JPH0566244U - Camshaft bearing cap - Google Patents

Abstract

(57) [Summary] [Purpose] To increase the rigidity of the camshaft bearing cap. A cam cap 10a is mounted and fixed on a cam journal provided on an overhead cam type cylinder head 11, and each cam cap 10a pivotally supports a cam shaft.
A cover 10b that covers the upper side of the cam shaft is integrally formed between a and formed, and a portion 10c 'of the side wall 10c that interferes with the cylinder head bolt is bulged outward to form a hole 10d through which the cylinder head bolt can freely pass. It has a perforated structure.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a camshaft bearing cap for a cylinder head.

[0002]

[Prior Art]

 As shown in FIG. 4, a cam shaft 1 of an overhead cam (OHC) type engine valve mechanism has a cam journal 3 provided with a journal portion (not shown) on a cylinder head 2, and a cam journal 3 mounted on the cam journal 3. It is rotatably supported by a cam cap 4 which is fixed and fixed. The camshaft 1 is supported by the cylinder head 2 at a plurality of places via journal portions provided at a plurality of places. With the rotation of the engine, oil is supplied to each sliding surface between each journal of the cam shaft 1 and the cam journal of the cylinder head 2, and between each cam 1a and each rocker arm. It is supposed to be lubricated.

However, as the engine speed increases, the amount of oil supplied to the valve operating system increases, and as a result, a large amount of oil attached to the cam 1a scatters due to centrifugal force and becomes fine particles inside the rocker cover. Fill up. On the other hand, the blow-by gas leaked into the rocker cover is returned to the intake system by the engine negative pressure and is burned again. At this time, the fine particles of the oil filled in the rocker cover are easily carried away together with the blow-by gas, the consumption of the oil is increased accordingly, and the oil is easily deteriorated because it comes into contact with the blow-by gas. There is a problem that the exhaust gas purification performance of the engine is deteriorated by the oil and the parts are contaminated.

Therefore, the present applicant has previously provided a cover 5b for covering the upper side of the cam 1a integrally with a cam cap 5a that pivotally supports the cam shaft 1 in cooperation with the cam journal 3 as shown in FIG. We have proposed a cam cap 5 designed to prevent the oil from splashing. The oil that is scattered upward from the cam by the centrifugal force as the camshaft 1 rotates and is made into fine particles is taken into the cover 5b of the cam cap 5 and attached to the inner surface thereof, or collects in the cover 5b to form large particles. It turns into and falls. This makes it difficult for the scattered oil to come into contact with the blow-by gas, preventing deterioration of the oil due to the blow-by gas, and making it difficult for the oil to be carried away with the blow-by gas, thus reducing the consumption of oil.

[0005]

[Means for Solving the Problems]

 By the way, as shown in FIGS. 6 and 7, the cam cap 5 has a cover 5b with a notch 5c corresponding to the position of each cylinder head bolt in order to avoid interference with the tightening tool 7 of the cylinder head bolt 6. It is provided. However, if the notch 5c is provided in the cover 5b, the rigidity of the cover 5b that connects the adjacent cam caps 5b, 5b is significantly impaired, and the connecting rigidity becomes low.

The present invention has been made in view of the above points, and an object thereof is to provide a camshaft bearing cap that avoids interference with a tightening tool for a cylinder head bolt and ensures rigidity. To do.

[0007]

[Means for Solving the Problems]

 In order to achieve the above object, according to the present invention, each of the cam caps mounted and fixed on the cam journal provided in the overhead cam type cylinder head and cooperating with the cam journal to pivotally support the cam shaft. A cover that covers the upper side of the cam shaft is integrally formed between the cam caps, and a portion of the side wall of the cover that interferes with the cylinder head bolt is bulged outward so that the cylinder head bolt can freely penetrate. The structure has holes.

