JP6032658B2 - Rod scraping device and reciprocating piston engine equipped with the device - Google Patents

Description

  The present invention is an apparatus for scraping a circumferential surface of a rod to which a fluid is attached, wherein the apparatus is adjusted to a rod size, and the rod is movable in an axial direction through an opening of the apparatus. Is provided with at least two scraper layer plates of axially offset and each divided and individually variable in radial direction, each having an annular groove opened radially inwardly into which each of the layer plates enters, and divided design The radial holder can receive a radial protrusion on a common holder ring which is also radially variable by means of a spring arrangement corresponding to the radial outer surface of the holder ring, so that The present invention relates to an apparatus that enables a spring-biased adaptation.

  The invention further relates to a crosshead reciprocating piston engine, in particular in the form of a large two-stroke uniflow internal combustion engine equipped with such a device.

  In a known configuration of this type, the scraping layer plate is supported rigidly radially on the corresponding groove bottom so as to have the same fixed inner diameter cooperating with the rod. The hydrodynamic support force generated in the fluid film in the gap between the rod and the rod scraping scraper layer plate is balanced with the spring force acting on the holder ring. For this reason, the radial position of the holder ring and the size of the gap between the rod and its laminar plate are determined by the main scraper laminating plate in a set of scraper laminating plates, and the component due to rod rotation also affects the rod movement pattern. However, it is determined by first cooperating with a predetermined region in the actual direction of the rod moving in the axial direction. The main scraper layer plate reduces the fluid film thickness by half. For this reason, it becomes difficult for the next layer plate to effectively reach the fluid film and scrape off more reliably. As a result, fluid scraping is insufficient and a relatively thick fluid film remains on the rod. When the scraped rod is a piston rod of a crosshead motor, if the cylinder lubricating oil contaminated with combustion residues comes into contact with the piston rod in the upper region of the crankcase, the piston rod that moves up and down according to the above result, This system oil must be clean enough for bearing lubrication and hydraulics because the cylinder case will be contaminated with a relatively large amount of cylinder lubricant and combustion residue from the top, and the system oil in the crankcase will be contaminated. The inconvenience of having to filter frequently.

  U.S. Pat. No. 6,089,077 discloses an oil scraper ring used when filling a rod or shaft hole having a scraping ring member with two scraping edges.

  U.S. Pat. No. 6,089,089 discloses an annular sealing means having a split sealing ring and a split spacer element, a pair of relatively movable, for assembling the split seal ring and split spacer element to form a seal. The entirety is configured to be located in one annular groove of a coaxial member having a circular cross section.

UK Application Publication GB 1265967 US Pat. No. 3,522,949

  From this point of view, it is an object of the present invention to ensure that each scraper layer plate of a common holder ring has an optimum scraping effect.

  According to the invention, this object is achieved by elastically supporting at least the rear layer plate or the at least one main layer plate in the radial direction with respect to the groove bottom of the annular groove of the layer plate, respectively, as viewed in the rod movement direction. Is achieved.

  By these methods, the disadvantages of the known configurations are avoided. Due to the elastic support, each layer plate is individually variable in the radial direction, so that it is adjusted by the force acting in the radial direction. This is because, in particular, the force acting on one layer plate does not affect the other layer plate of the configuration of the present invention at all, and therefore, compared with the known embodiment having a common elastic support portion of the two layer plates. It is advantageous. Depending on the elasticity of its support with respect to the bottom of the groove, each layer plate will return somewhat into the groove of the layer plate, so that the next layer plate that does not return can be effective. Each effective plate reduces the film thickness by half, so the film thickness is greatly reduced by the present invention, and when connecting to the crosshead motor, the cylinder lubricant is clearly separated from the top and the system oil is clearly separated from the bottom. This ensures that the need for system oil filtration that requires a high degree of cleaning is minimized. A further advantage of the present invention is that the falling chemical fluid that frequently invades from the cylinder environment is reduced, thereby reducing the chemical contamination of sensitive system oils, for example, removing chemical contamination that corrodes bearings by filtration. It is not possible to change the system oil, but the need is reduced. A further advantage of the present invention is that the flexible support of the lamella also allows simple wear compensation.

  In the following, further advantageous developments by accumulation of ideas and preferred embodiments will be described.

