JP3018871B2 - Timing plate mounting structure for internal combustion engine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a timing plate mounting structure for an internal combustion engine, and more particularly, to a timing plate having a portion to be detected for detecting a crank angle position formed on a peripheral portion thereof, which is simple to a crankshaft. The present invention relates to a technique for mounting at a predetermined relative angle by a structure.

[0002]

2. Description of the Related Art Conventionally, a crank pulley is mounted on a crankshaft by a mounting structure as disclosed in Japanese Utility Model Laid-Open Publication No. 62-185969. The crank pulley disclosed in Japanese Utility Model Laid-Open Publication No. Sho 62-185969 has a key provided on the crankshaft and a key groove formed on the crank pulley fitted to each other so that the crank pulley is rotated in the rotational direction relative to the crankshaft. Is positioned and fixed.

[0003]

By the way, in an internal combustion engine for controlling the ignition timing and the fuel injection timing, information on the crank angle position is required. In this case, a projection is provided at every predetermined angular position on the periphery. By mounting the timing plate at a predetermined relative angle to the crankshaft, and detecting the protrusion with a magnetic pickup or the like,
A crank angle sensor configured to obtain a detection signal at each predetermined crank angle position may be used.

Here, as a structure for positioning and attaching the timing plate to the crankshaft in the rotational direction, conventionally, a method of bolting the timing plate to the crank pulley or a method of standing upright on the end face of the crank pulley is used. A method of positioning the timing plate by fitting the timing plate to a pin (dwell pin) or a method of providing a key for the timing plate on the crankshaft and positioning the key by fitting into a key groove provided on the timing plate have been adopted. .

However, in the conventional timing plate mounting structure, it is desired to provide a structure in which the number of parts and the number of processing steps are relatively large, and the timing plate can be positioned and mounted in a rotational direction with a simpler structure.
SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has as its object to provide a structure in which a timing plate can be positioned and attached to a crankshaft in a rotational direction by a simple structure.

[0006]

SUMMARY OF THE INVENTION Accordingly, the present invention is to position a crank pulley in a rotational direction with respect to the crankshaft by fitting a key provided on the crankshaft with a key groove formed in the crank pulley. An internal combustion engine having a configuration in which a detected portion for detecting a crank angle position is formed on a peripheral portion of the internal combustion engine at a predetermined relative angle with respect to the crankshaft; A claw portion projecting in the axial direction of the crankshaft is formed, and the claw portion is inserted into a key groove of the crank pulley to perform positioning in the rotation direction, and between the crank pulley and the flange portion of the crankshaft. The timing plate was sandwiched and fixed.

[0007]

According to this structure, the key groove of the crank pulley is fitted to the key formed at a predetermined angular position of the crankshaft, and the crank pulley is positioned and attached to the crankshaft in the rotational direction. Therefore, the key groove of the crank pulley is located at a predetermined relative angle with respect to the crankshaft.

Therefore, a claw portion to be inserted into the key groove of the crank pulley is formed on the timing plate, and the claw portion is inserted into the key groove of the crank pulley, so that the timing plate can be moved relative to the crank pulley in a predetermined relative position. The timing plate was mounted at a predetermined relative angle to the crankshaft.

Further, the timing plate is sandwiched and fixed between the crank pulley into which the claw portion is inserted and the flange portion of the crankshaft, and is attached to the crankshaft integrally with the crank pulley.

[0010]

Embodiments of the present invention will be described below. FIG. 1 is a sectional view showing a mounting state of a timing plate and a crank pulley to a crankshaft according to the embodiment, and FIGS. 2A and 2B show a timing plate according to the embodiment.

In FIG. 1, a crankshaft 1 has an end portion tapered through a flange portion 2, and a female screw 3 is formed along an axial direction on an inner peripheral wall of a hollow portion opened to the end surface. Have been. A first crank pulley 4 for a timing belt and a second crank pulley 5 for driving various accessories such as a compressor for an air conditioner, a power steering pump, and an alternator are inserted through the end of the crankshaft 1 in this order, and the female screw 3, the first and second bolts (not shown) are tightened.
The crank pulleys 4 and 5 are pressed against the flange portion 2 to be fixed in the axial direction.

The rotation of the crank pulleys 4, 5 is stopped by fitting the keys 6, 7 formed on the peripheral wall of the crankshaft 1 with the key grooves formed on the crank pulleys 4, 5. Key 6,
The position of the first and second crank pulleys 4 and 5 with respect to the crankshaft 1 is determined in the rotational direction by the position of the key groove 7 and the key groove.

Further, in this embodiment, prior to the insertion of the first crank pulley 4 into the crankshaft 1,
The timing plate 8 is inserted through the crankshaft 1. As shown in FIGS. 2A and 2B, the timing plate 8 has a pair of protrusions 8a and 8b (detected portions) for detecting a crank angle position formed on the periphery thereof so as to face the center of the rotation axis. The timing plate 8 is fixed such that the projections 8a and 8b have a predetermined relative angle with respect to the crankshaft 1.
The angular position of the crankshaft 1 can be detected by detecting a and 8b by detecting means such as a magnetic pickup disposed at a predetermined angular position.

