Abstract:
The present disclosure describe a valve comprising a control unit for controlling a valve element, an electromagnet, and a valve element. The control unit may include an armature group. The electromagnet may include a coil and a pole core. The armature group may include a magnet armature moved by the electromagnet, an intermediate element, and a control pin for controlling the valve element. The control pin may be connected to the magnet armature via the intermediate element and moved together with the magnet armature. The intermediate element may be resilient and couple the control pin resiliently to the magnet armature.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application is a U.S. National Stage Application of International Application No. PCT/EP2014/072091 filed Oct. 15, 2014, which designates the United States of America, and claims priority to DE Application No. 10 2013 220 877.4 filed Oct. 15, 2013, the contents of which are hereby incorporated by reference in their entirety. 
     
    
     TECHNICAL FIELD 
       [0002]    The present disclosure relates to a valve and, in particular, a pressure control valve for a pressure circuit and, as one example, an accumulator injection system for internal combustion engines of motor vehicles. 
       BACKGROUND 
       [0003]    Known pressure control valves may have a switching magnet which opens and/or closes a valve element. Noise and mechanical wear can occur as a result of the mechanical pulses of the switching magnet in customary valves. In order to avoid the noise, a reduction in the mass of the moving components or a reduction in the magnetic forces are preferred. In addition, hardened materials are used in order to avoid wear. 
       SUMMARY 
       [0004]    In the present disclosure, a valve is taught which may have a reduced noise development and/or lower wear. 
         [0005]    According to some embodiments, a valve has a control unit for controlling a valve element. The control unit has an electromagnet and an armature group. In particular, the valve may be a solenoid valve, in which the electromagnet, together with the armature group of the control unit, can bring about opening and/or closing of the valve element which can have, for example, a valve needle or valve flap. 
         [0006]    According to some embodiments, the electromagnet has a coil and a pole core, it being possible for the coil to surround the pole core. The armature group has a magnet armature which can be moved by means of the electromagnet. Furthermore, the armature group has an intermediate element and a control pin for controlling the valve element. The control pin is connected to the magnet armature via the intermediate element and can be moved together with the magnet armature, the intermediate element being of resilient configuration and coupling resiliently in the control pin to the magnet armature. 
         [0007]    In some embodiments, the armature group, having the magnet armature, the intermediate element and the control pin, can be attracted to the pole core by way of the magnetic force in the case of energization of the coil. Here, the pole core serves as a stop for the magnet armature, which stop limits the movement of the magnet armature and therefore of the armature group in the direction of the pole core. If the magnet armature were directly connected rigidly to the control pin or if the intermediate element were of rigid configuration, the entire armature group would contribute to the pulse when the armature group comes into contact with the pole core. By virtue of the fact that the intermediate element is of resilient configuration, the effective mass of the elements of the armature group which come into contact with the pole core in the case of energization of the coil is reduced, because part of the pulse can be absorbed by way of the intermediate element of resilient configuration. 
         [0008]    According to some embodiments, the control unit has a spring which attempts to press the magnet armature and the pole core apart from one another. In particular, the spring can be arranged in an opening of the armature and can be arranged between the magnet armature and the pole core in such a way that the spring presses against the intermediate element and against the pole core. If the energization of the coil is switched off, the spring presses the armature group in a direction away from the pole core. In order to limit the movement of the armature group in the direction away from the pole core, the control pin can have a stop region which is pressed against a stop in a switched off state of the electromagnet. In some embodiments, the stop region can be configured as a collar-shaped part region of the control pin which faces away from the magnet armature. As has already been described above in conjunction with the switched on state of the electromagnet, in the case where the control pin and the magnet armature are directly connected rigidly to one another or where the intermediate element is of rigid configuration, all elements of the armature group would contribute to the pulse which is exerted on the stop. Part of the pulse can be absorbed by way of the intermediate element as a result of the intermediate element described here which is of resilient configuration, with the result that the pulse between the control pin and the stop can be reduced. 
         [0009]    As a result of the intermediate element of resilient configuration and its property of reducing pulses between the magnet armature and the pole core and between the control pin and the stop, the noise generation and the wear in the control unit can be reduced, in particular, at the stop and at the pole core and at the control pin. 