  Conveniently, each layer plate of the holder ring can be elastically supported in the radial direction. Thereby, in the case of a reciprocating rod, every time the rod strokes, the rod is reliably scraped with the same effect in the front-rear direction or the vertical direction.

  Advantageously, elastic support of the lamellae in the corresponding annular groove can be achieved with a flexible padding inlay, preferably having a so-called O-ring-like profile, and a very simple embodiment at low cost and Become. A simple modification is also possible. Of course, the individual flexible padding inlays in the groove allow other suitable cross-sectional profiles / shapes, as well as cavities, to allow compression to increase or decrease the radial movement of the laminate. Preferably, it should be combined with a suitably selected polymeric material having elastic properties.

  According to another advantageous method for elastically supporting a laminar in a corresponding annular groove, the laminar can be a layer of elastic material of a structure or profile that can be suitably compressed on its radially outer surface. And / or by increasing the biasing force, the lamellae can be moved further radially outward. Such a layer may preferably be integrated with the corresponding layer plate, for example by some vulcanization process, which reduces the number of parts and simplifies assembly. Preferably, the volume of the groove bottom is not completely filled with material, more preferably the material is sponge-like within the groove volume. According to one embodiment, the square cross section of the elastomer does not completely fill the allowed groove volume.

  In fact, the holder ring includes two scraper lamellae, and balanced wear occurs because both lamellae statically define and ensure the support of the holder ring against the rod.

  A further practical method consists in providing the holder ring with at least one discharge outlet opening in the region between the two scraper layer plates. This ensures that the fluid that has been scraped off and collected flows out, avoiding the accumulation of pressure in the space between the lamellae.

  In addition or alternatively, the holder ring comprises at least one respective discharge groove on at least one front (axial) side and / or one outer surface, preferably both front sides and / or both outer surfaces. Fluid that can stop and stop in front of the rear plate (i.e., the flow that has accumulated between the rod surface and the first plate that scraped off a given rod area when the rod has actually moved axially) Body) can surely flow out. Thereby, the operation | work of a corresponding layer board can be simplified. Note that the front (axial) side can coincide with the outer surface.

  In practice, each discharge outlet and / or discharge groove can be in communication with a drain line, which can be connected to an annular ring groove provided in the annular housing for receiving a corresponding holder ring. .

  According to a further preferred embodiment, the holder ring and the laminar are segmented into several more pieces in the circumferential direction so that the rod can be Can be attached to.

  In practice, at least a segment of the holder ring is provided at both ends with overlapping tongues so that the overlapping tongue region is advantageously externally exposed by a cover element arranged on the radially outer surface of the holder ring. Sealed. By these methods, leakage of the scraped fluid can be avoided.

  In order to generate a radially inward force to engage the scraper layer plate with the rod, the holder ring is displaced to a smaller diameter by a spring. To receive the annular spring, the holder ring can advantageously be provided with an annular groove that opens radially outward.

  A further practical method is that at least one of the elements of the device comprises at least one tag, preferably an RFID type tag, containing stored data that clearly defines said element or device. This can simplify the assembly and / or repair of the device according to the invention.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.

It is a longitudinal section of a crosshead type large diesel engine. FIG. 2 is an enlarged view of a lower region of a collection chamber configured as shown in FIG. 1. FIG. 2 is a diagram of a scraping device of this design having two scraper layer plates having the same fixed inner diameter. 1 shows a scraping device according to the present invention. It is a top view of the segmented holder ring. FIG. 6 is a side view of the holder ring according to FIG. 5. It is a figure which shows the example for sealing outside the segmented holder ring.

  A diesel engine as shown in FIG. 1 can be used to drive a marine object, a large power unit or the like. Such an internal combustion engine is used as an example of a reciprocating piston engine with a scope of a crosshead type. Since the basic structure and mode of operation of such a reciprocating engine are well known, they will be described below only when necessary to understand the present invention.

  The engine shown in FIG. 1 includes a crankcase 1 in which a crankshaft 2 is supported by a so-called main bearing. A row of cylinders 3 is arranged on the upper side of the crankcase 1. Each cylinder 3 includes a cylinder liner 4, and a piston 5 that can move up and down is disposed in the cylinder liner 4. The piston 5 functions as a lower limit of movement of the combustion chamber 6 within the liner 4. The cylinder liner 4 is supported on a peripheral housing of a collection chamber 7 that can be filled with collection air or gas.

