JPH11148425A - Vibration sound reducing device, and vibration sound reducing device for water-cooled internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To secure a sufficient sealing property, after making to reduce the vibration sound effectively in a simple structure with no increase in the weight increase of a passage forming body, in a vibration sound reducing device having a vibration absorbing means to absorb a vibration transmitted from a vibration generating part through the liquid in a liquid passage, at the passage forming body to form a liquid passage to which at least a part of the vibration generating part is faced. SOLUTION: A through hole 171 whose inner end is opened to a liquid passage 14, and a flange form of receiver 18 extruding to the inner side in the radial direction from the inner surface of the through hole 171 , are provided on the outer wall 11b of a passage forming body. And a vibration absorbing means 161 is composed of a blocking member 191 installed on the outer wall 11b by blocking the through hole 171 ; and an elastic membrane 211 whose outer periphery is held between the receiver 18 and the blocking member 191 by making its other surface face onto a space 20 formed between the blocking member 191 , as well as making its one surface face onto the liquid passage 14.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a passage forming member which forms a liquid passage which faces at least a part of a vibration generating portion, and transmits a vibration transmitted from the vibration generating portion via the liquid in the liquid passage. The present invention relates to a vibration noise reduction device provided with vibration absorbing means for absorbing vibration, and more particularly to a vibration noise reduction device suitably applied to a water-cooled internal combustion engine in which a cooling water passage including a water passage surrounding a cylinder is provided in an engine body.

[0002]

2. Description of the Related Art In a water-cooled internal combustion engine, in order to reduce a piston slap noise caused by a collision of a piston with an inner surface of a cylinder portion, a method of increasing a wall thickness of a cylinder portion to reduce a vibration amplitude is disclosed. A technique of increasing the thickness of the outer wall of the cylinder block to suppress the vibration amplitude has been conventionally used.

Further, as a structure for suppressing the vibration of incompressible cooling water existing in a cooling water channel, Japanese Utility Model Application Laid-Open No. 53-6881 is disclosed.
As disclosed in Japanese Patent Application Publication No. 4 (1993) -104, there is known a structure in which a sound insulation layer is provided outside a cooling water channel in a cylinder block via a partition.

[0004]

However, in the above methods, the weight of the engine body increases due to the increase in the thickness of the cylinder portion and the cylinder block. Further, in the above structure, the cooling water passage and the sound insulation layer are arranged via the partition wall, so that the structure is complicated, and the structure is complicated, the production is difficult, the production cost is increased, and the weight of the engine body is increased. It will also be.

Accordingly, the applicant of the present application has proposed a vibration absorbing device having an elastic film in which a through hole is provided in the outer wall of the engine body facing the cooling water channel, and one surface faces the cooling water channel and the other surface faces the space. Japanese Patent Application No. 8-351288 has already proposed a vibration noise reduction device for a water-cooled internal combustion engine in which a means is attached to the outer wall surface of the engine body so as to close the through hole.

According to this proposed technique, the pressure fluctuation of the cooling water is absorbed by the bending of the elastic film having one surface facing the cooling water passage, and the exciting force acting on the outer wall of the engine body from the cooling water. Is effectively reduced, and the piston slap noise radiated from the engine body is reduced without increasing the weight of the engine body.

However, in the above proposed technique, the peripheral portion of the elastic film is fixed to a member attached to the engine body so as to close the through hole by baking or the like. It is difficult to secure a sufficient seal between the cooling water channel and the space due to the deterioration of the water pressure and the elastic film of the water channel. In addition, it is conceivable to attach the peripheral edge of the elastic film to a member attached to the engine body, but in such a case, it is difficult to ensure a sufficient sealing property.

The present invention has been made in view of the above circumstances, and is intended to effectively reduce vibration noise such as piston slap noise with a simple structure that does not increase the weight of the passage forming body. It is another object of the present invention to provide a vibration noise reduction device capable of ensuring a sufficient sealing property.

[0009]

In order to achieve the above object, according to the present invention, the vibration generating unit is provided in a passage forming body which forms a liquid passage facing at least a part of the vibration generating unit. A vibration-absorbing device provided with vibration absorbing means for absorbing vibration transmitted through the liquid in the liquid passage from a through-hole having an inner end opened in the liquid passage;
A flange-shaped receiving portion extending radially inward from an inner surface of the through hole is provided on an outer wall portion of the passage forming body, and a closing member that closes the through hole and is attached to the outer wall portion; Vibration absorbing means is constituted by an elastic film having an outer peripheral portion sandwiched between the receiving portion and the closing member with the other surface facing the space formed between the closing portion and the liquid passage while facing the liquid passage. It is characterized by that.

