Patent Publication Number: US-2022231569-A1

Title: Contact Pin, Support Board and Electrical Machine

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This is a U.S. national stage of application No. PCT/EP2020/064389 filed 25 May 2020. Priority is claimed on Austria Application No. A50496/2019 filed 29 May 2019, the content of which is incorporated herein by reference in its entirety. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The invention relates to a contact pin for an electric machine. 
     2. Description of the Related Art 
     Particularly in vehicle electronics, there is frequently the need to integrate devices with control electronics into a motor, into a transmission, etc., in order to make as good use as possible of limited installation space and to keep cable runs short. Interface components such as contact pins, are in this case exposed to significant loads. 
     WO 2018/114349 A1, for example, discloses an electric machine having a cooling device. Here, a plug connector is connected to a support plate. However, it is not apparent to what extent this plug connector is designed appropriately in terms of load-bearing capacity with respect to possible relative movements between the plug connector and devices that may be connected thereto. 
     SUMMARY OF THE INVENTION 
     It is an object of the to provide a contact pin that is highly suitable for locally different mechanical and/or thermal loads. 
     This and other objects and advantages are achieved in accordance with the invention by a contact pin of the type mentioned at the beginning, where at least one first component longitudinal portion and one second component longitudinal portion are provided, where the first component longitudinal portion has a greater level of rigidity than the second component longitudinal portion. 
     As a result, little contact-zone wear is brought about between the contact pin and components or devices connected thereto, with, at the same time, favorable mounting properties. The first component longitudinal portion of the contact pin is formed in a rigid manner so that it can be pressed, for example, into a support plate. 
     The second component longitudinal portion of the contact pin is less rigid than the first component longitudinal portion and, depending on the loads acting on it (for example, mechanical loads on account of relative movements between components connected to the contact pin or thermal loads on account of heat transmission from the connected components to the contact pin), can elastically deform. 
     Depending on the type of loads, the greater rigidity of the first component longitudinal portion, or the lower rigidity of the second component longitudinal portion, can be, for example, flexural rigidity and/or torsional rigidity. A low level of rigidity of the second component portion can be achieved, for example, because it is in manner so as to bend in multiple opposite directions, has a plurality of recesses and/or is formed in a manner so as to include multiple slots. 
     Other objects and features of the present invention will become apparent from the following detailed description considered in conjunction with the accompanying drawings. It is to be understood, however, that the drawings are designed solely for purposes of illustration and not as a definition of the limits of the invention, for which reference should be made to the appended claims. It should be further understood that the drawings are not necessarily drawn to scale and that, unless otherwise indicated, they are merely intended to conceptually illustrate the structures and procedures described herein. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The invention is explained in more detail in the following text on the basis of exemplary embodiments, in which: 
         FIG. 1  shows a schematic side elevation of a machine having a support plate and contact pins in a sectional illustration in accordance with the invention; 
         FIG. 2  shows a side elevation of a first exemplary embodiment a contact pin in accordance with the invention; and 
         FIG. 3  shows a side elevation of a second exemplary embodiment of a contact pin in accordance with the invention. 
     
    
    
     DETAILED DESCRIPTION OF THE EXEMPLARY EMBODIMENT 
       FIG. 1  shows an exemplary embodiment of an electric machine in accordance with the invention in a sectional illustration. 
     An open-loop or closed-loop control unit formed as an electronic regulator  5  has a support plate  3  which, entirely encapsulated in a thermally conductive potting compound  2  made of polyurethane, is arranged in a first housing  8 , which is made from polyamide reinforced with glass fibers. 
     Provided on the support plate  3  are a first equipment element  11 , which is formed as a pressure sensor, and a second equipment element  12 , a third equipment element  13  and a fourth equipment element  15 , which are encased by the potting compound  2 . The first equipment element  11  is arranged on an underside  15  of the support plate  3 , and the second equipment element  12 , the third equipment element  13  and the fourth equipment element  14  are arranged on a top side  16  of the support plate  3 . The support plate  3  is thus equipped on both sides. 
     The first housing  8  and the support plate  3  are formed in a cylindrical manner. The first housing  8  is terminated at its end via an inserted plate  10 . The plate  10  is clamped in place by the first housing  8 . 
     The potting compound  2  completely fills a housing interior formed by the first housing  8  and the plate  10 . The polyurethane of the potting compound  2  has a Shore A hardness in the range between 48 and 53, a thermal conductivity of 0.97 W/mK and a glass transition temperature of about −60° C. The electric machine can therefore be used in a wide temperature range. 
