Solenoid valve

Abstract

Solenoid valve (1) with a valve body (60) and a valve seat (53), wherein the valve body (60) is movable along a travel axis (A) between a closed position and an open position, the valve seat (53) is designed as a cylindrical seat component (50), with a first media channel (51) in the form of a bore, which is centrally located in the seat component (50) and terminates at its end face with an opening region (54), with second media channels (52) which are arranged substantially axially and radially adjacent to the first media channel (51) in the seat component (50), the valve body (60) in the closed position bears against the valve seat (53) with a seat body (62) and closes the opening region (54) of the first media channel (51) and is lifted from the valve seat (53) upon movement into the open position and releases the opening region (54), the seat component (50) a deflection chamber (55) for the medium,which extends axially between an end-face deflecting wall (56) and the opening area (54) of the first media channel (51) and encompasses the second media channels (52) in a radial direction, the deflecting wall (56) having a through-bore (57) for a closing plunger (61) of the valve body (60), and the closing plunger (61) extending axially through the through-bore (57) into the deflecting chamber (55), the closing plunger (61) carrying the seat body (62) at its end, and when the seat body (62) lifts off the valve seat (53), an annular gap forms between the seat body (62) and the valve seat (53), whereby medium exiting from the first media channel (51) at least partially impacts the deflecting wall (56) and is deflected towards the second media channels (52), or medium exiting from the second media channels (52) at least partially impacts the deflection wall (56) hits and is deflected in the direction of the first media channel (51),characterized in that the deflecting wall (56) is designed as a feedthrough disk (58) which is inserted into the end face of the seat component (50) or axially attached to the seat component (50), and the opening area (54) is designed as a seat baffle (59) which is inserted into the seat component (50), wherein the feedthrough disk (58) and the seat baffle (59) are designed as separate components, wherein the second media channels (52) are inclined exclusively radially to the axis of travel (A), penetrate a circumferential wall of the deflecting chamber (55) in the seat component (50) and are located on one of the feedthrough disks (58) opposite the

