JPS645974Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an improvement of a small geared electric motor.

Previously, Utility Model Application Publication No. 156104, Utility Model Application Publication No. 54
- As disclosed in Publication No. 124917, a small electric motor body having a rotor pinion on the rotor shaft,
A gear box with a gear that meshes with the rotor pinion is separately formed inside, and the small electric motor body and gear box are combined to mesh the rotor pinion and the gear, thereby transmitting the rotation of the rotor shaft to the gear. A small electric motor with a gear is known.

In this type of small geared electric motor, in order to transmit the rotation of the rotating shaft to the gear, it is required that the peaks and valleys of the rotor pinion and the gear mesh reliably. However, with conventional small electric motors with gears,
This point is not taken into consideration at all, and the structure relies solely on the skill of the assembler, so the peaks and troughs of the rotor pinion and gear may not mesh reliably, and the rotation shaft Small electric motors with gears may have trouble starting because the rotation is not transmitted to the gears.

Further, if the rotor pinion and the gear are forced to mesh with each other, the tooth tips may be damaged and the shaft may be broken.

The present invention was devised in view of the drawbacks of the prior art described above, and the purpose of the present invention is to ensure that the rotor pinion and the gear can mesh when the small electric motor body and the gearbox are connected. The purpose of the present invention is to provide a small electric motor with a gear.

The feature of the present invention is that the rotor pinion and the gear are shallowly meshed in the width direction of the teeth, and then the rotor pinion and the gear are rotated to mesh deeply in the width direction of the teeth.

Embodiments of the present invention will be described below with reference to the drawings.

1 to 6 show a first embodiment of a small geared electric motor according to the present invention. In the figures, 1 is the small electric motor main body, and 2 is a gear box. The small electric motor main body 1 has a main body case 3, a rotor 4, a core plate 5, and a coil bobbin 6, and the coil of the coil bobbin 6 is connected to a lead wire 7. A plurality of hooks 8 are formed at equal intervals on the upper end of the main body case 3.
The core plate 5 has fitting holes 9 and 10 for the rotor 4.
are formed at symmetrical positions with respect to the axis of the The rotor 4 has a rotor shaft 11, and a rotor pinion 13 integrally having a reverse rotation prevention pawl 12 is press-fitted into the rotor shaft 11. The gearbox 2 is provided with a rotation transmission mechanism 14 as shown in FIG. This rotation transmission mechanism 1
4 is composed of a two-stage gear 15, an intermediate gear 16, and an output gear 17, and the rotation of the two-stage gear 15 is as follows.
is transmitted to the output gear 17 via the intermediate gear 16,
It is adapted to be taken out from the output shaft 18 shown in FIGS. 1 and 2. A rotor bearing 19 is formed in the center of the gearbox 2, and a gear 20 forming a part of the two-stage gear 15 can mesh with the rotor pinion 13. The gearbox 2 has a mounting portion 21 as shown in FIGS. 1 to 4, and a relief portion 22 is formed on the outer periphery of the gearbox 2 in the circumferential direction as a means for allowing relative rotation. , as shown in FIG. 3, the angle θ of the relative rotation direction of this relief portion 22
is determined by the ratio of the number of teeth between the rotor pinion 13 and the gear 20, and is approximately 36 degrees here.
A stepped portion 23 that engages with the hook 8 is formed at the final position of the relief portion 22 in the relative rotation direction, and the hook 8 and the stepped portion 23 are at a relative rotation stop position between the small electric motor main body 1 and the gear box 2. It constitutes a coupling means for coupling the small electric motor main body 1 and the gearbox 2. That is, by bending the hook 8 and bringing it into contact with the stepped portion 23, the small electric motor main body 1 and the gear box 2 are connected inseparably. A small protrusion 24 and a large protrusion 25 are formed on the gear box 2 at symmetrical positions on the center line passing through the rotor bearing 19 and with the rotor bearing 19 in between. A cover plate 26 is provided on the upper surface of the gear box 2. The cover plate 26 is formed with a central hole 26', bearing holes 27, 28, 29, and protrusion insertion holes 30, 31, respectively.
The output shaft 18 of No. 7 is supported in the bearing hole 27, the shaft 32 of the intermediate gear 16 is supported in the bearing hole 29, and the shaft 33 of the two-stage gear 15 is supported in the bearing hole 28. The large protrusion 25 is inserted into the protrusion insertion hole 30, and the large protrusion 25 is inserted into the cover plate 2 as shown in FIG.
6 , a small projection 24 is inserted into the projection insertion hole 31 , and the small projection 24 projects from the cover plate 26 . The rotor pinion 13 is configured to protrude into the gearbox 2 through the central hole 26', and the small projection 24 and the large projection 25 cooperate with the flat surface of the core plate 5 to connect the small electric motor main body 1 and the gearbox 2. During relative rotation with the rotor pinion 13 and the gear 20, the rotor pinion 13 and the gear 20 are meshed shallowly in the direction of their tooth widths, and this meshing state is maintained. and large protrusion 25
The peripheral walls of the insertion holes 9 and 10 constitute a relative rotation prevention means that abuts against the small protrusion 24 and the large protrusion 25 to prevent relative rotation between the small electric motor main body 1 and the gear box 2. , insertion holes 9, 10
is a meshing state transition in which the rotor pinion 13 and gear 20 shift from a shallowly meshed state in the tooth width direction to a deep meshed state in the tooth width direction by the relative rotation between the small electric motor main body 1 and the gearbox 2. It functions as a means.

