JPS5834265A - Device for fixing gear to rotary shaft - Google Patents

Abstract

PURPOSE:To enhance a fixing workability by forming an indentation on the outer periphery of a boss projecting from the one end surface of a gear and a projection on the inner periphery thereof respectively, and by putting said projection into an annular groove formed on the outer periphery at one end of a rotary shaft. CONSTITUTION:In the case of fixing a gear on a rotary shaft, for example in a distributor 1 of an ignition unit for an internal-combustion engine, a rotary shaft 10 is supported rotatably with bearings 8, 9 on the upper and lower opening portion of a cylinder 7 projecting from a lower end surface of a housing body 3. A narrow annular groove 11 is formed on the lower end portion of a first shaft portion 101 of said shaft 10. On the other hand, at least one indentation 15 is formed in plastic deformation with a punch (not shown) having a larger diameter than said groove 11, on the outer periphery of a boss 13 protruding from the upper end surface of a driven gear 12, and a projection 16 is formed similarly on the inner periphery thereof, respectively. By putting said projection 16 into said groove 11, said gear 12 can be fixed immovably in the axial and rotating direction on said shaft 10, thereby facilitating a fixing operation.

Description

[Detailed description of the invention] The present invention relates to a device for fixing a gear to a rotating shaft.

For example, in a power distributor for an ignition system for an internal combustion engine.

When fixing a driven gear to which power is transmitted from the camshaft of an engine to one end of the rotating shaft of the pulse generator that protrudes from inside the housing, conventionally, a boss portion protruding from one end surface of the driven gear is attached to the rotating shaft. A series of through holes are formed in the boss part and the rotating shaft to fit into the protrusion, and a spring pin is inserted into the through holes to prevent the driven gear from slipping out and rotating. However, the work of aligning the holes and inserting the spring bin is troublesome.

It takes a lot of effort to fix the driven gear.

In view of the above, an object of the present invention is to provide a device for fixing a gear to a rotating shaft, which fixes a gear such as a driven gear to the rotating shaft using plastic deformation means to facilitate the fixing operation of the gear. .

Hereinafter, an embodiment in which the present invention is applied to a power distribution device for an ignition system for an internal combustion engine will be explained with reference to the drawings. In FIG. The camp 4 is fixed to the housing main body 3 with a screw 6 via a seal member 5. The housing body 3 has a cylindrical portion T projecting from its lower surface, and bearings 8 and 9 made of oil-impregnated bearing metal are fitted into the upper and lower openings of the cylindrical portion 7, respectively. The rotating shaft 10 is attached to the bearings 8 and 9.
A first shaft portion 101 is rotatably supported with its lower end protruding outside the cylindrical portion 7 and its upper end projecting into the nosing body 3. The second shaft portion 102 of the rotating shaft 10 is rotatably fitted to the upper end portion of the first shaft portion 10□.

The moving gear 1 is attached to the protruding lower end of the cylindrical portion 7 of the first shaft portion 10□.
A boss portion 13 protruding from the upper end surface of 2 is fitted with a washer 14 interposed therebetween. Then, on the outer peripheral surface of the boss portion 13, at least one recess 15 is formed at a position corresponding to the annular groove 11 by plastic deformation using a punch (not shown) having a diameter larger than the width of the annular groove 11, and the recess A convex portion 16 formed on the inner circumferential surface of the boss portion 13 corresponding to the groove 15 is bitten into the annular groove 11 and its bottom surface, and at the same time, both edges of the annular groove 11 are slightly bulged inward, whereby the driven gear 12 The rotation axis 1
0 so that it cannot move in the axial and rotational directions.

In this way, in order to fix the driven gear 12, it is sufficient to press the outer circumferential surface of the boss portion 13 corresponding to the annular groove 11, and this corresponding position can be easily indexed using a jig. The work of fixing the driven gear 12 is extremely easy. Furthermore, even if there are variations in the machining accuracy of the cylindrical portion 7, rotating shaft 10, boss portion 13, etc., and the protruding length of the rotating shaft 10 from the cylindrical portion I, the length of the boss portion 13, etc. By interposing the washer 14 between the end face of the boss portion 13 and the end face of the bearing 9, the driven gear 12 can be reliably fixed to the rotating shaft 10 by maintaining an appropriate gap therebetween.

A driving gear (not shown) fixed to the camshaft of the internal combustion engine is engaged with the driven gear 12 of the rotating shaft 10.
The power is transmitted from the camshaft.

