JP6835923B2 - Autonomous vacuum cleaner - Google Patents

Description

The present invention relates to an autonomous traveling vacuum cleaner.

Conventionally, an autonomous traveling type vacuum cleaner that cleans a room while moving autonomously is known. The autonomous traveling type vacuum cleaner is equipped with a rechargeable battery as a power source, and the control device controls the traveling motor that drives the wheel unit to perform autonomous traveling, while using a motor-driven rotating brush to scrape dust. Clean by sucking with a suction fan.
The autonomous driving type vacuum cleaner is automatically driven by a pair of left and right driving wheels.

Here, in order to automatically drive the autonomous traveling type vacuum cleaner, it is necessary to adjust the reduction ratio in a range of a certain value, for example, between 40 and 80, according to the torque of the motor that drives the wheels. That is, the torque for driving the wheels is 40 to 80 times the torque of the motor.

JP-A-2010-221964

By the way, there are the following two types of deceleration mechanisms for wheels of conventional autonomous vacuum cleaners.
For example, in one type, the deceleration structure of the wheel is a structure in which the deceleration structure of the wheel is decelerated from the motor via a gear to operate the wheel. At this time, since the gears are arranged in series in order to obtain a reduction ratio, the gears become longer in the front-rear direction with respect to the wheels. In this way, if the structure is such that ordinary spur gears are arranged in series, it is necessary to use a motor having a large torque and to have multiple gears even when the reduction ratio is small, and the wheel unit becomes large. Increasing the size of the wheel unit leads to an increase in the size of the main body, which makes it difficult to clean a narrow space, which is not desirable and needs to be reduced.

In the front-rear direction of the autonomous vacuum cleaner, a livestock battery that supplies power, a dust suction port, and a scraping brush that scrapes dust are arranged, so that they interfere with these components, so the wheel deceleration structure It is inconvenient that the wheel extends in the front-rear direction, which leads to an increase in the size of the autonomous traveling vacuum cleaner.

On the other hand, as for the motor, a commutator motor that needs to be long to obtain the torque to move the autonomous vacuum cleaner is used.
Therefore, a device for arranging gears and a configuration described in Patent Document 1 using a brushless motor of an outer rotor that has the same diameter as the commutator motor and can obtain a torque larger than that of the commutator motor have been proposed.

As another type, the configuration of the wheel reduction mechanism described in Patent Document 1 is arranged so that the diameter direction of the reduction mechanism fits inside the wheel.
In the case of this structure, since the outer diameter of the gear cannot be made large, the reduction ratio per step cannot be made large. Therefore, in order to obtain a large required reduction ratio, it is necessary to stack the gears vertically and arrange them in a plurality of stages, which increases the size in the thrust direction of the wheels.
Further, if the length of the reduction mechanism in the thrust direction is suppressed, the reduction ratio becomes small, so that it is necessary to increase the torque of the motor, which leads to an increase in cost such as raising the grade of the magnet.

The present invention has been devised in view of the above circumstances, and an object of the present invention is to provide an autonomous traveling type vacuum cleaner capable of miniaturizing a wheel unit.

In order to solve the above problems, the autonomous traveling type vacuum cleaner of the present invention includes a suction fan for generating a negative pressure, a suction port for sucking dust on the surface to be cleaned by the negative pressure of the suction fan, and the suction fan. In an autonomous traveling type vacuum cleaner provided with a dust collecting case for collecting dust arranged between the flow paths of the suction port and at least two wheels for autonomous traveling, the wheels rotate by input of a drive source. It is provided with a shaft that supports the load of the vehicle body and a reduction mechanism provided between the shaft and the wheels. The reduction mechanism is composed of a plurality of stages of reduction gears and is rotated by driving each traveling motor. Each reduction gear that is arranged in a region equal to or less than the outer diameter dimension of the drive wheels when viewed in the direction of the rotation axis of the drive wheels and constitutes the reduction mechanism within the region of the width dimension of the drive wheels when viewed in the front-rear direction. Part or all of the reduction gear is located, and the final reduction gear is decelerated by the reduction gear using the inscribed trochoid curve.

According to the present invention, it is possible to provide an autonomous traveling type vacuum cleaner capable of downsizing the wheel unit.

The perspective view of the autonomous traveling type vacuum cleaner which concerns on embodiment of this invention is seen from the left front. Bottom view of the autonomous vacuum cleaner. A cross-sectional view taken along the line AA of FIG. The perspective view which shows the internal structure which removed the case of the autonomous traveling type vacuum cleaner. Perspective view cut at BB in FIG. A perspective view of the wheel assembly of the first embodiment as viewed diagonally from above and behind. A side sectional view of the wheel assembly of the first embodiment. FIG. 7A is a sectional view taken along the line CC of FIG. 7A. An exploded perspective view of the wheel assembly. An exploded perspective view of the wheel assembly viewed from the opposite direction of FIG. An exploded perspective view of the planetary gear assembly. The schematic vertical cross-sectional view which shows the meshing state of the reduction mechanism between a drive wheel and a motor. A perspective view of the wheel assembly of the second embodiment as viewed diagonally from above and behind. An exploded perspective view of the wheel assembly of the second embodiment. An exploded perspective view of the wheel assembly viewed from the opposite direction of FIG. FIG. 12 is a sectional view taken along line DD of FIG. A cross-sectional view of the pinion gear and the cross section where the gear can be seen. FIG. 15 is a cross-sectional view taken along the line EE of FIG. FIG. 15 is a sectional view taken along line FF of FIG. (A) is a schematic vertical cross-sectional view showing the meshing state of the reduction mechanism between the drive wheel and the motor, and (b) is a principle diagram showing the bearings on both sides of the reduction mechanism and the camshaft and how the load is applied. A perspective view of the wheel assembly of the third embodiment as viewed diagonally from above and behind. A perspective view of the inside of the wheel assembly with the drive wheels of the third embodiment removed and viewed from above and rear in the opposite direction of FIG. The schematic vertical cross-sectional view which shows the meshing state of the reduction mechanism between a drive wheel and a motor. FIG. 3 is a vertical cross-sectional view showing an in-wheel motor drive device including the motor drive device of Patent Document 1.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings as appropriate.
FIG. 1 is a perspective view of an autonomous traveling vacuum cleaner according to an embodiment of the present invention as viewed from the front left. Of the directions in which the autonomous traveling type vacuum cleaner S advances, the side provided with the side brush 7 is forward, the vertically upward direction is upward, the drive wheels 2 and 3 are facing each other, and the drive wheel 2 side is left. The drive wheel 3 side is to the right. That is, as shown in FIG. 1 and the like, the front-back, up-down, and left-right directions are defined.
FIG. 2 is a bottom view of the autonomous traveling type vacuum cleaner.