According to the configuration of the first aspect of the present invention, the vibration generated in the vibration generating section induces the vibration of the liquid in the liquid passage, but one surface is made to face the liquid passage. Fluctuations in the pressure of the liquid are absorbed by the flexure of the elastic film, and the vibrating force acting on the outer wall of the passage forming body from the liquid is effectively reduced, and the vibration sound radiated from the passage forming body is reduced. Will be. Moreover, since the vibration absorbing means is attached to a part of the outer wall side of the passage forming body,
It is possible to minimize the increase in the weight of the passage forming body due to the attachment of the vibration absorbing means. Further, the elastic film is sandwiched between the receiving portion provided on the outer wall portion of the passage forming body and the closing member. The elastic film avoids the deterioration of the sealing property due to the liquid pressure of the liquid passage and the deterioration of the elastic film. The membrane can be securely clamped between the closing member and the receiving portion,
Sufficient sealing performance can be ensured as compared with the case where the elastic film is directly fixed to the closing member by baking or bonding. Further, by preventing the elastic film from protruding into the liquid passage, it is possible to prevent the flow of the liquid in the liquid passage from being obstructed, and the space is not surrounded by the liquid in the liquid passage. The vibration characteristics of the elastic film can be prevented from changing with the temperature change, and the vibration characteristics can be stabilized.

[0011] The invention according to claim 2 provides the above-mentioned claim 1.
In addition to the configuration of the invention described, a cylindrical boss portion having a through hole is integrally provided on an outer wall portion of the passage forming body,
On the outer peripheral portion of the elastic film sandwiched between the receiving portion and the closing member, an annular lip that is in close contact with the receiving portion is provided to project,
The closing member is integrally provided with a regulating flange portion that contacts an outer end of the boss portion to regulate a moving end of the closing member in a direction approaching the receiving portion. According to this, it is possible to improve the sealing performance by crushing the lip, and it is possible to set the crushing allowance of the lip to a set value by abutting the regulating flange on the outer end of the boss. In addition, it is not necessary to attach the closing member to the outer wall while taking into account the crushing allowance of the lip, thereby making it possible to improve the assemblability.

According to a third aspect of the present invention, in addition to the configuration of the first or second aspect of the present invention, an engaging portion for engaging with the closing member is provided on an outer peripheral portion of the elastic film. According to such a configuration, not only can the elastic film be reliably prevented from falling off from between the receiving portion and the closing member, but also the vibration absorbing means can be provided with the elastic film attached to the closing member. Can be attached to the outer wall portion of the passage forming body, so that the assembling operation is facilitated.

According to a fourth aspect of the present invention, in addition to the configuration of the third aspect of the present invention, the closing member is provided with a cylindrical portion for holding an outer peripheral portion of the elastic film between the receiving portion and the cylindrical portion. An engaging portion formed in a cylindrical shape so as to resiliently fit into an annular concave portion provided on the outer periphery of the distal end of the cylindrical portion in a tapered shape having a smaller diameter as approaching the receiving portion; According to this structure, the cylindrical portion of the closing member is fitted to the engaging portion while avoiding damage to the elastic film. The elastic film exerts a resilient force to bring the inner surface of the engaging portion into close contact with the annular recess when the cylindrical portion is fitted to the engaging portion, so that the inner surface of the engaging portion can be easily mounted. The seal is further improved by closely contacting the entire surface with the annular recess. It can be.

According to a fifth aspect of the present invention, a cooling water passage including a water passage surrounding the cylinder is formed in an engine body including a cylinder block provided with a cylinder for slidably fitting a piston. In addition, in a vibration noise reduction device of a water-cooled internal combustion engine provided with vibration absorbing means for absorbing vibration transmitted from the cylinder portion through cooling water in a cooling water passage, the cooling water passage may have an inner end opened. A hole, a flange-shaped receiving portion extending radially inward from an inner surface of the through hole, provided on an outer wall of the engine main body, and closing the through hole to be attached to the outer wall; Vibration absorbing means is provided by an elastic film having an outer peripheral portion sandwiched between the receiving portion and the closing member, with one surface facing the cooling water passage and the other surface facing a space formed between the cooling member and the closing member. Characterized in that it is made.

According to the structure of the fifth aspect of the invention, the vibration of the cylinder caused by the collision of the piston with the inner surface of the cylinder induces the vibration of the cooling water in the cooling water passage. However, the pressure fluctuation of the cooling water is absorbed by the bending of the elastic film having one surface facing the cooling water passage, and the exciting force acting on the outer wall of the engine main body from the cooling water is effectively reduced. Thus, the piston slap noise radiated from the engine body is reduced. Moreover, since the vibration absorbing means is attached to a part of the outer wall side of the engine main body, an increase in the weight of the engine main body due to the mounting of the vibration absorbing means can be minimized. The elastic film is sandwiched between the receiving portion and the closing member provided on the outer wall portion of the passage forming body. The elastic film avoids a decrease in sealing performance due to the water pressure of the cooling water passage and deterioration of the elastic film. Receiving part and the closing member can be securely clamped,
Sufficient sealing performance can be ensured as compared with a structure in which the closing member is directly fixed to the closing member by baking or bonding.
Furthermore, since the elastic film is prevented from protruding into the cooling water channel, it is possible to prevent the liquid flow in the cooling water channel from being obstructed, so that a conventional water-cooled internal combustion engine that is not equipped with vibration absorbing means is provided. Since the same cooling performance can be obtained, and the space is not surrounded by the cooling water in the cooling passage, the vibration characteristics of the elastic film are prevented from changing due to the temperature change of the cooling water. And an excellent vibration absorbing effect during engine operation can be obtained.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described based on embodiments of the present invention shown in the accompanying drawings.