     The potting compound  2  being made of polyurethane represents a favorable solution. In accordance with the invention, it is also conceivable, however, to make the potting compound  2  from silicone with a Shore A hardness in the range between 45 and 55, this resulting in comparable properties being achieved in comparison to when the potting compound  2  is made of polyurethane. 
     In the region of the top side  16  of the support plate  3 , a first contact pin  6  in the form of a first silver contact pin is connected to the support plate  3  and projects out of the first housing  8 . The support plate  3  is connected to a power supply (not illustrated) via this first contact pin  6 , and further contact pins that are not visible in  FIG. 1 , likewise formed as silver contact pins, are connected to the support plate  3  in the region of the top side  16 , and project out of the first housing  8 . 
     In the region of the underside  15  of the support plate  3 , a second contact pin  7  embodied as a second silver contact pin, and further contact pins that are not visible in  FIG. 1  and are in the form of further silver contact pins are connected to the support plate  3 . 
     Via the second contact pin  7  and the further contact pins arranged in the region of the underside  15  of the support plate  3 , the regulator  5  is connected to a motor  17  of a fluidic actuator  1  in the form of a hydraulic actuator. 
     The regulator  5  is connected to the actuator via a clamped connection. In accordance with the invention, it is also conceivable, however, to provide screw connections between the regulator  5  and the actuator  1 . 
     The first contact pin  6 , the second contact pin  7  and the further contact pins are partially encased by the potting compound  2 . 
     Provided between the second contact pin  7  and the motor  17  is a first cable run  18 , and further cable runs that are not visible are provided between the further contacts arranged in the region of the underside  15  of the support plate  3 . The first cable run  18  and the further cable runs are arranged within the actuator  1 , in a ring part  19  of the actuator  1 . Cables extending between the regulator  5  and the actuator  1  are not necessary. The actuator  1 , or the ring part  19  thereof, is attached to the open-loop or closed-loop control unit in a flush manner or terminates flush with the first housing  8 . 
     The motor  17  is formed as a brushless DC electric motor with an annular stator  20  and a rotor  21 . The stator  20  is provided in the ring part  19  of the actuator  1 . Via the stator  20 , or the connection thereof to the regulator  5 , the rotor  21 , which is mounted in the actuator  1  so as to be rotatable but not movable in translation, is driven. Rotary movements of the rotor  21  are transmitted to a spindle-like portion of the piston rod  22 , with the result that the piston rod  22  and a piston  23  connected thereto execute movements in translation in the direction of a longitudinal axis  24 . 
     The piston rod  22  and the piston  23  are provided in a cylinder  25  of the actuator  1 , which is encased by the ring part  19 . The piston rod  22  is mounted and guided in the cylinder  25  via a bearing (not shown), such that it can perform rotational and translational movements. Provided between the piston rod  22  and the cylinder  25  is a first seal, which is likewise not illustrated, for preventing moisture and particles etc. from penetrating into the cylinder  25 . 
     A chamber  4 , which is formed by the movable piston  23  and the cylinder  25 , is filled with a hydraulic fluid. The cylinder  25  therefore acts as a second housing  9  with regard to this hydraulic fluid. The chamber  4 , or the second housing  9 , directly borders the plate  10  of the regulator  5 . The open-loop or closed-loop control unit comes into contact with the chamber  4  in the region of the potting compound  2 . As a result, heat that is transmitted into the potting compound  2  by the support plate  3 , or the first equipment element  11 , the second equipment element  12 , the third equipment element  13  and/or the fourth equipment element  14 , is dissipated by the potting compound  2 , via the plate  10 , into the chamber  4 , i.e., to the hydraulic fluid. 
     In accordance with the invention, it is also possible to dispense with the plate  10 , with the result that the potting compound  2  directly adjoins the chamber  4 . The chamber  4  is connected via a first hydraulic line  26  to a hydraulic container (not shown), i.e., supplied with hydraulic fluid via this hydraulic container. 
     Via a second hydraulic line  27 , the chamber  4  is connected to a hydraulic telescopic shock absorber (likewise not illustrated) of a motor vehicle. With the piston  23 , or a pressure of the hydraulic fluid, a damping action of the telescopic shock absorber is set. To this end, the pressure in the chamber  4  is measured continuously via the pressure sensor or the first equipment element  11 , the measurement probe of which projects into the chamber  4 . 
     Provided between the first equipment element  11  and the cylinder  25  is a second seal (not illustrated) for preventing the potting compound  2  from being wetted with hydraulic fluid. With the regulator  5 , the measured pressure is compared continuously with a defined setpoint pressure. Based on a difference between the measured pressure and the setpoint pressure, the motor  17  is regulated by the regulator  5  via corresponding voltage stipulations at the stator  20 , i.e., the motor  17  is switched on or off or a speed of the rotor  21  is set, in order to reach or maintain the setpoint pressure in the hydraulic fluid or in the telescopic shock absorber via corresponding piston settings and movements. 
