EP3702589A1 - Steam expander and valve shaft guide for a steam expander - Google Patents

Steam expander and valve shaft guide for a steam expander Download PDF

Info

Publication number
EP3702589A1
EP3702589A1 EP20150411.5A EP20150411A EP3702589A1 EP 3702589 A1 EP3702589 A1 EP 3702589A1 EP 20150411 A EP20150411 A EP 20150411A EP 3702589 A1 EP3702589 A1 EP 3702589A1
Authority
EP
European Patent Office
Prior art keywords
valve
housing
valve stem
sliding bush
valve seat
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
EP20150411.5A
Other languages
German (de)
French (fr)
Other versions
EP3702589B1 (en
Inventor
Richard Langlechner
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Langlechner GmbH and Co KG
Original Assignee
Langlechner GmbH and Co KG
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Langlechner GmbH and Co KG filed Critical Langlechner GmbH and Co KG
Publication of EP3702589A1 publication Critical patent/EP3702589A1/en
Application granted granted Critical
Publication of EP3702589B1 publication Critical patent/EP3702589B1/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01L—CYCLICALLY OPERATING VALVES FOR MACHINES OR ENGINES
    • F01L3/00—Lift-valve, i.e. cut-off apparatus with closure members having at least a component of their opening and closing motion perpendicular to the closing faces; Parts or accessories thereof
    • F01L3/08—Valves guides; Sealing of valve stem, e.g. sealing by lubricant
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01B—MACHINES OR ENGINES, IN GENERAL OR OF POSITIVE-DISPLACEMENT TYPE, e.g. STEAM ENGINES
    • F01B29/00—Machines or engines with pertinent characteristics other than those provided for in preceding main groups
    • F01B29/08—Reciprocating-piston machines or engines not otherwise provided for
    • F01B29/10—Engines
    • F01B29/12—Steam engines
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01L—CYCLICALLY OPERATING VALVES FOR MACHINES OR ENGINES
    • F01L2303/00—Manufacturing of components used in valve arrangements
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01L—CYCLICALLY OPERATING VALVES FOR MACHINES OR ENGINES
    • F01L2820/00—Details on specific features characterising valve gear arrangements
    • F01L2820/01—Absolute values

Definitions

  • the present invention relates to a valve stem guide for a steam expander according to the preamble of claim 1, and to a steam expander with such a valve stem guide.
  • Valve stem guides of the generic type are used to guide the valve stem of an inlet valve or an outlet valve of a steam expander in piston engine design, also called steam engine.
  • a valve stem has an end region on the valve body side and an end region facing away from this, correspondingly remote from the valve body, between which the region of the valve stem guided by means of the valve stem guide extends as a rule.
  • the end region of the valve stem on the valve body side carries and / or actuates a valve body which, together with a valve seat of the valve, opens and closes an inlet or an outlet for the working medium steam of the steam expander so that it enters the cylinder chamber or out of the cylinder chamber in individual cycles of the steam expander can flow, depending on whether it is an inlet valve or an outlet valve.
  • the valve stem guide is often provided with or formed by a sliding bushing which is inserted into a housing, for example a crankcase, of the steam expander.
  • a housing for example a crankcase
  • the insertion takes place by producing a press fit, that is, the construction of a so-called interference fit between the sliding bush and the housing surrounding it in order to achieve a force-locking connection.
  • the housing is provided with an opening, in particular a bore, for the sliding bushing and the sliding bushing is strongly cooled before it is inserted, whereby the housing can be heated at the same time, so that the sliding bushing contracts and the opening in the housing in particular expands so that the sliding bush can be inserted into the opening. After a Temperature equalization between the sliding bush and the housing results in the desired press fit.
  • the present invention is based on the object of specifying a valve stem guide for a steam expander which avoids the problem of wear and leakage in the area of the valve seat insert.
  • the valve stem guide should be characterized by a particularly reliable operation of the corresponding valves with a long service life.
  • valve stem guide with the features of claim 1.
  • advantageous and particularly expedient embodiments and a steam expander according to the invention with such a valve stem guide are specified.
  • a valve stem guide according to the invention for a steam expander has a housing which is, for example, a component of the crankcase of the steam expander.
  • An opening running in the housing is provided for receiving a valve stem, the opening running in particular in the direction of a longitudinal axis of the housing.
  • a sliding bushing is inserted into the opening which has an inner guide surface for forming a sliding bearing for the valve stem.
  • the valve stem can slide with its outer surface directly on the inner guide surface of the sliding bush, whereby a material pairing is advantageously chosen at this interface or this sliding bearing that offers favorable lubricating properties.
  • the sliding bush is made of brass and the housing is made of steel.
  • the sliding bushing is screwed into the housing, either directly, that is, the sliding bushing and the housing each have a thread, the two threads being in engagement with one another, or indirectly, that is, the sliding bushing has a thread that is connected to a thread of a counter element cooperates, which in turn is locked in place in the housing.
  • the sliding bushing is only inserted into the valve seat ring, that is to say inserted free from a screw connection.
  • the sliding bushing is inserted loosely into the valve seat ring, that is to say with play between the sliding bushing and the valve seat ring.
  • the valve seat ring has, for example, a central bore which has a diameter that is greater than the outer diameter of the sliding bush, at least in the end facing the valve seat ring.
  • the diameter of the bore in the valve seat ring is at least 1/100 mm or 1/10 mm larger than the outer diameter of the sliding bush.
  • the sliding bushing By (loosely) inserting the sliding bushing into the valve seat ring, the sliding bushing is guided laterally, in particular over the full circumference of its end facing the valve seat ring, so that leverage forces previously acting on the sliding bushing are safely diverted without bending the sliding bushing.
  • the sliding bush in the region of the end facing the valve seat ring, the sliding bush is on the one hand enclosed by the material of the valve seat ring and on the other hand is enclosed by the material of the housing adjacent to the valve seat ring. Accordingly, there remains no free space radially outside the sliding bushing inside the housing.
  • the sliding bush has an external thread on an outer surface, by means of which the sliding bush is screwed into an internal thread provided in the opening.
  • the external thread on the sliding bush advantageously extends only over part of the axial length of the sliding bush. This is advantageous in order to reduce undesired introduction of force into the thread as a result of thermal expansions over the thread length.
  • the internal thread also extends in the housing only over part of the axial extent of the sliding bush or the axial section which the sliding bush faces in the opening.
  • the sliding bushing has a stop by means of which it strikes the housing when the sliding bushing is screwed into the housing or when the sliding bushing is screwed into the housing.
  • the stop can be designed, for example, in the form of a collar protruding in the radial direction on the sliding bush.
  • the stop strikes, for example, on the end face of a surface of the housing surrounding the opening.
  • the sliding bushing can have a driving profile at one axial end.
  • the driving profile can, for example, have the shape of an external hexagon.
  • other profiles are also possible, for example an internal drive such as hexagon socket or Torx (hexalobular socket).
  • Other external drives are also possible.
  • the driving profile is provided at the axial end of the sliding bushing, on which the external thread and in particular the stop is positioned.
  • the valve seat ring inserted coaxially to the sliding bushing in the housing preferably forms a valve seat for the inlet valve or outlet valve to which the valve stem is assigned.
  • the valve stem carries, for example, as shown at the beginning, at its axial end, which is advantageously more or less enclosed by the valve seat insert, a valve body which, together with the valve seat, more or less restricts the opening cross-section of the valve depending on the position of the valve body relative to the valve seat .
  • the opening in the housing can be designed to be stepped widened at its axial end facing the valve seat ring, so that the diameter of the opening expands in one step to a comparatively larger diameter that is adapted to the outer diameter of the valve seat ring.
  • the valve seat insert can be pressed into the opening in the housing, that is, an undersize fit is provided between the outer diameter of the valve seat insert and the inner diameter of the opening, in particular the widening in the opening.
  • valve stem guides in a steam expander are designed with sliding bushings inserted into the valve seat rings. Rather, only a part of the valve stem guides can be designed accordingly, whereas in another part of the valve stem guides an axial gap is provided between the valve seat ring and the sliding bush, namely in valve stem guides on which a lower leverage acts.
  • a steam expander has at least one cylinder or a plurality of cylinders, for example two cylinders, each one Have a cylinder space and a cylinder piston.
  • the cylinder piston is displaced by steam expansion in the cylinder space and can drive a crankshaft.
  • the or each cylinder space is connected to a steam supply of the steam expander via an inlet valve and to a steam outlet of the steam expander via an outlet valve.
  • At least one inlet valve which shuts off the steam supply after the cylinder space has been filled with steam, and / or an outlet valve, which blocks the steam discharge after the steam has been discharged from the cylinder space, has / have a valve seat, a valve body and one on the valve body for its movement relative to the valve seat connected valve stem, which is slidably mounted in a valve stem guide according to the invention.
  • FIG. 1 the area of an inlet valve 15 of a steam expander is shown.
  • the inlet valve 15 opens and closes the flow cross section for steam of a steam supply 18, via which the steam is passed into the cylinder space 19 of the steam expander.
  • the expanding steam moves the cylinder piston 20 along the cylinder liner 21 and thus drives a piston rod 22 that is not shown in detail here Crankshaft.
  • the cylinder liner 21 and the outer surface 23 of the cylinder piston 20 form a pairing that is optimized with regard to the sliding properties. However, this is not absolutely necessary; rather, the cylinder piston 20 could also slide directly on a surface of the housing 1.
  • a sliding bush 5 is also inserted, in which the valve stem 4 of the inlet valve 15 slides.
  • the sliding bush 5 has inserted sliding elements 24 which form a sliding bearing for the valve stem 4. Accordingly, the sliding elements 24 have a guide surface 6 for the valve stem 4.
  • the valve stem 4 could also slide directly in the base body of the sliding bush 5, so that the inner surface 25 would form the guide surface for the valve stem 4.
  • valve stem 4 carries the valve body 17, which cooperates with the valve seat 12 in order to adjust the flow cross-section in the steam supply 18 by varying the distance between the valve body 17 and the valve seat 12.
  • the valve seat 12 is formed here by a valve seat ring 11 which is inserted into the housing 1, but could also be implemented directly in the housing 1.
  • the sliding bush 5 is not extended up to the valve seat ring 11 and inserted into it, but a distance between the sliding bush 5 and the valve seat ring 11 is provided.
  • the other features shown here can, however, also be provided in a valve stem guide designed according to the invention.
  • a spring element 26 is provided, which here acts to close the inlet valve 15.
  • the inlet valve 15 can by applying a force by means of a not shown here Camshaft on the valve stem 4 against the force of the spring element 26, here in the form of a compression spring, are opened.
  • the sliding bush 5 has over a portion of the axial section of the outer surface 7 inserted into the opening 3 in the housing 1, here over significantly less than half the axial length of the inserted outer surface 7, an external thread 8 which is inserted into an internal thread 9 in the opening 3 is screwed in, in such a way that the sliding bush 5 strikes with the protruding collar 27 on an end face of the housing in the axial direction of the opening 3 and is braced. This also prevents the sliding bush 5 from slipping within the opening 3 if the housing 1 in the area of the opening 3 is heated more than the inserted sliding bush 5 due to its proximity to the cylinder chamber 19 and the steam supply 18 and is therefore subject to greater thermal expansion.
  • valve stem guides of the steam expander are shown, the two middle valve stem guides shown being designed according to the invention, whereas the two outer ones are different.
  • Corresponding elements are numbered with corresponding reference symbols.
  • FIG. 2 In the embodiment according to Figure 2 four openings 3 with inserted slide bushings 5 are provided, the two middle ones serving to guide the valve stem 4 each of an inlet valve 15 and the two outer ones to guide a valve stem 4 of outlet valves 16.
  • the sliding bushings 5 in turn have a collar 27 as a stop, for The respective sliding bush 5 is braced in the housing 1 when the sliding bush 5 is screwed with its external thread 8 into the internal thread 9 in the opening 3.
  • a driving profile 10 for example in the form of an external hexagon, is provided, which provides a drive for screwing the sliding bush 5 into the housing 1.
  • valve seat ring 11 which forms a valve seat 12, is inserted into the opening 3 in addition to the sliding bush 5.
  • the shape largely corresponds to that of the valve seat ring 11 according to FIG Figure 1 .
  • the valve stem guide has an axial gap 14 between the slide bushings 5 and the valve seat rings 11.
  • the two inner valve seat rings 11, on the other hand, have a significantly larger axial extent (extent in the direction of the longitudinal axis 2) and, in contrast to the outer valve seat rings 11, do not end flush with the housing 1, but protrude from it and protrude into an attached cover .
  • the two outer sliding bushings 5 are only enclosed by the housing 1 in the circumferential direction.
  • the two inner sliding bushings 5, however, extend into the respective valve seat ring 11 and are inserted into it.
  • the respective valve seat ring 11 thus effects a radial guidance of the sliding bush 5 and prevents it from bending.
  • the sliding bush 5 is "freely" inserted into the valve seat ring 11, without a screw connection or an undercut, so that different thermal expansions of the sliding bush 5 and the valve seat ring 11 or the housing 1 are not hindered and the sliding bush 5 moves in the direction of the longitudinal axis 2 Valve seat ring 11 can move.
  • crankshaft 28 is also shown, which is driven by the cylinder piston, not shown here, via the piston rods.
  • camshaft 29 is also shown, the cams of which (not in Individually but only partially shown) actuate the valve stems 4 against the force of the spring elements 26.
  • the spring elements 26 are supported outside the collar 27 at the end of the housing 1, enclosing it.