Inside the housing body 3, the second shaft portion 1 of the rotating shaft 10
0. The surrounding pulse generator P is configured as follows. That is, an annular substrate 18 is placed on an annular stepped portion 17 formed on the inner peripheral surface of the housing main body 3, and a pair of protrusions 19 ( (only one of which is shown in the figure) engages with a pair of notch grooves 20 formed in the housing body 3. A synthetic resin annular body 23 is fixed to the upper surface of the substrate 18, in which a pair of magnets 21 such as ferrite and a magnet substrate 22 are embedded in opposing positions. The pink amplifier coil 24 is fitted into the space formed by the inner circumferential surface of the annular body 23 and the projecting edge protruding inward from the upper edge thereof, and thereby the pick amplifier coil 24 is connected to the top and bottom. and prevented from moving circumferentially. 25.26 is pink up coil 24
The pair of lead wires 27 is a rubber annular gasket interposed between the lower surface of the pickup coil 24 and the upper surface of the substrate 18. Second shaft portion 10. A signal rotor 29 having a number of protrusions 28 corresponding to the number of cylinders of the internal combustion engine is fitted therein, and an annular stator 30 is concentrically arranged around the signal rotor 29 .

The stator 30 has projections 2 of the rotor 29 on its inner peripheral surface.
The inner ring 32 has a number of protrusions 31 corresponding to 8, and the outer ring 34 is attached to the outer periphery of the inner ring 32 via a ball bearing 33. 3α.

A non-magnetic collar 35 (only one is shown in the figure) is fitted into each of the notch grooves 20, and the stator outer ring 34 and the collar 35 are connected by the notch 35α on the inner surface thereof.
interference is prevented.

A non-magnetic screw 37 fitted with an elastic suppression plate 36 is attached to the collar 35.
is fitted and inserted, and by screwing the screw 37 into the housing main body 3, the board 18 is pressed and fixed to the housing main body 3 via the collar 35, while the outer ring 3 of the stator 30
4 is connected to the housing main body 30 via the elastic pressing plate 36 to the stepped portion 3
It is suppressed and fixed on a.

A known vacuum advance mechanism V connected to the intake manifold of the engine is provided on the side surface of the housing body 3, and the tip of an operating rod 38 operated by a diaphragm (not shown) is connected to the inner ring 32 of the stator 30. They are connected via pins 39.

A known centrifugal advance mechanism G is provided in the housing body 3 below the substrate 18 . The centrifugal advance mechanism G
a retaining plate 40 fixed to the first shaft portion 101; a pair of weight plates 41 rotatably attached to the retaining plate 40;
It includes a cam plate 42 fixed to the second shaft portion 102 and a pair of tension coil springs 43 connecting the cam plate 42 and the holding plate 40. Second shaft part 101
102 are connected via a centrifugal advance mechanism G.

A power distribution device is disposed at the top of the housing body 3, and a power distribution rotor 45 having a power distribution electrode 44 is connected to the second shaft portion 10.
It is fixed to the upper end of 2. The center electrode 46 of the cap 4 is in contact with the base of the power distribution electrode 44, and the tip end thereof is configured to protrude around the power distribution rotor 45 and face the plurality of side electrodes 47 of the cap 4 in sequence. Ru. The number of side electrodes 47 is provided corresponding to the number of cylinders of the engine.

In the pulse generator P, as described later, the signal rotor 29 and each protrusion 28, 31 of the stator 30 face each other, and then the ignition timing signal is generated by misalignment.
In response to this ignition timing signal, the high voltage generated on the secondary side of the ignition coil in the power distribution device must be distributed from the power distribution electrode 44 to each side electrode 47, so that the rotating shaft 10 can be rotated at a predetermined level when the engine is assembled. It has to be put into position. Further, the driven gear 12 and the drive gear on the camshaft side that drives the driven gear must be properly engaged with each other at a predetermined rotational position of the rotating shaft 10 and the camshaft.

Therefore, in the past, a reference mark was formed on the cylindrical portion 7, and an alignment mark was formed on the boss portion of the driven gear separately from the through hole, but in the present invention, the alignment mark is formed at the same time as the driven gear 120 is fixed to the rotating shaft 10. It can be performed.

