JP7221728B2 - gear unit and electronics - Google Patents

Description

One aspect of the present invention relates to a gear unit and an electronic device including the gear unit.

2. Description of the Related Art In recent years, among drive devices mounted on small electronic devices, there are some that have a configuration in which a lead screw is mounted and an object is reciprocated in the axial direction of the lead screw. As an example of such a driving device, Patent Document 1 discloses a lens driving mechanism.

JP 2016-51075 A

In the configuration described in Patent Document 1, the base 10, the auxiliary member 16, the lens frame 30, the lead screw 41, and the motor 40 are provided, and the screw B connects the base and the auxiliary member. However, in such a conventional configuration, since the configuration is based on the assumption that the screws B are used for fixing, it may be difficult to further reduce the space.

The present invention employs the following means to solve the above problems. In the following description, reference numerals and the like in the drawings are added in parentheses to facilitate understanding of the invention, but each component of the present invention is not limited to these added descriptions. It should be interpreted broadly to the extent that a trader can technically understand.

One means of the present invention is
a motor (30) having an axially extending motor output shaft (31);
a lead screw (70) rotated by power transmitted from the motor output shaft (31);
a guide shaft (90) for guiding the lead screw;
a gear case (20) supporting the motor;
a frame (10) supporting the lead screw (70), the guide shaft (90) and the gear case (20);
a connector (11) that fixedly connects one side of the frame and the gear case;
the other side of the frame and the gear case are fixedly connected by the guide shaft (90a);
gear unit.

According to the gear unit having the above configuration, the connecting portion on the other side of the frame and the gear case is fixed and connected by the guide shaft. Therefore, since it is not necessary to connect the other side using a connecting tool such as a screw, a space for inserting the connecting tool is not necessary, and the overall space-saving configuration can be achieved.

In the above gear unit, preferably
A connector for connecting the frame and the gear case is not arranged on the other side.

In the above gear unit, preferably
further comprising a gear (50, 60) positioned between the motor output shaft and the lead screw;
The gear case further supports the gear.

According to the gear unit having the above configuration, it is possible to configure the gear unit in a space-saving manner while performing desired acceleration and deceleration using the gears.

In the above gear unit, preferably
The guide shaft extends in a direction substantially parallel to the axial direction.

According to the gear unit having the above configuration, since the guide shaft, the lead screw, and the motor output shaft are configured to extend in the same axial direction, the configuration can be made thin and compact.

In the above gear unit, preferably
Both ends of the guide shaft are press-fitted into holes formed in the frame.

According to the gear unit having the above configuration, the guide shaft can be fixed to the frame by pressing the guide shaft into the frame. Therefore, the configuration is simple and inexpensive without using welding or adhesive. can be

The present invention includes an electronic device including any one of the gear units described above.

According to such an electronic device, it is possible to configure, for example, a camera unit to be driven by a compact gear unit. Therefore, it is possible to reduce the size of the electronic device while configuring the camera unit and the like to be drivable.

It is a perspective view of a gear unit. It is a perspective view of a gear unit. It is a side view of a gear unit. FIG. 4 is a cross-sectional view of the gear unit at position AA in FIG. 3; It is an exploded perspective view of a gear unit.

In the gear unit of the present invention, the guide shaft is configured to connect the frame and the gear case while guiding the lead screw in the axial direction. One of the features is that it has a configuration that can be miniaturized.

An embodiment according to the present invention will be described according to the following configuration. However, the embodiment described below is merely an example of the present invention, and the technical scope of the present invention should not be construed in a limited manner. In addition, in each drawing, the same code|symbol is attached|subjected to the same component, and the description may be abbreviate|omitted.
1. Embodiment 2. Features of the present invention 3 . Supplementary matter

<1. embodiment>
Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following description, the same reference numerals in different drawings denote portions having the same function. Further, in the following description, the direction in which the output shaft of the motor extends is referred to as the axial direction, and the direction may be described with reference to the axial direction.

1 to 5 are diagrams showing a gear unit 1 of this embodiment. 1 and 2 are external perspective views of the gear unit viewed from different directions. FIG. 3 is a side view of the gear unit. 4 is a cross-sectional view taken along line AA in FIG. 3. FIG. FIG. 5 is an exploded perspective view of the gear unit.