Abstract

Die Erfindung betrifft eine Ventilschaftführung für einen Dampfexpander- mit einem Gehäuse;mit wenigstens einer im Gehäuse verlaufenden Öffnung zur Aufnahme eines Ventilschafts; wobei- in die Öffnung eine Gleitbuchse eingesetzt ist, die eine innere Führungsoberfläche zur Ausbildung eines Gleitlagers für den Ventilschaft aufweist;- die Gleitbuchse unmittelbar oder mittelbar in das Gehäuse eingeschraubt ist; wobei- koaxial zur Gleitbuchse ein Ventilsitzring in die Öffnung im Gehäuse eingesetzt ist.Die erfindungsgemäße Ventilschaftführung dadurch gekennzeichnet, dass die Gleitbuchse in den Ventilsitzring nur eingesteckt ist.The invention relates to a valve stem guide for a steam expander with a housing, with at least one opening running in the housing for receiving a valve stem; wherein - a sliding bush is inserted into the opening, which has an inner guide surface for forming a sliding bearing for the valve stem; - the sliding bush is screwed directly or indirectly into the housing; A valve seat ring is inserted into the opening in the housing coaxially to the slide bushing. The valve stem guide according to the invention is characterized in that the slide bushing is only inserted into the valve seat ring.

Description

Die vorliegende Erfindung betrifft eine Ventilschaftführung für einen Dampfexpander gemäß dem Oberbegriff von Anspruch 1, sowie einen Dampfexpander mit einer solchen Ventilschaftführung.The present invention relates to a valve stem guide for a steam expander according to the preamble of claim 1, and to a steam expander with such a valve stem guide.

Gattungsgemäße Ventilschaftführungen werden dazu verwendet, den Ventilschaft eines Einlassventils oder Auslassventils eines Dampfexpanders in Kolbenmaschinenbauart, auch Dampfmotor genannt, zu führen. Ein solcher Ventilschaft weist einen ventilkörperseitigen Endbereich und einen diesem abgewandten, entsprechend ventilkörperfernen Endbereich auf, zwischen denen sich in der Regel der mittels der Ventilschaftführung geführte Bereich des Ventilschafts erstreckt. Der ventilkörperseitige Endbereich des Ventilschafts trägt und/oder betätigt einen Ventilkörper, der zusammen mit einem Ventilsitz des Ventils einen Einlass oder einen Auslass für das Arbeitsmedium Dampf des Dampfexpanders öffnet und schließt, damit dieses in einzelnen Zyklen (Takten) in den Zylinderraum oder aus dem Zylinderraum des Dampfexpanders strömen kann, je nachdem, ob es sich um ein Einlassventil oder ein Auslassventil handelt.Valve stem guides of the generic type are used to guide the valve stem of an inlet valve or an outlet valve of a steam expander in piston engine design, also called steam engine. Such a valve stem has an end region on the valve body side and an end region facing away from this, correspondingly remote from the valve body, between which the region of the valve stem guided by means of the valve stem guide extends as a rule. The end region of the valve stem on the valve body side carries and / or actuates a valve body which, together with a valve seat of the valve, opens and closes an inlet or an outlet for the working medium steam of the steam expander so that it enters the cylinder chamber or out of the cylinder chamber in individual cycles of the steam expander can flow, depending on whether it is an inlet valve or an outlet valve.

