【図面の簡単な説明】[Brief explanation of the drawing]
第１，２図はこの考案の第１実施例を示し、第
１図は内燃機関に点火時期視認機構を設けた概略
図、第２図は点火時期視認機構を設けたベルトカ
バーとクランクプーリとの一部断面図である。第
３，４図はこの考案の第２実施例を示し、第３図
は点火時期視認機構を設けたベルトカバーとクラ
ンクプーリとの一部断面図、第４図は点火時期視
認機構を設けた正面図である。第５〜１２図は従
来の点火時期視認機構を示すもので、第５図は内
燃機関に点火時期視認機構を設けた概略図、第６
図は点火時期視認機構を設けたベルトカバーとク
ランクプーリとの一部断面図、第７図は内燃機関
に点火時期視認機構を設けた概略図、第８，９図
は点火時期視認機構を設けたベルトカバートとク
ランクプーリとの一部断面図、第１０図は内燃機
関に点火時期視認機構を設けた概略図、第１１図
は点火時期視認機構を設けたベルトカバーとクラ
ンクプーリとの一部断面図、第１２図は点火時期
視認機構の正面図である。
図において、２は内燃機関、４はクランク軸、
６はクランクプーリ、８は補機駆動プーリ、２６
はベルトカバー、２８は点火時期視認機構、３０
は突出部、３２は固定側マーク、３４は移動側マ
ーク、そして３６は延設部である。
Figures 1 and 2 show the first embodiment of this invention. Figure 1 is a schematic diagram of an internal combustion engine equipped with an ignition timing visual confirmation mechanism, and Figure 2 is a diagram showing a belt cover and crank pulley equipped with an ignition timing visual confirmation mechanism. FIG. Figures 3 and 4 show a second embodiment of this invention, Figure 3 is a partial cross-sectional view of a belt cover and crank pulley equipped with an ignition timing visual confirmation mechanism, and Figure 4 is a partial cross-sectional view of a crank pulley equipped with an ignition timing visual confirmation mechanism. It is a front view. Figures 5 to 12 show conventional ignition timing visual confirmation mechanisms, and Figure 5 is a schematic diagram of an internal combustion engine equipped with an ignition timing visual confirmation mechanism.
The figure is a partial sectional view of a belt cover and crank pulley equipped with an ignition timing visual confirmation mechanism, Figure 7 is a schematic diagram of an internal combustion engine equipped with an ignition timing visual confirmation mechanism, and Figures 8 and 9 are equipped with an ignition timing visual confirmation mechanism. Fig. 10 is a schematic diagram of an internal combustion engine equipped with an ignition timing visual confirmation mechanism, and Fig. 11 is a partial cross-sectional view of a belt cover and a crank pulley equipped with an ignition timing visual confirmation mechanism. FIG. 12 is a front view of the ignition timing visual recognition mechanism. In the figure, 2 is an internal combustion engine, 4 is a crankshaft,
6 is a crank pulley, 8 is an auxiliary drive pulley, 26
is the belt cover, 28 is the ignition timing visual confirmation mechanism, 30
32 is a fixed side mark, 34 is a movable side mark, and 36 is an extended portion.