JPH08501Y2 - Engine timing indicator - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a timing indication device for an engine, and more particularly to a technique for improving reading accuracy.

<Prior Art> Conventionally, in an engine, as a timing indicator device including a timing mark indicating top dead center of a piston, ignition timing or opening / closing timing of a valve, and an indicator for reading the mark, it is used on the crank pulley side of the engine. A timing mark is provided, and one pin-shaped indicator extending parallel to the crank pulley shaft is provided on the engine body side, or a linear groove is provided on the engine crank pulley side and the timing is provided on the engine body side. Some have a mark (see Japanese Patent Publication No. 58-53238).

The former timing indicating device is schematically shown in FIG. 5, in which a crank pulley 1 is provided with a timing mark 2 and an engine body 3 side is provided with a pin-shaped indicator 4.

In this case, reading is performed by aligning the line of sight of the indicator 4 from above with the indicator 4 and the timing mark 2.

<Problems to be Solved by the Invention> However, such a conventional timing indication device has the following problems.

That is, a reading error is likely to occur depending on the angle of the line of sight at which the indicator 4 and the timing mark 2 are viewed together.

For example, when the indicator 4 and the timing mark 2 are viewed together from the position of the line of sight A in FIG. 5A, the reading position at that time is a, but when the indicator 4 and the timing mark 2 are viewed from the position of the line of sight B together. The reading position at that time is b, and a reading error c occurs depending on the line-of-sight position.

In addition, the drive load of the accessory may change according to the specification variation due to the option setting of the accessory parts, and it may be necessary to increase or decrease the width of the belt. In this case, the width of the crank pulley 1 in the axial direction also needs to be changed, which causes the following problems.

For example, in FIG. 5 (b), when the axial width of the crank pulley 1 is changed from what is shown by the chain double-dashed line in the figure to what is shown by the solid line, the position of the timing mark 2 formed on the crank pulley 1 is As the indicator 4 moves forward (in the direction of the arrow), the initial length of the indicator 4 causes the timing mark 2 and the tip of the indicator 4 to be far apart from each other, and accurate reading cannot be performed. Therefore, the indicator 4
It is conceivable to extend the shape from the beginning as shown by the dotted line in the figure.
If the width in the axial direction is short, the timing mark 2 is hidden under the indicator 4 and becomes difficult to see.

Therefore, in view of the above conventional problems, the present invention has
In the one that uses the timing mark on the crank pulley side and the pin-shaped indicator on the engine body side,
(EN) Provided is a timing indication device for an engine, which can improve reading accuracy by improving the structure of the indicator side and specify the positional relationship between the timing mark and the indicator and can cope with different specifications of the crank pulley. The purpose is to

<Means for Solving the Problems> Therefore, in the engine timing indicator of the present invention, the timing mark is provided on the front end face of the outer peripheral edge of the crank pulley of the engine, and the crank pulley shaft is provided on the engine body side. Two pin-shaped indicators extending parallel to each other are provided in parallel in the radial direction of the crank pulley at a predetermined interval, and the two parallel pin-shaped indicators project forward from the front end face of the crank pulley. Of the two indicators, the indicator arranged on the outer side in the radial direction of the crank pulley is projected longer than the indicator arranged on the inner side, and the straight line extending between the tips of the both indicators is aligned with the timing mark. A configuration in which the tip portions of both indicators are formed to have a smaller diameter than the other That.

<Operation> In such a configuration, when the indicator and the timing mark are viewed together, the angle of the line of sight is such that the two indicators overlap and the straight line extending between the tips of the two indicators and the timing mark coincide with each other. By taking it, the angle at which the indicator and the timing mark are viewed together is always correct, that is, the reading position of the timing mark is specified in the circumferential direction and radial direction of the crank pulley, so there is a reading error. Is less likely to occur.

Also, when the drive load of the auxiliary machine changes according to the specification variation due to the optional setting of auxiliary machine parts, the width of the belt is increased or decreased, and the axial width of the crank pulley also needs to be changed, It can be dealt with as follows.

That is, by extending the indicator long and aligning it with a crank pulley having a long axial width, it is possible to accurately see the timing mark and the indicator on crank pulleys of various lengths, and to make the tip of the indicator smaller in diameter. Since it is formed as described above, it is possible to accurately see the timing mark and the indicator without the timing mark being hidden by the indicator.

<Embodiment> An embodiment of the present invention will be described below with reference to the drawings.

1 to 3, a crank pulley 6 is fixedly attached to a tip end portion of a crankshaft (not shown) protruding from a timing chain cover 5 of the engine. A plurality of timing marks 7 formed of linear grooves are engraved at predetermined intervals on the front end surface of the outer peripheral edge of the crank pulley 6. In the present embodiment, the linear groove is formed so as to be continuous from the front end surface of the outer peripheral edge portion of the crank pulley 6 to the peripheral surface. On the other hand, on the engine body side, two pin-shaped indicators 8 and 9 extending parallel to the pulley shaft of the crank pulley 6 are arranged in parallel in the radial direction of the crank pulley 6 at a predetermined interval.

That is, at the position above the crank pulley 6 of the timing chain cover 5, two pin-shaped indicators 8 and 9 extending parallel to the crank pulley shaft are provided in parallel vertically on the vertical line at a predetermined interval. There is. In this case, the timing chain cover 5 is integrally formed with a boss 10 projecting forward, and a rear end portion of the indicators 8 and 9 is provided in a hole (not shown) provided at a front end portion of the boss 10. Pressed and fixed.

Each of the indicators 8 and 9 is formed such that a portion having a predetermined length from the tip end has a smaller diameter than other portions (small diameter portions 8a and 9).
a).