Da an eine solche Ventilschaftführung besondere Gleitanforderungen gestellt werden, wird die Ventilschaftführung häufig mit einer Gleitbuchse versehen oder durch diese gebildet, die in ein Gehäuse, beispielsweise Kurbelgehäuse, des Dampfexpanders eingesetzt ist. Herkömmlich erfolgt das Einsetzen durch Herstellung eines Presssitzes, das heißt das Konstruieren einer sogenannten Übermaßpassung zwischen der Gleitbuchse und des diese umgebenden Gehäuses, um eine kraftschlüssige Verbindung zu erreichen. In der Regel wird das Gehäuse mit einer Öffnung, insbesondere Bohrung, für die Gleitbuchse versehen und die Gleitbuchse wird vor ihrem Einsetzen stark abgekühlt, wobei das Gehäuse gleichzeitig erwärmt werden kann, sodass sich die Gleitbuchse zusammenzieht und die Öffnung in dem Gehäuse insbesondere aufweitet, sodass die Gleitbuchse in die Öffnung eingesetzt werden kann. Nach einem Temperaturausgleich zwischen der Gleitbuchse und dem Gehäuse ergibt sich der gewünschte Presssitz.Since special sliding requirements are placed on such a valve stem guide, the valve stem guide is often provided with or formed by a sliding bushing which is inserted into a housing, for example a crankcase, of the steam expander. Conventionally, the insertion takes place by producing a press fit, that is, the construction of a so-called interference fit between the sliding bush and the housing surrounding it in order to achieve a force-locking connection. As a rule, the housing is provided with an opening, in particular a bore, for the sliding bushing and the sliding bushing is strongly cooled before it is inserted, whereby the housing can be heated at the same time, so that the sliding bushing contracts and the opening in the housing in particular expands so that the sliding bush can be inserted into the opening. After a Temperature equalization between the sliding bush and the housing results in the desired press fit.

Obwohl mit dieser Art der Ausführungsform einer Ventilschaftführung auf eine in der Praxis seit vielen Jahrzehnten übliche Lösung zurückgegriffen wurde, haben sich in der Praxis in jüngerer Zeit beim Betrieb von Dampfexpandern unregelmäßig auftretende Wirkungsgradverluste ergeben, deren Ursache zunächst unklar war. Nachdem es zum Teil auch Beschädigungen an den Einlassventilen und Auslassventilen gab, die zu einem Ausfall des Dampfexpanders führten, haben Untersuchungen ergeben, dass sich während des Betriebs des Dampfexpanders das Öffnungsverhalten und Schließverhalten einzelner Einlassventile und Auslassventile geändert hat.Although this type of embodiment of a valve stem guide was based on a solution that has been common in practice for many decades, in practice there have recently been irregular losses in efficiency during the operation of steam expanders, the cause of which was initially unclear. After the inlet valves and outlet valves were partially damaged, which led to the steam expander failing, investigations have shown that the opening and closing behavior of individual inlet valves and outlet valves has changed during operation of the steam expander.

Gemäß DE 10 2014 218 365 A1 sind die zuvor genannten Probleme darauf zurückzuführen, dass durch eine Temperaturdehnung des Gehäuses sich der Presssitz der Gleitbuchse im Gehäuse vorübergehend gelöst hat, sodass durch eine Kraftbeaufschlagung der Gleitbuchse über die Reibkräfte des Ventilschafts eine Verlagerung der Gleitbuchse innerhalb des Gehäuses stattfinden konnte. Durch im weiteren Betrieb geänderte Temperaturbedingungen wurde der Presssitz erneut hergestellt, jetzt jedoch mit einer anderen Position der Gleitbuchse innerhalb des Gehäuses. DE 10 2014 218 365 A1 schlägt daher vor, die Gleitbuchse in das Gehäuse einzuschrauben, unmittelbar oder mittelbar. Das mittelbare Einschrauben kann durch Einschrauben der Gleitbuchse in einen Ventilsitzring erfolgen.According to DE 10 2014 218 365 A1 The aforementioned problems are due to the fact that the press fit of the sliding bushing in the housing was temporarily loosened due to thermal expansion of the housing, so that the sliding bushing could be displaced within the housing by applying force to the sliding bushing via the frictional forces of the valve stem. The press fit was re-established as the temperature conditions changed during further operation, but now with a different position of the sliding bush within the housing. DE 10 2014 218 365 A1 therefore suggests screwing the sliding bushing into the housing, directly or indirectly. The indirect screwing in can be done by screwing the sliding bush into a valve seat ring.

Die in der DE 10 2014 218 365 A1 vorgeschlagene Ausführungsform, bei welcher insbesondere ein Abstand zwischen der Gleitbuchse und dem Ventilsitzring vorgesehen ist, um thermische Relativdehnungen nicht zu behindern, hat sich in der Praxis als anfällig für Verschleiß und nachfolgend eine Undichtigkeit im Bereich des Ventilsitzringes herausgestellt. Die Ursache war zunächst unbekannt.The ones in the DE 10 2014 218 365 A1 The proposed embodiment, in which in particular a distance is provided between the sliding bushing and the valve seat ring so as not to hinder relative thermal expansion, has proven to be susceptible to wear and tear and subsequently a leak in the area of the valve seat ring in practice. The cause was initially unknown.

Der vorliegenden Erfindung liegt die Aufgabe zugrunde, eine Ventilschaftführung für einen Dampfexpander anzugeben, welcher das Problem des Verschleißes und der Undichtigkeit im Bereich des Ventilsitzringes vermeidet. Die Ventilschaftführung soll sich durch einen besonders zuverlässigen Betrieb der entsprechenden Ventile mit einer hohen Lebensdauer auszeichnen.The present invention is based on the object of specifying a valve stem guide for a steam expander which avoids the problem of wear and leakage in the area of the valve seat insert. The valve stem guide should be characterized by a particularly reliable operation of the corresponding valves with a long service life.

Die erfindungsgemäße Aufgabe wird durch eine Ventilschaftführung mit den Merkmalen von Anspruch 1 gelöst. In den abhängigen Ansprüchen sind vorteilhafte und besonders zweckmäßige Ausgestaltungen sowie ein erfindungsgemäßer Dampfexpander mit einer solchen Ventilschaftführung angegeben.The object of the invention is achieved by a valve stem guide with the features of claim 1. In the dependent claims, advantageous and particularly expedient embodiments and a steam expander according to the invention with such a valve stem guide are specified.

Im Einzelnen weist eine erfindungsgemäße Ventilschaftführung für einen Dampfexpander ein Gehäuse auf, das beispielsweise Bestandteil des Kurbelgehäuses des Dampfexpanders ist. Es ist eine im Gehäuse verlaufende Öffnung zur Aufnahme eines Ventilschafts vorgesehen, wobei die Öffnung insbesondere in Richtung einer Längsachse des Gehäuses verläuft.In detail, a valve stem guide according to the invention for a steam expander has a housing which is, for example, a component of the crankcase of the steam expander. An opening running in the housing is provided for receiving a valve stem, the opening running in particular in the direction of a longitudinal axis of the housing.

In die Öffnung ist erfindungsgemäß eine Gleitbuchse eingesetzt, die eine innere Führungsfläche zur Ausbildung eines Gleitlagers für den Ventilschaft aufweist. Somit kann der Ventilschaft mit seiner äußeren Oberfläche unmittelbar auf der inneren Führungsoberfläche der Gleitbuchse gleiten, wobei vorteilhaft eine Werkstoffpaarung an dieser Schnittstelle beziehungsweise diesem Gleitlager gewählt wird, die günstige Schmiereigenschaften bietet. Beispielswiese ist die Gleitbuchse aus Messing hergestellt und das Gehäuse aus Stahl.According to the invention, a sliding bushing is inserted into the opening which has an inner guide surface for forming a sliding bearing for the valve stem. Thus, the valve stem can slide with its outer surface directly on the inner guide surface of the sliding bush, whereby a material pairing is advantageously chosen at this interface or this sliding bearing that offers favorable lubricating properties. For example, the sliding bush is made of brass and the housing is made of steel.

