KR100252522B1 - A piston engine of the crosshead type - Google Patents

Abstract

The present invention relates to a crosshead piston engine, in which the crosshead includes two longitudinal guide surfaces (9,10) facing in the transverse outward direction of the engine and a central longitudinal auxiliary guide surface (28) in the longitudinal direction of the engine. It is guided by a guide member 8 in the form of an elongated beam comprising: The guide member 8 is disposed at the longitudinal center plane of the engine and is positioned at the center of the extension in the height direction of the engine rotatably journaled to the engine frame box 1, while the upper and lower ends of the guide member are posts. 21 can be fixedly adjustable in the transverse direction of the engine. The crosshead 29 has a U-shaped guide shoe 33 having mutually opposing support surfaces 37, 38, between which the guide member has a support surface 37, 38 with an outward guide of the guide. It may be received to slide along faces 9 and 10.

Description

Crosshead Piston Engine

1 is a cross-sectional view showing an embodiment of an engine frame box with a guide member according to the invention.

FIG. 2 is a cross sectional view showing the main support point of the guide member shown in FIG.

3 is a cross-sectional view showing the auxiliary support of the guide member shown in FIG.

4 is a side view showing the end of the guide member shown in FIG.

5 is a cross-sectional view showing an embodiment of a piston engine according to the present invention.

6 is a side view showing an embodiment of a guide shoe according to the present invention.

FIG. 7 is a detailed view showing the joint of the post and yoke shown in FIG.

* Explanation of symbols for main parts of the drawings

1: engine frame box 8: guide member

21: Holding 29: Cross Head

30: connecting rod 33: guide shoe

37,38: support surface 42: auxiliary support surface

According to the invention, a crosshead connecting the piston rod with the connecting rod is guided transversely to the engine by at least one guide shoe, which guide shoe is supported by the engine frame box and parallel to the longitudinal axis of the cylinder associated with the piston. A crosshead piston engine having at least one support surface that can slide along a corresponding guide surface of an extending guide member.

Prior art crosshead engines generally have two guide members, which guide members mutually at a distance at which the associated guide shoe on the crosshead can be placed in the middle of the engine between two opposing guide surfaces of the guide member. Facing in the lateral direction. An outward support surface is provided on one side of the guide shoe that can contact the inward guide surface on the associated guide member. The guide members are fixed on the transverse wall of the engine frame box between the pedestal and the cylinder part. The guide member is generally formed integrally with the transverse wall by integrally casting the transverse wall and the guide member, but is inclined such that the guide member is firmly welded to the transverse wall and extends outward from the free edge of the guide member to the transverse wall. It is more common to integrate the transverse walls in such a way that they are reinforced by stiffeners.

In the engine of the prior art, the production of the transverse wall of the engine frame box with the guide wall is time-consuming and expensive, because it is necessary to prevent the guide shoe from moving between the guide members. This is because the guide members must be manufactured to have a high degree of parallelism even during engine operation. In view of the fact that the guide members are firmly connected to the engine frame box, the guide members are loaded with the compression force of the fixing bolts on the one hand, or on the other hand, when the engine load changes, especially when the engine is stopped for a long time. Torsion and bending occur when subjected to load by thermal loading, which occurs when starting up afterwards. Deformation of the guide member causes the guide shoe to be unevenly supported on the guide surface, thereby causing the guide shoe to be locally heated to expand. In the worst case, this phenomenon can prevent the guide shoe from moving between the guide surfaces due to the lateral expansion of the guide shoe.

When the engine is installed on a ship, the movement of the ship generates a small twist of the transverse wall and the guide members, causing both the guide shoe and the guide member to be severely worn out.

It is an object of the present invention to provide a piston engine with reduced risk of damage or wear of the guide member or guide shoe.

For this purpose, a piston engine according to the invention is characterized in that the guide member is arranged at the longitudinal center plane of the engine, and the guide surface of the guide member is directed at least partially outwardly in the transverse direction of the engine so that the associated supporting edge of the guide shoe is above. And at least partially disposed on the side of the guide surface facing away from the central surface.

Placing the guide member on the center face of the engine allows the guide member to avoid the effects of torsion on the transverse wall because the guide surface moves less with respect to the determined deformation of the transverse wall. Since the guide shoe is disposed on the outside of the guide member or is located around the guide member, due to the heating of the guide shoe and consequently the expansion of the guide shoe, the guide surface is moved slightly outward in the direction away from the guide surface. The holding force around the member is reduced.

