JP4528211B2 - Ignition system for air-cooled engine - Google Patents

Description

  The present invention relates to an ignition device for an air-cooled engine, which is a type of ignition device in which a plug cap having an ignition part is attached to an ignition plug, and can prevent the ignition plug and the plug cap from falling over.

As an ignition device for an engine, a plug cap provided with an ignition part and this ignition part directly attached to an ignition plug has been put into practical use.
A practical engine ignition device was practically sufficient if the ignition plug and the plug cap were appropriately prevented from falling.

As such an ignition device for an engine, a cylinder head cover that covers a cylinder head of the engine is provided, and a plug cap can be supported around the cylinder head cover (see, for example, Patent Document 1).
JP 2000-161138 A (page 8, FIG. 4)

  FIG. 10 is a diagram for explaining a conventional basic configuration. In an engine ignition device 200, an ignition unit (high pressure generation unit) 201 is connected to a coil unit 202 that generates high pressure and a spark plug (not shown) side. And an adapter part 204. The cylinder head cover 205 is provided with a wiring board 206 that electrically connects the ignition part 201 and a support part 207 that mechanically supports the ignition part 201, and a plug hole of the spark plug. The adapter part 204 is inserted into (not shown), and the adapter part 204 is connected to a spark plug attached to the back of the plug hole.

  The engine ignition device 200 has a structure premised on a water-cooled engine. In general, a water-cooled engine forms a jacket for passing cooling water through a cylinder head or a cylinder block, and the engine is cooled with cooling water. The plug wheel can be formed in this way, and the spark plug can be inserted deep into the cylinder head from this plug wheel, so even if the ignition part is attached to the spark plug, the plug wheel prevents the spark plug from falling Can do.

  However, since the air-cooled engine ignition device is a system that cools the engine with air, it is impossible to form a deep plug hole in the cylinder head. Especially when attaching a heavy ignition part to the ignition plug, It is necessary to attach the plug and the ignison part firmly to prevent the spark plug from falling.

  That is, in an ignition device for an air-cooled engine, when an ignition portion having a heavy weight is attached to the ignition plug, an ignition device capable of firmly attaching the ignition plug and the ignition portion is desired.

  The present invention provides an ignition device for an air-cooled engine that solves the problem that the ignition plug falls when the ignition portion is attached to the ignition plug in the ignition device for an air-cooled engine, and can firmly attach the ignition plug and the ignition portion. This is the issue.

According to a first aspect of the present invention, there is provided an ignition device for an air-cooled engine in which an ignition plug is attached to a combustion chamber of an air-cooled engine, and a plug cap having an ignition portion is attached to the ignition plug. A support surface for supporting the plug cap is provided, and a locking member for locking the plug cap is attached to the support surface. The plug cap is provided with a hook portion for locking to the locking member, and the hook portion is fixed to the fixing member. And the hook is provided to be slidable in the insertion direction of the plug cap .

  For example, in an air-cooled engine, the engine is cooled by air, so a deep plug hole cannot be formed in the combustion chamber. Especially when a heavy ignition part is attached to the spark plug, the spark plug collapses. Therefore, it is desirable to firmly attach the spark plug and the plug cap (ignition part).

Therefore, a support surface for supporting the plug cap is provided on the outer surface of the wall of the valve operating chamber of the engine, and a locking member for locking the plug cap is attached to the support surface, and the plug cap is engaged with the locking member. The spark plug and the ignition part can be firmly supported by providing the hook part to be stopped and locking the hook part to the locking member with the fixing member.
By providing the flange portion so as to be slidable in the insertion direction of the plug cap, it is possible to absorb variations in the height direction of the spark plug.

In the invention according to claim 2, when the locking member is a stud bolt standing on the support surface and the fixing member is a nut, the flange portion is fitted to the stud bolt and the plug cap is allowed to rotate. An arc hole or a long hole is formed.
When the stud bolt standing on the support surface and the fixing member are nuts, an arc hole or a long hole that allows the plug bolt to be fitted and allows the plug cap to rotate is formed in the flange. The plug cap can be rotated (twisted) relative to the spark plug when the plug cap is attached or removed.

