JP2009185637A - Attachment structure of guide pipe of oil level gage - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To simplify an attachment structure of a guide pipe of an oil level gage. <P>SOLUTION: The attachment structure 24 of the guide pipe 22 is provided with a first section 30, an attachment member 40, and a second section 50. The first section 30 is provided in a crank case 18, and includes an attachment hole 34 and a support part 35 projecting toward an inside of an attachment surface 34 from an inner circumference surface 34b of the attachment hole 34. The attachment member 40 supports the guide pipe 22 to the crank case 18 and is disposed in the attachment hole 34. The second section 50 is provided in the crank case 18 and is fixed to the first section 30 so as to sandwich a part of the attachment member 40 between the support part 35 and the same. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an attachment structure, and more particularly to a structure for attaching a guide tube for guiding an oil level gauge to a casing.

  An oil level gauge is inserted into the internal combustion engine in order to check the remaining amount of oil in the automobile internal combustion engine. The oil level gauge is guided by a guide tube attached to a cylinder block of the internal combustion engine.

  2. Description of the Related Art Conventionally, a structure in which a mounting flange portion is provided on one end side of a guide pipe is known as a guide pipe mounting structure of this type of oil level gauge. An annular seal member made of an elastic body is provided on the distal end side of the mounting flange portion (see, for example, Patent Document 1).

In this mounting structure, an annular seal member is fitted into a mounting hole provided in the cylinder block. With such a configuration, even when the mounting angle of the guide tube is slightly inclined, the inclination is absorbed by the elasticity of the seal member, and the sealing performance in the cylinder block can be maintained.
Japanese Patent Laid-Open No. 9-291811

  However, in the conventional structure, in order to prevent the guide tube from falling off from the mounting hole of the cylinder block, the mounting flange portion of the guide tube is fixed to the cylinder block with a bolt or the like. For this reason, the guide tube mounting structure tends to be complicated.

  An object of the present invention is to simplify an oil level gauge guide tube mounting structure.

  An attachment structure according to the present invention is a structure in which a guide tube for guiding an oil level gauge is attached to a casing of an internal combustion engine, and includes a first portion, an attachment member, and a second portion. The first portion is a portion provided in the casing, and includes a mounting hole and a contact portion that protrudes from the inner surface of the mounting hole toward the mounting hole. The mounting member supports the guide tube with respect to the casing and is disposed in the mounting hole. The second part is a part provided in a member provided in the casing, and is fixed to the first part so that at least a part of the attachment member is sandwiched between the second part and the contact part.

  In this attachment structure, since the attachment member is sandwiched between the contact portion and the second portion, a member for preventing the attachment member from being detached becomes unnecessary, and the structure can be simplified.

  Since the oil level gauge guide tube mounting structure according to the present invention has the above-described configuration, the structure can be simplified.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
<Overall configuration of transmission>
An internal combustion engine 10 in which an embodiment of the present invention is employed will be described with reference to FIG. FIG. 1 is a schematic front view of the internal combustion engine 10.

  The internal combustion engine 10 includes, for example, a cylinder block 12 manufactured by casting, a cylinder head 14 disposed on the upper portion of the cylinder block 12, a head cover 15 disposed on the upper portion of the cylinder head 14, and a lower portion of the cylinder block 12. An oil pan 16 (an example of a casing). The cylinder block 12 and the oil pan 16 form a crank chamber 19 in which the crankshaft 41 is disposed. Oil is stored in the oil pan 16.

  In this embodiment, the cylinder block 12 includes a cylinder part 17 in which a plurality of cylinders (not shown) are formed, a crankcase 18 (an example of a casing) in which the crankshaft 11 is fixed and fixed to the cylinder part 17, have. Flange portions 17a and 18a are formed in the cylinder portion 17 and the crankcase 18 in order to join each other with bolts. Flange portions 18b and 16a are formed in the crankcase 18 and the oil pan 16 to join each other with bolts.

  The internal combustion engine 10 is provided with a timing chain 44 for driving the crankshaft 41 and the two cam shafts 42a and 42b in synchronization. The internal combustion engine 10 is provided with a drive chain 48 for driving an oil pump 46 that supplies oil.

  A guide tube 22 for guiding the oil level gauge 20 is attached to the cylinder block 12 of the internal combustion engine 10.

