JP2007211786A - Engine frame structure - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an improved design concerning stay bolts with regard to an engine frame structure of a cross head type two-stroke diesel engine of welding manufacture. <P>SOLUTION: In a cross head type internal combustion engine equipped with: a base plate (2) having a main bearing (3) for a crank shaft (4); and an engine frame (9) mounted to a base plate fabricated by welding, the engine frame has: a top plate (11); two opposing outside walls (10); horizontal stiffness supplementary member which extends in a horizontal direction between each cross head (8) between outside walls, and also extends upwards to the top plate while supporting a guide surface (14) of the cross head; and a plurality of the stay bolts (19) clamping the base plate and the engine frame. The stay bolts are disposed inside a plane of the horizontal stiffness supplementary member with a horizontal stiffness supplementary member having a structure branching to two branch state reinforcing walls (17') which are connected with a rear side of the guide surface. By this arrangement, inside the plane of the horizontal stiffness supplementary member, hollows (18') which take in stay bolts are formed. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a cross-head type two-stroke diesel engine having an engine frame manufactured by welding, and more particularly, to a compact but sturdy engine frame structure.

Danish Patent Application No. 1406/92 discloses a crosshead type two-stroke diesel engine having an engine frame made by welding mounted on a base plate. The engine frame has a top plate in which perforations for receiving a cylinder liner are formed, and an intermediate bottom plate that divides the engine frame into an upper cylinder frame portion and a lower crankcase frame portion. Two opposing vertical outer walls extend from the bottom of the engine frame to the top plate. Lateral stiffeners adjacent to each crosshead on two longitudinally opposite sides of the engine frame extend laterally between the longitudinal outer walls and then extend upward to the intermediate bottom plate. For each crosshead, four guide surfaces extend upward to the intermediate bottom plate. Two of the four guide surfaces are supported by a lateral stiffener on one side of the corresponding crosshead, and the remaining two guide surfaces are supported by a lateral stiffener on the opposite side of the corresponding crosshead. This engine frame structure is an improvement over the normal structure having a welded crankcase frame with a cast cylinder frame clamped.
Danish Patent Application No. 1406/92

  In light of the above background, an object of the present invention is to provide an engine as described above, which is robust and strong and easy to assemble while the engine frame is compact. The purpose is that the lateral stiffener and the guide surface extend to the top plate, and the upper part of the guide surface supported by the lateral stiffener on one side of the relevant crosshead is supported by the lateral stiffener on the opposite side of the relevant crosshead. This is accomplished by providing an engine connected to the top of the guide surface.

  By connecting the upper portions of the guide surfaces to each other, the strength and rigidity of the engine frame are significantly improved. The longitudinal stiffeners thus formed have not been known in the past. Furthermore, by extending the guide surface and the lateral stiffener to the top plate, the engine frame can be easily assembled and the strength can be improved. Longitudinal stiffeners can significantly improve the vertical stiffness of the engine frame.

  By extending the upper portions of the adjacent guide surfaces into the plane of the guide surface and connecting them to each other, the adjacent guide surfaces can be formed as a single plate. By performing this operation for all the guide surfaces located on the same side of the cross head, a single plate structure extending in the vertical direction can be formed.

  The notch effect can be reduced by making the connection between adjacent guide surfaces arched.

  The upper end of the plate structure extending in the longitudinal direction of the interconnected guide surfaces can be connected to the top plate substantially over the entire length of the engine.

  Each cylinder may be provided with a bottom plate extending between the upper portions of the guide surfaces. The bottom plate is provided with a through hole for accommodating the piston rod. The cavity formed in this way is for accommodating the lower part of the cylinder liner having the scavenging port.