Since the guide member can be properly supported on the engine frame box at the longitudinal center plane of the engine, the twist of the transverse wall of the engine frame box relative to the center plane will only move the guide member to a minimum.

The twisting of the guide surface due to the temperature difference between the guide member and the engine frame box is such that the guide member disposed at one point, preferably in the center of the planar extension in the height direction of the engine, pivots to the engine frame box. And, the guide member can be largely removed by being able to fix in the transverse direction of the engine at its upper and lower ends. Since the guide member is not rigidly coupled to the engine frame box, the single point hinge journal cannot transmit strain due to temperature, and the transverse fixation of the engine allows the guide member to be hotter than the transverse wall of the engine frame box during engine operation. The longitudinal expansion by the rise of the temperature of the guide member in the height direction of the engine.

The possibility of free expansion of the guide member with respect to the transverse wall occurs irrespective of the position of the fulcrum, however, the point is arranged in the center of the guide member, thereby uniformly making possible longitudinal expansion in the upward and downward directions. It is preferable to distribute.

The guide member can be easily mounted in that both the top and the bottom of the guide member can be fixedly adjustable in the transverse direction of the engine, and it is also ensured that the guide surface extends parallel to the longitudinal axis of the associated cylinder. The reason is that by arranging the upper end and the lower end of the guide member with respect to the suspension point during simultaneous pivoting of the guide member, the final alignment of the guide member can be made in a simple manner after the engine frame box is deformed by tightening the fastening bolts. Because there is.

In a particularly simple embodiment, the guide member may be an elongated beam having two longitudinal guide surfaces transversely outwardly of the engine and a central longitudinal auxiliary guideface longitudinally of the engine. . The beam is a separate part with a relatively small size, which can be produced by casting, and thus can be easily final machined to precise dimensions prior to mounting on the engine. Compared to a prior art engine with two independent guide members for supporting each guide shoe, it can be quite simple in that only one guide member with two guide surfaces is mounted, which is the longitudinal axis of the cylinder. This is particularly advantageous because the alignment of the guide member with respect to must be carried out very carefully.

The present invention is also characterized in that the guide shoes have two support surfaces spaced apart from each other, and a guide member is received between the support surfaces so that the support surfaces slide along the guide surface oriented outwardly of the guide member. It relates to a piston engine of the above-described form. Since the heat normally generated between the guide surface and the support surfaces is absorbed by both the guide member and the guide shoe, the guide shoe of a considerably shorter dimension in the moving direction will become significantly higher than the guide member. This temperature difference also increases because the guide shoes alternately slide from one guide face to the other. In view of the fact that the guide member is disposed between the supporting surfaces, even if the guide shoe becomes hot, there is no risk of freely thermally expanding and moving in the transverse direction of the engine.

The guide shoe preferably has at least one auxiliary support surface which is disposed in the center of the guide shoe in the transverse direction and in the longitudinal direction of the engine. The auxiliary support surface guides the guide shoe, thereby guiding the connecting rod and the piston rod in the longitudinal direction of the engine. Since the support surface according to the invention is centered on the guide shoe, the longitudinal guide force of the engine does not exert any tilting action on the guide shoe.

One embodiment of the present invention will now be described in detail with reference to the schematic drawings.

1 shows a cross-sectional view of an engine frame box 1 for a large low speed diesel engine for use as a propulsion engine of a ship. The engine frame box comprises a longitudinal lower plate 4 arranged horizontally for connection with the engine pedestal, a longitudinal upper longitudinal top plate 5 and a lower plate 4 arranged horizontally for connection with the cylinder part. And longitudinal side members (2, 3) for rigidly connecting the upper plate (5). The cylinder part, the engine frame box 1 and the pedestal are fastened to each other by the fixing bolts 6 to form a single unit. The engine frame box has a reinforcing transverse wall 7 that absorbs pressure from the fixing bolt 6 and has a guide member 8 for disposing the crosshead in the transverse direction of the engine.

The guide member 8 takes the form of an elongated cast beam having two longitudinal sides machined in parallel to each other such that the guide member is mounted on the transverse wall and laterally spaced outwardly towards the transverse direction of the engine. do. Outward sides act as guide surfaces 9 and 10 of the associated guide shoe.