1 to 5 show a first embodiment of the present invention. FIG. 1 is a perspective view of a cylinder block of a four-cylinder water-cooled internal combustion engine, and FIG. 2 is an enlarged sectional view taken along line 2-2 of FIG. Figure,
3 is an enlarged view of a main part of FIG. 2, FIG. 4 is a diagram showing a vibration mode of an outer wall surface of a cylinder block along an arrangement direction of each cylinder portion, and FIG. 5 is a diagram showing a vibration acceleration characteristic with respect to frequency in comparison with a conventional one. is there.

1 and 2, a cylinder block 11 of a water-cooled four-cylinder internal combustion engine constitutes an engine body E as a passage forming body together with a cylinder head and an oil pan (not shown). the 11, first to fourth cylinder unit _131-134 are provided in parallel a vibration generating unit, the piston 12 ... we are engaged respectively slidably in the cylinders portions _131-134 . These cylinder portions _131-134 are
In this embodiment, the inner wall portion 1 of the cylinder block 11 is provided.
The cylinder liners 15 are cast into 1a, but may be formed by grinding the inner surface of the inner wall 11a. The also engine body E, the cooling water channel 14 as a liquid passage for circulating cooling water is formed, the cooling water channel 14 is formed in the cylinder block 11 so as to surround the respective cylinder portions _131-134 in common Including the water channel part 14a.

By the way, the piston 12 ... are present slight gaps between the outer and inner surfaces of the cylinder portions _131-134 of the piston 12 ... vertical movement of the respective cylinder portions _131-134 within ₄ Sometimes pistons 12 are cylinder parts 1
3 _{1-13 4} collides with the inner surface cylinder unit _131-134
4 is vibrated, and the vibration is transmitted to the cooling water in the cooling water passage 14. Since the cooling water is incompressible,
Even a slight vibration causes a pressure change, and the cooling water passage 14
When a vibration force is applied to the outer wall 11b of the cylinder block 11 facing the pressure due to the change in the pressure of the cooling water, the outer wall 11b vibrates, and the piston slap sound is emitted to the outside.

Therefore, the vibration absorbing means 16 ₁ for absorbing the vibration of the cooling water in the cooling water passage 14 and minimizing the application of the vibrating force to the outer wall 11 b of the cylinder block 11 to reduce the piston slap noise. but the cylinders 13 ₁ ~
13 second and third in an intermediate position along the _fourth arrangement direction
In positions corresponding to the sleeve bore center of the cylinder portion 13 _2, 13 _3, which is attached to the outer wall portion 11b of the cylinder block 11, a cylinder block 1
The first outer wall 11b, and through-holes 17 ₁ ... inner end corresponding to the vibration absorbing means 16 ₁ ... with provided so as to open the water passage portion 14a, the inner from the through holes 17 ₁ ... inner surface of Receiving portions 18 projecting in the direction.

The vibration absorbing means 16 ₁ has a closing member 19 ₁ for closing the through hole 17 ₁ , and one surface of the water passage portion 14 of the cooling water passage 14.
and an elastic film 21 ₁ is sandwiched between the receiving portion 18 and the closure member 19 ₁ to face the other surface in the space 20 formed between the closing member 19 ₁ causes face to a.

Referring also to FIG. 3, a cylindrical boss 22 is integrally formed on the outer wall portion 11b of the cylinder block 11, and a through hole 17 having an inner end opened to the water passage portion 14a. ₁ is provided on the outer wall portion 11b such that the outer end thereof opens to the outer end of the boss portion 22. Receiving part 1
8 is formed in a flange shape that overhangs radially inwardly from the inner end inner surface of the through hole 17 _1.

The closing member 19 ₁ has a cylindrical portion 2 whose outer end is closed.
3 ₁ and a regulating flange 24 ₁ extending radially outward from the outer end of the cylindrical portion 23 ₁ , and is formed of a rigid metal material such as an aluminum alloy. _{by 1} is pressed from the outer side into the through-hole 17 _1, the outer wall 11b of the engine body E closes the through-hole 17 ₁
To be fixedly mounted on the vehicle. Thus, the closing member 1
By 9 ₁ of restricting collar portion 24 ₁ is brought into contact with the outer end of the boss portion 22, so that the press-fitting movement end in the direction toward the receiving portion 18 of the closing member 19 ₁ is restricted.

The elastic film 21 ₁ is, for example, those comprising ethylene-propylene rubber, the outer peripheral portion of the disc-shaped membrane 25 which is inserted into the through hole 17 _1, annular lip 26
There are those formed by integrally projecting, the outer peripheral portion of the elastic membrane 21 ₁ is closed by a press fit to the member 19 ₁ of the through-hole 17 _1, the distal end portion of the cylindrical portion 23 ₁ of the closing member 19 ₁ and receives The lip 26 is sandwiched between the portions 18 so as to be crushed. Thus to closing member 19 ₁ and the receiving portion 18
One end of the elastic film 21 ₁ are in a state of being sandwiched between will be facing the water channel 14a of the cooling water channel 14, also the elastic membrane 2
1 ₁ at the other end would face the space portion 20 formed between the elastic film 21 ₁ and the closing member 19 _1.