Erfindungsgemäß ist die Gleitbuchse in das Gehäuse eingeschraubt, entweder unmittelbar, das heißt, dass die Gleitbuchse und das Gehäuse jeweils ein Gewinde aufweisen, wobei die beiden Gewinde miteinander im Eingriff stehen, oder mittelbar, das heißt, dass die Gleitbuchse ein Gewinde aufweist, das mit einem Gewinde eines Konterelementes zusammenarbeitet, das wiederum ortsfest im Gehäuse verriegelt ist.According to the invention, the sliding bushing is screwed into the housing, either directly, that is, the sliding bushing and the housing each have a thread, the two threads being in engagement with one another, or indirectly, that is, the sliding bushing has a thread that is connected to a thread of a counter element cooperates, which in turn is locked in place in the housing.

Erfindungsgemäß ist die Gleitbuchse in den Ventilsitzring nur eingesteckt, das heißt frei von einer Verschraubung eingesteckt. Insbesondere ist die Gleitbuchse lose in den Ventilsitzring eingesteckt, also mit einem Spiel zwischen der Gleitbuchse und dem Ventilsitzring.According to the invention, the sliding bushing is only inserted into the valve seat ring, that is to say inserted free from a screw connection. In particular, the sliding bushing is inserted loosely into the valve seat ring, that is to say with play between the sliding bushing and the valve seat ring.

Der Ventilsitzring weist beispielsweise eine zentrale Bohrung auf, die einen Durchmesser aufweist, der größer ist als der Außendurchmesser der Gleitbuchse, zumindest in dem dem Ventilsitzring zugewandten Ende. Beispielsweise ist der Durchmesser der Bohrung im Ventilsitzring um wenigstens 1/100 mm oder 1/10 mm größer als der Außendurchmesser der Gleitbuchse.The valve seat ring has, for example, a central bore which has a diameter that is greater than the outer diameter of the sliding bush, at least in the end facing the valve seat ring. For example, the diameter of the bore in the valve seat ring is at least 1/100 mm or 1/10 mm larger than the outer diameter of the sliding bush.

Durch das (lose) Einstecken der Gleitbuchse in den Ventilsitzring wird die Gleitbuchse seitlich, insbesondere vollumfänglich an ihrem dem Ventilsitzring zugewandten Ende geführt, sodass bisher auf die Gleitbuchse wirkende Hebelkräfte sicher ohne Verbiegung der Gleitbuchse abgeleitet werden. Insbesondere wird die Gleitbuchse im Bereich des dem Ventilsitzring zugewandten Endes zum einen vom Material des Ventilsitzrings umschlossen und zum anderen angrenzend an den Ventilsitzring vom Material des Gehäuses umschlossen. Es verbleibt demnach kein Freiraum radial außerhalb der Gleitbuchse innerhalb des Gehäuses.By (loosely) inserting the sliding bushing into the valve seat ring, the sliding bushing is guided laterally, in particular over the full circumference of its end facing the valve seat ring, so that leverage forces previously acting on the sliding bushing are safely diverted without bending the sliding bushing. In particular, in the region of the end facing the valve seat ring, the sliding bush is on the one hand enclosed by the material of the valve seat ring and on the other hand is enclosed by the material of the housing adjacent to the valve seat ring. Accordingly, there remains no free space radially outside the sliding bushing inside the housing.

Gemäß einer vorteilhaften Ausführungsform der Erfindung trägt die Gleitbuchse auf einer äußeren Oberfläche ein Außengewinde, mittels welchem die Gleitbuchse in ein in der Öffnung vorgesehenes Innengewinde eingeschraubt ist. Vorteilhaft erstreckt sich das Außengewinde auf der Gleitbuchse nur über einen Teil der axialen Länge der Gleitbuchse. Dies ist günstig, um eine unerwünschte Krafteinleitung in das Gewinde infolge thermischer Dehnungen über der Gewindelänge zu reduzieren. Insbesondere erstreckt sich auch das Innengewinde in dem Gehäuse nur über einen Teil der axialen Erstreckung der Gleitbuchse beziehungsweise des axialen Abschnitts, welchem die Gleitbuchse in der Öffnung gegenübersteht.According to an advantageous embodiment of the invention, the sliding bush has an external thread on an outer surface, by means of which the sliding bush is screwed into an internal thread provided in the opening. The external thread on the sliding bush advantageously extends only over part of the axial length of the sliding bush. This is advantageous in order to reduce undesired introduction of force into the thread as a result of thermal expansions over the thread length. In particular, the internal thread also extends in the housing only over part of the axial extent of the sliding bush or the axial section which the sliding bush faces in the opening.

Gemäß einer vorteilhaften Ausführungsform weist die Gleitbuchse einen Anschlag auf, mittels welchem sie beim Einschrauben der Gleitbuchse in das Gehäuse beziehungsweise im eingeschraubten Zustand der Gleitbuchse in dem Gehäuse am Gehäuse anschlägt. Der Anschlag kann beispielsweise in Form eines in Radialrichtung auf der Gleitbuchse hervorstehenden Bundes ausgeführt sein. Der Anschlag schlägt beispielsweise stirnseitig an einer die Öffnung umschließenden Fläche des Gehäuses an.According to an advantageous embodiment, the sliding bushing has a stop by means of which it strikes the housing when the sliding bushing is screwed into the housing or when the sliding bushing is screwed into the housing. The stop can be designed, for example, in the form of a collar protruding in the radial direction on the sliding bush. The stop strikes, for example, on the end face of a surface of the housing surrounding the opening.

Im Hinblick auf die im Betrieb auftretenden thermischen Dehnungen ist es besonders günstig, wenn das Außengewinde auf der Gleitbuchse in Axialrichtung an den Anschlag angrenzt. Hierdurch kann die Gefahr eines Lösens einer durch Einschrauben in das Gehäuse verspannten Gleitbuchse minimiert werden und nachteilige thermische Dehnungen in dem Gewinde werden reduziert.With regard to the thermal expansions that occur during operation, it is particularly advantageous if the external thread on the sliding bushing adjoins the stop in the axial direction. This can minimize the risk of a sliding bushing that is tensioned by screwing into the housing loosening, and disadvantageous thermal expansions in the thread are reduced.

Um die Gleitbuchse in das Gehäuse einschrauben zu können und insbesondere mit ihrem Anschlag gegen das Gehäuse verspannen zu können, kann die Gleitbuchse an einem axialen Ende ein Mitnahmeprofil aufweisen. Das Mitnahmeprofil kann beispielsweise die Form eines Außensechskants aufweisen. Jedoch sind auch andere Profile möglich, beispielsweise ein Innenantrieb wie Innensechskant oder Torx (Innensechsrund). Auch andere Außenantriebe sind möglich.In order to be able to screw the sliding bushing into the housing and in particular to be able to brace it with its stop against the housing, the sliding bushing can have a driving profile at one axial end. The driving profile can, for example, have the shape of an external hexagon. However, other profiles are also possible, for example an internal drive such as hexagon socket or Torx (hexalobular socket). Other external drives are also possible.

Gemäß einer Ausführungsform ist das Mitnahmeprofil an dem axialen Ende der Gleitbuchse vorgesehen, an dem das Außengewinde und insbesondere der Anschlag positioniert ist.According to one embodiment, the driving profile is provided at the axial end of the sliding bushing, on which the external thread and in particular the stop is positioned.

Der gemäß der Erfindung koaxial zur Gleitbuchse im Gehäuse eingesetzte Ventilsitzring bildet bevorzugt einen Ventilsitz für das Einlassventil oder Auslassventil aus, welchem der Ventilschaft zugeordnet ist. Der Ventilschaft trägt beispielsweise, wie eingangs dargestellt, an seinem axialen Ende, das vorteilhaft vom Ventilsitzring mehr oder minder umschlossen wird, einen Ventilkörper, der dann zusammen mit dem Ventilsitz den Öffnungsquerschnitt des Ventils in Abhängigkeit der relativen Position des Ventilkörpers zum Ventilsitz mehr oder minder beschränkt.According to the invention, the valve seat ring inserted coaxially to the sliding bushing in the housing preferably forms a valve seat for the inlet valve or outlet valve to which the valve stem is assigned. The valve stem carries, for example, as shown at the beginning, at its axial end, which is advantageously more or less enclosed by the valve seat insert, a valve body which, together with the valve seat, more or less restricts the opening cross-section of the valve depending on the position of the valve body relative to the valve seat .