  The lower portion of the liner 4 extends into the collection chamber 7 and terminates with a gap above the chamber bottom 8. An inlet 9 is provided in the lower end region of the liner 4. When the piston 5 moves up and down, it passes through the inlet 9, thereby opening and closing the communication between the collection chamber 7 and the combustion chamber 6.

  The piston 5 is connected to the corresponding crosshead 10 by a cylinder liner 4 and a piston rod 11 arranged along the axis of the piston 5. The crosshead 10 is designed as a sledge that is positioned in the crankcase 1, moves up and down and is guided by corresponding guides 12 parallel to the axes of the piston 5 and the piston rod 11. The crosshead 10 includes a crosshead pin 13 fixed to the piston rod 11. On this pin 13, a connecting rod 14 for connecting the crosshead 10 to the crankshaft 2 is carried. The collection chamber bottom 8 is placed on the ceiling of the crankcase 1. The piston rod 11 passes through the wall structure constructed by the collection chamber bottom 8 and the crankcase ceiling, whereby the piston rod 11 penetrates the corresponding seal packing 15 provided at the collection chamber bottom 8.

  As long as the cylinder liner is not combusted, an appropriate lubricating oil (referred to as cylinder oil in the present application) that can drop to the collection chamber bottom 8 together with the combustion residue is supplied. In order to process this falling fluid, a drain 16 communicating with the bottom region of the collection chamber 7 is provided. The chamber bottom 8 is inclined toward the drain 16 and / or a ring channel surrounding the seal packing 15 and communicating with the drain 16 is provided. Exhaust gas containing further combustion residues enters the collection chamber 7 when the inlet 9 is open during the downward stroke of the piston 5.

  In the crankcase 1, there is a highly clean oil (referred to as system oil in the present application), and this oil is used for bearing lubrication and hydraulic pressure. A filtration station (not shown) is provided to filter this oil. The crankcase 1 must be separated from the collection chamber 7 in order to prevent the system oil from being contaminated with cylinder oil. For this purpose, a seal packing 15 designed as a stuffing box is provided.

  The stuffing box has an annular housing 17 as best shown in FIG. This housing 17 is arranged in a peripheral socket 18 in the collection chamber bottom 8, which defines a hole through which the piston rod 11 passes. The housing 17 includes an annular groove that opens radially inward. A corresponding ring configuration is seated in each of these grooves. These ring configurations are designed partly as scraper ring 19 and partly as sealing ring 20. In practice, the scraper ring 19 is positioned above the sealing ring 20.

  The purpose of the sealing ring 20 is to overcome the pressure difference between the pressure in the collection box 8 (about 5 bar) and the pressure in the crankcase 1 (about 1 bar), and the purpose of the scraper ring 19 is piston The oil film on the outer surface of the rod 11 is reduced. In this regard, it must be considered that the piston rod 11 above the seal packing 15 contacts the cylinder oil. The cylinder oil is deposited on the outer surface of the piston rod in the form of a somewhat thick oil film.

  As can be seen from FIGS. 3 and 4, each scraper ring 19 includes a holder ring 21 seated in the corresponding annular groove 22 of the housing 17 and a set of two seats seated in the corresponding annular groove of the holder ring 21. The above-mentioned uniform scraper layer plates 23a and 23b are provided. In the present embodiment, two scraper layer plates 23 a and 23 b are provided for each holder ring 21. As a result, one of the scraper layer plates 23 a and 23 b functions as the first or last with respect to the moving direction D of the reciprocating piston rod 11. Of course, a set of three or more scraper layer plates may be provided on a common holder ring. Equally shaped scraper layer plates 23a, 23b are axially offset from each other and project radially on the corresponding radial inner surface of the holder ring 21, creating a scraper edge.

  The holder ring 21 and the scraper layer plates 23a, 23b have radial variability, and the holder ring 21 engages the scraper layer plates 23a, 23b with the piston rod 11, so Spring biased to a small diameter. The ring-shaped spring 24 is disposed in an annular groove 25 that opens to the outside of the holder ring 21. The thickness of the oil film 26 deposited on the outer surface of the piston rod 11 should be reduced by the scraper layer plates 23a and 23b.

