JP3461734B2 - Lubrication device relief valve - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a relief valve used for a lubrication device in an internal combustion engine or the like, and more particularly to a lubrication device suitably applicable to a lubrication device having an oil pump incorporated in a cylinder block. It relates to a relief valve of the device. 2. Description of the Related Art In the case of an oil pump which is generally provided independently, a relief valve used for a lubricating device for an internal combustion engine is provided in a relief valve mounting hole formed in a casing of the oil pump, and the internal combustion engine is made compact. In the case of an oil pump in which the rotor chamber is recessed in the front end surface of the cylinder block and built into the cylinder block, each part is assembled into the relief valve mounting hole provided in the cylinder block. It is configured. Referring to FIG. 4, reference numeral 21 denotes a relief valve mounting hole branched from an oil discharge passage (not shown) connected to an oil filter from a discharge chamber of an oil pump. Communication hole 22 for passage
And a mounting hole 24 having a larger diameter and a mounting screw 25 formed at a lower portion thereof. The communication hole 22 and the valve guide hole 23
A valve seat surface 26 is formed in a stepped portion therebetween, and a relief passage 27 is opened in a side surface of the valve guide hole 23. The relief valve 31 is an inverted cup-shaped valve body which is slidably fitted in the valve guide hole 23 and whose outer peripheral portion at the upper end is in close contact with the valve seat surface 26.
A mounting bolt 33 screwed into the mounting screw 25 of the mounting hole 24; and a compression spring 34 interposed between the valve body 32 and the mounting bolt 33 to press the valve body 32 toward the valve seat surface 26. It consists of. In the above construction, when the oil pressure in the oil discharge passage becomes equal to or higher than a predetermined pressure, the valve body 32 is pressed against the urging force of the compression spring 34 by the pressure.
The oil flows out of the relief passage 27 at a distance from the oil passage 6, and the oil pressure in the oil discharge passage is controlled within a certain pressure. When assembling the relief valve 31, the valve body 32 is inserted and fitted into the valve guide hole 23 of the relief valve mounting hole 21, and then the compression spring 34 is inserted. The mounting bolt 33 is screwed into the mounting screw 25 of the mounting hole 24 and fastened and fixed. However, in the configuration of the relief valve 31 as shown in FIG. 4, it is necessary to sequentially assemble the individual parts (three parts) as described above, resulting in poor workability. This is not a serious problem, especially when assembled in a separate oil pump casing in advance, but when assembled into a cylinder block to reduce the size of the internal combustion engine, such complicated steps are required during the assembly process of the engine body. Performing a proper assembling operation has a problem that workability is deteriorated. Therefore, as shown in FIG. 5, a relief valve 41 which is assembled in a single body in advance is constructed, and the relief valve 41 is inserted into the relief valve mounting hole 21 at the time of assembly.
It can be attached to This relief valve 41
, The valve case 42 is integrally fixed to the mounting bolt 33, and the valve guide hole 23 is
A communication opening 43 communicating with the communication hole 22 and a relief opening 44 communicating with the relief passage 27 are formed, and a step portion between the valve guide hole 23 and the communication opening 43 is provided with the valve seat surface 26.
And an O-ring 45 for sealing is arranged on the outer periphery between the communication opening 43 and the relief opening 44 of the valve case 42. It is necessary to form an annular groove 28 at a position corresponding to the relief passage 27 in the relief valve mounting hole 21 so that the relief opening 44 may be oriented in any direction when the relief valve 41 is mounted. However, in the relief valve 41 having the structure shown in FIG. 5, the provision of the valve case 42 complicates the structure, increases the cost, and reduces the cost.