The invention according to claim 3 is characterized in that when the locking member is a stud bolt standing on the support surface, the locking member has a step portion substantially the same as the height of the flange portion.
When the stud bolt stands on the support surface, it is possible to avoid excessive tightening of the hook portion on the locking member by providing the locking member with a step portion substantially the same as the height of the hook portion. it can.

In the invention according to claim 1, a support surface for supporting the plug cap is provided on the outer surface of the wall of the valve operating chamber of the engine, and a locking member for locking the plug cap is attached to the support surface. Since the hook part locked to the locking member is provided and the hook part is locked to the locking member by the fixing member, the spark plug and the ignition part can be firmly supported. As a result, there is an advantage that the spark plug can be prevented from falling down and resonance of the spark plug and the plug cap can be prevented.
By providing the flange portion so as to be slidable in the insertion direction of the plug cap, it is possible to absorb variations in the height direction of the spark plug.

  The invention according to claim 2 is a stud bolt standing on the support surface, and when the fixing member is a nut, an arc hole or a long hole that fits the stud bolt and allows the plug cap to rotate when the fixing member is a nut. When the plug cap is attached to or removed from the spark plug, the plug cap can be rotated (twisted) with respect to the spark plug. As a result, the plug cap can be easily attached or removed. That is, there is an advantage that the assembling property of the plug cap can be improved.

  In the invention according to claim 3, when the stud bolt stands on the support surface, the locking member is provided with a step substantially the same as the height of the flange, so that the flange is excessively tightened on the locking member. Can be avoided. As a result, there is an advantage that the assembling property of the plug cap can be improved.

The best mode for carrying out the present invention will be described below with reference to the accompanying drawings. The drawings are viewed in the direction of the reference numerals.
FIG. 1 is a front view of an air-cooled engine employing an ignition device according to a first embodiment of the present invention. An engine (general-purpose engine) 10 as an internal combustion engine includes a crankcase 13 for storing oil (lubricating oil) 12 and A crankshaft 14 as an output shaft mounted horizontally and rotatably on the crankcase 13, a single cylinder block 15 formed integrally and inclined on the crankcase 13, and a cylinder of the cylinder block 15 16 slidably attached to the piston 16, a connecting rod 18 connecting the piston 17 and the crankshaft 14, a cylinder head 21 attached to the opening 19 of the cylinder block 15, and an intake port 22 of the cylinder head 21. An intake valve 24 attached freely and an ascending valve attached to the exhaust port 23 of the cylinder head 21 And freely the exhaust valves 25, a single cylinder and inclined-cylinder OHC (overhead camshaft) type air-cooled engine to the main structure.

  Reference numeral 26 denotes a ground plane (horizontal plane), and the cylinder block 15 is inclined with respect to the ground plane (horizontal plane).

  The engine body 27 includes a crankcase 13, a cylinder block 15, a cylinder head 21, a crankshaft 14, a connecting rod 18, a piston 17, an intake valve 24, and an exhaust valve 25. The crankcase 13, the cylinder block 15, and the cylinder head. 21 constitutes a casing 28 of the engine body 27, and the cylinder block 15 and the cylinder head 21 constitute a combustion chamber 29.

The crankshaft 14 is also a shaft for taking out power, and a power take-out portion 31 is formed at one end, and the power take-out portion 31 is sometimes called PTO (power take-off).
The cylinder head 21 includes a valve operating chamber 32 for driving the intake valve 24 and the exhaust valve 25 by the rotation of the crankshaft 14. In the figure, 33 is an oil level gauge, 41 is a muffler cover, and 45 is a discharge pipe that is an outlet of exhaust gas attached to the muffler cover 41.