FIG. 6 shows a state in which the rotor pinion 13 and the gear 20 according to the present invention are shallowly meshed in the tooth width direction.
In a state where the small electric motor main body 1 and the gear box 2 are relatively rotated in a state in which the rotor pinion 13 and the gear 20 are in shallow mesh, the rotor pinion 13 and the gear 20 are meshed securely, and then the rotor pinion 13 and the gear 2 are
Since the rotor pinion 13 and the gear 20 are deeply meshed in the tooth width direction, the rotor pinion 13 and the gear 20 can be reliably meshed without damaging the tooth tips of the rotor pinion 13 and the gear 20.

FIG. 7 shows another embodiment of the geared small electric motor according to the present invention, in which a cut groove 34 is provided on the inner peripheral wall of the gear box 2, and a protrusion is provided on the outer periphery of the small electric motor main body 1 (not shown). By engaging the protrusion with the cut groove 34, the small electric motor main body 1 and the gear box 2 are connected.
When the protrusion (not shown) engages with the inner deep part 35 of the cut groove 34,
The relative rotation between the small electric motor main body 1 and the gearbox 2 is stopped, and the rotor pinion 13 and the gear 20 are deeply connected.

As explained above, according to the present invention, after the rotor pinion and gear are slightly and shallowly meshed in the direction of their face widths, they are rotated relative to each other to ensure meshing, and then the rotor pinion and gear are Since they are deeply engaged in the tooth width direction, the two can be reliably engaged without damaging the tooth tips. Furthermore, the assembly work of the small electric motor with gears becomes easier.

[Brief explanation of the drawing]

Fig. 1 is an exploded perspective view of a small electric motor with a gear according to the present invention, Fig. 2 is a perspective view showing the coupled state of the small electric motor with a gear according to the present invention, and Fig. 3 is a plan view of a gear box according to the present invention. , Fig. 4 is a side view of the gearbox shown in Fig. 3, Fig. 5 is a plan view showing the gearbox shown in Fig. 3 with a cover plate attached, and Fig. 6 shows the rotor pinion and gears. FIG. 7 is a perspective view showing another embodiment of the gearbox according to the present invention. 1... Small electric motor body, 2... Gear box, 4... Rotor, 5... Core plate, 8...
Hook, 9, 10... Fitting hole, 11... Rotor shaft, 13... Rotor pinion, 20... Gear, 2
2...Relief portion, 23...Stepped portion, 24...Small protrusion, 25...Large protrusion.

Claims (1)

[Claims for Utility Model Registration] A small electric motor body having a rotor pinion on a rotor shaft and a gear box having a gear meshing with the rotor pinion are formed separately,
A small electric motor with a gear, in which the small electric motor main body and the gearbox are coupled, the rotor pinion and the gear are meshed, and the rotation of the rotor shaft is transmitted to the gear. means for allowing relative rotation with a gearbox; and mesh maintenance for causing the rotor pinion and the gear to engage shallowly in the tooth width direction and maintaining the meshing state during the relative rotation between the small electric motor main body and the gearbox. means, provided in a relative rotation range between the small electric motor main body and the gearbox, for shallowly meshing the rotor pinion and the gear in the tooth width direction by the relative rotation between the small electric motor main body and the gearbox; meshing state transition means for shifting from a state in which the rotor pinion and the gear are deeply engaged in the direction of the tooth width; and a state in which the small motor main body and the gear box A small electric motor with a gear, comprising: relative rotation prevention means for preventing relative rotation; and coupling means for coupling the gearbox and the small electric motor main body at a relative rotation stop position between the gearbox and the small electric motor main body.