  A scavenging receptor can be formed in the engine frame. By incorporating the scavenging air received in the engine frame, the size of the engine, particularly the height and width of the engine, can be significantly reduced. Furthermore, the overall structure is lighter and stronger. The scavenging receptor is preferably defined by an interconnected upper portion of the guide surface on one side. The opposite side of the scavenging receptor is preferably defined by one longitudinal side wall. In the downward direction, the scavenging receiver is preferably defined by a receiver bottom plate extending between the top of the interconnected guide surfaces and one longitudinal outer wall of the engine frame. In order to obtain the volume required for the scavenging receiver without changing the height or width of the engine, it is preferable to place the bottom plate of the receiver as low as possible.

  For each cylinder, 1 is placed on the interconnected upper portion of the guide surface that forms the wall of the scavenging receptor to allow the scavenging to escape from the scavenging receptor and to be introduced into the cavity where the lower part of the cylinder liner with the scavenging port projects. It is also possible to provide one or more openings.

  An opening may be provided in the portion of the lateral stiffener that extends into the scavenging receptacle to allow scavenging to pass from one cylinder to the next.

  A camshaft can be arranged in the engine frame, and the lateral stiffener is preferably provided with an opening and a support for the camshaft.

  A support plate for transmitting the compression force from the cylinder liner to the top plate can be disposed between the cylinder liner and the top plate.

  It is a further object of the present invention to provide an engine as described above that has an improved design with respect to retaining bolts. The purpose is to extend laterally between a base plate with a main bearing for the crankshaft, a welded engine frame with a top plate attached to the base plate, and a vertical outer wall, and further up to the top plate This can be achieved by providing a crosshead type two-stroke internal combustion engine with two opposing longitudinal outer walls extending and a lateral stiffener between the crossheads. The lateral stiffener supports a guide surface for the crosshead. The base plate and the engine frame are clamped by a plurality of retaining bolts, the retaining bolts are arranged in the plane of the lateral stiffener, and a cavity for accommodating the retaining bolts in the plane of the lateral stiffening body , By branching to two branch-shaped reinforcing walls connected to the back side of the corresponding guide surface.

  Accordingly, a robust yet compact engine frame that is easy to assemble with a stable cavity for receiving the retaining bolt is provided. The engine frame according to the present invention requires half the necessary bolts compared to the engine frame disclosed in Danish Patent Application No. 1406/92, so that the bolts are manufactured, the top plate is provided with holes, It is possible to reduce the cost required to provide a hole with a screw in the plate. Furthermore, the end of the reinforcing wall welded to the guide surface can be arranged near the plane of the lateral stiffener. In the reinforcing wall according to Danish Patent Application No. 1406/92, considering that it is necessary to perform a complicated welding process at the bottom of the engine frame due to the recess for receiving the stud / bolt for the main bearing, This feature has significant advantages. According to the invention, this recess and the complicated welding process required thereby can be avoided.

  Suspend the lateral plate of the lateral stiffener in front of the retaining bolt, join the curved surface of the U-shaped plate to the interrupted end, and join the end of the U-shaped plate to the back side of the corresponding guide surface Can branch the lateral stiffening body.

  In addition, the transverse plate of the lateral stiffener is interrupted in front of the retaining bolt, and two bent or flat reinforcing walls are joined to the lateral stiffener preferably at the interrupted end so that the respective ends expand, The lateral stiffener can be branched by joining the opposite side of the reinforcing wall to the back side of the corresponding guide surface.

  Connect the corresponding lateral stiffener from the plane to the bent side of the side stiffener with one end extending from the plane of the side stiffener, and bend the flat side from the plane. It is also possible to connect both free ends of the lateral stiffeners to the back side of the corresponding guide surface.

  In order to save space and facilitate the welding process between the guide surface and the lateral stiffener, the two reinforcing walls of the lateral stiffener bifurcation are formed by a plate around the perimeter of the corresponding retaining bolt It may be a thing.

  A part of the retaining bolt preferably extends into a cavity formed between the guide surface and the two reinforcing walls of the bifurcation of the lateral stiffener.

  Further objects, features and advantages of the engine according to the present invention will become apparent from the following detailed description.

  In the following detailed description, the present invention will be described more specifically by means of preferred embodiments.