Description

The invention relates to a solenoid valve according to the preamble of claim 1, as is known from DE 10 2009 060 293 A1.Such solenoid valves comprise a valve body and a valve seat. The valve body is movable along a travel axis between a closed position and an open position.The valve seat is designed as a cylindrical component. A first medium channel in the form of a bore is mounted centrally in the seat component and closes off at the end with an orifice region. Second media channels are arranged in the seat component so as to extend substantially axially and radially adjacent to the first media channel.In the closed position, the valve body abuts with a seat body against the valve seat and closes the opening region of the first media channel. In the open position, the valve body is lifted from the valve seat and thereby releases the opening region of the first medium channel.Solenoid valves are used for a wide variety of tasks in hydraulics.Examples of solenoid valves are known from DE 10 2009 055 118 A1, DE 10 2009 060 294 A1, DE 10 2012 019 193 A1, U.S. Pat. No. 5,271,599 A or U.S. Pat. No. 5,002,253 A.Solenoid valves from the prior art frequently consist of two separate assemblies, namely the valve assembly that enables the valve function and the electromechanical actuator that actuates the valve assembly. The valve assembly and the actuator are cascaded in an axial row to form the complete solenoid valve.From the previously filed but post-published German patent application DE 10 2022 108 928 A1, a highly integrated quick-action switching valve is known, in which the valve body is largely integrated in the actuator. Compared to the cascaded arrangement described above, it is possible to realize a solenoid valve of an extremely compact design.Although such solenoid valves have proven themselves in practice, there is a further need for optimization. For example, it has proved to be problematic to achieve sufficient accuracy for the power adjustment in digital hydraulic pump controllers. With small nominal volume flows, it is often not possible to realize the required dynamics, as is possible when used in conjunction with purely mechanical regulations. The valves currently used are usually pressure-balanced, thus do not allow an integrated DBV function. Previous approaches to solutions aim at increasing the restoring force of the closing element by increasing the spring prestress and the spring stiffness. However, the increase in the spring force worsens the opening dynamics; the actuator force must also be increased, which ultimately leads to an increase in the installation space.The key to solving these problems lies in the recognition that the medium experiences a deflection of approximately 180° as a result of the arrangement of the medium channels and thereby exerts a force on the closing element, which force acts against the spring and thus opens, for example in the case of the normally closed valve described at the beginning.DE 10 2009 060 293 A1 is now based on the concept of absorbing the force generated as a result of the flow deflection largely within the valve seat.This is achieved in concrete terms in that the seat component of the valve seat has a deflection chamber for the medium. The deflecting chamber extends in the axial direction between an end-face deflecting wall and the orifice region of the first media channel. In the radial direction, it engages the second media channels. The deflecting wall has a passage bore for a closing plunger of the valve body, wherein the closing plunger passes axially through the passage bore and dips into the deflecting chamber. The closing plunger carries at its end the seat body which closes the opening region of the first media channel.When the seat body lifts from the valve seat, an annular gap is formed between the seat body and the valve seat, through which the medium passes. The medium emerging from the first medium channel impinges at least partially on the deflecting wall and is deflected from there in the direction of the second medium channels. When flowing in the opposite direction, i.e. when the medium exits the second medium channels, it is deflected in the direction of the first medium channel when it impinges on the deflecting wall.This ensures that the force resulting from the deflection is largely absorbed directly by a deflection wall or by the seat component itself. With the exception of the seat body, neither the valve body nor the armature are acted upon by the medium flow to any appreciable extent. As a result, the effect of the flow on the closing force of the spring can be largely neutralized.Nevertheless, there is a further need for optimization, in particular with regard to cost-effective production.According to the invention, the deflecting wall is designed as a lead-through disc which is inserted into the seat component at the end face or is attached axially to the seat component. This enables a constructionally simple implementation of the deflection chamber in that the valve seat has a correspondingly suitably dimensioned bore at the end facing the armature, which bore is closed off on the front side by the feed-through disc.Between the passage bore and the closing plunger, a radial annular gap can be provided, which allows a part of the medium to pass through in a generally known manner in order to realize a pressure compensation.Likewise, according to the invention, the mouth region of the seat component is designed as a seat diaphragm which is inserted into the seat component. This results in production-related advantages. Thus, the valve volume can be scaled in a simple manner by a correspondingly adapted seat diaphragm.The seat body can have the shape of a ball, a ball segment, a cone or a truncated cone, whereby the flow through the annular gap that is established can be adjusted in a targeted manner in the open position of the valve.A particularly compact construction can be realized in that the valve body is integrated in the interior of an armature designed as a hollow cylinder. This radially nested construction provides a highly integrated solenoid valve which can be made extremely compact and at the same time has a finely controllable response behavior.For actuation, the solenoid valve can comprise an armature and a pole tube. The armature is mounted axially displaceably, for example, in the pole tube between a first and a second end position. The armature assumes the first end position in the current-free state. When current is supplied, it is displaced in the direction of the second end position, as a result of which the valve body moves from the closed position in the direction of the open position.Frequently, such solenoid valves are designed as so-called "normally closed" valves, in which the orifice region of the first medium channel is kept closed in the non-energized state. For this purpose, the valve body is forced into the closed position by a spring.This radially nested construction creates a highly integrated solenoid valve which can be made much more compact than the solenoid valves from the prior art. The actuator thus has largely integrated the valve body, as a result of which the overall height of the solenoid valve and also the moved mass can be significantly reduced without adversely affecting the magnetic force and, associated therewith, the switching characteristic.The invention is described in more detail