Um den Ventilsitzring aufzunehmen, kann die Öffnung im Gehäuse an ihrem dem Ventilsitzring zugewandten axialen Ende stufenförmig erweitert ausgeführt sein, sodass sich der Durchmesser der Öffnung in einer Stufe auf einen vergleichsweise größeren Durchmesser erweitert, der dem Außendurchmesser des Ventilsitzringes angepasst ist. Der Ventilsitzring kann gemäß einer Ausführungsform in die Öffnung im Gehäuse eingepresst sein, das heißt zwischen dem Außendurchmesser des Ventilsitzringes und dem Innendurchmesser der Öffnung, insbesondere der Erweiterung in der Öffnung ist eine Untermaßpassung vorgesehen. Jedoch ist es auch möglich, den Ventilsitzring anders in das Gehäuse einzubringen, beispielsweise einzukleben, zu verstemmen, anzuschweißen oder einzuschrauben.In order to accommodate the valve seat ring, the opening in the housing can be designed to be stepped widened at its axial end facing the valve seat ring, so that the diameter of the opening expands in one step to a comparatively larger diameter that is adapted to the outer diameter of the valve seat ring. According to one embodiment, the valve seat insert can be pressed into the opening in the housing, that is, an undersize fit is provided between the outer diameter of the valve seat insert and the inner diameter of the opening, in particular the widening in the opening. However, it is also possible to introduce the valve seat ring into the housing in a different way, for example to glue, caulk, weld or screw it in.

Es ist nicht zwingend notwendig, dass in einem Dampfexpander alle Ventilschaftführungen mit in die Ventilsitzringe eingesteckten Gleitbuchsen ausgeführt sind. Vielmehr kann nur ein Teil der Ventilschaftführungen entsprechend ausgeführt sein, wohingegen bei einem anderen Teil der Ventilschaftführungen ein Axialspalt zwischen dem Ventilsitzring und der Gleitbuchse vorgesehen ist, nämlich bei solchen Ventilschaftführungen, auf die eine geringere Hebelkraft wirkt.It is not absolutely necessary that all valve stem guides in a steam expander are designed with sliding bushings inserted into the valve seat rings. Rather, only a part of the valve stem guides can be designed accordingly, whereas in another part of the valve stem guides an axial gap is provided between the valve seat ring and the sliding bush, namely in valve stem guides on which a lower leverage acts.

Ein erfindungsgemäßer Dampfexpander weist wenigstens einen Zylinder oder eine Vielzahl von Zylindern, beispielsweise zwei Zylinder, auf, die jeweils einen Zylinderraum und einen Zylinderkolben aufweisen. Durch Dampfexpansion in dem Zylinderraum wird der Zylinderkolben verschoben und kann eine Kurbelwelle antreiben.A steam expander according to the invention has at least one cylinder or a plurality of cylinders, for example two cylinders, each one Have a cylinder space and a cylinder piston. The cylinder piston is displaced by steam expansion in the cylinder space and can drive a crankshaft.

Der oder jeder Zylinderraum ist über ein Einlassventil mit einer Dampfzufuhr des Dampfexpanders und über ein Auslassventil mit einer Dampfabfuhr des Dampfexpanders verbunden. Wenigstens ein Einlassventil, das die Dampfzufuhr nach dem Befüllen des Zylinderraumes mit Dampf absperrt, und/oder ein Auslassventil, das die Dampfabfuhr nach dem Abführen des Dampfes aus dem Zylinderraum versperrt, weist/weisen einen Ventilsitz, einen Ventilkörper und einen am Ventilkörper zu dessen Bewegung relativ zum Ventilsitz angeschlossenen Ventilschaft auf, der in einer erfindungsgemäßen Ventilschaftführung gleitbar gelagert ist.The or each cylinder space is connected to a steam supply of the steam expander via an inlet valve and to a steam outlet of the steam expander via an outlet valve. At least one inlet valve, which shuts off the steam supply after the cylinder space has been filled with steam, and / or an outlet valve, which blocks the steam discharge after the steam has been discharged from the cylinder space, has / have a valve seat, a valve body and one on the valve body for its movement relative to the valve seat connected valve stem, which is slidably mounted in a valve stem guide according to the invention.

Die Erfindung soll nachfolgend anhand von Ausführungsbeispielen und den Figuren exemplarisch erläutert werden.The invention is to be explained below using exemplary embodiments and the figures.

Es zeigen:

Figur 1
einen Teil eines Dampfexpanders im Bereich des Einlassventils, jedoch noch ohne die erfindungsgemäße Ventilschaftführung;
Figur 2
ein Ausführungsbeispiel eines Dampfexpanders mit zwei erfindungsgemäß ausgeführten Ventilschaftführungen.
Show it:
Figure 1
part of a steam expander in the area of the inlet valve, but still without the valve stem guide according to the invention;
Figure 2
an embodiment of a steam expander with two valve stem guides designed according to the invention.

In der Figur 1 ist der Bereich eines Einlassventils 15 eines Dampfexpanders dargestellt. Das Einlassventil 15 öffnet und verschließt den Strömungsquerschnitt für Dampf einer Dampfzufuhr 18, über welche der Dampf in den Zylinderraum 19 des Dampfexpanders geleitet wird. Im Zylinderraum 19 bewegt der expandierende Dampf den Zylinderkolben 20 entlang der Zylinderbuchse 21 und treibt damit über die Kolbenstange 22 eine hier nicht näher dargestellte Kurbelwelle an. Die Zylinderbuchse 21 bildet mit der äußeren Oberfläche 23 des Zylinderkolbens 20 eine hinsichtlich der Gleiteigenschaften optimierte Paarung. Dies ist jedoch nicht zwingend notwendig, vielmehr könnte der Zylinderkolben 20 auch unmittelbar an einer Oberfläche des Gehäuses 1 gleiten.In the Figure 1 the area of an inlet valve 15 of a steam expander is shown. The inlet valve 15 opens and closes the flow cross section for steam of a steam supply 18, via which the steam is passed into the cylinder space 19 of the steam expander. In the cylinder chamber 19, the expanding steam moves the cylinder piston 20 along the cylinder liner 21 and thus drives a piston rod 22 that is not shown in detail here Crankshaft. The cylinder liner 21 and the outer surface 23 of the cylinder piston 20 form a pairing that is optimized with regard to the sliding properties. However, this is not absolutely necessary; rather, the cylinder piston 20 could also slide directly on a surface of the housing 1.

In das Gehäuse 1 ist ferner eine Gleitbuchse 5 eingesetzt, in welcher der Ventilschaft 4 des Einlassventils 15 gleitet. Im gezeigten Ausführungsbeispiel weist die Gleitbuchse 5 eingesetzte Gleitelemente 24 auf, die ein Gleitlager für den Ventilschaft 4 bilden. Demnach weisen die Gleitelemente 24 eine Führungsoberfläche 6 für den Ventilschaft 4 auf. Dies ist jedoch nicht zwingend notwendig, vielmehr könnte der Ventilschaft 4 auch unmittelbar im Grundkörper der Gleitbuchse 5 gleiten, sodass die innere Oberfläche 25 die Führungsoberfläche für den Ventilschaft 4 bilden würde.In the housing 1, a sliding bush 5 is also inserted, in which the valve stem 4 of the inlet valve 15 slides. In the exemplary embodiment shown, the sliding bush 5 has inserted sliding elements 24 which form a sliding bearing for the valve stem 4. Accordingly, the sliding elements 24 have a guide surface 6 for the valve stem 4. However, this is not absolutely necessary; rather, the valve stem 4 could also slide directly in the base body of the sliding bush 5, so that the inner surface 25 would form the guide surface for the valve stem 4.

