JPH08312512A - Detection device of ignition timing, etc., in internal combustion engine - Google Patents

Abstract

PURPOSE: To certainly seal a point to pass through by installing one end of a grommet fit in a drawing part of a position sensor on an inner peripheral edge of a through hole of a timing cover case on its outer peripheral part and providing a ring projected part making contact with an outer peripheral surface of the drawing part of the position sensor on an inner periphery of the other end. CONSTITUTION: An electric wiring drawing part 10a of a position sensor 10 is constituted in a recessed part 9a of a part of the position sensor 10 provided in a timing cover case 9 so as to project from a through hole 9b drilled on the timing cover case 9. Additionally, a grommet 12 cylindrically formed of such a soft elastic body as rubber, etc., to fit on the drawing part 10a of the position sensor 10 is installed on the timing cover case 9 by fitting an inner peripheral edge of the through hole 9b in a ring groove of an outer peripheral surface of a boss part 12a integrally formed provided on an outer periphery of its one end. Furthermore, a ring projected part 12c making contact with an outer peripheral surface of the drawing part 10a of the position sensor 10 is integrally provided on an inner peripheral surface of the other end.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for detecting the timing of ignition timing with respect to the movement of a piston, the number of revolutions or the like in an internal combustion engine.

[0002]

2. Description of the Related Art In a recent internal combustion engine, in order to transmit the rotation of a crankshaft to a camshaft, a timing pulley fitted to the camshaft, an outer peripheral surface of a rotation transmitting wheel such as a timing sprocket, or the like. , The outer peripheral surface of the disc attached to the rotation transmitting wheel is provided with a notch or a protrusion showing the phase of each cylinder, while the notch or the protrusion is provided close to the outer periphery of the rotation transmitting wheel or the disc. By providing a position sensor for detecting the position, the ignition timing, the rotation speed, or the like is detected by this position sensor as an electric signal.

By the way, since a rotation transmission wheel such as a timing pulley or a timing sprocket on the camshaft is constructed so as to be covered by a timing cover case, a portion near the rotation transmission wheel is provided. When mounting the position sensor, the lead-out portion of the electric wiring in the position sensor must penetrate the timing cover case and project to the outside.

[0004]

However, the position sensor and the timing cover case are separately attached to the internal combustion engine, and the position sensor attached to the internal combustion engine and the position on the timing cover case are attached to the internal combustion engine. Since there is a relatively large dimensional error in the relative positional relationship between the sensor and the through hole formed to penetrate the lead-out portion of the sensor, the lead-out portion of the position sensor and the timing cover case are punched. There is a problem that it is not possible to seal the space between the provided through holes with sufficient airtightness.

The present invention has a technical problem to solve this problem.

[0006]

In order to achieve this technical object, the present invention provides an "internal combustion engine having a camshaft on its upper surface,
Timing for detecting a position sensor for detecting a power transmission wheel fitted to the camshaft or a notch or a protrusion provided on a disc attached to the power transmission wheel, and a timing at which a lead-out portion of an electric wire in the position sensor covers the power transmission wheel. In a detection device mounted so as to project from a through hole formed in a cover case, a grommet formed in a tubular shape with a soft elastic body such as rubber is fitted to the drawer portion of the position sensor, and the grommet One end is attached to the inner peripheral edge of the through hole formed in the timing cover case at the outer peripheral portion thereof, while the other end of the grommet has an annular protrusion that comes into contact with the outer peripheral surface of the drawer portion of the position sensor. The unit is integrally provided. "."

[0007]

[Operation] With this configuration, a relatively large space is provided between the position sensor attached to the internal combustion engine and the through hole formed in the timing cover case for penetrating the drawer portion of the position sensor. When there is a dimensional error in the relative positional relationship, the grommet made of soft elastic body has one end attached to the inner peripheral edge of the through hole in the timing cover case, and the annular protrusion at the other end is the drawer portion in the position sensor. Will be elastically deformed in contact with the outer peripheral surface of the.

[0008]

Therefore, according to the present invention, a relatively large relative position is provided between the position sensor attached to the internal combustion engine and the through hole formed in the timing cover case for penetrating the drawer portion of the position sensor. Even if there is a dimensional error in the positional relationship, it is possible to reliably seal the position where the lead-out portion of the position sensor penetrates the timing cover case.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of the present invention will be described below with reference to the drawings of FIGS. In the figure, reference numeral 1 denotes an internal combustion engine in which a cylinder head 3 is fastened to the upper surface of a cylinder block 2 and a cylinder head cover 4 is fastened to the upper surface of the cylinder head 3, and is axially supported on the upper surface of the cylinder head 3. A timing pulley 6 is fitted to a portion where one end of the cam shaft 5 projects from the side surface of the internal combustion engine 1, and a timing belt 7 from a crank shaft (not shown) in the internal combustion engine 1 is fitted to the timing pulley 6. It is wrapped around.