  In the known arrangement according to FIG. 3, the scraper layer plates 23 a, 23 b are firmly seated in the radial direction in the corresponding grooves of the holder ring 21. The first scraper layer plate 23a, which is the rear layer plate in the moving direction D of the piston rod 11, scrapes off a layer with cylinder oil, so that the thickness of the oil film 26 is halved as indicated by d1 and d2. Decrease. A hydrodynamic pressure that balances the inward spring force of the ring-shaped spring 24 is generated in the gap between the scraping layer plate 23 a and the outer surface of the piston rod 11. As a result, the radial position of the holder ring 21 and the further respective layer plates, here the radial position of the second scraper layer plate 23b, are defined by the radial position of the first scraper layer plate 23a. The scraper layer plates 23a, 23b have the same shape and thereby have the same diameter, but the first scraper layer plate 23a reduces the oil film thickness in half, so that the next layer plate, here the second scraper The layer board 23b is separated from the surface of the remaining oil film, and therefore has no scraping effect.

  This negative result is overcome by the present invention by elastically seating at least the first scraper layer plate 23a in the corresponding annular groove of the holder ring 21 in the radial direction, as seen in FIG. In the illustrated embodiment, both scraper layer plates 23a, 23b are placed in corresponding grooves in the holder ring 21 by flexible elements 27 positioned between the groove bottom and the radial outer surface of the layer plates 23a, 23b. Elastically seated. By means of this flexible element 27, the corresponding layer plates 23a, 23b can be adjusted in the radial direction by a force acting in the radial direction. Accordingly, each scraper layer plate 23a, 23b can reach the oil film 26, whereby the thickness of the oil film 26 is reduced by about half as indicated by d1, d2, d3 in FIG. 4 by each layer plate 23a, 23b. Reduce to. The positive result is that the thickness of the oil film 26 is more reliably reduced, so that the amount of cylinder oil supplied into the crankcase 1 from the upper side to the lower side of the seal packing 15 by the piston rod 11 is relatively small. Is to decrease. Accordingly, the lossy harmful pollution that the system oil of the crankcase 1 is contaminated with the cylinder oil is substantially reduced.

  To construct the flexible element 27 described above, flexible padding is deposited in the corresponding annular groove of the holder ring 21 behind the corresponding scraper layer plates 23a, 23b. The flexible padding has a flexible cross-sectional design and / or may be made from a flexible material. In practice, known so-called O-rings can be inserted for multiple purposes. Of course, the individual flexible padding inlays in the groove allow other suitable cross-sectional profiles / shapes, as well as cavities, to allow compression to increase or decrease the radial movement of the laminate. Preferably, it should be combined with a suitably selected polymeric material having elastic properties. Alternatively, or in addition, an elastic layer made of a flexible material and / or designed with a flexible cross section can be provided on the outer periphery of the scraper layer plates 23a, 23b. When a rubber-like material is used, the elastic layer may be vulcanized on top. In the case of other materials, other bonding processes for integrating with the laminar plate may be, for example, crimping / elastic gripping, application of an adhesive, and the like.

  To avoid overflowing the scraping area with oil, the scraped oil or an oil mixture containing cylinder oil and combustion residues must flow out of the scraping area. For this purpose, the holder ring 21 is provided with at least one discharge outlet 28 opening in the region between the two scraper layer plates 23a, 23b. In the embodiment shown in FIG. 4, the holder ring 21 is further provided with at least one discharge groove 29 at least on the front side adjacent to the rear layer plate 23a, preferably on both front sides. Of course, it is also possible to provide two or more outlets and / or discharge grooves evenly arranged on the circumference of the holder ring 21. In order to allow the collected oil to flow out, the outlet 28 and the discharge groove 29 communicate with a drain line 30 shown in FIG. 2, which leads to an oil reservoir (not shown). The oil discharged by the discharge outlet 28 and the groove 29 enters the corresponding annular groove 22 of the housing 17, but in order to ensure a constant flow path without reducing the speed, each such groove 22 of the housing 17 is provided with a drain pipe. Connected to the path 30.