As illustrated, the gear unit 1 of this embodiment includes a frame 10, a gear case 20, a motor 30, a planetary gear mechanism 40, a first gear 50, a second gear 60, a lead screw 70, bearings 81 and 82, washers 83a and 83b, fixture 84, guide shaft 90, and connector 11 are included.

<Motor 30>
The motor 30 is a DC motor, for example, and includes a plurality of terminals 32 and a motor output shaft 31 . As is well known, the motor 30 includes a rotor, a stator, and the like. The motor 30 is rotated by electric power supplied from the terminal 32, thereby rotating the motor output shaft 31. As shown in FIG. The motor output shaft 31 is connected to the sun gear 41 of the planetary gear mechanism 40 . The motor output shaft 31 extends in the axial direction, and a lead screw 70 and a guide shaft 90, which will be described later, are arranged parallel to the axial direction.

<Planetary gear mechanism 40>
The planetary gear mechanism 40 includes a sun gear 41 , three planetary gears 42 , a planetary carrier 43 and an output gear 44 .

The sun gear 41 is coaxial with the motor output shaft 31 and is connected to the motor output shaft 31 as described above. A gear is formed on the outer periphery of the sun gear 41 . Three planetary gears 42 arranged on the outer periphery of the sun gear 41 mesh with the gears of the sun gear 41 respectively. Each of the three planetary gears 42 has a gear on its outer periphery and a cylindrical through hole in its center. The gears of the planetary gear 42 are meshed with the inner peripheral gears of the internal gear (not shown). Cylindrical protrusions 43a of planetary carriers 43 are inserted into the through holes at the center of the three planetary gears 42, respectively. An output gear 44 formed coaxially with the planetary carrier 43 is arranged on the opposite side of the planetary carrier 43 from the planetary gear 42 . The output gear 44 has gears formed on its outer circumference, and meshes with a first large gear 52 of a first gear 50, which will be described later.

The planetary gear mechanism 40 is a conventionally known mechanism, and when the sun gear 41 rotates, it is accelerated and decelerated at a predetermined gear ratio, and the output gear 44 rotates.

<First gear 50>
The first gear 50 includes a first small gear 51 and a first large gear 52 . The first small gear 51 and the first large gear 52 are coaxial and have gears on their outer circumferences, and when one rotates, the other also rotates. The first large gear 52 meshes with the output gear 44 . That is, when the output gear 44 rotates, the first large gear 52 rotates, and accordingly the first small gear 51 rotates.

<Second gear 60>
The second gear 60 has gears on its outer periphery and meshes with the first small gear 51 . The second gear 60 is connected to a shaft 71 extending from the end of the lead screw 70 . The second gear 60, the lead screw 70, and the shafts 71 and 72 are coaxial. When the second gear 60 rotates, the shaft 71 rotates, and accordingly the lead screw 70 and the shaft 72 rotate.

<Lead screw 70>
The lead screw 70 is formed in a substantially cylindrical shape extending in a direction parallel to the axial direction, and a feed screw made of, for example, a trapezoidal screw is formed on the outer peripheral surface thereof. An object to be driven is arranged on the lead screw 70 so as to mesh with the feed screw, and when the lead screw 70 rotates, the object to be driven moves in the axial direction. When the lead screw rotates in one direction, the driven object moves in one axial direction, and when the lead screw rotates in the opposite direction, the driven object moves in the other axial direction.

<Bearings 81, 82>
The bearings 81 and 82 are arranged on one side and the other side of the lead screw 70, respectively, and support the lead screw 70 and the second gear 60 rotatably. The bearing 81 has a large diameter portion and a small diameter portion. A small diameter portion of the bearing 81 is inserted into the through hole 10 d of the frame 10 . The large-diameter portion of the bearing 81 contacts the frame 10 so that the bearing 81 does not slip out of the through hole 10d. The bearing 82 has a large diameter portion and a small diameter portion. A large diameter portion of the bearing 82 is inserted into the through hole 10 e of the frame 10 . Washers 83 a and 83 b are arranged on the outer side of the small diameter portion of the bearing 82 in the circumferential direction. A small diameter portion of the bearing 82 abuts on a fixture 84 with washers 83a and 83b interposed therebetween.