  1 and 2 show a large multi-cylinder two-stroke turbocharged diesel engine 1 constructed from a base plate 2 on which a crankshaft 4 is installed via a main bearing 3. The number of cylinders of this type of engine is usually 4-12. For convenience, only a cross-sectional view of one cylinder is shown. The base plate 2 consists of a welded stringer and a welded crossgirder having a cast steel bearing support.

  The piston 5 of the engine 1 is connected to the crankshaft 4 via a piston rod 6 connected to a connection rod 7 by a crosshead 8.

  An engine frame 9 designed to be welded is attached to the base plate 2. An engine frame 9 is provided with a top plate 11 that holds an outer wall 10 that extends vertically and a cylinder liner 12. Here, the top plate 11 is provided with a number of through-holes equal to the number of cylinders of the engine in a row, and a cylinder liner 12 is accommodated in each of the holes. A lower portion of the cylinder liner 12 provided with the scavenging port extends to the engine frame 9.

  The engine frame 9 has a lateral stiffening body 13 formed of a lateral plate that extends from the lower portion of the engine frame 9 to the top plate 11 and interconnects the outer walls 10 between the cylinders. The lateral stiffener 13 and the outer wall 10 are joined by welding over the entire length of the contact portion with the top plate 11. Since the lateral stiffener 13 extends between the opposing outer walls 10, high lateral rigidity is imparted to the engine frame box.

  Referring to FIG. 3, a vertically extending guide surface 14 for receiving a lateral force acting on the crosshead 8 via the guide shoe 15 is installed on the lateral stiffener 13 by welding or the like, for example. . In the middle of the horizontal stiffening body 13, two guide surfaces 14 are arranged opposite to each other in the lateral direction, and a cross-head guide shoe 15 is provided therebetween. Since one lateral stiffener 13 is provided on each side of the crosshead 8, there are four guide surfaces 14 in each crosshead. Two of the four guide surfaces 14 are installed on the lateral stiffener 13 on one side of the corresponding crosshead 8, and the remaining two guide surfaces 14 are installed on the lateral stiffener 13 on the opposite side of the crosshead 8. The guide surface 14 extends upward and reaches the top plate 11. An upper portion 16 is provided to connect the guide surfaces 14 to each other in the region above the engine frame. Therefore, the upper part of the guide surface 14 installed on the lateral stiffener 13 on one side of the crosshead is connected to the guide surface 14 installed on the lateral stiffener on the opposite side of the crosshead 8. According to a preferred embodiment, the upper portion 16 is a single through plate that spans the entire length of the engine.

  As illustrated, the connection between the upper portions of the guide surfaces 14 can be achieved by forming the two guide surfaces 14 from a single plate. However, other methods for interconnecting the two guide surfaces 14 facing in the vertical direction are conceivable.

  As shown most clearly in FIG. 4, since the upper portions 16 of the guide surfaces 14 of all the cylinders are interconnected, the upper portion 16 of the guide surfaces 14 has a through plate wall that increases the longitudinal rigidity of the engine frame 9. Forming.

  The back side of each guide surface 14 is supported by a vertically extending reinforcing wall 17 that connects the guide surface 14 to the lateral stiffener 13. As shown in the drawing, the reinforcing wall 17 may be made of a flat plate material that forms an acute angle with the lateral stiffener 13, but a horizontal semicircular or quarter-elliptical shape may be used instead of the flat reinforcing wall 17. In that case, the reinforcing wall 17 ′ extends substantially perpendicular to the lateral stiffener 13. The guide surface 14, the reinforcing wall 17 and the lateral stiffener 13 form a cavity 18 with high torsional rigidity.

  The engine frame 9 and the base plate 2 are clamped to each other by a plurality of pairs of retaining bolts 19 arranged close to each other. The lower end of the retaining bolt 19 is fixed to the upper screw hole of the base plate 2 and is pulled by the nut 20 on the top plate 11. Between the top plate 11 and the bottom of the engine frame 9, the bolts extend into the cavity 18, so that they function as cylinders for the bolts. The hollow profile provides the engine frame box with the necessary rigidity to withstand the large variable forces transmitted by the piston 5 to the frame box when the engine 1 is running.