By the way, the arrangement position of the through hole 17 ₁ and the vibration absorbing means 16 _1, it is desirable piston 12 is close to the position to hit the second and third cylinder portions 13 _2, 13 ₃ of the inner surface, The generation timing of the slap vibration with respect to the crank angle is 25 before and after the top dead center of the piston 12.
Since it is known that the sum is within 25 degrees, the sum of the piston displacement amount at 25 degrees before and after the top dead center and the axial length of the piston 12 is A, Through hole 17 ₁ and vibration absorbing means 16 ₁
Is desirably provided.

According to the experiment of the inventor, each cylinder
Part 13₁~ 13_FourWith the impact from the piston 12
The speed amplitude of the motion is₁~ 13_FourArray of
Along the direction as shown in FIG.
Linda unit 13₁~ 13_FourIt is the middle part along the arrangement direction of
2nd and 3rd cylinder part 13_Two, 13_ThreeSleevebo
The velocity amplitude increases at the portion corresponding to the center. I
Therefore, the through hole 17 ₁And vibration absorbing means 16₁Is
Each cylinder 13₁~ 13_FourSideways orthogonal to the array direction of
In the state where the cylinder block 11 is viewed from the
3 cylinder section 13_Two, 13_ThreeTo the sleeve bore center
In the corresponding portion, the outer wall portion 11b of the cylinder block 11
It is desirable to be arranged respectively.

Next, the operation of the first embodiment will be described. The outer surface of each piston 12 and each cylinder 13
By minute gap exists between _{1-13 4} inner surface,
When the inner surface of the cylinder portion _131-134 piston 12 ... vibrates the respective cylinder portions _131-134 collide,
The vibration is transmitted to the incompressible cooling water in the cooling water passage 14 and induces a pressure change of the cooling water. However, the outer wall 11b of the cylinder block 11 at a portion facing the water passage portion 14a of the cooling water passage 14, the through hole 17 _1,
A flange-shaped receiving portion 18 overhangs radially inwardly from the inner end inner surface of the through hole 17 ₁ is provided, mounted vibration absorbing means 16 ₁ so as to block the through hole 17 _1, the vibration absorbing means 16 _1, closed and the closing member 19 _1, which is fixedly attached to the outer wall 11b closing the through-hole 17 _1, causes face the one side to the water passage portion 14a of the cooling water channel 14 member 19
Composed of _one elastic film 21 ₁ and the entire outer peripheral portion is held between the receiving portion 18 and the closure member 19 ₁ to face the other surface in the space 20 formed between the. Therefore, the pressure fluctuation of the cooling water will be absorbed by the deflection of the membrane portion 25 in the elastic film 21 _1, the cylinder block 1 from the cooling water
The exciting force acting on the outer wall 11b of the first outer wall 11b is effectively reduced. Moreover, since the space portion 20 facing the other surface of the elastic film 21 ₁ is covered with a closing member 19 _1, without the sound by the vibration of the elastic membrane 21 ₁ is radiated to the outside from the closing member 19 _1,
Piston slap noise radiated from the cylinder block 11 can be effectively reduced.

Furthermore the vibration absorbing means 16 ₁ to a part of the outer wall side of the cylinder block 11 is intended to be mounted, to suppress the increase in weight of the cylinder block 11 i.e. the engine body E by mounting the vibration absorbing means 16 ₁ as small as possible Can be.

Further the outer periphery entire periphery of the elastic membrane 21 ₁ is intended to be clamped between the closing member 19 ₁ and the receiving portion 18,
To avoid that the sealing property decreases by the water pressure and the elastic film 21 ₁ of the degradation of the cooling water channel 14, it is possible to reliably sandwich the elastic film 21 ₁ between the closing member 19 ₁ and the receiving portion 18, the elastic film Superior sealing performance can be ensured as compared with the one directly fixed to the closing member by baking or bonding.

[0030] Moreover since no space 20 is surrounded by the cooling water of the cooling water channel 14, stabilize the vibration characteristics to avoid that the vibration characteristic of the elastic membrane 21 ₁ changes with the temperature change of the cooling water As a result, an excellent vibration absorbing effect can be obtained during engine operation.

[0031] On the outer peripheral portion of the elastic membrane 21 _1, the receiver 1
8 annular lip 26 which closely are projecting, the closing member 19 ₁ sandwiched between the elastic film 21 ₁ of the outer peripheral portion all around the receiving portion 18, the receiving portion 18 of the closing member 19 ₁ since restricting collar portion 24 ₁ for restricting the outer end in contact with the boss portion 22 a moving end along the move or press-fitting direction of the direction toward is integrally provided, improving the sealing property so as to collapse the lip 26 Lip 2
6 squeeze of, it is possible to define the set value by the abutment of the regulating collar portion 24 ₁ to the outer end of the boss portion 22, the lip 2
In consideration of the crushing allowance of 6, the closing member 19 ₁ is inserted into the through hole 17 _1.
It is not necessary to press-fit into the hole, and it is possible to improve the assemblability.

Furthermore the elastic membrane 21 ₁ is the cylinder block 1
Do not protrude from the inner surface of the outer wall portion 11b into the cooling water channel 14 in 1, it can be avoided as much as possible that the flow of cooling water in the cooling water passage 14 by the elastic film 21 ₁ is inhibited, in the cooling water channel 14 can be of the circulation of the cooling water can be smoothly, to maintain the cooling performance to the same extent as conventional water-cooled internal combustion engine vibration absorbing means 16 ₁ is not equipped.