  The oil level gauge 20 includes a handle portion 20 a that is fitted into the upper end of the guide tube 22, and a gauge portion 20 b that protrudes from the lower end of the guide tube 22 and is disposed inside the oil pan 16. The gauge part 20b is a plate-shaped member, for example.

  The guide tube 22 is a member that guides the oil level gauge 20, and is made of, for example, a metal tube. As shown in FIG. 2, the guide tube 22 is formed by slightly bending the pipe, and is disposed so as to be entirely inclined with respect to the flange portion 18b. The guide tube 22 is attached to the flange portion 18b of the crankcase 18 by an attachment structure 24 (described later).

<Guide tube mounting structure>
As shown in FIG. 2, the guide tube 22 mounting structure 24 is provided on the first portion 30 provided on the flange portion 18 b of the crankcase 18, the mounting member 40, the fixed tube 23, and the oil pan 16 16 b. Second portion 50 formed.

(1) 1st part The 1st part 30 is a part of the front side (for example, oil pump 46 periphery) of the flange part 18b, and has the attachment hole 34 and the support part 35. As shown in FIG. The attachment hole 34 penetrates from the inside to the outside of the flange portion 18b. The inside of the flange portion 18b means the crank chamber 19 side of the flange portion 18b. In this embodiment, the attachment hole 34 is formed in a cylindrical shape.

  The support portion 35 is formed so as to protrude from the inner peripheral surface 34 b (an example of the inner surface) of the attachment hole 34 to the inside of the attachment hole 34, and is disposed at a position closest to the opposite side (outer side) of the crank chamber 19. Has been. The support portion 35 is an annular portion and has a support surface 35 a and an opening 32. In this embodiment, the support surface 35a is an annular surface, and the opening 32 is circular. The opening 32 has an inner peripheral surface 32a. Through the opening 32, a space formed on the inner peripheral side of the inner peripheral surface 34b and a space outside the crankcase 18 communicate with each other. A fixed tube 23 is inserted into the opening 32. An attachment member 40 is fitted in the attachment hole 34, and the support surface 35a is in contact with the attachment member 40 so that the attachment member 40 does not come out.

(2) Attachment Member As shown in FIGS. 2 and 3, the attachment member 40 is a cylindrical member made of an elastic body such as a synthetic rubber material having heat resistance, for example, and the metal first portion 30 and The rigidity is lower than that of the second portion 50 made of resin. The mounting member 40 is opposed to the outer peripheral surface 40d, the generally annular contact surface 40a that contacts the support surface 35a of the mounting hole 34, the fixed hole 40b that penetrates downward from the contact surface 40a, and the contact surface 40a. And a generally annular bottom surface 40c.

  The support surface 35a and the bottom surface 40c are arranged substantially in parallel. The support surface 35 a is disposed substantially parallel to the outer surface 30 b of the first portion 30. The fixing hole 40b is inclined with respect to the contact surface 40a and the bottom surface 40c.

  In consideration of sealing properties, the outer diameter of the mounting member 40 is slightly larger than the inner diameter of the mounting hole 34. The attachment member 40 is press-fitted and fixed in the attachment hole 34 and is elastically deformed in the attachment hole 34. Due to this elastic force, the outer peripheral surface 40 d of the mounting member 40 is in close contact with the inner peripheral surface 34 b of the mounting hole 34. A part of the attachment member 40 is sandwiched between the support portion 35 and the second portion 50 so that the attachment member 40 does not fall off inside the flange portion 18b.

(3) Fixed tube The fixed tube 23 is a tubular member shorter than the guide tube 22, and is made of, for example, a synthetic resin. The attachment member 40 is integrally formed with the fixed tube 23 by, for example, outsert molding. Thereby, the fixed tube 23 is firmly fixed to the mounting member 40. The first end 23 a of the fixed tube 23 is fixed to the attachment member 40. The second end portion 23b of the fixed tube 23 is fixed to the lower end portion 22a of the guide tube 22 by adhesion or press fitting. Since the fixed tube 23 is inserted into the opening 32, the fixed portion between the guide tube 22 and the fixed tube 23 is disposed outside the crankcase 18.