  A support plate 21 that transmits a compression force from the cylinder liner 12 to the top plate 11 is provided between the cylinder liner 12 and the top plate 11 to reduce the bending moment applied to the top plate 11. By using the support plate 21, the top plate 11 can be designed to be lighter.

  A substantially square bottom plate 22 is welded in the horizontal direction between the top 16 of the interconnecting guide surfaces 14 facing in the lateral direction and between the two adjacent lateral stiffeners 13. A circular flange 23 for receiving a packing box (not shown) for guiding and sealing the piston rod 6 is welded to a corresponding opening in the center of the bottom plate 22. The bottom plate 22 can be provided with a slight inclination (not shown) in order to facilitate the waste of the liquid accumulated on the bottom plate. Moreover, in order to raise the rigidity of the baseplate 22, it can be set as a curved surface (not shown), and the joining to the upper part 16 can be performed by bolting instead of welding. Thus, the lower part of the cylinder liner 12 having the scavenging port protrudes into the cavity formed between the bottom plate 22 and the top plate 11.

  A scavenging receptor 24 is formed in the engine frame 9. The wall that defines the scavenging receptor is one of the interconnected upper portions 16 of one outer wall 10 and guide surface 14. The bottom of the scavenging receiver is formed by a receiver bottom plate 25 welded between the interconnected top 16 of the guide surface 14 and the one outer wall 10. The bottom plate 22 can be provided with a slight inclination (not shown) in order to facilitate the waste of the liquid accumulated on the bottom plate. The upper part of the scavenging receiver is formed by an upper plate 26 having a curved surface welded between the outer wall 10 and the top plate 11. A portion of the interconnected upper portion 16 of the guide surface 14 that forms the wall that defines the scavenging receptacle 24 is an opening through which the scavenging air can escape from the scavenging receptacle 24 and be introduced into the cavity from which the lower portion of the cylinder liner 12 projects. 27 is provided. A portion of the lateral stiffener 13 that extends into the scavenging receptacle 24 is provided with an opening 28 for passing scavenging from one cylinder to another.

  In order to obtain the required volume for the scavenging receptacle 24 without changing the width or height of the engine frame 9, the receptacle bottom plate 25 is set as low as possible. As shown by the dashed line 10 ′ in FIG. 2, the outer wall 10 may bulge around the scavenging receptor 24 in order to increase the volume of the receptor.

  The cam shaft 29 is disposed in the engine frame 9 on the opposite side of the scavenging receiver 24. On this side of the engine frame 9, the lateral stiffener 13 has an opening for the camshaft 29 and a support portion.

  FIG. 5 is a partial cross-sectional view showing a second embodiment of the present invention having a different outline structure for receiving the retaining bolt. In this embodiment, the engine frame may be a crankcase frame having a separate cylinder frame (not shown), and the scavenging receiver and camshaft need not be formed in the engine frame.

  The engine frame produced by welding has two opposing outer walls 10 and a lateral stiffener 13 adjacent to the longitudinally opposite crossheads 8 on each side. The horizontal stiffener 13 extends upward to a top plate (not shown). Further, the lateral stiffener 13 extends from one outer wall 10 to the other outer wall 10 in the lateral direction, but is installed so that the guide surface 14 divides the lateral stiffener 13 in the middle thereof. Each crosshead 8 is supported by four guide surfaces 14. The guide surface 14 extends from the bottom of the engine frame 9 to the top plate. Two of the four guide surfaces 14 are indicated by a lateral stiffener 13 on one side of the corresponding crosshead 8 and the remaining two guide surfaces 14 are supported by a lateral stiffener 13 on the opposite side of the corresponding crosshead 8. .