[0033] Here, when showing the results of verification of the vibration acceleration of the outer wall 11b of the cylinder block 11 at a portion corresponding to the third cylinder portion 13 _3, which is shown in FIG. 5, the vibration absorbing means 16 Whereas the conventional _one having no ₁ is relatively high as shown by the broken line, the one according to the present invention has the acceleration effectively reduced as shown by the solid line, and the vibration absorbing means according to the present invention 16 it is apparent _{that 1} by may reduce piston slap sound effectively.

FIG. 6 shows a second embodiment of the present invention, in which parts corresponding to those of the first embodiment are denoted by the same reference numerals.

On the outer wall 11b of the cylinder block 11,
Is a through hole 17₁And the through hole 17₁Inside the inner end of
And a receiving portion 18 extending radially inward from the
Hole 17 ₁Vibration absorbing means 16_TwoIs Shirin
It is attached to the outer wall portion 11b of the
Collection means 16_TwoIs the through hole 17₁Closing member 19 for closing
_TwoWhen one side faces the water channel part 14a of the cooling water channel 14,
Both closing members 19_TwoIn the space 20 formed between
The receiving portion 18 and the closing member 19 _TwoBetween
Elastic membrane 21 to be sandwiched_TwoAnd

The closing member 19 _2, cylindrical portion 2 closing the outer end
3 ₂ and, from the outer end of the cylindrical portion 23 ₂ and a restricting collar portion 24 ₂ which overhangs radially outwardly, which is formed of a metal material such as aluminum alloy having a rigid, restricting collar portion 24 ₂ cylindrical portion 23 ₂ so as to abut against the outer end of the boss portion 22 is press-fitted from the outer side into the through-hole 17 _1.
Moreover the tip portion outer periphery of the cylindrical portion 23 _second annular recess 28 ₁ is formed.

On the other hand, the elastic film 21 _2, a disc-shaped membrane portion 25
Outer peripheral annular lip 26 on the outer peripheral portion while being integrally projecting, cylindrical engaging portion 27 ₁ for engaging the closure member 19 _{and second} annular recess 28 to ₁ resiliently manner of the membrane portion 25 of the It is formed integrally with the part.

[0038] According to the second embodiment, the addition to the effects of the first embodiment, the receiving portion 18 and the closing member by the engaging portion 27 ₁ is closing member 19 ₂ resiliently to fit 1
9 the elastic membrane 21 ₂ from between ₂ falls off it is possible to reliably prevent the would, elastic film 2 further closure member 19 ₂
The outer wall portion 11 a vibration absorbing means 16 ₂ in a state of wearing the 1 ₂
Since it can be attached to b, the assembling work becomes easy.

FIG. 7 shows a third embodiment of the present invention, and portions corresponding to the above embodiments are given the same reference numerals.

On the outer wall 11b of the cylinder block 11,
Is a through hole 17₁And the through hole 17₁Inside the inner end of
And a receiving portion 18 extending radially inward from the
Hole 17 ₁Vibration absorbing means 16_ThreeIs Shirin
It is attached to the outer wall portion 11b of the
Collection means 16_ThreeIs the through hole 17₁Closing member 19 for closing
_ThreeWhen one side faces the water channel part 14a of the cooling water channel 14,
Both closing members 19_ThreeIn the space 20 formed between
The receiving portion 18 and the closing member 19 _ThreeBetween
Elastic membrane 21 to be sandwiched_ThreeAnd

Blocking member 19_ThreeIs a through hole 17₁Pressed into
Cylindrical part 23_ThreeAnd the cylindrical portion 23 _ThreeRadial from outer edge of
A regulating flange that projects outward and can abut the outer end of the boss portion 22
Part 24_ThreeAnd the cylindrical portion 23_ThreeTip of
On the outer circumference, a taper having a smaller diameter as it approaches the receiving portion 18 is formed.
Annular concave portion 28_TwoIs formed.

On the other hand, the elastic film 21 _3, a disc-shaped membrane portion 25
The outer periphery of an annular lip 26 is projected integrally with the outer peripheral portion, the closure member 19 _third annular recess 28 ₂ resiliently to the cylindrical engaging portion 27 ₂ for fitting of the membrane portion 25 parts to are those formed by integrally connected, the inner surface of the engaging portion 27 ₂ is formed in a tapered shape corresponding to the annular recess 28 _2.

According to the third embodiment, the engaging portion 27_TwoBut
Closing member 19_ThreeReceiving part by elastically fitting
18 and closing member 19_ThreeElastic membrane 21 from between_ThreeDropped out
Of the closing member 19
_ThreeElastic membrane 21_ThreeWith the vibration absorbing means 16_Three
Can be attached to the outer wall 11b,
Can be easy. Furthermore, a tapered annular concave portion 2
8_TwoEngaging portion 27 which is tapered_TwoResiliently mates
Therefore, the closing member 19_ThreeCylindrical part 23_ThreeThe elastic film 21_ThreeBut
Make sure that the engaging portion 27 is not damaged._TwoTo fit
And closing member 19_ThreeElastic membrane 21 to_ThreeEasy installation
And the engaging portion 27_TwoCylindrical part 23 to
_ThreeWhen the elastic film 21 is_ThreeIs the engaging portion 27_TwoInside
Annular recess 28_TwoExerts a resilient force that closely contacts the
Joint 27_TwoThe inner surface of the annular recess 28 _TwoDense throughout
The sealing properties can be further improved by being in contact therewith.