below with reference to an exemplary embodiment. The following are shown: FIG. 1 shows a solenoid valve not belonging to the invention in axial section, FIG. 2 shows an enlarged detail view of the solenoid valve not belonging to the invention in the region of the valve body and its surroundings in axial half section, FIG. 3 shows a solenoid valve according to the invention.FIG. 1 shows a solenoid valve 1, which is designed as a normally closed 2 / 2-way seat valve with a pressure limiting function.The solenoid valve 1 has a pole tube 10 which passes completely through the solenoid valve 1 in the axial direction and carries not only the actuator system required for the actuation, but also the components relevant to the valve function. The pole tube 10 has an amagnetic part 11 which ensures magnetic decoupling.A coil 40 is accommodated in a coil housing 20 which is pushed and supported radially on the outside with respect to the pole tube 10. In the axial direction, the coil housing 20 is secured by a securing element 30 in the form of a nut which is in engagement with a threaded section 13 mounted in the upper section of the pole tube 10.At the opposite end, a receiving bore 15 is provided in the pole tube 10, in which bore an armature 80 is mounted so as to be axially displaceable along a displacement axis A. The receiving bore 15 also receives a valve seat 53 in the form of a cylindrical seat component 50, which is screwed to the pole tube 10 via a threaded section 18.The seat component 50 has, as a medium connection channel, a first channel 51 in the form of a bore which passes centrally through the seat component 50 axially and merges at the end face into an orifice region 54. Furthermore, second channels 52 are present, which form a further medium channel, and are arranged in the seat component 50 so as to extend axially and radially adjacent to the first channel 51.The armature 80 is of hollow cylindrical configuration and accommodates a valve body 60 in an axially displaceable manner. The valve body 60 has a closing plunger 61 which carries on the end face a seat body 62 which is directed towards the opening region 54 of the valve seat 53.The valve body 60 is biased by a spring 70 toward the valve seat 53. For this purpose, the spring 70 is accommodated in the pole tube 10 in a receiving bore 17 and is axially supported.In the seat component 50, a deflection chamber 55 for the medium is formed. The deflection chamber 55 extends in the axial direction between an end-face deflection wall 56 and the opening region 54 of the first channel 51. In the radial direction, the deflection chamber 55 extends outward to such an extent that it engages the second channels 52. In the exemplary embodiment shown in FIG. 1, the deflecting wall 56 is formed integrally with the seat component 50.The deflecting wall 56 has a passage bore 57 through which the closing plunger 61 of the valve body 60 passes axially and which dips into the deflecting chamber 55 with the seat body 62 attached on the end face.The operating sequence during the opening and closing process is explained below with reference to FIGS. 1 and 2.The valve body 60 is in the closed position in the illustration according to FIGS. 1 and 2 a.For the opening process, the solenoid valve 1 is energized, whereupon the armature 80 moves upward and drives the valve body 60 upward against the action of the spring 70 and finally makes it bear against an axial section 16 of the pole tube 10 serving as stroke limitation. The position shown in FIG. 2 bis thus reached. Intermediate positions can be approached with a suitable control strategy of the magnet.The seat body 62 is now completely lifted from the valve seat 53 and the fluid can flow out of the first channel 51 from the orifice region 54 at this point and is radially deflected by the seat body 62. The fluid impinges on the deflecting wall 56 opposite one another, is deflected from there in the direction of the second channels 52 and can finally flow off from there.It is directly evident from the illustration according to FIG. 2 b that the forces generated by the flow medium as a result of the deflection are absorbed by the seat component 50 on the deflection wall 56. Only a small part of the flow forces acts on the valve body 60 and, associated therewith, on the spring 70, as a result of which the valve reliably closes largely independently of the forces generated by the deflection of the medium.The advantages described also result analogously in the case of a reverse flow direction, i.e. an inflow of the medium through the second channels 52 with the deflection at the deflection wall 56 and the outflow through the first channel 51.The valve body 60 is in the open position in the illustration according to FIG. 2 b. In order to close the solenoid valve 1 again, the current supply is switched off, as a result of which the valve body 60 is forced by the spring 70 in the direction of the valve seat 53. At the end of the closing process, the seat body strikes the valve seat 53 and thus closes the opening region 54 of the first channel 51.The embodiment according to FIG. 3 differs from that of FIG. 1 only in the structural configuration of the deflection chamber 55. the components and component sections shown in FIG. 3 are designated corresponding to the illustration according to FIG. 1 and also have the same meaning. In this respect, reference is made to the explanations relating to FIG. 1.The deviation in the exemplary embodiment according to FIG. 3 now specifically relates to the deflecting wall 56 being formed as a separate feed-through disc 58, which is inserted into the seat component 50 on the end face.On the opposite side, the opening region 54 is designed as a separate seat diaphragm 59 which is likewise inserted into the seat component 50.The design of the feed-through disc 58 and the seat diaphragm 59 as separate components has advantages due to production, on the one hand, with the possibility of valve scaling. In addition, by varying the geometry of the passage bore 57 in conjunction with the selection of the diameter of the closing plunger 61 on the one hand and the design of the valve seat 53 in conjunction with the seat body 62, a variation of the flow conditions can be achieved in a simple manner, so that, while maintaining the components, a broad spectrum of response characteristics of the solenoid valve can otherwise be implemented.Thus, it is not only possible to reduce the flow-induced forces acting against the spring 70, but also to neutralize these completely. It is also possible to generate reverse-acting flow forces to support the spring force. This is based on pressure differences in the deflection chamber 55 and the region around the armature 80 which press the valve body 60 in the direction of the valve seat 53. This allows for higher dynamics and more sensitive response. This targeted influencing is also referred to as "fluid force shaping".List of reference characters1 Solenoid valve 10 Pole tube 11 Amagnetic pole tube part 13 Threaded section 15 Receiving bore 16 Axial section 17 Receiving bore 18 Threaded section 20 Coil housing 30 Securing element 40 Coil 50 Seat component 51 First channel 52 Second channel 53 Valve seat 54 Opening region 55 Deflection chamber 56 Deflection wall 57 Passage bore 58 Passage disk 59 Seat diaphragm 60 Valve body 61 Closing plunger 62 Seat body 70 Spring 80 Armature A Displacement axis