  Since the fixing hole 40b in which the fixed tube 23 is fitted is inclined with respect to the contact surface 40a, the fixed tube 23 is fixed to the mounting member 40 in a state inclined with respect to the contact surface 40a. The state where the fixed hole 40b is inclined with respect to the contact surface 40a means, for example, a state where the central axis of the fixed hole 40b is inclined with respect to the contact surface 40a. Since the support surface 35a and the outer surface 30b of the first portion 30 are arranged substantially in parallel, the fixed tube 23 is also inclined with respect to the outer surface 30b. Thereby, in the state where the contact surface 40a is in contact with the support surface 35a, the fixed tube 23 and the guide tube 22 are inclined with respect to the support surface 35a and the outer surface 30b.

(4) 2nd part As shown in FIG. 2, the 2nd part 50 is a part of flange part 16a of the oil pan 16 (an example of the member attached to a casing), and has the contact surface 50a. The contact surface 50 a is in contact with the bottom surface 40 c of the mounting member 40. A part of the attachment member 40 is sandwiched between the contact surface 50 a and the support portion 35. Thereby, it is possible to prevent the attachment member 40 from dropping out of the attachment hole 34.

  Further, since the thickness dimension of the attachment member 40 is substantially the same as or slightly smaller than the depth dimension of the attachment hole 34, the attachment member 40 is held between the first portion 30 and the second portion 50. Thereby, the contact surface 40 a of the mounting member 40 is in close contact with the support surface 35 a of the mounting hole 34, and the bottom surface 40 c of the mounting member 40 is in close contact with the contact surface 50 a of the second portion 50.

<Guide tube installation procedure>
When the guide tube 22 is attached to the crankcase 18 of the cylinder block 12, the attachment member 40 is attached from the inner surface 30 a side of the first portion 30 until the contact surface 40 a contacts the support surface 35 a of the attachment hole 34. 34 and press fit. At this time, since the outer diameter of the mounting member 40 is slightly larger than the inner diameter of the mounting hole 34, the outer peripheral surface 40 d of the mounting member 40 is in close contact with the inner peripheral surface 34 b of the mounting hole 34. Thus, even when a small depression (so-called nest) is formed on the inner peripheral surface 34b of the mounting hole 34 of the first portion 30 during casting, the portion is blocked by the mounting member 40 and the sealing performance can be maintained.

  Further, when the attachment member 40 is attached to the attachment hole 34, the contact surface 40a of the attachment member 40 contacts the support surface 35a of the support portion 35, so that the attachment member 40 can be prevented from coming out of the flange portion 18b. .

  When the attachment member 40 is mounted in the attachment hole 34, the guide tube 22 is fixed to the fixed tube 23 by press-fitting or bonding.

  In the assembly operation of the internal combustion engine 1, the oil pan 16 is attached to the crankcase 18. Specifically, the flange portions 16a and 18b are fixed with bolts in a state where the flange portions 16a and 18b are combined. At this time, since a part of the attachment member 40 is sandwiched between the second portion 50 and the attachment hole 34 of the first portion 30, it is possible to prevent the attachment member 40 from dropping from the attachment hole 34.

<Features>
The features of the mounting structure 24 are as follows.

(1)
In the mounting structure 24, the mounting member 40 is disposed in the mounting hole 34 of the first portion 30, and the mounting member 40 is sandwiched between the support portion 35 and the second portion 50 of the first portion 30. The attachment member 40 can be prevented from falling out of the attachment hole 34. For this reason, a member for preventing the attachment member 40 from being detached becomes unnecessary, and the structure can be simplified.

  Further, since the attachment member 40 can be attached simply by being fitted into the attachment hole 34, the attachment operation can be simplified and the manufacturing cost can be reduced.

Furthermore, if the mounting structure 24 is simplified, the mounting structure 24 can be downsized, and thus the internal combustion engine 10 can be expected to be downsized.
Further, when the attachment member 40 is attached to the attachment hole 34, the contact surface 40a of the attachment member 40 contacts the support surface 35a of the support portion 35, so that the attachment member 40 can be prevented from coming out of the flange portion 18b. .

(2)
The attachment member 40 has lower rigidity than the first portion 30 and the second portion 50, and the attachment member 40 is fitted in the attachment hole 34. For this reason, the outer peripheral surface 40d of the mounting member 40 is in close contact with the inner peripheral surface 34b of the mounting hole 34, and sealing performance can be ensured.