FIG. 8 shows a fourth embodiment of the present invention, in which parts corresponding to the above embodiments are given the same reference numerals.

On the outer wall portion 11b of the cylinder block 11,
Is a through hole 17₁And the through hole 17₁Inside the inner end of
And a receiving portion 18 extending radially inward from the
Hole 17 ₁Vibration absorbing means 16_FourIs Shirin
It is attached to the outer wall portion 11b of the
Collection means 16_FourIs the through hole 17₁Closing member 19 for closing
_FourWhen one side faces the water channel part 14a of the cooling water channel 14,
Both closing members 19_FourIn the space 20 formed between
The receiving portion 18 and the closing member 19 _FourBetween
Elastic membrane 21 to be sandwiched₁And

Closing member 19_FourIs a through hole 17₁Pressed into
Cylindrical part 23_FourAnd the cylindrical portion 23 _FourRadial from outer edge of
A regulating flange that projects outward and can abut the outer end of the boss portion 22
Part 24_FourAnd the cylindrical portion 23_FourTip of
A chamfered portion 29 that is smoothly curved is formed on the inner periphery.
You.

[0047] According to the fourth embodiment, the elastic film 21 central portion of the film unit 25 when inflated to curved into the space 20 side in _1, the tip portion inner periphery of the cylindrical portion 23 ₄ in membrane unit 25 will be chamfer 29 contacts the corresponding portion, the membrane portion 25 by contact with the distal end portion inner periphery of the cylindrical portion 23 ₄ can be prevented from being damaged.

FIG. 9 shows a fifth embodiment of the present invention, and portions corresponding to the above embodiments are given the same reference numerals.

On the outer wall portion 11b of the cylinder block 11,
Is a through hole 17₁And the through hole 17₁Inside the inner end of
And a receiving portion 18 extending radially inward from the
Hole 17 ₁Vibration absorbing means 16_FiveIs Shirin
It is attached to the outer wall portion 11b of the
Collection means 16_FiveIs the through hole 17₁Closing member 19 for closing
_FiveWhen one side faces the water channel part 14a of the cooling water channel 14,
Both closing members 19_FiveIn the space 20 formed between
The receiving portion 18 and the closing member 19 _FiveBetween
Elastic membrane 21 to be sandwiched₁And

The closure member 19 ₅ is one formed by press-molding a metal plate such as JIS SP, radial and cylindrical portion 23 _5, which is pressed into the through-hole 17 _1, the outer end of the cylindrical portion 23 ₅ outward Te overhang is one having a regulating collar portion 24 ₅ at the outer end that may contact the boss portion 22.

According to the fifth embodiment, the closing member 19 ₅
Since There are those formed by press molding a metal plate, weight i.e. the vibration of the closure member 19 ₅ absorbing means 16
₅ can be reduced in weight. Thus, it is possible by mounting the vibration absorbing means 16 ₅ to avoid vibration mode changes at the surface of the cylinder block 11, to obtain a sufficient piston slap noise reduction effect.

10 and 11 show a sixth embodiment of the present invention. FIG. 10 is a longitudinal sectional view of the vibration absorbing means corresponding to FIG. 3, and FIG. 11 shows a state before the closing member is attached. It is sectional drawing corresponding to FIG.

On the outer wall 11b of the cylinder block 11,
Is a through hole 17_TwoAnd the through hole 17_TwoInside the inner end of
And a receiving portion 18 extending radially inward from the
Hole 17 _TwoVibration absorbing means 16₆Is Shirin
It is attached to the outer wall portion 11b of the
Collection means 16₆Is the through hole 17_TwoClosing member 19 for closing
₆When one side faces the water channel part 14a of the cooling water channel 14,
Both closing members 19₆In the space 20 formed between
The receiving portion 18 and the closing member 19 ₆Between
Elastic membrane 21 to be sandwiched₁And

[0054] the inner surface of the through-hole 17 _2, internal thread 30 over a period of from outer position to the outer end of the through-hole 17 ₂ than receiving portion 18 is engraved.

[0055] closure member 19 _6, cylindrical portion 2 closing the outer end
3 _6, the regulating collar portion 24 ₆ which may contact with the outer end of the boss portion 22 Te projecting radially outwardly from the outer end of the cylindrical portion 23 _6,
Are those having an engaging operating portion 31 which protrudes outward from the outer end of the cylindrical portion 23 ₆ to have the potential as to e.g. hexagonal cross-section to engage a tool such as a wrench, cylindrical the outer surface of section 23 _6, the through-hole 17 ₂ of the female screw 3
A male screw 32 screwed into 0 is engraved.

