JPH086874B2 - Anti-vibration device for marine diesel engine - Google Patents

Description

TECHNICAL FIELD The present invention relates to a vibration isolation device for a diesel engine used in ships and the like that require low vibration and noise.

<Prior Art> Conventionally, as a vibration isolator for a diesel engine for a ship, for example, an antivibration rubber is known. This anti-vibration device has a plurality of anti-vibration rubbers made by adhering a natural rubber plate between two steel plates and arranged between the foundation floor of the engine room and the base plate on which the diesel engine is mounted. The steel plate is fixed to the base floor and the other steel plate is fixed to the base plate with bolts, respectively, and the diesel engine is supported on the base floor via the anti-vibration rubber to reduce the vibration and noise transmitted from the engine to the hull. .

<Problems to be Solved by the Invention> However, the above conventional vibration isolator supports a load of an engine in a vertical direction by a plate-shaped vibration isolator having a large pressure receiving area, and the shearing direction of the antivibration rubber, that is, Since the spring constants in the front-rear and left-right directions of the engine are low, the damping effect against vibrations in this direction is not sufficient, and there is a drawback that the engine vibrates when rolling or pitching occurs in the hull.

Therefore, an object of the present invention is to significantly reduce vibrations and noises transmitted from a marine diesel engine to a hull, etc., by using a conventional one-stage flat type vibration-damping rubber in two stages and increasing rigidity in the shearing direction, and The purpose of the present invention is to provide a safe vibration damping device for a marine diesel engine that is prevented and alleviated.

<Means for Solving the Problems> In order to achieve the above object, the vibration isolator of the diesel engine of the present invention is provided between the foundation floor and the base plate on which the diesel engine is mounted, A base plate for accommodating the lower part of a diesel engine in a central part formed lower than a step and mounting the diesel engine, and a horizontal part is arranged between the base plate and the foundation floor, and both sides are arranged. Intermediate base plate having a relatively high rigidity, which has a central portion formed stepwise lower than the step portion, both sides of the intermediate base plate, the base floor, both sides of the intermediate base plate, and both sides of the base plate A pair of anti-vibration rubbers having spring elements constituting a two-stage anti-vibration system for supporting the above-mentioned diesel engine on the foundation floor by arranging a plurality of pairs on the same vertical line on the left and right side views between And the front and rear edges of the intermediate base plate and left A first stopper bracket erected on the foundation floor so as to be in contact with and connected via a vibration-proof rubber member having a spring element constituting a two-stage vibration-proof vibration system on the right edge, and the base plate A second stopper bracket is provided upright on the four circumferences of the intermediate base plate so that the front and rear edges and the right and left edges of the intermediate base plate can be connected to each other via the anti-vibration rubber member.

<Operation> The vibration isolator of the diesel engine of the present invention has a two-stage anti-vibration support structure in which an upper anti-vibration rubber and a lower anti-vibration rubber are fixed on the upper and lower intermediate base plates, respectively, which have relatively high rigidity. Therefore, the vibration in the vertical direction can be reduced more effectively. Moreover, even if the spring constant in the shearing direction is high, it does not increase so much compared to the natural frequency of the conventional vibration isolator due to the heavy intermediate base plate. Moreover, the intermediate base plate that is connected to each other without any gap from the first stopper bracket that is erected on the foundation floor, and the second stopper bracket and the base plate that are erected on this intermediate base plate are used to move the diesel engine in the front-rear and left-right directions. Vibration is stopped and alleviated,
By properly setting the spring constants of the anti-vibration rubber members of both stopper brackets, the 12 natural frequencies of the rigid body vibration of the engine can be adjusted properly, without increasing the vibration amplitude of the engine body and Anti-vibration effect can be obtained. Furthermore, since the central portions of the base plate and the intermediate base plate are stepwise lowered from both sides to accommodate the lower part of the diesel engine, etc., the overall height of the engine is low and the increase in ship width is suppressed. , Can support the engine stably. Therefore, the damping ratio of high-frequency vibration expressed in decibel units by the above-mentioned vibration isolator becomes 1.5 to 2 times that of the conventional one, and the transmissibility of low-frequency vibration is greatly reduced as compared with the conventional one, and the hull is downsized. Can be planned.