At the main support point A, the pivot 11 is pressed into the pivot hole 12 of the guide member 8 and is firmly engaged, as shown in FIG. The pivot 11 projects from the rear side of the guide member having a planar portion 13 projecting in the area around the pin, the planar portion 13 being mounted for receiving the projecting end of the pivot 11. By contacting on the corresponding plane 14 formed in the transverse wall 7 with respect to the hole 15, the guide member is journalized in the transverse wall 7 so as to be pivotable with respect to the pivot 11. Around the mounting hole 15 there are a number of through bores 16 opposite the associated bores 17 of the guide member. The through bores 16 have a diameter somewhat larger than the bore 17 such that a fastening means, such as a bolt 18 inserted into the bore 17, has a constant clearance with respect to the through bore 16. Allow constant rotation of the guide member relative to

In order to align the guide member in the longitudinal direction of the engine, the guide member is spaced from one side of the main support point A and on one side of the support point, and is in contact with the plane 14 ′ formed in the transverse wall 7. It further comprises two auxiliary support points B having 13 '.

As shown in Figs. 1 and 4, the guide member has a protruding fork 19 having transversely extending grooves 20 into which upper and lower ends thereof can be inserted. Have 7 shows how the ends of the support struts are mounted to the journaled yoke 22 through the lateral wall. Each extreme of the support struts consists of a threaded spindle 23 which is fastened to the yoke 22 by means of a coupling piece 24 and a screw nut 25 on one side of the yoke. The region of the support strut arranged around the fork 19 is formed as a threaded rod having a coupling piece 26 and an adjusting screw nut 27 on one side of the fork 19.

The guide member can be mounted in the engine after welding of the engine frame box 1 has been carried out, which enables the guide member to be finally machined before mounting to the engine. In the mounting operation, the guide member is suspended in the transverse wall 7 by first passing the pivot 11 into the mounting hole 15. When in the guide member on one side of the transverse wall, the guide member can be advantageously mounted at the same time, as shown in FIG. 5, because a threaded spindle or continuous bolt 18 can be used. Two guide members associated with the same cylinder are aligned in the longitudinal direction of the engine with respect to each other by inserting appropriate shims (not shown) between the planes 14 and 14 'and the planar portions 13 and 13'. do. This shim must be made of a gamma material, for example a copper-zinc alloy, which acts as a kind of slide bearing and facilitates the thermal expansion of the guide member with respect to the lateral wall 7. The final alignment in the transverse direction of the guide member to be completely parallel to the longitudinal axis of the cylinder concerned is achieved by adjusting the screw nut 27 in the support strut 21. Finally, the spindle or bolt 18 is transversely displaced at a distance from the center surface of the engine to absorb the torque load from the guide shoe and provide space for the centrally arranged longitudinal auxiliary guide surface 28. Tightened, the guide face ensures the centering of the crosshead, thus ensuring the centering of the piston rod and connecting rod in the longitudinal direction of the engine.

As the support struts 21 have a sufficiently large length, the longitudinal expansion of the guide member is ensured, and the shank portion of the struts compressed in the front of the engine during the downward actuating stroke of the piston is larger in diameter than the rest of the shank. Has

5 and 6 show a crosshead 29 having an outer bearing portion connected to the connecting rod 30 and a crosshead pin 31 connected to a piston rod (not shown). The crosshead pin 31 has two cylindrical pins 32 which protrude in the longitudinal direction and carry the guide shoe 33. In order to reduce the extension of the crosshead in the longitudinal direction of the engine, the guide shoes 33 pass into the associated grooves 34 of the crosshead pins.

The guide shoe 33 is U-shaped and engages with the associated guide member 8. A strip-shaped steel member coated with a bearing metal such as white metal is fixed on the inner side of each U-shaped branch pipe by bolts 35. Removably fixed strips allow replacement of the worn bearing surface, but may also provide an implanted white metal region in the guide shoe 33. The sides of the mutually opposing strips 36 constitute support surfaces 37, 38 for the guide shoes. The support surface on the guide member and the guide surfaces 9 and 10 slide alternately with each other during operation of the engine and communicate with the oil inlet port of the cylindrical pin 32 of the crosshead pin through the channel 40. Lubricated by 39).

