JPH0442506Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] This invention relates to a crank angle detection device for an outboard motor, and in particular, the crank angle detection section is set to a position where the rotation of the ring gear is lower than the position where the pinion of the starter motor and the ring gear mesh. An outboard motor that can prevent metal powder generated by the meshing of the pinion of a starter motor and a ring gear from being sucked into the crank angle detecting section and having an adverse effect on the crank angle detecting section by providing the outboard motor at a rearward position in the direction. The present invention relates to a crank angle detection device.

[Conventional technology]

Internal combustion engines and outboard motors for vehicles are provided with a flywheel, which is a rotating body that is attached to the end of a crankshaft and reduces rotational fluctuations and torque fluctuations. This flywheel is provided with a ring gear that meshes with the pinion of the starter motor, and when the engine is started, the starter motor is driven to rotate the flywheel, which in turn rotates the crankshaft and starts the engine. Furthermore, a crank angle detection coil serving as a crank angle detection section that detects the crank angle by counting the number of teeth of the ring gear is provided on the outer circumference of the ring gear. This crank angle detection coil has a height restriction because it is compatible with the ring gear, and is generally placed on the axis of the crankshaft where the height is optimum and it is easy to install (indicated by arrow P in Figure 1). It is installed by providing a seat in the cylinder or crankcase (first and second
In the figure, reference numeral 32 is a crank angle detection coil).

Further, an outboard motor having a crank angle detection section is disclosed in, for example, Japanese Utility Model Publication No. 60-37918. The device described in this publication has a presser retainer fixed to the lower surface of the magnetic stator, and an engagement holding surface provided at one end of the presser retainer holds the upper surface of the timer base to restrict axial movement. By doing so, we aim to reduce the number of parts and improve installation work efficiency.

[Problem that the invention attempts to solve]

By the way, when the starter motor is driven, metal powder is generated due to the engagement between the pinion of the starter motor and the ring gear of the flywheel. For this reason, in conventional devices, the crank angle detection coil, which has a magnetic material such as a magnet, is placed at a position where the pinion and ring gear mesh (shown as S position in Figure 1).
Since the pinion and the crank angle detection coil are arranged adjacent to each other in the forward direction of the ring gear (indicated by position P in Fig. 1), that is, in the rotation direction of the ring gear, metal powder is The metal powder flows toward the crank angle detection coil and is attracted by the magnetic material of the crank angle detection coil, which has an adverse effect on the crank angle detection coil, resulting in functional deterioration of the crank angle detection coil and the accurate crank angle detection coil. This resulted in inconveniences such as the inability to detect angles.

In addition, when installing the crank angle detection coil at a position other than on the axis of the crankshaft, in order to make the crank angle detection coil correspond to the ring gear,
A mounting boss having a predetermined height is required on the cylinder portion or crankcase, which is difficult to manufacture, and the mounting condition deteriorates due to vibration, which makes installation difficult.

[Purpose of invention]

Therefore, the purpose of this invention is to eliminate the above-mentioned inconvenience by providing the crank angle detection section at a position rearward in the rotational direction of the ring gear from the position where the pinion of the starter motor and the ring gear mesh.
This prevents metal powder generated by the engagement of the pinion and ring gear from being sucked into the crank angle detection part and having an adverse effect on the crank angle detection part, and allows the crank angle detection part to accurately detect the crank angle. To realize a machine crank angle detection device.

[Means for solving problems]

In order to achieve this object, this invention provides an outboard motor in which a flywheel having a ring gear engaged with the pinion of the starter motor is provided on the crankshaft, and a crank angle detector is provided to detect the crank angle by the rotation of the ring gear. In the crank angle detection device, the crank angle detection section is provided at a position rearward in the rotational direction of the ring gear from a position where the pinion of the starter motor and the ring gear mesh with each other.

[Effect]

According to the configuration of this invention, metal powder is generated when the pinion and ring gear mesh, but since the crank angle detection section is provided at a position rearward in the rotational direction of the ring gear from the position where the pinion and ring gear mesh. This prevents the metal powder from flowing toward the crank angle detection section, thereby preventing the metal powder from being sucked by the crank angle detection section and adversely affecting the crank angle detection section. This makes it possible to accurately detect the crank angle while avoiding functional deterioration of the crank angle detection section, and to appropriately control the ignition timing and the like.

〔Example〕

Embodiments of this invention will be described in detail and specifically below based on the drawings.