         [0010]    According to some embodiments, the intermediate element has a disk shape. There can be a central opening in the center of the disk-shaped intermediate element, through which opening the control pin protrudes and in which opening the control pin is fastened. The edge of the disk-shaped intermediate element can be fastened at least in regions to the magnet armature. Furthermore, the intermediate element can have cutouts. As a result of the arrangement of cutouts, webs or arms can be configured between the cutouts in the intermediate element, which webs or arms can form levers, by way of which the resilient action of the intermediate element can be influenced in a targeted manner. The intermediate element can be made from a resilient steel or can have a resilient steel of this type. Here, steel types are generally possible which make the elastic deformation possible, for example spring steel. 
         [0011]    According to some embodiments, the control pin has a noise-damping and/or wear-resistant material. For example, the control pin can have a rubber coating at least in the region of the collar-shaped part region which is pressed against the stop in the switched off state of the electromagnet. Furthermore, it is also possible that the control pin has carbon fibers at least partially or else over its entire length, which carbon fibers have particularly advantageous noise-damping and wear-resistant properties. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0012]    Further advantages, advantageous embodiments and developments result from the exemplary embodiments which are described in the following text in conjunction with the figures, in which: 
           [0013]      FIG. 1  shows a diagrammatic sectional illustration of a detail of a valve according to one exemplary embodiment, and 
           [0014]      FIGS. 2A and 2B  show diagrammatic illustrations of intermediate elements according to further exemplary embodiments. 
       
    
    
     DETAILED DESCRIPTION 
       [0015]    In the exemplary embodiments and figures, identical, similar or identically acting elements can be provided in each case with the same designations. The elements which are shown and their proportions to one another are not to be considered to be true to scale; rather, individual elements, such as layers, components, structural elements and regions, can be shown on an exaggeratedly large scale for improved visualization and/or for improved understanding. 
         [0016]      FIG. 1  shows a detail of a valve  100  which is configured as a solenoid valve and can be, for example, a pressure control valve for controlling a pressure of a fluid in a pressure circuit. For example, the valve  100  can be used for an accumulator injection system for internal combustion engines. 
         [0017]    The valve  100  has a control unit  10  and a valve element  20 . The valve element  20  which is shown only in details can have, for example, a valve needle or a valve flap which can be controlled by way of a control pin. Valve elements of this type are known to a person skilled in the art and will not be described further here. Furthermore, electrical connectors and plugs for electric contacting and actuation of the valve  100  are also not shown. 
         [0018]    The control unit  10  of the valve  100  has an electromagnet  1  and an armature group  2 . The control unit  10  is therefore configured as an electromagnetic actuator unit. The electromagnet  1  has a coil  11 , in particular a magnet coil, which is arranged in a housing  5 . Furthermore, the electromagnet  1  has a pole core  12 . 
         [0019]    The armature group  2  has a magnet armature  21  which, together with the pole core  12 , is arranged in a cup-shaped housing  6 . There is an air gap between the pole core  12  and the magnet armature  21  in the switched off state of the coil  11 . The housing  5  with the coil  11  is pushed over the cup-shaped housing  6  in a direction along the longitudinal axis L which is indicated using dashed lines. The coil  11 , the housing  5 , and the cup-shaped housing  6  with the pole core  12  and the magnet armature  21  together form an electromagnetic circuit. The latter attempts to reduce the air gap between the pole core  12  and the magnet armature  21  in the case of energization of the coil  11 , with the result that the magnet armature  21  is pulled against the pole core  12 . 
         [0020]    Furthermore, the armature group  2  has an intermediate element  22  which is connected to the magnet armature  21 . Furthermore, the intermediate element  22  is connected to a control pin  23  which protrudes into the valve element  20 . For example, the control pin is connected to a valve needle or valve flap of the valve element  20  in such a way that the valve element  20  can be controlled, that is to say opened and closed, by way of the control pin  23 . The control pin  23  is coupled to the magnet armature  21  by way of the intermediate element  22  and can thus be moved together with the magnet armature  21 . The intermediate element  22  is of resilient configuration and therefore couples the control pin  23  resiliently to the magnet armature  21 . To this end, the resilient intermediate element  22  has, in particular, a resilient steel which is capable of being deformed elastically. For example, the intermediate element  22  can be made from spring steel. 
         [0021]    Furthermore, the control unit  10  has a spring  3  which attempts to press the magnet armature  21  and the pole core  12  apart from one another. In particular, the spring  3  acts counter to the movement of the magnet armature  21  in the case of energization of the coil  11 . If the energization of the coil  11  is switched off, the spring  3  presses the magnet armature along the longitudinal axis L away from the pole core  12 . 