Here, two pin-shaped indicators 8 and 9 arranged in parallel
Respectively project forward from the front end face of the crank pulley 6 and project the indicator 8 arranged on the outer side in the radial direction of the crank pulley 6 out of the indicators 8 and 9 longer than the indicator 9 arranged on the inner side. Then, the extension line of the straight line connecting the tips of both indicators 8 and 9 and the timing mark 7 are aligned.

In this case, the positions of the tip surfaces of the indicators 8 and 9 are set to positions beyond the tip surface positions of the small-width crank pulley 6a described later and slightly beyond the tip surface positions of the large-width crank pulley 6b.

The length of the small-diameter portions 8a, 9a of the indicators 8, 9 is such that the base end position of the small-diameter portions 8a, 9a is located rearward beyond the tip end surface position of the narrow crank pulley 6a. Set.

The protruding length of the upper indicator 8 from the tip surface of the boss 10 is set to be slightly longer than that of the lower indicator 9.

For example, the protrusion length of the indicators 8 and 9 from the tip surface of the boss 10 is 50 mm, and the diameter of the small diameter portions 8a and 9a of the portion having a length of 20 mm from the tips of the indicators 8 and 9 is 2 to 3 mm, and other portions. Is formed with a diameter of 5 mm.

In the figure, 13 is a water inlet and 14 is a cooling fan.

 The operation and effect of this configuration will be described.

When viewing the indicators 8 and 9 and the timing mark 7 together, as shown in FIG.
By aligning the indicator 8 and 9 with the timing mark 7 by bringing the indicator 8 and 9 and the timing mark 7 so that the extended line of the straight line connecting the tips of both indicators 8 and 9 coincides with the timing mark 7. Is always appropriate, that is, the reading position of the timing mark 7 is defined in the circumferential direction and the radial direction of the crank pulley 6, so that a reading error is unlikely to occur.

In particular, according to the above configuration, since the timing mark 7 is provided on the front end surface of the outer peripheral edge portion of the crank pulley 6, the timing mark 7 can be accurately read in the radial direction of the crank pulley 6.

Incidentally, when the timing mark is provided on the front end surface inside the outer peripheral portion of the crank pulley 6, the timing mark cannot be accurately read in the radial direction of the crank pulley 6.

Further, according to such a configuration, the drive load of the auxiliary machine changes according to the specification variation due to the optional setting of the auxiliary machine parts, the width of the belt is increased or decreased, and the width of the crank pulley 6 in the axial direction also needs to be changed. If it does occur, it can be dealt with as follows.

For example, when a crank pulley 6a having a small axial width is applied, the line of sight in the direction of arrow X in FIG. 2 reaches the timing mark 7 through the tip positions of the small diameter portions 8a and 9a of the two indicators 8 and 9. .

On the other hand, when the crank pulley 6b having a large width in the axial direction is applied, the line of sight in the direction of the arrow Y in FIG. 2 reaches the timing mark 7 through the tip surfaces of the two indicators 8 and 9.

Therefore, as in the present embodiment, by extending the indicators 8 and 9 to match the crank pulley 6b having a long axial width, the timing marks 7 and the indicators 8 on the crank pulleys 6a and 6b having two kinds of lengths are provided. It is possible to see exactly with 9 and 9.

Moreover, in this case, since the tips of the indicators 8 and 9 are formed to have a small diameter, the crank pulley 6a has a small axial width.
When the above is applied, the timing marks 7 are not greatly obscured by the indicators 8 and 9, and the timing marks 7 and the indicators 8 and 9 can be accurately aligned and viewed.

<Advantages of the Invention> As described above, according to the engine timing indication device of the present invention, the timing mark is provided on the front end face of the outer peripheral edge portion of the crank pulley of the engine, and the crank pulley shaft is provided on the engine body side. And two pin-shaped indicators that extend in parallel with each other are arranged in parallel in the radial direction of the crank pulley at a predetermined interval, and the two parallel pin-shaped indicators project forward from the front end face of the crank pulley. Of the two indicators, the indicator arranged on the outer side in the radial direction of the crank pulley is projected longer than the indicator arranged on the inner side, and the straight line extending between the tips of both indicators is aligned with the timing mark. Since the tip parts of both indicators are formed to have a smaller diameter than the other, Since the reading position of the timing mark can be specified in the circumferential direction and radial direction of the crank pulley,
It is possible to suppress the occurrence of timing mark reading errors, improve the reading accuracy, and even if the timing mark position changes due to different specifications of the crank pulley, the timing mark reading can be executed accurately and reliably. The effect is great.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of an engine timing indicating device according to the present invention, FIG. 2 is a side view of the same embodiment as above, FIG. 3 is a view in the direction of arrow A in FIG. 2, and FIG. FIG. 5A is a front view showing a timing mark reading state according to the embodiment, FIG. 5B is an oblique top view, and FIG. 5A is a front view showing a timing mark reading state by a conventional timing indicator device. The figure and the same figure (b) are the side views. 5: Timing chain cover, 6 (6a, 6b) ... Crank pulley, 7 ... Timing mark, 8, 9 ... Indicator, 8a, 9a ... Small diameter part

Claims (1)

[Scope of utility model registration request] 1. A timing mark is provided on a front end surface of an outer peripheral edge portion of a crank pulley of an engine, and two pin-shaped indicators extending in parallel to the crank pulley shaft are provided on an engine body side in a predetermined direction in the crank pulley radial direction. The two pin-shaped indicators arranged in parallel are spaced apart from each other, and the two parallel pin-shaped indicators project forward of the front end face of the crank pulley. Characterized in that the tip of each of the indicators is formed to have a diameter smaller than that of the other indicators, while the projection extends longer than the indicator placed in the above, and the straight line connecting the tips of the both indicators is aligned with the timing mark. And engine timing indication device.