1 and 2 show an embodiment of this invention. In the figure, 2 is a cylinder portion constituting an internal combustion engine of an outboard motor, 4 is a crankcase, and 6 is a crankshaft. A flywheel 8 is attached to the end of the crankshaft 6. The flywheel 8 is a rotating body that reduces installation rotational fluctuations, torque fluctuations, and the like. A ring gear 10 is provided on the outer periphery of the flywheel 8. This ring gear 10 includes a pinion 14 of the starter motor 12.
are provided in mesh with each other. The starter motor 12 is attached to the cylinder portion 2 or the crankcase 4 via a mounting bracket 16 with fixtures 18 , 18 .

The mounting bracket 16 is provided with a rear position (first position) in the rotational direction
The crank angle detection coil 2, which is a crank angle detection section, is attached to the coil mounting portion 16a of the
0 is set. That is, the crank angle detection coil 20 and the pinion 14 are sequentially arranged adjacent to each other in the rotational direction X of the ring gear 10. The crank angle detection coil 20 has a magnetic material such as a magnet, detects the crank angle by counting the number of teeth of the ring gear 10 as the ring gear 10 rotates, and uses the detected value of the crank angle as the ignition timing, for example. This is what is output to the control device.

Further, the mounting bracket 1 of the starting motor 12
6 is configured to have an optimal height that allows the crank angle detection coil 20 to correspond to the ring gear 10.

Next, the operation of this embodiment will be explained.

When the starter motor 12 is driven, the ring gear 10 meshing with the pinion 14 rotates, and the rotation of the ring gear 10 rotates the crankshaft 6, thereby starting the internal combustion engine.

By the way, when the pinion 14 and the ring gear 10 mesh with each other, metal powder is generated. However, in this embodiment, the crank angle detection coil 20 is connected to the pinion 14 and the ring gear 1.
0, the metal powder generated by the meshing of the pinion 14 and the ring gear 10 is located on the side opposite to the crank angle detection coil 20 side. The metal powder flows forward in the rotational direction The crank angle can be detected accurately and the ignition timing etc. can be appropriately controlled.

Further, the crank angle detection coil 20 is attached to a coil mounting portion 16a of the mounting bracket 16, which is formed at a position A rearward in the rotational direction X of the ring gear 10 from a position S where the pinion 14 and the ring gear 10 mesh with each other.
Since the starting motor 12 is directly attached to the outer periphery of the ring gear 10, no matter where the starter motor 12 is placed on the outer periphery of the ring gear 10, the crank angle detection coil 20 is located in the direction of rotation of the ring gear 10 from the position S where the pinion 14 and the ring gear 10 mesh. Since it is located behind X, the degree of freedom in mounting the starter motor 12 is increased, which is advantageous in practice.

Furthermore, since the crank angle detection coil 20 is attached to the coil attachment portion 16a of the mounting bracket 16, which has an optimal height corresponding to the ring gear 10, a special attachment boss or the like is required to attach the crank angle detection coil 20. There is no need to provide a separate coil attachment tool, which reduces the number of parts, facilitates the installation work, and makes it inexpensive.

[Effect of idea]

As is clear from the above detailed explanation, according to this invention, by providing the crank angle detection section at a position rearward in the rotational direction of the ring gear than the position where the pinion of the starter motor and the ring gear mesh, the meshing between the pinion and the ring gear is improved. Since the metal powder generated by the crank angle detection part does not have an adverse effect on the crank angle detection part, functional deterioration of the crank angle detection part can be prevented.

Furthermore, if the crank angle detection section is installed using the starting motor's mounting bracket, it can be installed at an appropriate height that corresponds to the ring gear, and there is no need to provide a separate coil mount for the crank angle detection section. , the number of parts can be reduced, the installation work can be made easier, and the cost can be reduced.

[Brief explanation of drawings]

1 and 2 show an embodiment of this invention, with FIG. 1 being a partial plan view of the outboard motor, and FIG. 2 being a partial side view of the outboard motor. In the figure, 2 is a cylinder part, 4 is a crankcase, 6 is a crankshaft, 8 is a flywheel, 1
0 is a ring gear, 12 is a starter motor, 14 is a pinion, 16 is a mounting bracket, 16a is a coil mounting portion, and 20 is a crank angle detection coil.

Claims (1)

[Claims for Utility Model Registration] 1. Crank angle of an outboard motor in which a flywheel having a ring gear that engages with a pinion of a starter motor is provided on the crankshaft, and a crank angle detection section that detects the crank angle by rotation of the ring gear is provided. A crank angle detecting device for an outboard motor, characterized in that the crank angle detecting section is provided at a position rearward in the rotational direction of the ring gear from a position where the pinion of the starter motor and the ring gear mesh with each other. 2. The crank angle detecting device for an outboard motor according to claim 1, wherein the crank angle detecting section is a crank angle detecting section attached to a mounting bracket of the starting motor.