JPS6039583Y2 - Dustproof cover for rotating shaft - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a dustproof cover having an insertion hole for a rotating shaft that can penetrate through various machines and protrude to the outside.

Conventionally, in various machines, in order to prevent dust from entering the insertion hole of the rotating shaft of a housing in which the rotating shaft protrudes to the outside, it is necessary to prevent the rotating shaft insertion hole of the housing from coming into contact with the rotating shaft. There are two ways to prevent dust: one method is to reduce the gap between the two, and the other is to make the gap close to each other using an elastic member using a lubricant or the like to eliminate the gap.

However, in the former case, although it is simple and the manufacturing cost is low, there are restrictions on how small the gap can be made due to the precision of work between the casing and the rotating shaft, and it is difficult to make the gap small enough for dust prevention. It was difficult.

On the other hand, in the latter case, the rotating shaft and the elastic member on the casing side are constantly in contact with each other with tension, so there are drawbacks such as wear of the rotating shaft and deterioration of the elastic member, and the manufacturing cost is high. There were drawbacks such as high price.

The present invention was developed in view of the above circumstances, and provides a dustproof cover for the rotating shaft that can minimize the gap between the housing and the rotating shaft without causing elastic contact. This is what we intend to provide.

The dustproof cover for the rotating shaft according to the present invention has a through hole with a diameter larger than the rotating shaft in the main body of the cover which has a mounting part on the outer periphery, and a through hole for the rotating shaft is bored in the through hole. It is made up of a synthetic resin annular plate that is movable in the radial direction and detachably attached.

The following is an example of a dustproof cover for a rotating shaft according to the present invention, which covers the point of a magneto provided between the flywheel and the crankcase in a spark ignition engine in which a flywheel is attached to a crankshaft protruding from the crankcase. Let me explain the case.

First, the structure of the dustproof cover will be explained using a diagram.
As shown in Figure 1a, the dustproof cover main body 1 has a circular hole 2 at opposite positions on its outer periphery, into which a screw is inserted, and a through hole 3 with a larger diameter than the crankshaft in the center. and the through hole 3
As shown in FIG. 1, a synthetic resin annular plate 5 having a hole 4 through which the crankshaft is inserted is attached so as to be movable in the radial direction and detachable as shown in FIG.

The annular plate 5 made of synthetic resin in this example has a larger diameter than the through hole 3 as shown in FIG. At equiangular triangular positions on the outer circumferential side of the protrusion 6, a tongue piece 7 that locks onto the back surface of the inner circumferential edge of the through hole 3 is provided, and furthermore, on the outer circumferential side of the annular protrusion 6, a part of the inner circumferential edge of the through hole 3 is provided. A rectangular engaging member 8 is provided which engages with a groove 3a that is cut into a rectangular shape.

To explain the procedure for attaching such an annular plate 5 made of synthetic resin to the through hole 3 of the cover body 1, first insert one tongue piece 7 on either the left or right side adjacent to the engaging member 8 on the back side into Raa. After positioning and positioning the other two tongue pieces 7 in the through hole 3, the outer peripheral edge of the annular plate 5 is pressed from the groove 3a side, and the two tongue pieces that were located in the through hole 3 are removed. 7 is locked to the back surface of the inner peripheral edge of the through hole 3.

Next, the annular plate 5 is rotated while being pressed from the front, and as shown in FIG. Fit and lock inside 3a.

In this way, a dustproof cover consisting of a synthetic resin annular plate 5 is fitted into the through hole 3 of the cover main body 1, and the tip of the crankshaft 11 protruding from the crankcase 10 shown in FIGS. 3 and 4 is fitted. is flywheel magneto flywheel 12
is fitted and fixed, and a point 13 of a flywheel magnet is provided on the outer circumferential side of the crankshaft 11 between the flywheel 12 and the crankcase 10.