  FIG. 2 is a side view of the air-cooled engine employing the ignition device according to the first embodiment of the present invention. The engine 10 includes auxiliary equipment as accessories for operating the engine 10 in the engine body 27, The main components are an air cleaner 35 that draws in outside air, a carburetor 36 that vaporizes fuel (gasoline) and sends it to the combustion chamber 29 (see FIG. 1), a fuel tank 37 that stores fuel, and an exhaust sound of exhaust gas. A muffler 40 (see FIG. 1) for reducing, a recoil starter 39 for starting the engine 10, an oil level detection device (oil alert) 50 for detecting an oil level (lubricating oil level), and an ignition unit 89 for ignition And a plug cap 60 (see FIG. 5).

  In the figure, 42 is an oil supply port for supplying oil, 43 is an exhaust pipe having one end extending from the cylinder head 21 and having a muffler 40 attached to the other end, and 44 is a starting knob (grip) of the recoil starter 39.

  FIG. 3 is a rear view of the air-cooled engine employing the ignition device according to the first embodiment of the present invention. The engine 10 has a generator (not connected) on the opposite side of the power take-out portion 31 (see FIG. 1) of the crankshaft 14. The cooling fan 47 is attached in this order from the inside, the cooling fan 47 is surrounded by a fan cover 48, and a recoil starter 39 is provided that meshes with the crankshaft 14 (see FIG. 1) and rotates at the start. Is covered with a recoil starter cover 49, a main panel 52 is disposed on the lateral upper side of the recoil starter cover 49, and the cover panel 53 covers the interior between the fuel tank 37 and the recoil starter cover 49 while continuing to the main panel 52. Is provided.

  The main panel 52 and the cover panel 53 constitute an operation panel. The main panel 52 includes a switch knob 54 as an operation member for setting the engine 10 to an ON state, and a governor motor (see FIG. 2) provided in the carburetor 36 (see FIG. 2). And an adjustment knob 55 as an operation member for adjusting the characteristic (not shown).

  FIG. 4 is a perspective view of the air-cooled engine ignition device according to the first embodiment of the present invention. The air-cooled engine ignition device 80 includes an ignition plug 82 attached to the wall portion 81 of the valve operating chamber 32 shown in FIG. The plug cap 60 that covers (connects) the spark plug 82, the support surface 84 provided on the outer surface of the wall portion 81 of the valve operating chamber 32 (see FIG. 1), and the locking member provided on the support surface 84 And a nut 86 as a fixing member fitted to the stud bolt 85.

The plug cap 60 is fixed to the stud bolt 85 by being provided in the cap body 88 made of resin, an ignition part (ignition coil) 89 that ignites the spark plug 82 by being built in the cap body 88, and the cap body 88. The ignition unit 89 includes an ignition cable 92 that supplies electric power.
In addition, the collar part 91 is provided with the insertion hole 93 inserted in the stud bolt 85, as shown in FIG. The ignition unit 89 is a part that generates a high voltage.

FIG. 5 is a cross-sectional view taken along line 5-5 of FIG.
In general, an air-cooled engine is a system in which engine cooling is performed by air, so that a deep plug hole cannot be formed in the combustion chamber. Especially when a heavy ignition part is attached to the spark plug, the spark plug Therefore, it is necessary to firmly attach the spark plug and the ignison part.

  Therefore, in the ignition device 80 for the air-cooled engine, the ignition plug 82 is attached to the combustion chamber 29 (see FIG. 1) of the air-cooled engine 10 (hereinafter, the engine 10 is referred to as “air-cooled engine 10”). In an ignition device for an air-cooled engine having a plug cap having a support, a support surface 84 for supporting the plug cap 60 is provided on the outer surface of the wall portion 81 of the valve operating chamber 32 (see FIG. 1) of the engine 10. A stud bolt (locking member) 85 for locking the plug cap 60 is attached, and the plug cap 60 is provided with a flange portion 91 locked to the stud bolt 85, and this flange portion 91 is secured by a nut (fixing member) 86. Locked to the stud bolt 85.

6 (a) and 6 (b) are operation explanatory views of the ignition device for the air-cooled engine according to the first embodiment of the present invention.
In (a), the air-cooled engine ignition device 80 before attachment is shown on the outer support surface 84 of the wall portion 81, and the plug cap 60 is inserted into the ignition plug 82 as indicated by the arrow e1, and the insertion hole 93 of the flange portion 91 is inserted. Is inserted into the stud bolt 85 as shown by the arrow e2, and the nut 86 is screwed into the stud bolt 85, and the flange portion 91 of the plug cap 60 is supported on the support surface 84 on the outer surface of the wall portion 81.