<Examples> Hereinafter, the present invention will be described in detail with reference to illustrated examples.

1 and 2 are a side view and a front view showing an embodiment of a vibration isolator according to the present invention, in which 1 is a foundation floor provided at the bottom of the engine room of a ship, and 2 is a stepped shape rather than both sides. The base plate 5 which absorbs and mounts the lower parts of the diesel engine 3 and the generator 4 in the central portion formed at a low level is horizontally arranged between the base plate 2 and the foundation floor 1, and from both sides. Also, as shown in the figure, an intermediate base plate 6 having a central portion formed in a stepwise lower shape and having a relatively high rigidity, 6 is provided between the intermediate base plate 5 and the foundation floor 1 and the base plate 2 on the left and right sides. Anti-vibration rubber as having a spring element constituting a two-step anti-vibration system for supporting the diesel engine 3 and the generator 4 on the foundation floor 1 by installing a plurality of pairs arranged on the same vertical line as viewed from the side. , 7 contact the front and rear edges and the left and right edges of the intermediate base plate 5 so that they can be connected to each other.
A total of eight first stopper brackets, which are erected on the base plate 2, and a total of eight second stopper brackets, which are erected on the four circumferences of the intermediate base plate 5 so as to contact and connect to the front and rear edges and the left and right edges of the base plate 2. It is a stopper bracket.

As shown in FIGS. 4 and 5, the foundation floor 1 has support blocks 12, 12, ... Arranged at a predetermined pitch on rail-shaped foundations 11, 11 laid in the engine room bottom F in the propeller axial direction. Via, the vertical girders 13, 13 made by reinforcing the U-shaped cross-section steel with ribs 14, 14… are fixed, and both vertical girders 13, 13 are connected by multiple horizontal girders 15. Anti-vibration rubber in the lower row on the upper surface of the vertical girder 13 at the rib position
6a is fixed. Also, stopper stands 16 are provided near the front and rear ends on both sides of the rail-shaped foundations 11 and 11, respectively.
The first stopper bracket 7 is fixed to 16, and the first stopper bracket 7 is also fixed to the front and rear ends of each rail-shaped foundation 11.

Further, the base plate 2 has a box body 17 (second
(See FIG. 5, FIG. 5) Horizontally extending support plates 18 and 18 having an L-shaped cross section at approximately the center of the left and right side walls, and arranging the support plates at a predetermined pitch, upper and lower ribs 19 and 20 and the lower surface. Reinforced by a reinforcing plate (21) extended to the upper side, the vibration damping rubber (6b) on the upper stage is fixed to the lower surface of the support plate (18) at each rib position. The lower portions of the diesel engine 3 and the generator 4 are housed in the box 17 and mounted on the base plate 2 and connected to each other by the flexible joint 9a (see FIG. 1), while the diesel engine 3 The output shaft at the rear end is connected by a flexible joint 9b to a speed reducer 10 installed on the engine room floor F through a single vibration isolator. The intermediate base plate 5 arranged between the base plate 2 and the base floor 1 is a box-shaped vertical girder 22,22 extending on the vertical girders 13,13 of the base floor 1 (see FIGS. 4 and 5). Is a plurality of U-shaped horizontal girders 23 that curve along the bottom surface of the box body 17 of the base plate 2.
It will be connected with. In each vertical girder 22, the base plates 24b and 24a are fixed to the upper and lower anti-vibration rubber (6b, 6a) mounting portions, respectively, while the seats 25 are formed on the upper surfaces of the front and rear end portions and the outer portion near the front and rear ends. The second stopper bracket 8 is fixed via the contact plate 26 and the contact plate 26 is fixed to the front and rear end portions and the side contact portions of the first stopper bracket (7).