If the O-ring 45 breaks, the oil will always leak from the communication hole 22 to the relief passage 27, so that the oil pressure will be reduced to about 20 to 30% of the predetermined pressure. However, there is a problem that quality assurance after assembly is difficult. SUMMARY OF THE INVENTION In view of the above-mentioned conventional problems, the present invention provides a relief device for a lubricating device which is assembled into a single unit, has good mounting workability, can be configured simply and inexpensively, and has a high operation quality after assembly. It is intended to provide a valve. According to the present invention, there is provided a relief valve for a lubricating apparatus, comprising: a mounting bolt fastened and fixed to a mounting screw formed in a relief valve mounting hole; A valve body that is fitted and can be brought into close contact with the valve seat surface provided at the back, and a compression spring that is interposed between the mounting bolt and the valve body and urges the valve body toward the valve seat surface The extension cylinder part is provided on the tip side of the mounting bolt, and the crimping part is provided at the tip thereof to be bent radially inward,
A state in which an engagement flange engageable with the caulking portion is formed on the outer periphery of the insertion end of the valve body into the extension cylindrical portion, and the mounting bolt and the valve body have a built-in compression spring at the caulking portion and the engagement flange. Since it is combined into a single body, the workability for mounting on the relief valve mounting hole is good, and since it consists of only three parts of the mounting bolt, the valve body and the compression spring, the number of parts is small and the configuration is simple. It can be configured at low cost, and the valve body is always tightly sealed to the valve seat surface of the relief valve mounting hole, so there is no risk of accidental oil leakage after assembly, and the operation quality after assembly is An effect such as high is obtained. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a relief valve of a lubricating apparatus according to the present invention will be described below with reference to FIGS. The relief valve of this embodiment is used for an oil pump built in a cylinder block, and is mounted in a relief valve mounting hole formed in the cylinder block. Therefore, prior to the description of the configuration of the relief valve itself, the configuration of the oil pump mounting portion and the relief valve mounting portion of the cylinder block will be described with reference to FIGS. In FIGS. 2 and 3, reference numeral 1 denotes a cylinder block, and a rotor chamber 4 of a trochoid type oil pump is recessed and formed at a position obliquely above one side of a bearing portion 3 of a crankshaft on a front end surface 2 thereof. Inner inner surface 4 of this rotor chamber 4
A discharge chamber 5 is formed in a substantially arc shape at an upper part of the upper part a, and a suction chamber 6 is formed in a substantially arc shape at a lower part. In the trochoid type oil pump, an outer rotor (not shown) is rotatably housed and arranged in a rotor chamber 4, and an inner rotor (not shown) is eccentrically arranged inside the outer rotor, and this inner rotor is interlocked with a crankshaft. By rotating and driving the driven shaft, a change in the space volume between the outer rotor and the inner rotor caused by the rotation causes the oil to be sucked from the suction chamber 6 and discharged toward the discharge chamber 5. I have. An oil discharge passage 7 is formed from the discharge chamber 5 toward the rear of the cylinder block 1 substantially in parallel with the crankshaft center, communicates with an oil filter (not shown), and is connected to the main gallery via the oil filter. It is connected.
A suction passage 8 is formed so as to communicate upward from the lower surface of the front end of the cylinder block 1 with the suction chamber 6, and a lower end opening of the suction passage 8 is immersed in oil in an oil pan (not shown). It is connected to the. A relief valve mounting hole 10 is formed upward from the lower side of the cylinder block 1 so as to be branched and connected in the middle of the oil discharge passage 7, and a relief valve 11 (see FIG. 1) is mounted. Then, the relief valve mounting hole 10 extends rearward from the suction chamber 6 substantially parallel to the crankshaft center.
The relief passage 9 is formed so as to communicate with the oil discharge passage 7, and a part of the oil in the oil discharge passage 7 is returned to the suction chamber 6 through the relief passage 9 when the relief valve 11 is opened. . Furthermore, this relief passage 9
In the lower position, the relief valve mounting hole 10 is
, A back pressure portion communication passage 9 a of the relief valve 11 is formed, and the back pressure portion of the relief valve 11 communicates with the suction chamber 6. The relief valve mounting hole 10 has a communicating hole 10a for the oil discharge passage 7, a valve guide hole 10b having a larger diameter than the communicating hole 10a, and a mounting screw 10d having a larger diameter and a lower portion thereof.
Is formed in the mounting hole 10c in which the communication hole 10a is formed.
A valve seat surface 12 is formed at the step between the valve guide hole 10b and the valve guide hole 10b. Further, the relief passage 9 is opened on the side surface of the valve guide hole 10b, and the back pressure communication passage 9a is opened above the mounting hole 10c. As shown in FIG. 1, the relief valve 11 is an inverted cup-shaped valve which is slidably fitted in the valve guide hole 10b and whose upper end outer peripheral portion is in close contact with the valve seat surface 12. Body 15, a mounting bolt 13 screwed into the mounting screw 10d of the mounting hole 10c, and a valve body 15 interposed between the valve body 15 and the mounting bolt 13.