  That is, in (b), a support surface 84 that supports the plug cap 60 is provided on the outer surface of the wall portion 81 of the valve operating chamber 32 (see FIG. 1) of the engine 10, and the plug cap 60 is locked to the support surface 84. A stud bolt (locking member) 85 is attached, and the plug cap 60 is provided with a flange 91 that locks to the stud bolt 85, and the flange 91 is locked to the stud bolt 85 by a nut (fixing member) 86. Thus, the spark plug 82 and the ignition part 89 can be firmly supported. As a result, the spark plug 82 can be prevented from falling down, and resonance of the spark plug 82 and the plug cap 60 can be prevented.

FIG. 7 is a perspective view of an air-cooled engine ignition device according to a second embodiment of the present invention. The same components as those of the air-cooled engine ignition device 80 (see FIG. 5) are denoted by the same reference numerals, and detailed description thereof is omitted.
In the figure, 82 is a spark plug, 84 is a support surface, 85 is a stud bolt, 86 is a nut, 100 is a plug cap, and the plug cap 100 is built into the resin cap body 108 and the cap body 108. The ignition portion 109 for igniting the ignition plug 82, the flange portion 111 fixed to the stud bolt 85 by being provided on the cap body 108, and the ignition cable 112 for supplying electric power to the ignition portion 109, and the flange portion 111 Further, a circular arc hole having a locus centering on the axis C of the spark plug 82 is formed.

  That is, in the air-cooled engine ignition device 110, when the locking member is the stud bolt 85 standing on the support surface 84 and the fixing member is the nut 86, the flange 111 is fitted to the stud bolt 85. It can be said that the arc hole 113 that allows the plug cap 100 to rotate is formed.

  When the locking member is the stud bolt 85 standing on the support surface 84 and the fixing member is the nut 86, the arc hole that allows the flange 111 to fit the stud bolt 85 and allow the plug cap 100 to rotate. By forming 113, the plug cap 100 can be rotated (twisted) with respect to the spark plug 82 as shown by an arrow e3 when the plug cap 100 is attached to or removed from the spark plug 82. As a result, the plug cap 100 can be easily attached or removed. That is, the assembling property of the plug cap 100 can be improved.

FIG. 8 is a perspective view of an air-cooled engine ignition device according to a third embodiment of the present invention. The same components as those of the air-cooled engine ignition device 80 (see FIG. 5) are denoted by the same reference numerals, and detailed description thereof is omitted.
In the figure, 60 is a plug cap, 81 is a wall portion, 82 is a spark plug, 84 is a support surface, 86 is a nut, 88 is a cap body, 89 is an ignition portion, 91 is a collar portion, 92 is an ignition cable, and 93 is The ignition device 120 of the air-cooled engine, which is an insertion hole, has a stud bolt 125 as a locking member provided with a stepped portion 126 having substantially the same height as the flange portion 91.

  In the air-cooled engine ignition device, when the locking member is the stud bolt 125 standing on the support surface 84, it can be said that the stud bolt 125 is provided with a step 126 that is substantially the same as the height of the flange 91.

  When the stud bolt 125 is erected on the support surface 84, the stud bolt 125 is provided with the step 126 substantially the same as the height of the flange 91, so that the stud 91 is excessively attached to the stud bolt (locking member) 125. Tightening can be avoided. As a result, the assembling property of the plug cap 60 can be improved.

FIG. 9 is a perspective view of an air-cooled engine ignition device according to a third embodiment of the present invention. The same components as those of the air-cooled engine ignition device 80 (see FIG. 5) are denoted by the same reference numerals, and detailed description thereof is omitted.
In the figure, 81 is a wall portion, 82 is a spark plug, 84 is a support surface, 85 is a stud bolt, 86 is a nut, 130 is a plug cap, and the plug cap 130 is made of a resin cap body 138 and the cap body. The ignition part 139 that ignites the spark plug 82 by being built in 138, the flange part 141 that is fixed to the stud bolt 85 by being provided in the cap body 138 so as to be slidable in the insertion direction of the spark plug 82, and the ignition part 139 An ignition cable 142 for supplying electric power.

