponds to 30 degrees. A carrier means 40 having substantially identical angles between the spokes 42 has improved magnetic properties.
An electric motor 1 according to the invention can be embodied in particular as a brush motor, brushless motor, asynchronous motor, synchronous motor, electrically commutated motor, or as a stepper motor.
Number | Date | Country | Kind |
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10 2014 211 109.9 | Jun 2014 | DE | national |
Filing Document | Filing Date | Country | Kind |
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PCT/EP2015/058629 | 4/22/2015 | WO | 00 |