Is formed by a compression spring 14 that presses the spring toward the valve seat surface 22. An extending cylindrical portion 16 is provided on the distal end side of the mounting bolt 13, and a caulking portion 17 that is bent radially inward at the distal end thereof is provided, and the outer periphery of the insertion end of the valve body 15 into the extending cylindrical portion 16 is provided. An engagement flange 18 that can be engaged with the crimping portion 17 is formed. At the time of assembling the relief valve 11, the compression spring 14 is inserted and arranged in the extending cylindrical portion 16 of the mounting bolt 13 and the valve body 15, and the valve body 15 is pressed from above to reduce the urging force of the compression spring 14. The lower end portion is pushed into the extension tube portion 16 in opposition, and the tip end portion of the extension tube portion 16 is crimped radially inward as shown by the arrow A in FIG. Can be. Thus, since the relief valve 11 is combined into a single body with the compression spring 14 built in by the engagement of the caulking portion 17 of the mounting bolt 13 and the engagement flange 18 of the valve body 15, the relief valve 11 At the time of mounting, the relief valve 11 can be mounted simply by inserting the relief valve 11 into the relief valve mounting hole 10 and screwing the mounting bolt 13 into the mounting screw 10d and fastening and fixing the relief valve 11 with good workability. be able to. Before mounting the relief valve 11, the caulking portion 17 and the engagement flange 18 are engaged as shown by the imaginary line in FIG. 1 (a). As shown in FIG.
As shown by a solid line in FIG.
2, the valve body 15 is pressed down against the urging force of the compression spring 14, and in this state, the valve body 15 is pressed against the valve seat surface 12 with a predetermined load by the compression spring 14, and the oil discharge passage 7 The pressure is maintained at a predetermined pressure. As described above, according to the relief valve 11 of the present embodiment, since only the three parts of the mounting bolt 13, the compression spring 14, and the valve body 15 are used, the number of parts is small and the configuration is simple. It can be configured at low cost. In addition, since the valve body 15 is always tightly sealed with the valve seat surface 12 of the relief valve mounting hole 10, there is no risk of accidental oil leakage after assembly and the operation quality after assembly is high. Is obtained. In the above description, the relief valve 1
Although the example in which the oil pump 1 is mounted in the relief valve mounting hole 10 formed in the cylinder block 1 has been described, it can be mounted in a relief valve mounting hole formed in an independent oil pump casing, and the same effect can be obtained. Needless to say. According to the relief valve of the lubricating device of the present invention, as described above, the mounting bolt and the valve body are combined into a single body with the compression spring built in by the caulked portion and the engagement flange. Therefore, the mounting workability to the relief valve mounting hole is good, and since it is composed of only three parts, namely, the mounting bolt, the valve body, and the compression spring, the number of parts is small and the configuration is simple. Also, the valve body is always tightly sealed to the valve seat surface of the relief valve mounting hole, so there is no risk of accidental oil leakage after assembly, and effects such as high operation quality after assembly are obtained. be able to.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows an embodiment of a relief valve of a lubricating device according to the present invention, wherein (a) is a sectional view of the relief valve itself,
(B) is a cross-sectional view of a state where it is mounted in a relief valve mounting hole. FIG. 2 is a front view showing a main structure of a cylinder block to which the relief valve according to the embodiment is mounted. FIG. 3 is a sectional view taken along the line BB of FIG. 2; FIG. 4 is a sectional view of a conventional relief valve. FIG. 5 is a cross-sectional view of a configuration example of a relief valve which solves a problem of the conventional relief valve. [Description of Signs] 1 Cylinder block 10 Relief valve mounting hole 11 Relief valve 12 Valve seat surface 13 Mounting bolt 14 Compression spring 15 Valve body 16 Extended cylinder portion 17 Caulked portion 18 Engagement flange

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁷ , DB name) F01M 1/16 F16K 17/04

Claims (1)

(57) [Claim 1] A mounting bolt fastened and fixed to a mounting screw formed in a relief valve mounting hole, and slidably fitted in the relief valve mounting hole and provided in a back portion. A valve body that can be in close contact with the valve seat surface, and a compression spring that is interposed between the mounting bolt and the valve body and urges the valve body toward the valve seat surface. An extension cylinder is provided and a caulking portion is provided at the tip of the extension to be bent radially inward,
A relief valve for a lubricating device, wherein an engagement flange is formed on an outer periphery of an insertion end of the valve body into an extension cylinder portion, the engagement flange being engageable with a caulking portion.