JPS6339422Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a dust-proof structure of a reduction mechanism portion of an internal reduction type starter.

Figure 1 shows a conventional starter of this kind. In the figure, 1 is an internal reduction type starter, 2 is a DC motor, 3 is an intermediate machine frame, 4 is a front machine frame, and the rear of the intermediate machine frame 3. A DC motor 2 is attached to the end face,
The front end surface is integrally screwed to the front machine frame 4 with bolts (not shown). 5 is a yoke of the DC motor, 6 is a field pole fixed to the inner peripheral surface of this yoke, and 7 is an armature of the DC motor 2, in which the front end of the armature rotating shaft 8 is It protrudes through the intermediate machine frame 3 and is rotatably supported by a ball bearing 9 fitted in the intermediate machine frame 3. 1
0 is a spur gear formed at the front end of the armature rotating shaft 8, and is engaged with a large gear 12 that is spline-engaged on a pinion shaft (output rotating shaft) 11 and is driven. Reference numeral 13 denotes an overrunning clutch that is spline-engaged with a helical spline (not shown) formed on the pinion shaft 11 so as to be able to slide back and forth, and the overrunning clutch 13 is connected to the front end so that the pinion 14 is engaged with a unidirectional rotational force. It will be installed. Reference numeral 15 denotes a shift lever whose end is cam-engaged with the cam-engaging groove 13a of the overrunning clutch 13, and an electromagnetic switch (not shown) is attached to the other end (upper end).
It rotates around the rotation fulcrum portion 15a. 16 is a lever spring that presses the shift lever 15, 17
18 and 19 are sleeve bearings fitted into the intermediate machine frame 3 and the front machine frame 4, respectively, and pivotally connect the front and rear ends of the pinion shaft 11. It has a bearing.

Next, the operation of the above configuration will be explained. When the shift lever 15 is biased to rotate in the counterclockwise direction in the figure about the pivot point 15a by an electromagnetic switch (not shown), the overrunning clutch 13, which is cam-engaged with the shift lever 15, is rotated on the pinion shaft 11. It is transferred forward (to the right in the figure), and the pinion 14 is engaged with a ring gear of an internal combustion engine (not shown). At the same time, the DC motor 2 is energized to generate rotational force, which is increased (the rotational speed is reduced) and transmitted to the pinion shaft 11 . This rotational force is then transmitted to the pinion 14 via the overrunning clutch 13, driving the ring gear and starting the internal combustion engine. After the engine is started, the shift lever 15 is returned to the state shown in the figure, the overrunning clutch 13 moves backward on the pinion shaft 11 (moves to the left in the figure), and the pinion 14 is disengaged from the ring gear, returning to the state shown and standing still.

The conventional device is configured as described above, but in this configuration, the reduction gear (consisting of the spur gear 10 and the large gear 12) is of an open configuration, so it is prone to dirt, abnormal wear of the teeth, etc. , there were drawbacks such as high meshing noise.

This idea was made in order to eliminate the drawbacks of the conventional device as described above, and the purpose was to provide the above-mentioned reduction gear with a dust-proof structure and to have the excellent effects described below. There is.

An embodiment of this invention will be described below with reference to the drawings. First, in FIG. 2, reference numeral 21 denotes an intermediate machine frame installed in place of the intermediate machine frame 3 described in the conventional device shown in FIG. 22 are arranged. Next, FIG. 3 shows an internal reduction type starter 20 in which the intermediate machine frame of FIG. 2 is incorporated into the conventional device of FIG. A disk 23 is fitted on the pinion shaft 11 between the large gear 22 and the overrunning clutch 13, and the pinion shaft 11 [or the large gear 12]
It rotates as one. This disc 23 is connected to the inner circumferential wall surface of the front machine frame 4 and the protruding portion 22 of the intermediate machine frame 21.
It is arranged so as to form a minute gap (labyrinth seal) on the side end surface of. The rest of the configuration is the same as that of the conventional device shown in FIG. 1, so the explanation will be omitted.

With the above configuration, the reduction mechanism consisting of the spur gear 10 and the large gear 12 is sealed and dust-proof, and the life of the device is extremely extended. Prevents oil from scattering,
This has the effect of reducing meshing noise.

In the above-mentioned embodiment, a case has been described in which the speed reduction device is constituted by an external gear meshing gear device, but the same effect can be obtained even if the speed reduction device is an internal gear meshing type speed reduction device.

As described above, according to this invention, a dust-proof structure is constructed in which the gear reduction mechanism is surrounded by the protruding portion 22 and the disc 23, which provides excellent effects such as increasing device life, reliability, and reducing meshing noise. This has the effect that it can be obtained with a simple configuration and at low cost.

[Brief explanation of the drawing]

Fig. 1 is a sectional view of the main parts of a conventional device, Fig. 2 is a front view a and a sectional view b of the intermediate machine frame, which is the main component of this invention, and Fig. 3 is a sectional view taken along the line B-B. FIG. 2 is a sectional view of a main part of an internal reduction type starter according to an embodiment. In the figure, 4 is the front machine frame, 8 is the armature rotating shaft, and 10
is a spur gear, 11 is a pinion shaft, 12 is a large gear, 1
3 is an overrunning clutch, 21 is an intermediate machine frame, 22 is a protrusion, and 23 is a disc. Note that the same reference numerals in the figures indicate the same or corresponding parts.

Claims (1)

[Scope of utility model registration request] A reduction gear device is installed between the output rotating shaft, which is mounted between the front machine frame and the intermediate machine frame, and whose both ends are supported, and the rotating shaft of the DC motor, which is attached to the intermediate machine frame. and has an overrunning clutch that is spline-engaged with a helical spline formed on the output rotating shaft so as to be slidable back and forth, wherein a cylindrical protrusion projecting in the axial direction is provided on the intermediate machine frame. The gear is positioned between the reduction gear and the overrunning clutch, and its central portion is fitted onto the output rotating shaft, and its outer peripheral portion is fitted onto the front machine frame. An internal reduction type starter characterized by comprising a disc disposed so as to form a minute gap between the inner wall surface of the cylindrical projection and the side end surface of the cylindrical protrusion.