  In order to easily attach the scraper ring 19 around the piston rod 11 which is maintained in place through the collection chamber bottom 8 or the crankcase ceiling, it comprises a holder ring 21 and corresponding scraper layer plates 23a, 23b. The scraper ring 19 can be segmented in the circumferential direction. Thereby, the holder ring 21 and the scraper layer plates 23a and 23b are constituted by a set of more segment pieces. In the embodiment shown in FIG. 5, three segment sections are used. Therefore, here, three segment pieces 19a, 19b, 19c of 120 ° are provided. In order to avoid building a straight channel for scraping oil by the gap between the plurality of segment pieces 19a, 19b, 19c, as shown in FIG. 6, at least the segment pieces of the holder ring 21 have tongues 31 that overlap each other. Provided at both ends. This substantially reduces the free passage through the double chevron channel of the gap 32, especially when the scraper lamella is installed and used.

  In practice, the overlapping tongue region is blocked radially outward so that the gap 32 cannot function as a disturbing leak channel that impairs the drain as described above. For this purpose, as shown in FIG. 7, a cover element 33 that covers the gap 32 on the outside is provided. The cover element 33 can be designed as a thin cover plate or strip. In the embodiment shown in FIG. 7, the outer circumference of the holder ring 21 for a circular shape is flattened in the area of each section, and thus flattened in the area of each gap 32, as indicated by the flat portion 34. In this case, the configuration of the cover element 33 is designed to correspond to the ring part removed to receive the flat part 34, each defined on the outside of the flat part (34) and on the inside of the rotational circumference of the entire holder ring. Fill volume. Of course, the housing 17 may be divided so that it can be removed / attached while the piston rod is connected to both the lower crosshead and the piston of the upper cylinder.

  In the embodiment described above, the fluid scraped off in connection with the crosshead motor is cylinder lubricant and the associated rod is a piston rod. However, other uses, such as hydraulic cylinder piston assemblies, may be examples. In the described embodiment, a seal packing 15 with one or more scraping devices effectively separates the collection chamber 7 and the cylinder oil therein from the inner space of the crankcase 1 and the system oil therein. Should be able to. This separation operation occurs during the start of the piston rising stroke, passes through the lower edge of the cylinder liner 4 and blows a large amount of cylinder oil that would be contaminated with combustion residues directly to the piston rod 11. Can be facilitated when turning from the radial direction to at least approximately the axial direction.

  For this purpose, as shown in FIG. 2, a skirt 35 can be provided upstanding from the collection chamber bottom 8 and surrounding the piston rod 11. The skirt 35 shields the piston rod 11 from deposits of cylinder oil particles and combustion residues. In principle, a simple tubular structure that shields the piston rod 11 is sufficient. Preferably, a funnel-like or trumpet-like upper rim may be provided. In practice, the skirt 35 is preferably a split design for placement around the piston rod to which it is attached and can be attached to the upper flange of the housing 17 or, as shown in FIG. 18 may be attached to the upper front end.

  It is also useful in terms of assembly and maintenance if at least one of the elements of the scraping device according to the invention comprises at least one tag, preferably an RFID type tag, containing stored data that clearly authenticates said element or device I know from experience. Typically, the authentication data may also include manufacturing data, approval data, historical data, possible or planned future usage data, and the like.

  The above description of preferred embodiments does not limit the scope of the invention as defined in the claims.

Claims (25)