That is, first, a reference mark M is placed on the outer peripheral surface of the cylindrical portion 7 near the opening.
are carved, the opposing positional relationships of the signal rotor 29 and stator 30 and the power distribution electrodes 44 and side electrodes 47 are determined appropriately, and then the rotating shaft 10 is fixed non-rotatably with a jig, and then the rotating shaft 10 is The boss portion 13 of the driven gear 12 is fitted through the washer 14, and the driven gear 12 is engaged with the gear of the jig, so that the reference mark M and the recessed portion 15 are positioned on a straight line parallel to the axis of the rotating shaft 10. The recessed portion 15 is formed to fix the driven gear 12 to the rotating shaft 10 so that the driven gear 12 can be fixed to the rotating shaft 10. As a result, the recess 15 functions as an alignment mark, and even if the rotating shaft 10 rotates after the driven gear 12 is fixed, the recess 15 can be aligned with the reference mark M during engine assembly, and the signal rotor 29, stator 30, and power distribution Opposing position of electrode 44 and side electrode 47 and driven gear 12
The engagement state with respect to the camshaft side drive gear is determined to be a proper state.

Next, to explain the operation of this embodiment, the signal rotor 29 is rotated via the rotating shaft 10 by a camshaft or the like,
When each protrusion 28 faces each protrusion 31 of the stator 30, the magnet 21, stator 30, signal rotor 2
9. Second shaft portion 102° A magnetic flux is formed between the substrate 18, the magnet substrate 22, and the magnet 21, and then the magnetic flux changes as the projections 28° and 31 are offset, so that a pulse-like voltage is applied to the pickup coil 24. occurs. The voltage causes the igniter unit (not shown) to operate to cut off the primary side of one ignition coil, so that a high voltage is generated on the secondary side of the ignition coil, and the high voltage is applied to the center electrode 46 and the power distribution electrode 44. It is distributed to the corresponding side electrode 4T via the spark plug, and causes a spark plug (not shown) to spark.

This ignition timing is determined by the first shaft portion 10. The rotation of the second shaft portion 10. is caused by the centrifugal advance mechanism G. Since the rotation speed of the signal rotor 29 is increased, the rotation speed of the signal rotor 29 is increased.
The angle is advanced by shortening the time from when each protrusion 28° 310 faces each other to the stator 30 until the next face. Further, since the inner ring 32 of the stator 30 is rotated by the vacuum advance mechanism V, the ignition timing is also advanced.

Note that the present invention is applicable not only to power distributors but also to fixing gears to rotating shafts in other devices.

As described above, according to the present invention, an annular groove is provided on the outer circumferential surface of one end of the rotating shaft, a boss portion protruding from one end surface of the gear is fitted to one end of the rotating shaft, and the outer circumferential surface of the boss portion is fitted into the one end of the rotating shaft. A part of the gear is pressed to form a concave portion, and a convex portion on the inner circumferential surface of the boss portion formed corresponding to the concave portion is bitten into the annular groove, so that the gear can be fixed to the rotating shaft by an extremely simple means. and has good workability. Further, since the annular groove of the rotating shaft is simply penetrated by the convex portion of the inner circumferential surface of the boss portion of the gear, there is no need for strict machining accuracy, and machining is extremely easy. Furthermore, the position corresponding to the annular groove on the outer circumferential surface of the boss can be easily indexed using a jig, and even if there is some variation in the length of the boss due to machining, the gear can be reliably aligned with the rotation axis. Can be fixed.

[Brief explanation of drawings]

The drawings show one embodiment of the present invention; FIG. 1 is a longitudinal side view, FIG. 2 is an exploded side view of the main parts before the gear is fixed, and FIG. 3 is a side view of the main parts after the gear is fixed. Figure 4 is Figure 1 IV-I
It is a sectional view taken along the V line. DESCRIPTION OF SYMBOLS 10... Rotating shaft, 11... Annular groove, 12... Driven gear, 13... Boss part, 15... Recessed part, 16...
Convex portion Fig. 1 Fig. 2 Fig. 3

Claims (1)

[Claims] An annular groove is provided on the outer peripheral surface of one end of the rotating shaft, a boss portion protruding from one end surface of the gear is fitted to one end of the rotating shaft, and a part of the outer peripheral surface of the boss portion is pressed to form four parts. A device for fixing a gear to a rotating shaft, in which a convex portion on the inner circumferential surface of the boss portion formed in correspondence with the concave portion bites into the annular groove.