At the opening edge of the mounting hole 9 of the timing plate 8 which is inserted into the crankshaft 1, a claw is formed at a predetermined angle relative to the projections 8a and 8b.
10 are formed. The claw portion 10 is formed so as to project in the axial direction of the crankshaft 1 so as to be inserted into the key groove 4a of the first crank pulley 4 in a state of being attached to the crankshaft 1.

Further, a notch 11 for passing the keys 6 and 7 for the first and second crank pulleys 4 and 5 is provided at the opening edge of the mounting hole 9. Then, the first and second crank pulleys 4 and 5 with respect to the crankshaft 1
When mounting the timing plate 8, first, the notch 11 is connected to the timing plate 8 with the keys 6, 7.
Is inserted through the shaft while being aligned with the position (2), and is inserted at the abutting position of the flange portion 2.

As described above, the notch 11 is provided with the key 6,
7 to pass through, so the claw 10
It is not necessary to dispose it at the position opposite to. Next, the first crank pulley 4 is inserted to a position where it comes into contact with the timing plate 8 while the key grooves 4 a are inserted into the keys 6 and 7. At this time, the first crank pulley 4 is positioned in the rotational direction by fitting the key groove 4a and the key 6, but at the same time, the first crank pulley 4 is rotated around the axis to thereby rotate the first crank pulley 4. The claw 10 of the timing plate 8 is inserted into the key groove 4 a of the pulley 4, and the claw 10 is inserted into the key groove 4 a with respect to the first crank pulley 4 positioned in the rotation direction by the key 6. As a result, the timing plate 8 is positioned in the rotation direction.

Further, the second crank pulley 5 is inserted into the crankshaft 1 while being positioned in the rotation direction by fitting the key 7 and a key groove (not shown). Then, the second crank pulley 5, the first crank pulley 4, and the timing plate 8 are pressed against the flange 2 by tightening bolts that engage with the peripheral end surfaces of the mounting holes 5 a of the second crank pulley 5, and the keys 6, 7 are pressed. The first and second crank pulleys 4 and 5, which are positioned in the rotation direction by fitting with the
The timing plate 8 positioned in the rotation direction by inserting the claw portion 10 into a is fixed in the axial direction.

According to such a configuration, direct positioning in the rotation direction is not performed between the timing plate 8 and the crankshaft 1, but a predetermined position with respect to the crankshaft 1 is established by fitting the key 6 and the key groove 4 a. Since the timing plate 8 is engaged with the first crank pulley 4 attached at a relative angle at a predetermined relative angle to determine the rotational direction, the projections 8a and 8b of the timing plate 8 are connected to the crankshaft 1. It can be positioned at a predetermined relative angle position.

In addition, since the above-described positioning in the rotational direction is performed using the key groove 4a of the first crank pulley 4, only the claw portion 10 inserted into the key groove 4 is formed on the timing plate 8. In addition, the positioning in the rotation direction can be easily performed without significantly increasing the number of parts and the number of processing steps. Furthermore, since the timing plate 8 is sandwiched and fixed between the first crank pulley 4 and the flange portion 2 of the crankshaft 1, a dedicated assembling operation for fixing the timing plate 8 is not required. is there.

In the above embodiment, the first and second crank pulleys 4 and 5 have been described as being mounted on the crankshaft 1. However, even if only one crank pulley is mounted, the timing plate can be similarly mounted. Obviously, 8 can be attached.

[0021]

As described above, according to the present invention,
Attachment for positioning and fixing the timing plate, at which the detected portion for detecting the crank angle position is formed on the peripheral portion, at a predetermined relative angle with respect to the crankshaft,
There is an effect that the operation can be easily performed without increasing the number of parts and the number of processing steps and without increasing the number of steps of the assembly operation.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing a mounting state of a timing plate and a crank pulley in an embodiment.

FIG. 2 is a diagram showing a timing plate in the embodiment, (A) is a front view, and (B) is a cross-sectional view along AA.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Crankshaft 2 Flange part 4 1st crank pulley 4a Keyway 5 2nd crank pulley 6, 7 key 8 Timing plate 8a, 8b Projection part (detection part) 10 Claw part

Claims (1)

(57) [Claims] In an internal combustion engine, a key provided on a crankshaft and a keyway formed on a crank pulley are fitted to each other to position the crank pulley in a rotational direction with respect to the crankshaft. A structure in which a timing plate on which a detected portion for detecting a crank angle position is formed is attached at a predetermined relative angle to the crankshaft, wherein the timing plate has a claw projecting in a crankshaft axial direction, The claw portion is inserted into a key groove of the crank pulley to perform rotational positioning, and the timing plate is sandwiched and fixed between the crank pulley and a flange portion of the crankshaft. Engine timing plate mounting structure.