In the first stopper bracket 7, as shown in FIG. 3, a front plate 28 having two bolt holes 28a is erected on the front surface of a bottom plate 27 having four bolt holes 27a, and the front plate 28 is provided with vertical ribs on both sides. 29, 29 and the bracket portion 31, which is reinforced with the horizontal rib 30,
A contact plate 32 having bolt holes 32a at the four corners and two female screw holes 33a
And a seat plate (33) having a rubber plate (34) bonded to the seat plate (33). Then, as shown in FIG. 4, the anti-vibration rubber member 35 is screwed and fixed to the vertical beam 22 of the intermediate base plate 5 with four bolts inserted into the bolt holes 32a of the contact plate, while the bracket After the part 31 is screwed and fixed to the vertical girder 13 of the foundation floor 1 with four bolts inserted into the bolt holes 27a of the bottom plate, the vibration-proof rubber member 35 and the bracket part 31 are fixed to the bolt holes 28a of the front plate.
And two bolts screwed into the female screw hole 33a of the seat plate. In this way, by connecting the intermediate base plate 5 to the foundation floor 1 via a total of eight first stopper brackets 7, the front-back and left-right vibrations of the intermediate base plate 5 are prevented and alleviated.
The spring constant of the lower vibration-proof rubber 6a in the shearing direction is significantly increased. Further, the configuration and mounting method of the second stopper bracket 8 are substantially the same as those of the first stopper bracket described above, as can be seen from FIG.
Is coupled to the intermediate base plate 5 via a total of eight second stopper brackets 8, the vibration of the base plate 2 in the front-rear direction and the left-right direction is largely prevented and alleviated together with the above-mentioned action.
The spring constant of the upper rubber cushion 6b in the shearing direction remarkably increases.

On the other hand, as shown in FIG. 1, the anti-vibration rubber 6 is provided on the same vertical line between the base floor 1 and the intermediate base plate 5 and the intermediate base plate 5 and the base plate 2 on each side when viewed from the left and right side surfaces. A total of 28 pairs of 14 pairs will be fixed. Each anti-vibration rubber 6 has a thin plate 3 between the upper and lower rectangular plates 36, 37 as shown in FIG.
8 is arranged, natural rubber plates 39, 39 are bonded between these plates, and the lower anti-vibration rubber 6a is the upper anti-vibration rubber
One size larger than 6b. The upper anti-vibration rubber 6b is fixed to the reinforcing plate 21 on the lower surface of the support plate (18) of the base plate 2 with four bolts 40 inserted into the four corners of the upper rectangular plate 36, and the lower rectangular plate 37 is fixed. It is fixed to the base plate 24b on the upper surface of the vertical girder (22) of the intermediate base plate 5 with two bolts 41 inserted in the front and rear of the center. Also,
On the contrary, the lower anti-vibration rubber 6a uses the upper rectangular plate 36 by the two bolts 41 and the base plate 24 on the lower surface of the vertical girder (22).
In b, the lower rectangular plate 37 is fixed to the longitudinal girders 13 of the foundation floor 1 by four bolts 40, respectively.

Further, a counterbore 43 for accommodating the hexagon socket head 42a of the compression bolt 42 is provided in the vicinity of the front and rear ends of the rectangular plate 36 on the upper anti-vibration rubber 6b (see FIG. 4). On the lower rectangular plate 37 facing the
While the female screw hole 44 into which b is screwed is provided, the support plate 18 and the reinforcing plate 21 of the base plate 2 are provided with the through hole 45 through which the counterbore hole 43 is drawn. The counterboring hole 43 and the female screw hole 44 are provided upside down in the lower rubber cushion 6a, and the through hole 45 is provided in the longitudinal girder 13 of the foundation floor 1. Above compression bolt 42
As shown on the right side of FIG. 5, the upper and lower rectangular plates 3 are provided in order to facilitate mounting and removal of the vibration-proof rubber 6.
The 6,37 is tightened to shorten the natural rubber plate 39. Further, as shown in FIG. 4, through screw holes 46 are provided in the support plate 18 and the reinforcing plate 21 of the base plate 2 at several positions near the upper vibration isolating rubber 6b, so that the vibration isolating rubber can be attached and detached. A bolt 47 for keeping a distance from the intermediate base plate 5 is screwed into the through screw hole 46. Similarly, on the upper surface of the vertical girder 13 of the foundation floor 1 at several points in the vicinity of the lower rubber cushion 6a, a female screw block
48 is fixed, and a bolt 49 having a hexagonal portion in the middle is screwed to this female screw block 48 so as to maintain the interval at the time of attaching and detaching the anti-vibration rubber.