[0056] That closure member 19 _6, the external thread 32 into the internal thread 30 as screwed, which is screwed the regulating collar portion 24 ₆ into the through-hole 17 ₂ to abut the outer end of the boss portion 22 , the tip of the cylindrical portion 23 ₆ and the receiving unit 1
Between 8, the outer peripheral portion of the elastic film 21 ₁ is held so as to form a space portion 20 between the closure member 19 _6.

[0057] By Thus to rotational operation of the closing member 19 _6,
To the tip of the cylindrical portion 23 ₆ to prevent the elastic film 21 ₁ is damaged in sliding contact with the outer peripheral portion of the elastic membrane 21 _1, Fig. 1
As shown in 1, preventing the least one of the distal end portion of the outer peripheral portion the outer surface side and the cylindrical portion 23 ₆ of the elastic film 21 ₁ has been previously grease 33 is coated by the grease 33 damage of the elastic film 21 ₁ Is done.

According to the sixth embodiment, the closing member 19 ₆
But since it is intended to be screwed into the through holes 17 _2, detachable operation on the engine body E of the vibration absorbing means 16 ₆ is facilitated.

Although the embodiments of the present invention have been described in detail, the present invention is not limited to the above embodiments, and various design changes can be made without departing from the present invention described in the appended claims. It is possible to do.

For example, in the above embodiment, the case where the present invention is applied to a water-cooled internal combustion engine has been described. However, the present invention radiates from a passage forming member which forms a liquid passage at least partially facing a vibration generating portion. The present invention can be widely implemented as a device for reducing the generated vibration sound.

[0061]

As described above, according to the first aspect of the present invention, the vibrating force acting on the passage forming body via the liquid from the vibration generating portion is effectively reduced by the flexure of the elastic film, thereby forming the passage. Vibration noise radiated from the body can be reduced, and increase in weight of the passage forming body due to attachment of the vibration absorbing means can be suppressed as small as possible. In addition, it is possible to prevent the sealing property from deteriorating due to the liquid pressure in the liquid passage and the deterioration of the elastic film, and to securely clamp the elastic film between the closing member and the receiving portion. Excellent sealing properties can be obtained as compared with those directly fixed. Further, it is possible to prevent the elastic film from protruding into the liquid passage, thereby preventing the liquid from flowing through the liquid passage, and to prevent the vibration characteristic of the elastic film from changing with the temperature change of the liquid. Avoidance can stabilize the vibration characteristics.

According to the second aspect of the present invention, it is possible to improve the sealing performance by crushing the lip, and to attach the closing member to the outer wall while considering the lip crushing allowance. It becomes unnecessary and the assembling property can be improved.

According to the third aspect of the present invention, it is possible to reliably prevent the elastic film from falling off from between the receiving portion and the closing member, and to absorb vibration while the elastic film is mounted on the closing member. The means can be attached to the outer wall of the passage forming body, so that the assembling operation can be facilitated.

According to the fourth aspect of the present invention, it is possible to easily attach the elastic film to the closing member by fitting the cylindrical portion to the engaging portion while avoiding damage to the elastic film. In addition, the elastic film exerts a resilient force to make the inner surface of the engaging portion closely contact the annular concave portion, so that the inner surface of the engaging portion closely contacts the entire annular concave portion, so that the sealing performance can be further improved.

Further, according to the fifth aspect of the present invention, the exciting force acting on the outer wall of the engine main body from the cylinder through cooling water in the cooling water passage is effectively reduced, and is radiated from the engine main body. The piston slap noise can be reduced, and the weight increase of the engine main body due to the attachment of the vibration absorbing means can be suppressed as small as possible. In addition, it is possible to prevent the sealing performance from being deteriorated due to the water pressure of the cooling water passage and the deterioration of the elastic film, and to securely clamp the elastic film between the receiving portion and the closing member. It is possible to obtain a better sealing claim than the one that is fixed. Furthermore, it prevents the elastic film from protruding into the cooling water channel to prevent the flow of liquid in the cooling water channel from being hindered, and has the same cooling performance as a conventional water-cooled internal combustion engine that is not equipped with vibration absorbing means. Can be obtained, and the vibration characteristics of the elastic film are prevented from changing with the temperature change of the cooling water, thereby stabilizing the vibration characteristics and obtaining an excellent vibration absorbing effect during the operation of the engine.

[Brief description of the drawings]

FIG. 1 is a perspective view of a cylinder block of a four-cylinder water-cooled internal combustion engine according to a first embodiment.

FIG. 2 is an enlarged sectional view taken along line 2-2 of FIG.

FIG. 3 is an enlarged view of a main part of FIG. 2;

FIG. 4 is a diagram showing a vibration mode of an outer wall surface of a cylinder block along an arrangement direction of each cylinder portion.

FIG. 5 is a diagram showing a vibration acceleration characteristic with respect to a frequency in comparison with a conventional case.

FIG. 6 is a sectional view corresponding to FIG. 3 of a second embodiment.

FIG. 7 is a sectional view of a third embodiment corresponding to FIG.

FIG. 8 is a sectional view corresponding to FIG. 3 of a fourth embodiment.

FIG. 9 is a sectional view of a fifth embodiment corresponding to FIG.

FIG. 10 is a sectional view of a sixth embodiment corresponding to FIG. 3;

11 is a cross-sectional view corresponding to FIG. 10 in a state before the closing member is attached.