The strip 41, which is covered with bearing metal and has an auxiliary support surface 42 facing in the longitudinal direction of the engine, is disposed centrally at the top and bottom of the guide shoe 33. While the crosshead is moving in the longitudinal direction of the guide member, the auxiliary support surface 42 slides along the auxiliary guide surface 28, thereby arranging the crosshead in the longitudinal direction of the engine. In view of the fact that the auxiliary support surface 42 is arranged on the center surface of the engine, the guide force acting on the crosshead in the longitudinal direction of the engine cannot exert any tilting action on the crosshead. Of course, only one strip 41 may be used, but the use of two members arranged at the maximum possible distance from the centerline of the crosshead may provide the smallest possible guide force. The strip 41 is fixed to the groove of the guide shoe by means of a bolt 43 with an associated joining member. The auxiliary support surface 42 lubricates through the oil channel 44.

As described above, when the guide member is placed in the center, the guard surface and the support surface are only minimally affected by the twisting in the transverse wall 7 during operation of the engine, and when the guide member is mounted to the engine, Aligning the plane after tightening the bolts does not complicate the compensation for possible deformation of the transverse wall 7.

The guide member may be shaped like a cylindrical face, for example, and the cylindrical outer face of the cylindrical face may constitute a single guide face for the guide shoe around the guide member by at least one circular segmented support surface, The invention is not limited to the use of a guide member having two opposing guide surfaces. This embodiment can also be used for smaller engines.

Claims (9)

A crosshead 29 connecting the piston rod with the connecting rod 30 is guided in the transverse direction of the engine by at least one guide shoe 33, which is guided by the engine frame box 1. In a crosshead piston engine having at least one support surface 37, 38 that is supported and can slide along a corresponding guide surface 9, 10 of the guide member extending parallel to the longitudinal axis of the cylinder associated with the piston. , The guide member 8 is arranged on the longitudinal center surface of the engine and the guide surfaces 9, 10 of the guide member are directed at least partially outward in the transverse direction of the engine, thereby relieving the associated of the guide shoe 33. Cross-head piston engine, characterized in that the support surface (37,38) is at least partially disposed on the side of the guide surface facing away from the central surface. 2. The crosshead piston engine according to claim 1, wherein the guide member is supported on the engine frame box in the longitudinal center plane of the engine. 3. The guide member (8) according to claim 2, wherein a guide member (8) arranged in the center of the planar extension in the height direction of the engine is pivotably journaled to the engine frame box (1), the guide member being at the top and bottom of the engine. Crosshead type piston engine, characterized in that can be fixed in the transverse direction. 4. An upper end and a lower end of the guide member 8 can be fixed individually adjustable in the transverse direction of the engine, and the guide member 8 can freely move heat in the height direction of the engine. Crosshead piston engine, characterized in that. 2. The guide member (8) according to claim 1, wherein the guide member (8) is thin and has two guide surfaces (9, 10) facing outward in the transverse direction of the engine and a central longitudinal auxiliary guide surface (28) in the longitudinal direction of the engine. A crosshead piston engine characterized by being a long beam. 6. The two guide members 8 according to claim 3, arranged on one side of the transverse wall 7 of the engine frame box, are pivoted onto at least one pivot 11 of the transverse wall. A crosshead piston engine characterized by being mutually assembled by a bolt (18), which is possibly journaled and is a fixing means passing through a transverse wall having a gap. 7. A crosshead piston engine according to claim 6, wherein a shim of a gamma material such as a copper-zinc alloy is inserted between the guide member (8) and the transverse wall (7). A crosshead 29 connecting the piston rod with the connecting rod 30 is guided in the transverse direction of the engine by at least one guide shoe 33, which is guided by the engine frame box 1. In a crosshead piston engine having at least one support surface 37, 38 that is supported and can slide along a corresponding guide surface 9, 10 of the guide member extending parallel to the longitudinal axis of the cylinder associated with the piston. , The guide shoe 33 has two support surfaces 37 and 38 spaced apart from each other and a guide member 8 is received between the support surfaces such that the support surfaces 37 and 38 are outward of the guide member. And a slide along a guide surface (9,10) oriented in the direction of the crosshead. 9. The crosshead piston engine according to claim 8, wherein the guide shoe (33) has at least one auxiliary support surface (42) which is arranged in the longitudinal direction of the engine and in the transverse direction at the center of the guide shoe.