The operation of the vibration isolator having the above structure and the method for attaching and detaching the vibration isolator 6 will be described below.

First, when removing the attached anti-vibration rubber 6, the bolts 47 screwed into the through-holes 46 of the support plate 18 and the reinforcing plate 21 of the base plate 2 of FIG. While maintaining the space between the base plates 5, the vertical girders of the foundation floor 1
The bolt 49 screwed to the female screw block 48 on the upper side 13 is tightened upward to maintain the distance between the intermediate base plate 5 and the foundation floor 1. Next, bolts 40 and 41 (the fifth
Through the through hole in the support plate 18
The compression bolt 42 is inserted from above into the counterbore 43 of the rectangular plate 36 on the anti-vibration rubber 6b and the anti-vibration rubber 6b, and the tip 42b thereof is screwed into the female screw hole 44 of the lower rectangular plate 38. Then, tighten the compression bolt 42 until it is completely embedded, and
39 is compressed, and the height of the vibration-proof rubber 6b is shortened to the holding interval of the bolt 47 or less. As a result, the anti-vibration rubber 6b can be easily pulled out together with the compression bolt 42. Also,
Similarly, the lower anti-vibration rubber 6b can be easily pulled out by inserting the compression bolt 42 from below the stringer 13 and tightening it. On the other hand, when installing the anti-vibration rubber 6a, 6b, reverse the above procedure and finally
42 through the base plate 2 or the through hole 45 of the foundation floor 1,
By fixing the anti-vibration rubber with the fixing bolts 40 and 41, it can be easily mounted. Further, the attachment / detachment of the first and second stopper brackets 7 and 8 has already been described in the description of FIG.

The anti-vibration device assembled in this way is used in the diesel engine 3
Supporting the base plate 2 on which the generator 4 and the generator 4 are mounted on the foundation floor 1 via the upper stage anti-vibration rubber 6b, the tall, relatively high rigidity and large mass intermediate base plate 5, and the lower stage anti-vibration rubber 6a. Because of the two-stage anti-vibration structure, the vertical vibration of the base plate 2 can be greatly reduced as compared with the conventional one while suppressing the longitudinal vibration of the base plate 2. Moreover, the foundation floor 1 is connected via the eight first stopper brackets 7.
Since four rounds of the intermediate base plate 5 are connected to each other and four rounds of the base plate 2 are connected to the intermediate base plate 5 via the eight second stopper brackets 8, the spring constant of the vibration isolating rubber 6 in the shearing direction is It is remarkably increased, and vibrations of the base plate 2 in the front-rear direction and the left-right direction are prevented and alleviated. In addition, the center portion of the base plate 2 is made a box 17 lower than both side portions serving as support points, and the cross member 23 of the intermediate base plate 5 is also U-shaped. Since the lower part of the generator 4 is housed, there are advantages that the overall height of the engine can be reduced and the engine can be stably supported. Thus, the high-frequency vibration transmitted from the diesel engine 3 etc. was about 20 dB with the above-mentioned anti-vibration device.
It attenuates to ~ 40dB, and the transmissibility of low frequency vibration is also greatly reduced. Therefore, the damping rate of vibration acceleration is about 1/10 of the conventional example.
Reach Therefore, if this anti-vibration device is applied to a passenger ship or the like, a comfortable riding comfort can be realized due to low vibration and low noise. Since the vibration mode becomes complicated during stormy weather, the structure, performance, and arrangement of the anti-vibration rubber may be optimally determined by computer simulation or the like so as not to hinder navigation.