Claims

Solenoid valve (1) having a valve body (60) and a valve seat (53), wherein the valve body (60) is displaceable along a displacement axis (A) between a closed position and an open position, the valve seat (53) is designed as a cylindrical seat component (50), having a first medium duct (51) in the form of a bore which is mounted centrally in the seat component (50) and terminates at the end side with an orifice region (54), having second medium ducts (52) which are arranged in the seat component (50) so as to extend substantially axially and radially adjacent to the first medium duct (51), the valve body (60), in the closed position, bears with a seat body (62) against the valve seat (53) and closes the orifice region (54) of the first medium duct (51) and, starting from a movement into the open position, is lifted from the valve seat (53) and releases the orifice region (54), the seat component (50) has a deflection chamber (55) for the medium, which extends in the axial direction between an end-face deflection wall (56) and the mouth region (54) of the first medium channel (51) and engages in the radial direction the second medium channels (52), the deflection wall (56) has a passage bore (57) for a closing plunger (61) of the valve body (60), and the closing plunger (61) dips axially through the passage bore (57) into the deflection chamber (55), the closing plunger (61) carries the seat body (62) at the end and an annular gap is established between the seat body (62) and the valve seat (53) when the seat body (62) is lifted off the valve seat (53), whereby medium emerging from the first media channel (51) impinges at least partially on the deflecting wall (56) and is deflected in the direction of the second media channels (52) or medium emerging from the second media channels (52) impinges at least partially on the deflecting wall (56) and is deflected in the direction of the first media channel (51), characterized in that the deflecting wall (56) is designed as a feed-through disc (58), which is inserted at the end face into the seat component (50) or is attached axially to the seat component (50), and the orifice region (54) is designed as a seat diaphragm (59), which is inserted into the seat component (50), wherein the feed-through disc (58) and the seat diaphragm (59) are designed as separate components, wherein the second media channels (52) are exclusively inclined radially with respect to the displacement axis (A), a circumferential wall of the deflection chamber (55) in the seat component (50) and opening out at a shoulder of the seat component (50) opposite the feed-through disc (58), wherein the second media channels (52) partially pass through the bottom wall of the deflection chamber (55) axially opposite the feed-through disc (58).Solenoid valve (1) according to Claim 1, characterized in that a radial annular gap is provided between the passage bore (57) and the closing plunger (61).Solenoid valve (1) according to Claim 1 or 2, characterized in that the seat body (62) has the shape of a ball, a segment of a ball, a cone or a truncated cone.Solenoid valve (1) according to one of Claims 1 to 3, characterized in that the valve body (60) is integrated in the interior of an armature (80) which is designed as a hollow cylinder.

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