  The flange portion 141 includes an insertion hole 143 to be inserted into the stud bolt 85 and a convex portion 144 slidably formed on the cap body 138. Moreover, the cap main body 138 is provided with the recessed part 145 which guides the convex part 144 of the collar part 141 so that a slide is possible. Note that it is preferable that the convex portion 144 is set to have a dimensional relationship that allows the concave portion 145 to be tightly fitted in order to prevent the spark plug 82 from falling down and to prevent resonance of the spark plug 82 and the plug cap 130.

It can be said that the ignition device 140 of the air-cooled engine is provided with the flange 141 so as to be slidable in the insertion direction of the plug cap 130.
By providing the flange 141 so as to be slidable in the insertion direction of the plug cap 130, it is possible to absorb variations in the dimension of the spark plug 82 in the height direction. As a result, the plug cap 130 can be inserted deeply into the spark plug 82.

  In the air-cooled engine ignition device according to the second embodiment of the present invention, as shown in FIG. 7, a circular arc hole 113 having a locus centering on the axis C of the spark plug 82 is provided in the flange 111. The hole is not limited to this, and may be a hole (for example, a long hole or an oval hole) that allows the plug case to rotate with respect to the stat bolt when the plug case is attached to the spark plug.

  The ignition device for an air-cooled engine according to the present invention is suitable for use in a small air-cooled engine or an automobile engine.

It is a front view of the air-cooled engine which employ | adopted the ignition device of 1st Embodiment which concerns on this invention. 1 is a side view of an air-cooled engine that employs an ignition device according to a first embodiment of the present invention. It is a rear view of the air-cooled engine which employ | adopted the ignition device of 1st Embodiment which concerns on this invention. 1 is a perspective view of an ignition device for an air-cooled engine according to a first embodiment of the present invention. Sectional view along line 5-5 in FIG. It is operation | movement explanatory drawing of the ignition device of the air-cooled engine of 1st Embodiment which concerns on this invention. It is a perspective view of the ignition device of the air-cooled engine of 2nd Embodiment which concerns on this invention. It is a perspective view of the ignition device of the air-cooled engine of 3rd Embodiment which concerns on this invention. It is a perspective view of the ignition device of the air-cooled engine of 3rd Embodiment which concerns on this invention. It is a figure explaining the conventional basic composition.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Engine, 29 ... Combustion chamber, 60, 100, 130 ... Plug cap, 80, 110, 120, 140 ... Air-cooled engine ignition device, 81 ... Wall part, 82 ... Spark plug, 84 ... Support surface, 85, 125 ... locking member (stud bolt), 86 ... fixing member (nut), 91, 111, 141 ... flange, 113 ... arc hole, 126 ... step.

Claims (3)

In an ignition device for an air-cooled engine in which an ignition plug is attached to a combustion chamber of an air-cooled engine and a plug cap having an ignition part is attached to the ignition plug.
A support surface for supporting the plug cap is provided on the outer surface of the wall of the valve operating chamber of the engine, and a locking member for locking the plug cap is attached to the support surface.
The plug cap includes a hook portion that is locked to the locking member, and the hook portion is locked to the locking member by a fixing member .
The igniter for an air-cooled engine, wherein the flange portion is provided so as to be slidable in the insertion direction of the plug cap .   When the locking member is a stud bolt standing on the support surface, and the fixing member is a nut, an arc hole or a length for fitting the flange to the stud bolt and allowing the plug cap to rotate The ignition device for an air-cooled engine according to claim 1, wherein a hole is formed.   2. The ignition device for an air-cooled engine according to claim 1, wherein when the locking member is a stud bolt standing on the support surface, the locking member includes a step portion substantially the same as the height of the flange portion.

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