A device for scraping the circumferential surface of the rod to which a fluid has adhered, wherein the device is adapted to the rod dimensions, the rod being movable axially through the opening of the device, , Comprising at least two scraper layer plates (23a, 23b) of axially offset from each other and each of which is divided and individually variable in radial direction,
Each of the laminar plates (23a, 23b) is provided with an annular groove that opens radially inward, and projects in the radial direction on the radially inner surface to a common holder ring (21) that is also variable in the radial direction by a divided design. Each said layer board (23a, 23b) is provided,
Accordingly, in the apparatus that enables the spring bias adaptation in the radial direction with respect to the area where the holder ring is circumscribed by the spring configuration corresponding to the outer surface in the radial direction of the holder ring, each of the layer plates (23a, 23b) The apparatus is characterized in that it is elastically supported in the radial direction with respect to the groove bottom portion of the annular groove corresponding to each of the layer plates (23a, 23b).   2. A device according to claim 1, characterized in that at least a flexible padding (27) is seated on the bottom of the corresponding annular groove for elastically supporting the lamellae (23a, 23b).   Device according to claim 2, characterized in that the flexible padding (27) is constructed by a ring made of elastic material.   The device according to claim 3, wherein the elastic ring is an O-ring. A layer of elastic material is provided on at least the radially outer surface of the elastically supported scraper layer plates (23a, 23b), so that the layer plate can be moved further radially outward by an increased biasing force. The apparatus according to any one of claims 1 to 4, wherein: 5. A device according to claim 4, characterized in that the elastic ring is vulcanized on the radially outer peripheral surface of the scraper layer plate (23a, 23b). Each of the two scrapers lamellae (23a, 23b) at least two holders rings having (21), characterized in that provided in the common housing (17), any one of claims 1 to 6 The device described in 1. 8. The holder ring (21) according to any one of the preceding claims , characterized in that it comprises at least one discharge outlet (28) opening in the region between the two scraper layer plates (23a, 23b) . The apparatus according to item 1 . 9. The holder ring (21) according to any one of the preceding claims , characterized in that the holder ring (21) comprises at least one respective discharge groove (29) in the region of at least one axial outer surface. apparatus.   10. Device according to claim 9, characterized in that the holder ring (21) has a discharge groove (29) in the region of both axially outer surfaces. 11. Device according to any one of claims 8 to 10 , characterized in that each discharge outlet (28) and / or a discharge groove (29) can communicate with a drain line (30).   The holder ring (21) can be arranged in a corresponding radially inner ring groove (22) of the annular housing (17), and the ring groove (22) is connected to the drain line (30) The device according to claim 11, characterized in that it can be performed. The holder ring (21) and the layer plates (23a, 23b) are segmented circumferentially into several pairs of more pieces (19a, 19b, 19c), and at least the pieces of the holder ring are Device according to any one of claims 1 to 12 , characterized in that it is provided at both ends with overlapping tongues (31).   14. Device according to claim 13, characterized in that the region of the overlapping tongue (31) is sealed by a cover element (33) arranged on the radially outer surface of the holder ring (21).   The radially outer surface of the holder ring (21) has a flat portion (34) in the region of the overlapping tongue (31), and each corresponding cover element (33) is located outside the flat portion (34) and The device according to claim 14, wherein the device is provided so as to fill each volume defined inside the entire rotation peripheral surface of the holder ring. Said holder ring (21), characterized in that it comprises a radially outwardly open annular groove for receiving an annular spring (24) to build a corresponding spring arrangement (25), claims 1 to 15 The apparatus of any one of these . 17. A device according to any one of the preceding claims , characterized in that the majority of the holder ring (31) can be contained in a common annular housing (17).   The common annular housing (17), which can contain the majority of the holder ring (31), is a split design, allowing positioning around the rod without passing through the rod end The apparatus of claim 17.   2. An apparatus for scraping cylinder lubricant for a piston rod of a motor according to claim 1, wherein the scraped fluid is cylinder lubricant.   Device according to claim 19, characterized in that the rod is a piston rod (11) of a motor with a piston rod (11). 21. A device according to any one of the preceding claims , characterized in that at least one of the elements of the device comprises at least one tag comprising stored data that clearly defines the element or device. apparatus.   The apparatus according to claim 21, characterized in that the tag is of the RFID type. A crosshead type engine comprising a crankcase (1) and at least one cylinder (3), said cylinder (3) extending in a surrounding collection chamber (7); , A piston (5) disposed in the cylinder (3), and the piston (5) is connected to a corresponding crosshead (10) disposed in the crankcase (1) with a piston rod (11). ) And the piston rod (11) passes through a seal packing (15) arranged in a wall configuration between the collection chamber (7) and the crankcase (1), at least 1 Engine, characterized in that one of the seal packings (15) comprises at least one device according to any one of claims 1 to 22 .   For at least one piston rod (1), a skirt (35) is provided which stands upright from the bottom of the collection chamber (8) and which surrounds the corresponding piston rod (11) corresponding to at least one of the seal packings (15). 24. The engine of claim 23, wherein: The skirt (35) is attached to the upper flange of the housing (17) of the seal packing (15) or the upper front end of the socket (18) surrounding the housing (17) of the seal packing (15). The engine according to claim 24.

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