Der Ventilschaft 4 trägt an einem axialen Ende den Ventilkörper 17, der mit dem Ventilsitz 12 zusammenarbeitet, um durch Variieren des Abstands des Ventilkörpers 17 zum Ventilsitz 12 den Strömungsquerschnitt in der Dampfzufuhr 18 einzustellen. Der Ventilsitz 12 wird hier durch einen Ventilsitzring 11, der in das Gehäuse 1 eingesetzt ist, gebildet, könnte jedoch auch unmittelbar im Gehäuse 1 ausgeführt sein.At one axial end, the valve stem 4 carries the valve body 17, which cooperates with the valve seat 12 in order to adjust the flow cross-section in the steam supply 18 by varying the distance between the valve body 17 and the valve seat 12. The valve seat 12 is formed here by a valve seat ring 11 which is inserted into the housing 1, but could also be implemented directly in the housing 1.

Abweichend von der vorliegenden Erfindung ist die Gleitbuchse 5 nicht bis zum Ventilsitzring 11 verlängert und in diesen eingesteckt, sondern es ist ein Abstand zwischen der Gleitbuchse 5 und dem Ventilsitzring 11 vorgesehen. Die übrigen hier dargestellten Merkmale können jedoch auch bei einer erfindungsgemäß ausgeführten Ventilschaftführung vorgesehen werden.In a departure from the present invention, the sliding bush 5 is not extended up to the valve seat ring 11 and inserted into it, but a distance between the sliding bush 5 and the valve seat ring 11 is provided. The other features shown here can, however, also be provided in a valve stem guide designed according to the invention.

Am anderen Ende des Ventilschafts 4 ist ein Federelement 26 vorgesehen, das hier im Sinne eines Schließens des Einlassventils 15 wirkt. Somit kann das Einlassventil 15 durch Aufbringen einer Kraft mittels einer hier nicht dargestellten Nockenwelle auf den Ventilschaft 4 entgegen der Kraft des Federelementes 26, hier in Form einer Druckfeder, geöffnet werden.At the other end of the valve stem 4, a spring element 26 is provided, which here acts to close the inlet valve 15. Thus, the inlet valve 15 can by applying a force by means of a not shown here Camshaft on the valve stem 4 against the force of the spring element 26, here in the form of a compression spring, are opened.

Die Gleitbuchse 5 weist über einen Teilbereich des axialen Abschnitts der in die Öffnung 3 im Gehäuse 1 eingefügten äußeren Oberfläche 7, hier über deutlich weniger als die halbe axiale Länge der eingefügten äußeren Oberfläche 7 ein Außengewinde 8 auf, das in ein Innengewinde 9 in der Öffnung 3 eingeschraubt ist, und zwar derart, dass die Gleitbuchse 5 mit dem vorstehenden Bund 27 an einer Stirnseite des Gehäuses in Axialrichtung der Öffnung 3 anschlägt und verspannt ist. Hierdurch wird auch dann ein Verrutschen der Gleitbuchse 5 innerhalb der Öffnung 3 verhindert, wenn das Gehäuse 1 im Bereich der Öffnung 3 aufgrund der Nähe zum Zylinderraum 19 und zur Dampfzufuhr 18 stärker erwärmt wird als die eingesetzte Gleitbuchse 5 und damit einer stärkeren Wärmedehnung unterliegt.The sliding bush 5 has over a portion of the axial section of the outer surface 7 inserted into the opening 3 in the housing 1, here over significantly less than half the axial length of the inserted outer surface 7, an external thread 8 which is inserted into an internal thread 9 in the opening 3 is screwed in, in such a way that the sliding bush 5 strikes with the protruding collar 27 on an end face of the housing in the axial direction of the opening 3 and is braced. This also prevents the sliding bush 5 from slipping within the opening 3 if the housing 1 in the area of the opening 3 is heated more than the inserted sliding bush 5 due to its proximity to the cylinder chamber 19 and the steam supply 18 and is therefore subject to greater thermal expansion.

In der Figur 2 sind weitere Ventilschaftführungen des Dampfexpanders gezeigt, wobei die beiden mittleren dargestellten Ventilschaftführungen erfindungsgemäß ausgeführt sind, die beiden äußeren hingegen abweichend. Sich entsprechende Elemente sind mit sich entsprechenden Bezugszeichen beziffert.In the Figure 2 further valve stem guides of the steam expander are shown, the two middle valve stem guides shown being designed according to the invention, whereas the two outer ones are different. Corresponding elements are numbered with corresponding reference symbols.

Beim Ausführungsbeispiel gemäß der Figur 2 sind vier Öffnungen 3 mit eingesetzten Gleitbuchsen 5 vorgesehen, wobei die beiden mittleren zur Führung des Ventilschafts 4 jeweils eines Einlassventils 15 dienen und die beiden äußeren zur Führung eines Ventilschafts 4 von Auslassventilen 16. Die Gleitbuchsen 5 weisen wiederum einen Bund 27 als Anschlag auf, zum Verspannen der jeweiligen Gleitbuchse 5 im Gehäuse 1, wenn die Gleitbuchse 5 mit ihrem Außengewinde 8 in das Innengewinde 9 in der Öffnung 3 eingeschraubt wird. Im Bereich des axialen Endes der Gleitbuchse 5 mit dem Bund 27 ist ein Mitnahmeprofil 10, beispielsweise in Form eines Außensechskants, vorgesehen, der einen Antrieb zum Einschrauben der Gleitbuchse 5 in das Gehäuse 1 bietet.In the embodiment according to Figure 2 four openings 3 with inserted slide bushings 5 are provided, the two middle ones serving to guide the valve stem 4 each of an inlet valve 15 and the two outer ones to guide a valve stem 4 of outlet valves 16. The sliding bushings 5 in turn have a collar 27 as a stop, for The respective sliding bush 5 is braced in the housing 1 when the sliding bush 5 is screwed with its external thread 8 into the internal thread 9 in the opening 3. In the area of the axial end of the sliding bush 5 with the collar 27, a driving profile 10, for example in the form of an external hexagon, is provided, which provides a drive for screwing the sliding bush 5 into the housing 1.

In Richtung der Längsachse 2 jeder Öffnung 3 ist neben der Gleitbuchse 5 ein Ventilsitzring 11 in die Öffnung 3 eingefügt, der einen Ventilsitz 12 ausbildet. Bei den Ventilsitzringen 11, die koaxial zu den Gleitbuchsen 5 der äußeren Öffnungen 3 in das Gehäuse 1 eingesetzt sind, entspricht die Gestalt weitgehend jener des Ventilsitzringes 11 gemäß der Figur 1. Die Ventilschaftführung weist einen Axialspalt 14 zwischen den Gleitbuchsen 5 und den Ventilsitzringen 11 auf. Die beiden inneren Ventilsitzringe 11 hingegen weisen eine deutlich größere axiale Erstreckung (Erstreckung in Richtung der Längsachse 2) auf und schließen im Gegensatz zu den äußeren Ventilsitzringen 11 nicht bündig mit dem Gehäuse 1 ab, sondern stehen aus diesem hervor und ragen in einen aufgesetzten Deckel hinein.In the direction of the longitudinal axis 2 of each opening 3, a valve seat ring 11, which forms a valve seat 12, is inserted into the opening 3 in addition to the sliding bush 5. In the case of the valve seat rings 11, which are inserted coaxially to the sliding bushings 5 of the outer openings 3 in the housing 1, the shape largely corresponds to that of the valve seat ring 11 according to FIG Figure 1 . The valve stem guide has an axial gap 14 between the slide bushings 5 and the valve seat rings 11. The two inner valve seat rings 11, on the other hand, have a significantly larger axial extent (extent in the direction of the longitudinal axis 2) and, in contrast to the outer valve seat rings 11, do not end flush with the housing 1, but protrude from it and protrude into an attached cover .

Abweichend von der Darstellung gemäß der Figur 1 wird beim Ausführungsbeispiel gemäß der Figur 2 die Führungsoberfläche 6 der Gleitbuchsen 5 unmittelbar durch die innere Oberfläche 25 der Gleitbuchsen 5 gebildet.Deviating from the representation according to Figure 1 is in the embodiment according to Figure 2 the guide surface 6 of the sliding bushes 5 is formed directly by the inner surface 25 of the sliding bushes 5.