[0008]

[Action]

 The camshaft bearing caps are mounted by bolts, with each cam cap resting on each corresponding cam journal on the cylinder head. A cam shaft is rotatably supported between the cam journal and the cam cap. The cover connecting the cam caps of the camshaft bearing cap continuously covers the camshaft. In this state, the hole provided in the cover corresponds to the cylinder head bolt hole, and the cylinder head bolt and the tightening tool for tightening the bolt allow play without interference.

[0009]

【Example】

 An embodiment of the present invention will be described in detail below with reference to the accompanying drawings. 1 to 3, the camshaft bearing cap 10 is formed integrally with the adjacent cam caps 10a and 10a by a cover 10b and is integrally formed over the entire length of the cylinder head 11. The side wall 10c on the head bolt hole 11a side is formed with a portion 10c 'corresponding to the bolt hole 11a bulging outward, and each has a hole 10d having a predetermined diameter.

The hole 10d is set to a size such that the head portion 13a of the cylinder head bolt 13 and the tightening tool 14 for the bolt 13 can freely penetrate with a slight gap. That is, in the camshaft bearing cap 10, the portion of the cover 10b that interferes with the cylinder head bolt 13 and the tightening tool 14 is continuously formed as a hole without being cut out. The camshaft bearing cap 10 having such a shape is integrally formed.

The operation will be described below. As shown in FIG. 1, a camshaft bearing cap 10 is disposed on a cylinder head 11 of an engine, and each cam cap 10a is mounted on each corresponding cam journal (not shown) of the cylinder head 11, The bolts 12 are firmly tightened and fixed. A cam shaft (not shown) is rotatably supported between the two. In this state, the upper part of the camshaft is surrounded by the camshaft bearing cap 10. Further, the hole 10d of each cover 10b of the camshaft bearing cap 10 corresponds to the bolt hole 11a of the cylinder head bolt 13 formed in the cylinder head 11.

The cylinder head bolt 13 is loosely inserted through the hole 10d of each cover 10b with a slight gap (FIG. 2), and is screwed into the bolt hole 11a of the cylinder head 11. Next, the tip of the tightening tool 14 loosely penetrates the hole 10d with a slight clearance, and the cylinder head bolt 13 is tightened. The camshaft bearing cap 10 has a hole 10d at a portion of the cover 10b that continuously connects the cam caps 10a, which interferes with the cylinder head bolt 13, the tightening tool 14, etc. Is high and therefore is firmly fixed to the cylinder head 11.

[0013]

[Effect of the device]

 As described above, according to the present invention, the portion of the side wall of the cover, which is integrally connected to each cap and covers the upper side of the cam, interferes with the cylinder head bolt and the tightening tool and is bulged outward. By forming a hole through which the head bolt and the tightening tool can freely pass, interference with the cylinder head bolt of the cover and the tightening tool of the bolt can be avoided, and the joint rigidity of the cover can be improved. The effect is that it can be raised.

[Brief description of drawings]

FIG. 1 is a partial plan view of a cylinder head to which a camshaft bearing cap according to the present invention is applied.

FIG. 2 is a sectional view taken along the line II-II in FIG.

3 is a partial perspective view of the camshaft bearing cap of FIG.

FIG. 4 is a partial side view of a conventional camshaft.

FIG. 5 is a partially cutaway side view of a conventional cylinder head in which a cam cap having a cover for covering the upper side of the cam shaft is mounted.

6 is a partial perspective view of the camshaft bearing cap of FIG.

7 is a cross-sectional view taken along the arrow VII-VII in FIG.

[Explanation of symbols]

 10 Camshaft Bearing Cap 10a Cam Cap 10b Cover 10c Side Wall 10d Bolt Insertion Hole 11 Cylinder Head 13 Shander Head Bolt 14 Tightening Tool

Claims (1)

[Scope of utility model registration request] 1. An overhead cam type cylinder head is mounted and fixed on a cam journal, which cooperates with the cam journal to pivotally support the cam shaft. A cover for covering is integrally formed continuously, and a portion of a side wall of the cover that interferes with the cylinder head bolt is bulged outward to form a hole through which the cylinder head bolt can freely pass. Camshaft bearing cap to be used.