  Further, since the attachment member 40 is a member (elastic body) having rigidity lower than that of the first portion 30 and the second portion 50, even if vibration is transmitted from the crankcase 18 to the attachment member 40, the vibration is low rigidity. It is attenuated by the mounting member 40.

(3)
Since the mounting member 40 is made of an elastic body such as synthetic rubber, when the surface of the inner peripheral surface 34b of the mounting hole 34 is rough, or the size of the mounting hole 34 and the size of the mounting member 40 are slightly different from the design dimensions. Even in this case, the outer peripheral surface 40d of the mounting member 40 is in close contact with the inner peripheral surface 34b, and the sealing performance can be ensured.

(4)
Since the support part 35 has the support surface 35a, the attachment member 40 can be positioned by the contact surface 40a contacting the support surface 35a. Further, by bringing the contact surface 40a into contact with the support surface 35a, the posture of the attachment member 40 with respect to the first portion 30 is further stabilized, and the sealing performance by the attachment member 40 is further improved.

(5)
This attachment structure 24 has a fixed tube 23 formed integrally with the attachment member 40. The fixed tube 23 extends to the outside of the flange portion 18 b through the opening 32, and the guide tube 22 is fixed to the fixed tube 23. Thereby, vibration transmitted from the crankcase 18 to the guide tube 22 is absorbed by the mounting member 40, and transmission of vibration from the crankcase 18 to the guide tube 22 can be suppressed.

(6)
The fixed tube 23 is inclined with respect to the outer surface 30 b of the first portion 30. Thereby, the oil level gauge 20 can be smoothly guided to a deep position in the oil pan 16.

(7)
The attachment member 40 has a contact surface 40a that contacts the support surface 35a, and the guide tube 22 is provided so as to be inclined with respect to the contact surface 40a. For this reason, even if it does not form in the state which inclined the attachment hole 34 with respect to the flange part 18b, the guide tube 22 can be arrange | positioned so that it may incline to the outer surface 30b of the flange part 18b. Thereby, the manufacturing cost can be reduced.

<Other embodiments>
The specific configuration of the present invention is not limited to the above-described embodiment, and various changes and modifications can be made without departing from the scope of the invention.

(A)
In the above-described embodiment, a gap is formed between the opening 32 and the fixed tube 23. The present invention is not limited to this, and as shown in FIGS. 4 and 5, the insertion member 140 d inserted into the opening 32 may be formed in a step shape in the attachment member 140. In addition, since structures other than those described below are substantially the same as those in the above-described embodiment, description thereof is omitted.

  4 and 5, the insertion portion 140 d is formed so as to protrude from the contact surface 140 a of the attachment member 140. In this embodiment, the outer peripheral surface 140e of the insertion portion 140d is in contact with the inner peripheral surface 32a of the opening 32. The fixing hole 140b is longer than the above-described fixing hole 40b by the amount provided for the insertion portion 140d. A slight gap may be provided between the inner peripheral surface 32a of the opening 32 and the insertion portion 140d.

  As described above, by providing the attachment member 140 with the insertion portion 140d inserted into the opening 32, the posture of the attachment member 140 with respect to the first portion 30 is further stabilized. Further, the sealing portion can be further enhanced by the insertion portion 140d being in contact with the inner peripheral surface 32a of the opening 32.

(B)
In the above-described embodiment, the synthetic rubber material is used for the attachment members 40 and 140. However, the attachment members 40 and 140 may be synthetic rubber as long as they have lower rigidity and sealability than the first and second portions 30 and 50. It is not limited to an elastic body such as a material. For example, synthetic resin may be used as the attachment members 40 and 140.

(C)
In the above-described embodiment, the fixing tube 23 is integrally formed with the mounting member 40 by outsert molding, but may be fixed by other fixing methods such as adhesion or press-fitting. Further, the guide tube 22 may be directly fixed to the mounting members 40 and 140 without providing the fixed tube 23.

  (D) In the above-described embodiment, the fixing tube 23 of the guide tube 22 is formed integrally with the mounting member 40 in advance, and then the mounting member 40 is fitted into the mounting hole 34. However, the mounting member 40 is fitted into the mounting hole. The guide tube 22 may be fixed to the mounting member 40.