[Explanation of symbols]

11 ... cylinder block 11b ... outer wall 12 ... piston _131-134 ... cooling water passage 16 ₁ to 16 _8, ... as the cylinder portion 14 ... liquid passage as a vibration generating unit Vibration absorbing means 17 ₁ , 17 ₂ ... through-hole 18 ... receiving part 19 _{1 to} 19 ₆ ... closing member 21 _{1 to} 21 ₃ ... elastic film 20 ... space part 22 ... boss part 23 ₃ ... cylindrical portion 24 _{1-24 6} ... restricting flange portion 26 ... lip 27 _1, 27 ₂ ... engine body as an engaging portion E ... passage defining member

 ──────────────────────────────────────────────────続 き Continued from the front page (72) Inventor Motoyuki Sunaoka 1-4-1, Chuo, Wako, Saitama Prefecture Inside Honda R & D Co., Ltd. (72) Masao Sakashita 1-4-1, Chuo, Wako, Saitama Prefecture No. Within Honda R & D Co., Ltd. (72) Inventor Noriaki Kawai 1-4-1 Chuo, Wako-shi, Saitama Pref.

Claims (5)

[Claims] [Claim 1] A vibration generating unit _(131-134) of at least a portion of the face was liquid passage (14) forming a passage defining member (E), the vibration generating unit _(131-134) the vibration absorbing means (16 ₁ to 16 ₆₎ vibration sound reducing device which is provided is to absorb vibrations transmitted through the liquid in the liquid passage (14) in the, allowed opening inner end to said liquid passageway (14) The through hole (17 ₁ , 17 ₂ ) and a flange-shaped receiving portion (18) projecting inward in the radial direction from the inner surface of the through hole (17 ₁ , 17 ₂ ) are formed by the passage forming body (E). Of the through-hole (17 ₁ , 1)
The outer wall portion 7 ₂₎ closing the the (closure member attached to 11b) (19 ₁ ~ 19 _6), said liquid passage one side (1
Said closure member causes face 4) (19 ₁ to 1
9 wherein the receiving portion so as to face the other surface in the space (20) formed between the ₆₎ (18) and the closing member (19 ₁ to 19
₆ ) Elastic membrane (21 _{1 to} 21 ₃ ) between which outer periphery is sandwiched
Vibration sound reducing device vibration absorbing means (16 ₁ to 16 ₆₎ is characterized in that it is composed of a. 2. An outer wall portion (11) of the passage forming body (E).
b) has a through hole (17₁, 17_Two) With cylindrical
A boss (22) is provided integrally with the receiving portion (18).
And the closing member (19₁~ 19₆) Elastic membrane sandwiched between
(21₁~ 21 _Three), The receiving portion (18)
An annular lip (26) protruding from the closing member
(19₁~ 19₆) Includes the closing member (19).₁~ 19
 ) In the direction approaching the receiving portion (18).
A regulating flange that contacts the outer end of the boss (22) to control
(24₁~ 24₆) Are provided integrally.
The vibration noise reduction device according to claim 1. The outer periphery of claim 3 wherein said resilient membrane (21 _2, 21 _3), that the engaging portion for engaging the closure member (19 _2, 19 ₃₎ (27 _1, 27 ₂₎ provided The vibration sound reduction device according to claim 1 or 2, wherein: The method according to claim 4 wherein said closure member (19 _3), cylindrical portion sandwiched between the receiving portion and the outer peripheral portion (18) (23 ₃₎ provided in said elastic membrane (21 _3), the receiving Department (1
An annular recess (2) provided in a tapered shape having a smaller diameter as approaching 8) and provided on the outer periphery of the distal end of the cylindrical portion (23 ₃ ).
8 engaging portion formed in a cylindrical shape so as to elastically fit in ₂₎ (27 _2), according to claim 3, characterized in that it is provided integrally with the outer peripheral portion of the elastic membrane (21 ₃₎ The vibration sound reducing device according to the above. 5. A piston (12) is slidably fitted.
Cylinder (13 ₁~ 13_Four) Cylinder
The engine body (E) including the block (11) is provided with the syringe
Da (13₁~ 13_Four) Surrounding the channel (14a)
A cooling water channel (14) including
(13)₁~ 13_Four) To the cooling in the cooling channel (14).
Vibration absorbing means for absorbing the vibration transmitted through the water
(16₁~ 16₆Of a water-cooled internal combustion engine equipped with
In the noise reduction device, the cooling water passage (14) has an inner end opened.
The pierced through hole (17₁, 17_Two) And the through hole (1
7 ₁, 17_Two)
The receiving portion (18) is connected to an outer wall portion (1) of the engine body (E).
1b), the through-hole (17)₁, 17_Two)
The closing member (1) attached to the outer wall (11b)
9₁~ 19₆), And one side faces the cooling water channel (14).
And the closing member (19₁~ 19₆) Between
The receiving portion with the other surface facing the space portion (20) formed.
(18) and the closing member (19)₁~ 19₆) Outer perimeter
Elastic membrane (21)₁~ 21_Three) And with vibration absorbing hands
Step (16₁~ 16₆) Is characterized by comprising
Vibration noise reduction device for cold internal combustion engines.