Die beiden äußeren Gleitbuchsen 5 werden in Umfangsrichtung nur vom Gehäuse 1 umschlossen. Die beiden inneren Gleitbuchsen 5 hingegen erstrecken sich bis in den jeweiligen Ventilsitzring 11 hinein und sind in diesen eingesteckt. Damit bewirkt der jeweilige Ventilsitzring 11 eine radiale Führung der Gleitbuchse 5 und verhindert ein Verbiegen derselben. Die Gleitbuchse 5 ist dabei "frei" in den Ventilsitzring 11 eingesteckt, ohne eine Verschraubung oder eine Hinterschneidung, sodass unterschiedliche thermische Dehnungen der Gleitbuchse 5 und des Ventilsitzringes 11 beziehungsweise des Gehäuses 1 nicht behindert werden und sich die Gleitbuchse 5 in Richtung der Längsachse 2 im Ventilsitzring 11 bewegen kann.The two outer sliding bushings 5 are only enclosed by the housing 1 in the circumferential direction. The two inner sliding bushings 5, however, extend into the respective valve seat ring 11 and are inserted into it. The respective valve seat ring 11 thus effects a radial guidance of the sliding bush 5 and prevents it from bending. The sliding bush 5 is "freely" inserted into the valve seat ring 11, without a screw connection or an undercut, so that different thermal expansions of the sliding bush 5 and the valve seat ring 11 or the housing 1 are not hindered and the sliding bush 5 moves in the direction of the longitudinal axis 2 Valve seat ring 11 can move.

In der Figur 2 ist ferner die Position der Kurbelwelle 28 gezeigt, die durch die hier nicht gezeigten Zylinderkolben über die Kolbenstangen angetrieben wird. Ferner ist auch die Position der Nockenwelle 29 gezeigt, deren Nocken (nicht im Einzelnen sondern nur ansatzweise dargestellt) die Ventilschäfte 4 entgegen der Kraft der Federelemente 26 betätigen. Die Federelemente 26 stützen sich außerhalb des Bundes 27 diesen umschließend stirnseitig am Gehäuse 1 ab.In the Figure 2 the position of the crankshaft 28 is also shown, which is driven by the cylinder piston, not shown here, via the piston rods. The position of the camshaft 29 is also shown, the cams of which (not in Individually but only partially shown) actuate the valve stems 4 against the force of the spring elements 26. The spring elements 26 are supported outside the collar 27 at the end of the housing 1, enclosing it.

Claims (9)

Ventilschaftführung für einen Dampfexpander
mit einem Gehäuse (1);
mit wenigstens einer im Gehäuse (1) verlaufenden Öffnung (3) zur Aufnahme eines Ventilschafts (4); wobei
in die Öffnung (3) eine Gleitbuchse (5) eingesetzt ist, die eine innere Führungsoberfläche (6) zur Ausbildung eines Gleitlagers für den Ventilschaft (4) aufweist;
die Gleitbuchse (5) unmittelbar oder mittelbar in das Gehäuse (1) eingeschraubt ist; wobei
koaxial zur Gleitbuchse (5) ein Ventilsitzring (11) in die Öffnung (3) im Gehäuse (1) eingesetzt ist: dadurch gekennzeichnet, dass die Gleitbuchse (5) in den Ventilsitzring (11) nur eingesteckt ist. Valve stem guide for a steam expander
with a housing (1);
with at least one opening (3) running in the housing (1) for receiving a valve stem (4); in which
a slide bushing (5) is inserted into the opening (3) and has an inner guide surface (6) for forming a slide bearing for the valve stem (4);
the sliding bush (5) is screwed directly or indirectly into the housing (1); in which
A valve seat ring (11) is inserted into the opening (3) in the housing (1) coaxially to the sliding bush (5): characterized in that the sliding bush (5) is only inserted into the valve seat ring (11). Ventilschaftführung gemäß Anspruch 1, dadurch gekennzeichnet, dass die Gleitbuchse (5) auf einer äußeren Oberfläche (7) ein Außengewinde (8) aufweist, mittels welchem die Gleitbuchse (5) in ein in die Öffnung (3) eingebrachtes Innengewinde (9) eingeschraubt ist.Valve stem guide according to Claim 1, characterized in that the sliding bush (5) has an external thread (8) on an outer surface (7), by means of which the sliding bush (5) is screwed into an internal thread (9) introduced into the opening (3) . Ventilschaftführung gemäß Anspruch 2, dadurch gekennzeichnet, dass das Außengewinde (8) und insbesondere auch das Innengewinde (9) nur über einen Teil der axialen Erstreckung der Öffnung (3) in dem Gehäuse (1) und nur über einen Teil der axialen Erstreckung der Gleitbuchse (5) reicht/reichen.Valve stem guide according to claim 2, characterized in that the external thread (8) and in particular the internal thread (9) only over part of the axial extent of the opening (3) in the housing (1) and only over part of the axial extent of the sliding bush (5) range / range. Ventilschaftführung gemäß Anspruch 3, dadurch gekennzeichnet, dass die Gleitbuchse (5) einen Anschlag, insbesondere in Form eines in Radialrichtung vorstehenden Bundes (27) aufweist, mit welchem sie beim Einschrauben der Gleitbuchse (5) in das Gehäuse (1) am Gehäuse (1) anschlägt, und dass das Außengewinde (8) in Axialrichtung an dem Anschlag angrenzt.Valve stem guide according to Claim 3, characterized in that the sliding bush (5) has a stop, in particular in the form of a collar (27) protruding in the radial direction, with which it is attached to the housing (1) when the sliding bush (5) is screwed into the housing (1) ) strikes, and that the external thread (8) adjoins the stop in the axial direction. Ventilschaftführung gemäß einem der Ansprüche 1 bis 4, dadurch gekennzeichnet, dass die Gleitbuchse (5) an einem axialen Ende ein Mitnahmeprofil (10), insbesondere in Form eines Außensechskants aufweist.Valve stem guide according to one of Claims 1 to 4, characterized in that the slide bushing (5) has a driving profile (10), in particular in the form of an external hexagon, at one axial end. Ventilschaftführung gemäß einem der Ansprüche 1 bis 5, dadurch gekennzeichnet, dass die Öffnung (3) insbesondere an einem ihrer axialen Enden stufenförmig ausgeführt ist, mit einer Erweiterung (13), in welche der Ventilsitzring (11) eingesetzt ist.Valve stem guide according to one of claims 1 to 5, characterized in that the opening (3) is designed in a stepped manner, in particular at one of its axial ends, with an extension (13) into which the valve seat ring (11) is inserted. Ventilschaftführung gemäß Anspruch 6, dadurch gekennzeichnet, dass der Ventilsitzring (11) in die Öffnung (3) eingepresst ist, insbesondere mit einer Übermaßpassung.Valve stem guide according to Claim 6, characterized in that the valve seat ring (11) is pressed into the opening (3), in particular with an interference fit. Ventilschaftführung gemäß einem der Ansprüche 1 bis 7, dadurch gekennzeichnet, dass die Gleitbuchse (5) mit einem Spiel in den Ventilsitzring (11) eingesteckt ist.Valve stem guide according to one of Claims 1 to 7, characterized in that the sliding bush (5) is inserted into the valve seat ring (11) with some play. Dampfexpander
mit wenigstens einem oder einer Vielzahl von Zylindern, die einen Zylinderraum (19) und einen Zylinderkolben (20) aufweisen, wobei der Zylinderraum (19) über ein Einlassventil (15) mit einer Dampfzufuhr (18) und ein Auslassventil (16) mit einer Dampfabfuhr verbunden ist, und wenigstens ein Einlassventil (15) und/oder ein Auslassventil (16) einen Ventilsitz (12), einen Ventilkörper (17) und einen am Ventilkörper (17) zu dessen Bewegung relativ zum Ventilsitz (12) angeschlossenen Ventilschaft (4) aufweist, der in einer Ventilschaftführung gemäß einem der Ansprüche 1 bis 8 gleitbar gelagert ist.Steam expander
with at least one or a plurality of cylinders which have a cylinder chamber (19) and a cylinder piston (20), the cylinder chamber (19) having an inlet valve (15) with a steam supply (18) and an outlet valve (16) with a steam outlet is connected, and at least one inlet valve (15) and / or one outlet valve (16) a valve seat (12), a valve body (17) and a valve stem (4) connected to the valve body (17) for its movement relative to the valve seat (12) which is slidably mounted in a valve stem guide according to one of claims 1 to 8.
EP20150411.5A 2019-03-01 2020-01-07 Steam expander and valve shaft guide for a steam expander Active EP3702589B1 (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DE102019202834.9A DE102019202834A1 (en) 2019-03-01 2019-03-01 Valve stem guide for a steam expander and steam expander