  The engine frame 9 and the base plate 2 are clamped by a retaining bolt 19. The reserve bolt 19 is disposed in the plane of the lateral stiffener 13. By branching the horizontal stiffener 13 to the two reinforcing walls 17 ′ immediately before the retaining bolt 19, a cavity 18 ′ for accommodating the retaining bolt 19 is formed. The curved portion of the U-shaped plate is joined to the end of the horizontal stiffener by, for example, welding. The free end of the U-shaped reinforcing wall 17 ′ is welded to the back side of the corresponding guide surface 14. Therefore, a stable cavity 18 ′ that can accommodate the retaining bolt 19 is formed. The two reinforcing walls 17 ′ of the bifurcation can be arranged closer to the flat part of the lateral stiffener 13 than the corresponding reinforcing wall according to the prior art. Therefore, it is not necessary to provide a recess at the bottom of the reinforcing wall for making a space for the main bearing stud / bolt.

  FIG. 6 shows a first modification of the second embodiment of the present invention. The lateral stiffening body 13 is branched by bending the lateral stiffening body before the retaining bolt 19. One end of the reinforcing wall 17 ′ is welded to the curved surface portion of the horizontal stiffener 13 in a direction that branches in the opposite direction from the plane of the horizontal stiffener 13. The opposite side of the reinforcing wall 17 ′ and the free end of the lateral stiffener 13 are both welded to the back side of the corresponding guide surface 14. The retaining bolt 19 is inserted into the cavity 18 ′ thus formed.

  FIG. 7 shows a second modification of the second embodiment of the present invention. The lateral stiffening body 13 is branched by being interrupted before the stand bolt 19. One end of each of the two reinforcing walls 17 ′ is welded to the lateral stiffener 13 in a branching direction, preferably to an interrupted portion of the lateral stiffener 13. The opposite side of the reinforcing wall 17 ′ is welded to the back side of the corresponding guide surface 14. The retaining bolt 19 is inserted into the cavity 18 ′ thus formed.

  The two reinforcing walls 17 ′ at the branch portion of the horizontal stiffener 13 can be formed by a plate (not shown, similar to the shape of FIG. 5) that bends around the corresponding retaining bolt 19.

  FIG. 8 shows a side view of guide surface 14 and its interconnected top 16 according to a further embodiment of the present invention. The upper part 16 and the guide surface 14 are made from a single steel plate. Due to the transition between the guide surface 14 and the upper part 16, the overall height of the structure is low compared to the arched embodiment described above. The rounded transition between the guide surface and the interconnected top 16 can reduce the notch effect and reduce the peak stress at the transition.

  FIG. 9 shows a guide surface 14 and its interconnected top 16 according to a further embodiment of the invention. In this embodiment, the upper part interconnected with the guide surface 14 is made from different steel plates joined by welding.

  FIG. 10 is a side view showing guide surface 14 and its interconnected top 16 according to a further embodiment of the present invention. In this embodiment, the upper part interconnected with the guide surface 14 is formed by individual steel plates joined by welding. The arched recess in the upper portion 16 forms a transition having a roundness between the guide surface 14 and the interconnected upper portion 16 for reducing stress as described above.

  FIG. 11 is a side view showing a guide surface 14 and its interconnected upper portion 16 according to a further embodiment of the present invention. In this embodiment, the guide surface 14 and each upper part 16 are formed by different steel plates joined by welding.

  Here, although the form for implementing this invention is mentioned as an example, the detail is an illustration to the last, and if it is those skilled in the art, the change of the grade which does not deviate from the technical scope of this invention can be performed. Please understand that this is possible.

  Accordingly, while preferred embodiments of the apparatus and method according to the present invention have been described in view of the developed background, they are merely illustrative of the principles of the present invention. Other embodiments and configurations are possible without departing from the scope of the appended claims.