On the inner surface of the timing pulley 6, there is mounted a disk 8 having a plurality of cutouts 8a on the outer periphery thereof for indicating the phase of each cylinder so as to rotate together with the timing pulley 6. There is. Furthermore, the timing pulley 6 and the timing belt 7 are provided on the side surface of the internal combustion engine 1.
A timing cover case 9 for covering the whole of the above is detachably attached by a plurality of bolts (not shown).

Reference numeral 10 senses each notch 8a on the outer circumference of the disc 8 at a position substantially right below the timing pulley 6 and sandwiched by the timing belt 7 wound around the timing pulley 6. The position sensor provided for this purpose is shown.
Is detachably attached to the bolt 11 with respect to the cylinder head 3.

A recess 9a is provided in a portion of the timing cover case 9 corresponding to the position sensor 10, and an electric wiring lead-out portion 10a of the position sensor 10 is provided in the recess 9a. It is configured so as to penetrate through and project from the through hole 9 b formed in 9. Further, a grommet 12 formed in a cylindrical shape by a soft elastic body such as rubber is fitted on the pull-out portion 10a of the position sensor 10, and one end of the cylindrical grommet 12 is integrally formed on the outer periphery of a boss. By fitting the inner peripheral edge of the through hole 9b into the annular groove 12b engraved on the outer peripheral surface of the portion 12a, the inner peripheral surface at the other end of the tubular grommet 12 is attached to the timing cover case 9. An annular protrusion 12c that comes into contact with the outer peripheral surface of the drawer 10a of the position sensor 10 is integrally provided.

In this structure, one end of the grommet 12 is attached to the timing cover case 9 by fitting the inner peripheral edge of the through hole 9b in the timing cover case 9 into the annular groove 12b of the boss portion 12a provided at the one end. On the other hand, the annular protrusion 12c at the other end of the grommet 12 is in contact with the outer peripheral surface of the lead-out portion 10a of the position sensor 10.

Therefore, since the grommet 12 is elastically deformed in the direction perpendicular to the axis line while maintaining the above-mentioned state, the position sensor 10 mounted on the cylinder head 3 and the position on the timing cover case 9 are positioned. Even if there is a relatively large dimensional error in the relative positional relationship with the through hole 9b that is bored to penetrate the lead portion 10a in the sensor 10, this dimensional error can be reliably absorbed. Of.

By providing an annular groove 12d at the base of the boss 12a of the grommet 12, the elasticity of the grommet 12 is improved.
Since the length dimension of 2 can be increased without increasing the length dimension, a larger dimension error can be absorbed without increasing the size of the grommet 12. Further, as in the above-described embodiment, by disposing the position sensor 10 substantially directly below the timing pulley 6 and at a portion sandwiched by the timing belt 7 wound around the timing pulley 6, this position For sensor 10,
Since the other object is not easily touched, it is possible to reliably prevent the detection error from occurring due to the contact of the other object with the position sensor 10.

Further, as in the above embodiment, the timing cover case 9 is provided with the recess 9a, and the drawer portion 10a of the position sensor 10 is configured to project into the recess 9a. In addition to preventing contact of another object with the position sensor 10, there is an advantage that the position sensor 10 can be prevented from protruding from the timing cover case 9.

[Brief description of drawings]

FIG. 1 is a side view showing an embodiment of the present invention.

FIG. 2 is a sectional view taken along line II-II of FIG.

FIG. 3 is an enlarged cross-sectional view in a disassembled state.

[Explanation of symbols]

1 Internal Combustion Engine 2 Cylinder Block 3 Cylinder Head 4 Cylinder Head Cover 5 Cam Shaft 6 Timing Pulley 7 Timing Belt 8 Disc 8a Notch 9 Timing Cover Case 9a Recess 9b Through Hole 10 Position Sensor 10a Position Sensor Drawer 12 Grommet 12a Boss Part 12b Annular groove 12c Annular protrusion 12d Annular groove

Claims (1)

[Claims] 1. An internal combustion engine having a cam shaft on an upper surface, and a position sensor for detecting a power transmission wheel fitted to the cam shaft or a notch or a protrusion provided on a disc attached to the power transmission wheel,
In a detection device in which a lead-out portion of an electric wire in the position sensor is attached so as to project from a through hole formed in a timing cover case that covers the power transmission wheel, the detection device is formed of a soft elastic body such as rubber into a tubular shape. The grommet is fitted to the drawer portion of the position sensor, and one end of this grommet is attached to the inner peripheral edge of the through hole formed in the timing cover case at the outer peripheral portion thereof, while the inner periphery of the other end of the grommet is attached. A detection device for an ignition timing, etc. in an internal combustion engine, characterized in that an annular projection portion, which comes into contact with the outer peripheral surface of the pull-out portion of the position sensor, is integrally provided in the.