Publications (2)

Publication Number Publication Date
EP3702589A1 true EP3702589A1 (en) 2020-09-02
EP3702589B1 EP3702589B1 (en) 2022-02-23

Family

ID=69143408

Family Applications (1)

Application Number Title Priority Date Filing Date
EP20150411.5A Active EP3702589B1 (en) 2019-03-01 2020-01-07 Steam expander and valve shaft guide for a steam expander

Country Status (2)

Country Link
EP (1) EP3702589B1 (en)
DE (1) DE102019202834A1 (en)

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2216512A1 (en) * 1972-04-06 1973-10-18 Teledyne Ind EXHAUST DEVICE FOR COMBUSTION ENGINES
JPS60184913A (en) * 1984-03-05 1985-09-20 Komatsu Ltd Intake valve device for steam prime mover
JP3038091B2 (en) * 1992-11-19 2000-05-08 株式会社いすゞセラミックス研究所 Gas engine using ceramic valve
KR101193713B1 (en) * 2003-05-29 2012-10-22 이턴 코포레이션 High temperature corrosion and oxidation resistant valve guide for engine application
US20130025571A1 (en) * 2010-04-21 2013-01-31 Toyota Jidosha Kabushiki Kaisha Internal combustion engine
DE102014218365A1 (en) 2014-09-12 2016-03-17 Steamdrive Gmbh Valve stem guide for a steam expander and steam expander

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB190519695A (en) * 1905-09-29 1906-09-27 Charles Cheers Wakefield Improvements in or relating to Internal Combustion Engines.
GB202028A (en) * 1922-05-10 1923-08-10 Charles Frederick Ryland Improvements in valve guides for internal combustion engines
US3137211A (en) * 1961-05-01 1964-06-16 Jr Russell Grinnell Compound uniflow steam engine
US6135080A (en) * 1998-12-14 2000-10-24 Kallina; Henry D. Valve guide system and method

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2216512A1 (en) * 1972-04-06 1973-10-18 Teledyne Ind EXHAUST DEVICE FOR COMBUSTION ENGINES
JPS60184913A (en) * 1984-03-05 1985-09-20 Komatsu Ltd Intake valve device for steam prime mover
JP3038091B2 (en) * 1992-11-19 2000-05-08 株式会社いすゞセラミックス研究所 Gas engine using ceramic valve
KR101193713B1 (en) * 2003-05-29 2012-10-22 이턴 코포레이션 High temperature corrosion and oxidation resistant valve guide for engine application
US20130025571A1 (en) * 2010-04-21 2013-01-31 Toyota Jidosha Kabushiki Kaisha Internal combustion engine
DE102014218365A1 (en) 2014-09-12 2016-03-17 Steamdrive Gmbh Valve stem guide for a steam expander and steam expander

Also Published As

Publication number Publication date
DE102019202834A1 (en) 2020-09-03
EP3702589B1 (en) 2022-02-23

Similar Documents

Publication Publication Date Title
EP1749146B1 (en) Camshaft adjuster
DE102010011454A1 (en) Reciprocating internal combustion engine with decompression engine brake
DE19915532B4 (en) Switchable valve drive member
EP2634385B1 (en) Adjustable Camshaft
EP3268641B1 (en) Connecting rod with a ball and socket joint
DE19642718A1 (en) Tappet for a valve train of an internal combustion engine
DE102005020580B4 (en) Switchable cam follower
DE102017121425A1 (en) Connecting rod for a variable compression internal combustion engine
EP3702589B1 (en) Steam expander and valve shaft guide for a steam expander
DE102013223685A1 (en) Plug for a camshaft
DE102017125699B3 (en) Roller tappet for a high-pressure fuel pump
WO2020038513A1 (en) Tappet for a fuel pump or for a valve drive
AT521501B1 (en) Length-adjustable connecting rod with press connection
DE102016120943A1 (en) Connecting rod with adjusting mechanism between connecting rod and piston rod
DE102014218365A1 (en) Valve stem guide for a steam expander and steam expander
DE102016124579B3 (en) Autonomous hydraulic support element
EP3339602B1 (en) Connecting rod for a combustion engine with variable compression
DE102011108304B4 (en) Drive unit and thus equipped fluid actuated working cylinder
DE102007037332A1 (en) Switchable support device for a valve train of an internal combustion engine
AT524567B1 (en) Length-adjustable connecting rod with compact drain valve
AT524662B1 (en) Length-adjustable connecting rod with screw collar
DE102008005768A1 (en) Supporting element for valve impulse lever, such as tilting or rocker lever, is formed as hydraulic clearance compensation element for valve gear of internal-combustion engine
DE102016120942A1 (en) Connecting rod with stepped piston
AT519300B1 (en) Length adjustable connecting rod with cylinder-piston unit with gap seal and elastic piston collar
DE102016120948A1 (en) Connecting rod with adjustment mechanism between connecting rod and connecting rod

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE APPLICATION HAS BEEN PUBLISHED

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: REQUEST FOR EXAMINATION WAS MADE

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

AX Request for extension of the european patent

Extension state: BA ME

17P Request for examination filed

Effective date: 20200820

RBV Designated contracting states (corrected)

Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

GRAP Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOSNIGR1

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: GRANT OF PATENT IS INTENDED

INTG Intention to grant announced

Effective date: 20210920

GRAS Grant fee paid

Free format text: ORIGINAL CODE: EPIDOSNIGR3

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE PATENT HAS BEEN GRANTED

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

REG Reference to a national code

Ref country code: GB

Ref legal event code: FG4D

Free format text: NOT ENGLISH

REG Reference to a national code

Ref country code: CH

Ref legal event code: EP

REG Reference to a national code

Ref country code: DE

Ref legal event code: R096

Ref document number: 502020000660

Country of ref document: DE

REG Reference to a national code

Ref country code: AT

Ref legal event code: REF

Ref document number: 1470621

Country of ref document: AT

Kind code of ref document: T

Effective date: 20220315

REG Reference to a national code

Ref country code: IE

Ref legal event code: FG4D

Free format text: LANGUAGE OF EP DOCUMENT: GERMAN

REG Reference to a national code

Ref country code: LT

Ref legal event code: MG9D

REG Reference to a national code

Ref country code: NL

Ref legal event code: MP

Effective date: 20220223

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: SE

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20220223

Ref country code: RS

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20220223

Ref country code: PT

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20220623

Ref country code: NO

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20220523

Ref country code: NL

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20220223

Ref country code: LT

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20220223

Ref country code: HR

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20220223

Ref country code: ES

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20220223

Ref country code: BG

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20220523

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: PL

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20220223

Ref country code: LV

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20220223

Ref country code: GR

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20220524

Ref country code: FI

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20220223

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: IS

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20220623

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: SM

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20220223

Ref country code: SK

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20220223

Ref country code: RO

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20220223

Ref country code: EE

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20220223

Ref country code: DK

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20220223

Ref country code: CZ

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20220223

REG Reference to a national code

Ref country code: DE

Ref legal event code: R097

Ref document number: 502020000660

Country of ref document: DE

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: AL

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20220223

PLBE No opposition filed within time limit

Free format text: ORIGINAL CODE: 0009261

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT

26N No opposition filed

Effective date: 20221124

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: SI

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20220223

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: FR

Payment date: 20230125

Year of fee payment: 4

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: IT

Payment date: 20230131

Year of fee payment: 4

Ref country code: DE

Payment date: 20230118

Year of fee payment: 4

REG Reference to a national code

Ref country code: CH

Ref legal event code: PL

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: LU

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20230107

REG Reference to a national code

Ref country code: BE

Ref legal event code: MM

Effective date: 20230131

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: LI

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20230131

Ref country code: CH

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20230131

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: BE

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20230131

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: IE

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20230107