<Washers 83a, 83b>
The washers 83a and 83b are arranged between the bearing 82 and the fixture 84 to stably support the bearing 82 with respect to the fixture 84 without rattling.

<Guide shaft 90>
The guide shaft 90 is formed in a substantially cylindrical shape extending in a direction parallel to the axial direction, and is arranged on the side opposite to the motor 30 with respect to the lead screw 70 . The guide shaft 90 is arranged on the other side of the frame 10 opposite to the one side on which the connector 11 is arranged. Both ends 90a and 90b of the guide shaft 90 are inserted into through holes 10b and 10c formed in the frame 10, respectively. Both ends 90a and 90b of the guide shaft 90 are formed to have substantially the same size as the through holes 10b and 10c, and the both ends 90a and 90b of the guide shaft 90 are press-fitted into the through holes 10b and 10c. The guide shaft 90 is thereby fixed and connected to the frame 10 . One end 90 a of the guide shaft 90 is inserted into the hole 20 b of the gear case 20 . The end portion 90a is fitted into the hole portion 20b, but is not press-fitted. Therefore, the outer peripheral portion of the end portion 90a may have a margin with respect to the inner peripheral portion of the hole portion 20b.

<Frame 10>
The frame 10 is configured as a housing for the gear unit 1 . The frame 10 is made of metal. Frame 10 supports lead screw 70 , guide shaft 90 and gear case 20 . As will be described later, the gear case 20 supports components such as the motor 30 , so the frame 10 functions as a housing that supports the gear unit 1 as a whole.

The frame 10 has through holes 10a, 10b, 10c, 10d, and 10e. These through holes 10a, 10b, 10c, 10d, and 10e all extend circularly. Through holes 10b and 10c are formed coaxially. The through holes 10d and 10e are formed coaxially.

A connector 11 such as a screw is inserted into the through hole 10a. The through hole 10a is coaxial with the hole 20a of the gear case 20. As shown in FIG. The inner periphery of the through-hole 10a is formed with a screw thread that engages with the screw thread of the connector 11. As shown in FIG. Both ends 90a and 90b of the guide shaft 90 are inserted and fixed in the through holes 10b and 10c, respectively, as described above. A bearing 81 is inserted into the through hole 10d. A bearing 82 is inserted into the through hole 10e.

<Gear case 20>
The gear case 20 is made of resin. Gear case 20 supports motor 30 , planetary gear mechanism 40 , first gear 50 and second gear 60 . Gear case 20 is supported by frame 10 .

The gear case 20 has holes 20a and 20b. The hole portion 20a is a groove-like hole having a bottom portion, into which the connector 11 is inserted. A screw thread is formed on the inner periphery of the hole 20 a and is fitted with the screw thread of the connector 11 . The hole portion 20b is a hole extending along the axis of the guide shaft 90 from which a part of the outer circumference is removed. The hole portion 20b is fitted to the end portion 90a of the guide shaft 90 and supports the end portion 90a.

Note that the portion 20c near the end of the gear case 20 may be connected to the portion 10f of the frame 10 by a so-called snap-fit structure.

<Connector 11>
The connector 11 is inserted through the through hole 10 a of the frame 10 , inserted into the hole 20 a of the gear case 20 , and screw-fitted to the frame 10 and the gear case 20 . The connector 11 connects and fixes the vicinity of one end of the frame 10 and the gear case 20 by this screw fitting.

<Fixation structure between frame 10 and gear case 20>
As described above, the frame 10 and the gear case 20 are screw-fixed by the connector 11 at one end. On the other hand, the frame 10 and the other side of the gear case 20 are fixed by the guide shaft 90 as described above.

In addition, if the 20c portion of the gear case 20 and the 10f portion of the frame 10 are connected by a snap-fit structure as described above, the frame 10 and the gear case 20 can be connected more firmly without rattling. It is preferable because it becomes possible.

<2. Features of the present invention>
The present invention, which has been described by exemplifying one embodiment, has the following features.

The gear unit 1 of the above-described embodiment has a configuration in which the frame 10 and the gear case 20 are connected and fixed by a connecting member 11 on one side and connected and fixed by a guide shaft 90 on the other side. In this way, since the guide shaft 90 has the function of connecting the frame 10 and the gear case 20, it is not necessary to connect both sides with screws as in the conventional configuration. Therefore, a space for arranging the connecting member on the other side is not required, and a space-saving gear unit can be configured as a whole.