(E)
In the above-described embodiment, the guide tube 22 is made of a metal tube and the fixed tube 23 is made of a synthetic resin. However, the material of the guide tube 22 and the fixed tube 23 is not limited to the above-described embodiment. For example, the material of the guide tube 22 and the fixed tube 23 may be made of metal or synthetic resin.

(F)
In the above-described embodiment, the attachment member 40 can be prevented from rotating only by fitting the attachment member 40 made of an elastic body into the attachment hole 34. However, in order to reliably prevent the attachment member 40 from rotating, a rotation preventing structure may be employed. FIG. 6 is a plan view of the attachment member 240 when viewed from the crank chamber 19.

  As shown in FIG. 6, for example, an anti-rotation recess 234 c is formed on the inner peripheral surface 234 b of the attachment hole 234. On the outer peripheral surface of the mounting member 240, a rotation prevention convex portion 240d fitted into the rotation prevention concave portion 234c is formed. The rotation of the mounting member 240 relative to the first portion 230 is restricted by the rotation stopper recess 234c and the rotation prevention protrusion 240d.

  The anti-rotation structure is not limited to such a structure. For example, the anti-rotation recess 234c may be provided in the attachment member 240, and the anti-rotation protrusion 240d may be provided in the attachment hole 234, respectively. Further, the anti-rotation structure may be realized by making the planar shape of the attachment hole 234 and the attachment member 240 into a non-circular shape such as an oval or a rectangle.

(G)
The shape of the support part 35 is not limited to the above-mentioned embodiment. For example, the support portion 35 may be at least one protrusion that extends radially inward from the inner peripheral surface 34 b of the attachment hole 34.

(H)
The guide tube mounting structure according to the present invention can be applied to all internal combustion engines having a structure capable of storing oil.

  Since the structure of the guide tube mounting structure according to the present invention can be simplified, the present invention is useful in the field of internal combustion engines.

1 is a schematic side view of an internal combustion engine. The cross-sectional enlarged view of the attachment structure of a guide tube. The perspective view of an attaching part. Sectional enlarged view of the guide tube mounting structure (another embodiment). The perspective view of an attaching part (other embodiments). Sectional enlarged view of the guide tube mounting structure (another embodiment).

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Internal combustion engine 12 Cylinder block 16 Oil pan (an example of a casing)
18 Crankcase (example of casing)
20 Oil level gauge 22 Guide tube 23 Fixed tube 24 Mounting structure 30 1st part 30b Outer side surface 32 Opening 34 Mounting hole 34b Inner peripheral surface (inner side surface)
35 support portion 35a support surface 40, 140, 240 mounting member 40a contact surface 40b fixing hole 50 second portion 140d insertion portion

Claims (8)

A structure in which a guide pipe for guiding an oil level gauge is attached to a casing of an internal combustion engine,
A first portion having a mounting hole and a support portion projecting from an inner surface of the mounting hole toward the mounting hole;
An attachment member that supports the guide tube with respect to the casing and is disposed in the attachment hole;
A portion provided in a member attached to the casing, the second portion fixed to the first portion so as to sandwich at least a part of the attachment member between the support portion,
Oil level gauge guide tube mounting structure with The mounting member has lower rigidity than the first portion and is fitted in the mounting hole.
The oil level gauge guide tube mounting structure according to claim 1. The mounting member is made of an elastic body.
An oil level gauge guide tube mounting structure according to claim 1 or 2. The support portion has a support surface with which the mounting member abuts.
The oil level gauge guide tube mounting structure according to any one of claims 1 to 3. The support portion has an opening that allows communication between the space in the mounting hole and the space outside the first member;
The mounting member has an insertion portion that is inserted into the opening.
An oil level gauge guide tube mounting structure according to any one of claims 1 to 4. The guide tube is inclined with respect to the outer surface of the first portion;
The oil level gauge guide tube mounting structure according to any one of claims 1 to 5. The mounting member has a contact surface that contacts the support surface;
The guide tube is provided so as to be inclined with respect to the contact surface.
The oil level gauge guide tube mounting structure according to claim 4. A fixing pipe formed integrally with the mounting member and extending to the outside of the casing through the opening;
The guide tube is fixed to the fixed tube;
4. An oil level gauge guide tube mounting structure according to claim 2 or 3.

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