FIG. 1 is a partially cutaway perspective view showing a preferred embodiment of an engine according to the present invention. FIG. 2 is a cross-sectional view showing the engine of FIG. FIG. 3 is a cross-sectional view of the engine taken along line III-III in FIG. 4 is a cross-sectional view of the engine taken along line IV-IV in FIG. FIG. 5 is a cross-sectional view corresponding to FIG. 3 showing a second embodiment of the engine according to the present invention. FIG. 6 is a sectional view corresponding to FIG. 5 showing a first variant of the second embodiment of the engine according to the invention. FIG. 7 is a cross-sectional view corresponding to FIG. 6 showing a second modification of the second embodiment of the engine according to the present invention. FIG. 8 is a side view of a connection support surface according to a further embodiment. FIG. 9 is a side view of a connection support surface according to a further embodiment. FIG. 10 is a side view of a connection support surface according to a further embodiment. FIG. 11 is a side view of a connection support surface according to a further embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Engine 2 Base plate 3 Main bearing 4 Crankshaft 5 Piston 6 Piston rod 7 Connecting rod 8 Crosshead 9 Engine frame 10 Outer wall 11 Top plate 12 Cylinder liner 13 Horizontal stiffener 14 Guide surface 15 Guide shoe 16 Upper part 17 of guide surface Reinforcement plate 17 'Reinforcement plate (branch)
18 Cavity 18 'Cavity 19 Retaining bolt 20 Nut 21 Support plate 22 Bottom plate 23 Circular flange (through hole)
24 Scavenging Receptor 25 Receptor Bottom Plate 26 Top Plate 27 Opening 28 Opening 29 Cam Shaft

Claims (6)

A crosshead type two stroke comprising a base plate (2) having a main bearing (3) for a crankshaft (4), and an engine frame (9) manufactured by welding attached to the base plate (2). An internal combustion engine,
The engine frame is
・ A top plate (11),
Two opposing outer walls (10);
A lateral stiffener (13) between each crosshead (8) extending laterally between the outer walls (10) and extending upward to the top plate (11), said crosshead (8); ) A lateral stiffening body (13) for supporting the guide surface (14) of
A plurality of retaining bolts (19) for clamping the base plate (2) and the engine frame (9);
Two branch-shaped reinforcing walls in which the retaining bolt (19) is arranged in the plane of the lateral stiffener (13) and the lateral stiffener (13) is connected to the back side of the guide surface (14) A two-stroke internal combustion engine characterized in that a cavity (18 ') for accommodating the retaining bolt is formed in the plane of the lateral stiffening body (13) by providing a structure branched to (17'). Engine engine.   The horizontal plate of the horizontal stiffener (13) is interrupted before the retaining bolt (19), the curved surface portion of the U-shaped plate is connected to the interrupted end, and the end of the U-shaped plate is connected to the end of the U-shaped plate. The two-stroke internal combustion engine according to claim 1, characterized in that the lateral stiffening body (13) is branched by being connected to the back side of the guide surface (14).   Interrupting the transverse plate of the lateral stiffener (13) before the retaining bolt (19), joining one end of each of two curved or flat reinforcing walls (17 ') to the interruption; The lateral stiffener (13) is branched by joining the other end of each of the two reinforcing walls to the guide surface so that the two reinforcing walls expand each other. 2 stroke internal combustion engine.   The lateral stiffener (13) is bent from its plane, and one end of a bent or flat reinforcing wall (17 ') is extended from the plane of the lateral stiffener (13) so as to expand the lateral stiffener. Connect to the bent portion of the rigid member (13), and connect both the opposite side of the reinforcing wall (17 ') and the free end of the lateral stiffener member (13) to the back side of the guide surface (14). The two-stroke internal combustion engine according to claim 1.   The two reinforcing walls (17 ') at the bifurcation of the lateral stiffener (13) are formed by plates that go around the retaining bolt (19). 2. A two-stroke internal combustion engine according to item 1.   A part of the retaining bolt (19) is a cavity (18 ') formed between the guide surface (14) and the two reinforcing walls (17') of the bifurcation of the lateral stiffener (13). The two-stroke internal combustion engine according to any one of claims 1 to 5, wherein

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