In the gear unit 1 of the above embodiment, the first gear 50 and the second gear 60 are arranged between the motor output shaft 31 and the lead screw 70, and the gear case 20 connects the first gear 50 and the second gear 60. It is configured to support. With this configuration, it is possible to configure the gear unit in a space-saving manner while performing desired acceleration and deceleration using the gears.

In the gear unit 1 of the above embodiment, the guide shaft 90 extends in a direction parallel to the axial direction of the motor output shaft 31 of the motor 30 . With this configuration, the guide shaft 90, the lead screw 70, and the motor output shaft 31 extend in the same axial direction, so that a thin and compact gear unit can be configured.

In the gear unit 1 of the above embodiment, both ends 90a and 90b of the guide shaft 90 are press-fitted into the through holes 10b and 10c of the frame 10, respectively. With this configuration, the guide shaft 90 can be fixed to the frame 10, so that a simple and inexpensive gear unit can be configured without using welding or adhesive.

Alternatively, both ends 90a and 90b of the guide shaft 90 are inserted into the through holes 10b and 10c of the frame 10, respectively, and the guide shaft 90 is fixed to the frame 10 by adhesion or welding.

The gear unit 1 of the above embodiment is mounted on mobile electronic devices such as smart phones, tablet devices, or notebook PCs in order to drive a camera unit or the like mounted on these mobile electronic devices. According to such an electronic device, it is possible to reduce the size of the electronic device while configuring the camera unit and the like to be drivable.

<3. Supplementary matter>
The specific description of the embodiment of the present invention has been given above. The above description is merely one embodiment, and the scope of the present invention is not limited to this one embodiment, but is interpreted broadly to the extent that a person skilled in the art can comprehend.

In the above embodiment, a configuration example in which the frame 10 is made of metal and the gear case 20 is made of resin has been described, but the configuration is not limited to this. 20 may be metal. However, the frame 10 into which the guide shaft 90 is press-fitted is preferably made of metal.

In the above embodiment, the configuration including the planetary gear mechanism 40 has been exemplified and explained, but a configuration that does not include the planetary gear mechanism is also possible. Moreover, it is good also as a structure provided with well-known acceleration/deceleration mechanisms other than a planetary gear mechanism.

In the above embodiment, the configuration including the first gear 50 and the second gear 60 has been exemplified and explained, but the type and number of such gears can be changed arbitrarily.

In the above embodiment, the DC motor was described as an example of the motor 30, but the motor 30 can adopt a motor other than the DC motor.

In the above embodiment, the connector 11 is described as a screw, but a rivet or the like may be used as the connector.

INDUSTRIAL APPLICABILITY The present invention is suitably used as a gear unit having a lead screw for driving a camera mounted on a smart phone.

DESCRIPTION OF SYMBOLS 1... Gear unit 10... Frame 10a, 10b, 10c, 10d, 10e... Through hole 11... Connector 20... Gear case 20a, 20b... Hole 30... Motor 31... Motor output shaft 32... Terminal 40... Planetary gear mechanism 41 ...Sun gear 42...Planetary gear 43...Planetary carrier 43a...Protrusion 44...Output gear 70...Lead screw 71, 72...Shafts 81, 82...Bearings 83a, 83b...Washers 84...Fixers 90...Guide shafts

Claims (6)

a motor having an axially extending rotating shaft;
a lead screw rotated by power transmitted from the rotating shaft;
a guide shaft that guides the lead screw;
a gear case supporting the motor;
a frame that supports the lead screw, the guide shaft, and the gear case;
a connector that fixedly connects one side of the frame and the gear case;
the other side of the frame and the gear case are fixedly connected by the guide shaft;
gear unit. A connector for connecting the frame and the gear case is not disposed on the other side,
A gear unit according to claim 1. further comprising a gear disposed between the rotating shaft and the lead screw;
the gear case further supports the gear;
A gear unit according to claim 1 or claim 2. The guide shaft extends in a direction substantially parallel to the axial direction,
A gear unit according to any one of claims 1 to 3. Both ends of the guide shaft are press-fitted into holes formed in the frame, respectively.
A gear unit according to any one of claims 1 to 4. An electronic device comprising the gear unit according to any one of claims 1 to 5.

Images