         [0022]    The magnet armature  21  has, in particular, an armature opening  211 , through which the control pin  23  protrudes at least partially. Furthermore, the spring  3  is also arranged in the armature opening  211  and presses against the pole core  12  and the intermediate element  22 . 
         [0023]    The intermediate element  22  is of disk-shaped configuration and has a central opening, through which the control pin  23  protrudes. In the region of the central opening, the control pin  23  is connected, for example welded, to the intermediate element  22 . Furthermore, the intermediate element  22  is connected, for example welded, to the magnet armature  21  at an edge region. In particular, the intermediate element  22  can be connected to the magnet armature  21  in a punctiform manner in edge regions or else in an entire circumferential edge region. 
         [0024]    The control pin  23  has a stop region in the form of a collar-shaped part region  231  which faces away from the magnet armature  21  and, in a switched off state of the electromagnet  1 , is pressed against a stop  4  by way of the action of the spring  3 . The stop  4  is formed by way of a part of the valve element  20 , into which the control pin  23  protrudes. For example, the stop  4  can be formed by way of a part of a valve housing, into which the control pin protrudes through an opening. In this case, the collar-shaped part region  231  can be formed by way of a step-shaped cross-sectional change of the control pin  23 , whereas the stop  4  is formed by way of the edge which delimits the opening, through which the control pin  23  protrudes. 
         [0025]    In order to open and close the valve  100 , the coil  11  is energized and the energization is switched off, respectively. In the case of energization of the coil  11 , the armature group  2  is attracted toward the pole core  12  by way of the magnetic force counter to the spring  3 , as described above, whereas, in the case of switched off energization, the spring  3  presses the armature group  2  against the stop  4 . The respective pulse, with which the magnet armature  21  comes into contact with the pole core  12  or the collar-shaped part region  231  of the control pin  23  comes into contact with the stop  4 , can be reduced in the case of the valve  100  by way of the intermediate element  22  of resilient configuration, since the intermediate element  22  of resilient configuration can in each case absorb a part of the pulse by way of an elastic deformation in the case of both movements. As a result, both noise development and wear at the pole core  12  and at the magnet armature  21  and at the control pin  23  and at the stop  4  can be reduced in comparison with rigid fastening of the control pin  23  to the magnet armature  21 . 
         [0026]    Furthermore, if the control pin  23  has a noise-damping and/or wear-resistant material, for example carbon fibers or a rubber coating between the pin  23  and the stop  4 , the valve may have reduced noise development and/or wear. 
         [0027]      FIGS. 2A and 2B  show exemplary embodiments for the resilient intermediate element  22 . In particular, the intermediate element  22  has a disk-shaped configuration. The control pin  23  protrudes through a central opening  221 , as shown in  FIG. 1 , and is connected in the region of the central opening  221  to the intermediate element  22 , for example by way of welding. The edge region of the intermediate element  22  is connected to the magnet armature  21 , as shown in  FIG. 1 , for example likewise by way of welding. 
         [0028]    As shown in  FIG. 2A , the intermediate element  22  has, furthermore, cutouts  222  which are arranged around the central opening  221  and therefore around the control pin  23 . The cutouts  222  result in geometries with webs or arms which form levers which can be deformed elastically. As a result, the resilient action of the intermediate element  23  can be influenced in a targeted manner. 
         [0029]    The intermediate element  22  according to the embodiment of  FIG. 2B  has cutouts which extend in each case as far as the edge region of the intermediate element  22 , with the result that spiral arms are formed which are separated from one another by way of the cutouts  222 . In comparison with the embodiment of  FIG. 2A , said spiral arms form longer levers which can be deformed elastically, as a result of which the above-described reduction in the pulses between the magnet armature  21  and the pole core  12  and between the control pin  23  and the stop  4  can be reinforced. In particular, the resilient properties of the intermediate element  23  can be influenced in a targeted manner by way of the material, the material thickness, the size of the cutouts and the position of the cutouts. For example, depending on the spring property in the embodiments which are shown, the intermediate element  22  can have a thickness of greater than or equal to 0.1 mm and less than or equal to 3 mm or even more than 3 mm. 
         [0030]    The invention is not restricted by the description using the exemplary embodiments to the latter. Rather, the invention comprises every novel feature and every combination of features, which includes, in particular, every combination of features in the patent claims, even if said feature or said combination itself is not specified explicitly in the patent claims or exemplary embodiments.