In the above embodiment, the first and second stopper brackets, the intermediate base plate and the base plate are connected by bolts, respectively, but they may be connected by other means. The number of stopper brackets may be increased or decreased as needed. Further, the generator mounted on the base plate may be omitted, or other devices may be additionally mounted.

Needless to say, the present invention is not limited to the illustrated embodiment.

<Effects of the Invention> As is clear from the above description, in the vibration isolator for a marine diesel engine of the present invention, the base plate on which the diesel engine is mounted has a lower central portion with an upper anti-vibration rubber and a central portion with a stepped shape. A relatively low rigidity intermediate base plate and a two-stage anti-vibration structure that is supported on the foundation floor via the lower stage anti-vibration rubber, and the front and rear of the first stopper bracket and the intermediate base plate standing on the foundation floor , The left and right edges and the second stopper brackets standing upright on the four circumferences of the intermediate base plate are brought into contact with and connected to the front, rear, left and right edges of the base plate via vibration-proof rubber members, respectively, so that they are transmitted from the diesel engine to the foundation floor. The vibration in the vertical direction can be significantly reduced, the spring constant in the shearing direction of the anti-vibration rubber increases, and the vibration of the diesel engine in the front-back and left-right directions is prevented and mitigated against the large shaking of the foundation floor. Lower the overall height of the institution,
And while suppressing the increase in ship width, it can stably support the engine,
It is possible to realize a safe ship that has extremely low vibration and noise and is comfortable to ride.

[Brief description of drawings]

1 and 2 are a side view and a front view showing an embodiment of a vibration isolator of the present invention, FIG. 3 is a view showing a first stopper bracket of the above embodiment, and FIGS. 4 and 5 are It is a detailed side view and a detailed front view showing how to attach and detach the anti-vibration rubber of the above-mentioned embodiment. 1 ... Foundation floor, 2 ... Base plate, 3 ... Diesel engine, 4 ... Generator, 5 ... Intermediate base plate, 6 ... Anti-vibration rubber, 7 ... First stopper bracket, 8 ... Second stopper bracket.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Hiroyuki Akai, Inventor Hiroyuki Akai 1-80 Oyodochu, Kita-ku, Osaka City, Osaka Prefecture Daihatsu Daisel Co., Ltd. 1-80 Daihatsu Daisel Co., Ltd. (72) Inventor Keizo Terada 6-16-1 Hikoshima Enoura-cho, Shimonoseki City, Yamaguchi Prefecture Mitsubishi Heavy Industries, Ltd. Shimonoseki Shipyard (72) Inventor Iwa Honda Nagasaki, Nagasaki Prefecture No. 1-1 No. 1 Nagasaki Research Laboratory, Mitsubishi Heavy Industries, Ltd. (56) Reference JP-A-61-116142 (JP, A) JP-A-61-105320 (JP, A) Actual development: JP-A-61-17332 (JP, U) Japanese Patent Publication Sho 56-49837 (JP, B2)

Claims (1)

[Claims] 1. An anti-vibration device for a marine diesel engine, which is provided between a base floor of a marine vessel and a base plate on which a diesel engine is mounted, wherein the diesel engine is provided in a central portion formed stepwise lower than both side portions. A base plate for accommodating the lower part of the vehicle for mounting the diesel engine, and a central part which is arranged including the horizontal part between the base plate and the foundation floor and is formed stepwise lower than both side parts. A relatively high-rigidity intermediate base plate, arranged on the same vertical line on the left and right side views between both sides of the intermediate base plate and the foundation floor, and both sides of the intermediate base plate and both sides of the base plate. And a plurality of pairs of them are attached to each other to support the diesel engine on the foundation floor. With a spring element that constitutes a step vibration isolation system A first stopper bracket that is erected on the foundation floor so as to be abutted and connected via a vibration-proof rubber member, and the front and rear edges and the left and right edges of the base plate through the vibration-proof rubber member. An anti-vibration device for a marine diesel engine, comprising a second stopper bracket that is erected on the four circumferences of the intermediate base plate so as to be in contact with and connected to each other.