     The actuator  1  being formed as a hydraulic actuator represents a favorable solution. In accordance with the invention, it is also conceivable, however, for the actuator  1  to be formed, for example, as a pneumatic actuator and for this pneumatic actuator to be used for setting brake cylinder pressures in a truck brake of a rail vehicle. 
     Furthermore, it is conceivable for the open-loop or closed-loop control unit not be used as a regulator  5  but as a control unit, i.e., without a variable to be controlled being measured via a sensor or without this variable having a retroactive effect on a manipulated variable. For example, the control unit can be used in a hydraulic clamping device. In this connection, it is also conceivable for the open-loop or closed-loop control unit to be formed as an electronic control unit (ECU). 
     The second contact pin  7  is connected to the support plate  3  via a first component longitudinal portion  28 , shown in  FIG. 2  and  FIG. 3 , and to the ring part  19  of the actuator  1 , i.e., to a component, other than the support plate  3 , of the electric machine, via a third component longitudinal portion  30 , illustrated in  FIG. 2  and  FIG. 3 , that directly adjoins a second component longitudinal portion, likewise visible in  FIG. 2  and  FIG. 3 . The first component longitudinal portion  28  has a greater level of rigidity than the second component longitudinal portion  29 . In accordance with the invention, it is also conceivable for the second component longitudinal portion  29  to be connected to the ring part  19 . 
       FIG. 2  illustrates a first exemplary embodiment of a contact pin in accordance with the invention, which is also shown in  FIG. 1  (as second contact pin  7 ). This contact pin has a first component longitudinal portion  28 , a second component longitudinal portion  29  and a third component longitudinal portion  30 , which are oriented in the direction of a longitudinal axis  31 . 
     The first component longitudinal portion  28  has a greater level of rigidity than the second component longitudinal portion  29 . This greater rigidity is flexural rigidity and at the same time torsional rigidity. The fact that the second component longitudinal portion  29  is formed in a manner narrowing in the direction of the longitudinal axis  31 , or of its longitudinal axis  31 , and is also formed in a manner so as to bend in multiple opposite directions, contributes to an advantageous elastic component behavior or rigidity behavior. A first bend  34  and further bends are provided, which are each configured in a manner curved through 90° or 180° with respect to a vertical axis  32 , appearing in a projecting manner in  FIG. 2 , of the second component longitudinal portion  29 . 
     Furthermore, in order to improve the elastic properties of the contact pin, a first recess  35  and further recesses, i.e., a plurality of recesses, are provided in the second component longitudinal portion  29  in the direction of the vertical axis  32  thereof. 
     Furthermore, the second component longitudinal axis  29  is formed in a manner so as to include a multiple of slots, i.e., a first slot  36  and further slots are provided in the direction of a transverse axis  33  of the second component longitudinal portion  29 . 
     The first component longitudinal portion  28  directly adjoins the second component longitudinal portion  29  and is formed as a plug, which has been pressed into a support plate  3  shown in  FIG. 1 . 
     The third component longitudinal portion  30  directly adjoins the second component longitudinal portion  29 , is partially formed as a cuboid and has partially beveled edges. Via the third component longitudinal portion  30 , the contact pin is connected to a ring part  19 , illustrated in  FIG. 1 , of an actuator  1 . 
       FIG. 3  shows a second exemplary embodiment of a contact pin in accordance with the invention. This contact pin is formed in a similar manner to that of the first exemplary embodiment of the contact pin in accordance with the invention that is illustrated in  FIG. 2 . Therefore, largely identical reference signs to those in  FIG. 2  are used in  FIG. 3 . 
     In contrast to  FIG. 2 , however, a second component longitudinal portion  29  of the contact pin does not have pronounced curves or bends on its outer sides. This brings about simpler manufacture. 
     Thus, while there have been shown, described and pointed out fundamental novel features of the invention as applied to a preferred embodiment thereof, it will be understood that various omissions and substitutions and changes in the form and details of the devices illustrated, and in their operation, may be made by those skilled in the art without departing from the spirit of the invention. For example, it is expressly intended that all combinations of those elements which perform substantially the same function in substantially the same way to achieve the same results are within the scope of the invention. Moreover, it should be recognized that structures and/or elements shown and/or described in connection with any disclosed form or embodiment of the invention may be incorporated in any other disclosed or described or suggested form or embodiment as a general matter of design choice. It is the intention, therefore, to be limited only as indicated by the scope of the claims appended hereto.