JPH056104U - Camshaft support bearing device for internal combustion engine - Google Patents

Abstract

(57) [Abstract] [Purpose] To reduce the rotational resistance of the camshaft and improve the performance of the internal combustion engine. [Structure] A raceway groove 1a for a ball 8 is formed on an outer peripheral surface of the shaft portion of a camshaft 1, and a base 3 of a cylinder head is formed.
And a bearing cap 4 for holding the camshaft 1 with respect to the pedestal 3, two outer races 6a, 6b are attached, and the raceway grooves of the pair of half-divided outer races 6a, 6b and the raceway groove of the camshaft 1 are attached. 1a and the cage 7a divided in two,
A ball 8 is rotatably held by 7b. As a result, the rotation resistance of the camshaft 1 is significantly reduced compared to the conventional example in which the slide bearing is used, and operation with less loss is possible, and high fuel consumption, high rotation and high output can be achieved. It will also be.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a camshaft support bearing device for an internal combustion engine.

[0002]

[Prior Art]

 Conventionally, a camshaft of an internal combustion engine is rotatably supported at a predetermined position of a cylinder head through a slide bearing such as metal.

[0003]

[Problems to be solved by the device]

 In recent years, there has been an increasing demand for performance improvements such as reduction of horsepower loss and improvement of fuel efficiency in internal combustion engines.

By the way, in the conventional internal combustion engine, since the camshaft is supported by the slide bearing as described above, it is considered that the rotation resistance of the camshaft is large, and there is room for improvement here.

The present invention has been made in view of such circumstances, and an object thereof is to reduce the rotational resistance of the camshaft and improve the performance of the internal combustion engine.

[0006]

[Means for Solving the Problems]

 In order to achieve such a subject, the present invention provides a camshaft support bearing that rotatably supports a shaft portion between cam portions provided at predetermined intervals in a longitudinal direction of a camshaft on a receiving portion of a cylinder head. The device has the following configuration.

A camshaft supporting bearing device for an internal combustion engine according to the present invention forms a raceway groove for a ball on an outer peripheral surface of the shaft portion of the camshaft, and a receiving portion for the cylinder head and a receiving portion for the receiving portion. A two-piece outer ring is attached between the camshaft and the mounting member that holds the camshaft, and the two-piece cage is used to rotate between the track of the pair of half-divided outer rings and the track groove of the camshaft. It is characterized in that it holds balls to be held.

[0008]

[Action]

 Since the camshaft is supported by the ball bearing, the rotation resistance of the camshaft is smaller than that of the conventional sliding bearing.

In particular, when mounting the ball bearing on the shaft portion between the cam portions of the camshaft, since the cam portions are present on both sides of the shaft portion, the ball bearing having the two-division structure is used. Bearings can be installed. Also, as the inner ring of the ball bearing, by forming a ball raceway groove in the camshaft and using the camshaft as a substitute, it is possible to mount the ball bearing in a small space between the camshaft and the receiving part of the cylinder head. There is.

[0010]

【Example】

 Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

1 to 4 show an embodiment of the present invention. In the figure, 1 is a camshaft provided with cam portions 2 at predetermined intervals in the longitudinal direction, 3 is a pedestal (receiving portion) provided on a cylinder head (not shown), and 4 is a camshaft 1 held on the pedestal 3. The bearing caps (mounting members) 5 are ball bearings interposed between the pedestal 3 and the bearing cap 4.

The ball bearing 5 is rotated into two halved outer rings 6a and 6b, two halved resin cage holders 7a and 7b, and pockets 9 of the cage holders 7a and 7b. It consists of a ball 8 that is held freely. At the outer diameter side openings of the pockets 9 of the half cages 7a and 7b, there are claws 9a at the inner diameter side openings of the respective pockets 9 for preventing the balls 8 projecting in the circumferential direction from coming out to the outer diameter side. Each of the flanges 9b is provided to prevent the balls 8 from coming out toward the inner diameter side. The material of the balls 8 is appropriately selected from ceramics or bearing steel.

A raceway groove 1 a of a ball 8 is formed in the shaft portion between the cam portions 2 of the camshaft 1, and a ball bearing 5 is mounted on the outer periphery of the raceway groove 1 a and supported by the pedestal 3. It is becoming like this.

A semi-annular groove 11 for fitting one half outer ring 6 a of the ball bearing 5 therein is formed at both axial end portions of the outer peripheral surface of the pedestal 3, and the inner peripheral surface of the bearing cap 4 is formed. A semi-annular groove 12 for internally fitting the other half-split outer ring 6b of the ball bearing 5 is formed at both ends in the axial direction, and the bearing cap 4 is attached to the pedestal 3 by a bolt. The split surfaces of the half-divided outer rings 6a, 6b are arranged so as not to coincide with the fitting surface between the pedestal 3 and the bearing cap 4. The half outer ring 6b is secured to the bearing cap 4 by the following means. The anti-rotation means includes a bottomed hole 13 provided at a predetermined position on the outer circumference of the half-divided outer ring 6b, an unquenched steel ball 14 press-fitted into the bottomed hole 13 so as to partially project, and a bearing. The cap 4 includes a recess 15 provided at a predetermined position of the semi-annular groove 12 and engaged with a protruding portion of the steel ball 14.

According to this structure, the camshaft 1 is supported by the ball bearing 5 in a rolling manner to rotate, so that the rotation resistance is greatly reduced compared to the conventional example in which the slide bearing is used. As a result, the rotational load of the internal combustion engine is reduced and efficient operation is possible, and higher rotation and higher output can be achieved.

[0016]

[Effect of the device]

 As described above, according to the present invention, since the cam shaft is rollingly supported by the ball bearing, the rotational resistance of the cam shaft is greatly reduced as compared with the conventional example in which the slide bearing is used. In other words, since the rotational load of the internal combustion engine is reduced, it is possible to operate with less loss, improve fuel efficiency, and achieve high rotation and high output. Contribute to improvement.

[Brief description of drawings]

FIG. 1 is a sectional view showing a supporting portion of a camshaft according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a plan view showing a pocket of a cage.

FIG. 4 is a sectional view taken along line BB of FIG.

[Explanation of symbols]

1 Camshaft 2 Cam part of camshaft 3 Pedestal 4 Bearing cap 5 Ball bearing 6a, 6b Half outer ring 7a, 7b Half retainer 8 Ball 1a Orbit groove of camshaft

Claims (1)

Claims for utility model registration 1. A camshaft support bearing device for rotatably supporting a shaft portion between cam portions provided at predetermined intervals in a longitudinal direction of a camshaft on a receiving portion of a cylinder head. There is formed a raceway groove for a ball on the outer peripheral surface of the shaft portion of the camshaft, and the bearing portion of the cylinder head and a mounting member for holding the camshaft with respect to the bearing portion are divided into two parts. An outer ring is attached, and a ball rotatably held by a two-divided retainer is interposed between the pair of half races of the outer race and the raceway groove of the camshaft. Engine camshaft support bearing device.