The dustproof cover of the present invention covers the point 13 and the bearing part of the crankshaft 11 to prevent dust. Fit the cover body 1 onto the crankshaft 11, align the circular hole 2 on the outer periphery of the cover body 1 with the screw hole provided on the outer surface of the crankcase 10, and screw the screw 15 into this to crank the cover body 1. It is fixed to the outer surface of the case 10.

At this time, even if there are variations in the position of the screw hole on the outer surface of the crankcase 10 to which the cover body 1 is attached and the position of the crankshaft 11 during assembly, the dustproof cover of the present invention can be used with the cover body 1. Since the annular protrusion 6 on the back surface of the annular plate 5 attached to the through hole 3 has a smaller diameter than the through hole 3, the annular plate 5 can move in the radial direction within the through hole 3, and conversely, the cover body can move in the radial direction. 1 can be moved in the direction of the outer circumference of the annular protrusion 6 of the annular plate 5 through the through hole 3, so that the above-mentioned variations can be absorbed and the assembly can be easily and reliably mounted.

Thereafter, the annular plate 5 is immediately moved very slightly in the radial direction within the through hole 3 by the rotation of the crankshaft 11, and settles in a predetermined position, so that the annular plate 5 is not disposed between the crankshaft insertion hole 4 and the crankshaft 11. Since the minimum gap is maintained, there is no hindrance to the rotation of the crankshaft 11, and the annular plate 5
will not wear out.

In addition, since the gap between the crankshaft insertion hole 4 and the crankshaft 11 is the minimum necessary gap, dust that tries to enter through this gap is blown away by the rotation of the crankshaft 11, so there is a sufficient dustproof effect. .

In addition, in the dustproof cover of the present invention, the amount of mutual movement between the cover body 1 and the synthetic resin annular plate 5 is such that it can absorb variations in the mounting position of the cover body and the position of the crankshaft 11 during assembly. It is enough.

As detailed above, the dustproof cover for the rotating shaft according to the present invention simultaneously positions the mounting part on the outer periphery of the cover and the cover mounting part of the casing, as well as the rotating shaft insertion hole of the cover and the rotating shaft protruding from the casing. Since they can be aligned, even if there are variations in the positions of the cover attachment part and the rotating shaft due to machining and assembly, the cover can be easily and securely attached without any problems.

Furthermore, since the gap between the rotary shaft insertion hole and the rotary shaft can be suppressed to the necessary minimum, the rotary shaft insertion hole is not worn out and there is a sufficient dustproof effect.

[Brief explanation of the drawing]

Fig. 1a is a rear perspective view of the cover main body in an embodiment of the dustproof cover of the present invention; Fig. 1 is a rear perspective view of an annular plate attached to the through hole of the cover main body; Fig. 2 1 is a rear perspective view showing an embodiment of the dust-proof cover obtained by attaching the annular plate shown in FIG. 1 to the through hole of the cover body shown in FIG. FIG. 4 is a longitudinal cross-sectional view showing a state in which the crankshaft protrudes from the crankshaft is fitted and attached to the outer surface of the crankcase, and FIG. 4 is a view taken along the line A--A in FIG. 3. 1...Cover body, 2...Circular hole, 3.
...Through hole, 3a...Rectangular notch groove, 4.
... Crankshaft insertion hole, 5 ... Synthetic resin annular plate, 6 ... Annular projection, 7 ... Tongue piece, 8 ... Rectangular engagement member 10...
Crankcase, 11...Crankshaft, 12-
------Flywheel, 13... points, 15... screws.

Claims (1)

[Scope of utility model registration request] Dust-proof covers are designed to prevent dust from entering through the gap between the casing and the rotating shaft of various machines, and the mounting part is installed on the outer edge of the rotating shaft to maintain the minimum gap necessary for dust-proofing in the center. The cover body is made of synthetic resin and has a hole with a diameter larger than that of the main body, an annular projection with a diameter smaller than the hole on the back with a rotation shaft insertion hole, and a tongue piece on the outer periphery of this annular projection. A dustproof cover for a rotating shaft portion, characterized in that the annular plate is movable in the radial direction and detachably attached to the through hole using the tongue piece.