The autonomous traveling type vacuum cleaner S is an electric device that automatically cleans a predetermined cleaning area (for example, the floor surface Y of a room) while autonomously moving.
The autonomous traveling type vacuum cleaner S includes a case 1 (1u, 1s) forming an outer shell, a pair of lower drive wheels 2, 3 (see FIG. 2), and training wheels 4. Further, the autonomous traveling type vacuum cleaner S is provided with a rotating brush 5, a guide brush 6 and a side brush 7 at the lower portion, and sensors 8 (8a, 8b, 8c) (see FIGS. 2, 3 and 4) around the autonomous traveling vacuum cleaner S. ing.

The drive wheels 2 and 3 are rotationally driven by the traveling motors 21 and 21A (see FIG. 6), respectively. The training wheels 4 are driven wheels and casters that rotate freely. The drive wheels 2 and 3 are provided on the center side in the front-rear direction and the outside in the left-right direction of the autonomous traveling vacuum cleaner S, and the auxiliary wheels 4 are provided on the front side in the front-rear direction and the center side in the left-right direction. ..
The side brush 7 is provided on the front side of the autonomous traveling type vacuum cleaner S and outside in the left-right direction, and as shown by the arrow α1 in FIG. 1, the area on the front outside of the autonomous traveling type vacuum cleaner S is outside in the left-right direction. It rotates so as to sweep inward from the floor, and collects dust on the floor surface toward the central rotating brush 5 (see FIG. 2). The two guide brushes 6 are provided on the inner side in the left-right direction with respect to the drive wheels 2 and 3, respectively, and are fixed to guide the dust collected by the side brush 7 so as not to escape from the width of the rotary brush 5 to the outside. It is a brush.
The rotary brush 5 is provided behind the drive wheels 2 and 3 of the autonomous traveling type vacuum cleaner S. The positions of the left and right end portions of the rotary brush 5 in the left-right direction can be inside the drive wheels 2 and 3, or inside the guide brush 6, respectively.

FIG. 3 is a cross-sectional view taken along the line AA of FIG.
FIG. 4 is a perspective view showing an internal configuration in which the case of the autonomous traveling vacuum cleaner is removed. Note that FIG. 4 shows a state in which the dust collecting case 12 is removed.
FIG. 5 is a perspective view showing a BB cross section of FIG.

As shown in FIG. 3, the autonomous traveling type vacuum cleaner S includes a rechargeable battery 9, a control device 10, a suction fan 11, and a dust collecting case 12 inside. The dust collecting case 12 has a suction port 12i formed above the rotating brush 5 as an inlet. A dust collecting filter 13 is attached to the outlet of the dust collecting case 12.

The rechargeable battery 9 is, for example, a secondary battery that can be reused by charging, and is housed in the battery housing unit 1s6 (see FIG. 2). The rechargeable battery 9 is arranged over the left and right ends of the autonomous traveling type vacuum cleaner S (see FIGS. 3 and 5).
The electric power from the rechargeable battery 9 is supplied to the sensor 8, each motor (21, 21A, 5m) such as a drive device, the control device 10, the suction fan 11, and the like.
The autonomous traveling type vacuum cleaner S is collectively controlled by the control device 10.

(Suction fan 11)
As shown in FIG. 4, the suction fan 11 is arranged near the center of the lower case 1s.
The air flow path by the suction fan 11 includes a dust collecting case 12, a dust collecting filter 13, a suction fan 11, and an exhaust port 1s5 (see FIG. 2) in this order from the suction port 14i (see FIG. 3) toward the downstream side. Is provided. The exhaust port 1s5 is provided in front of the rotary brush 5 and inside the drive wheels 2 and 3 in the left-right direction. By driving the suction fan 11 (see FIGS. 3 and 5), the air in the dust collecting case 12 is discharged to the outside from the exhaust port 1s5 to generate a negative pressure, and dust is discharged from the floor surface Y through the suction port 14i. Suck into the dust collection case 12.

A rotating brush 5 (see FIG. 2) for scraping dust on the floor surface is provided in the vicinity of the suction port 14i.
The suction fan 11 is installed between the suction fan 11 and the lower case 1s via an elastic body (not shown). By interposing an elastic body, the vibration of the suction fan 11 is attenuated and is not easily transmitted to the lower case 1s, so that vibration and noise can be reduced.

When the suction fan 11 and the rotary brush motor 5 m (see FIG. 4) are driven, the rotary brush 5 (see FIG. 3) scrapes dust from the floor surface and the like. The scraped dust is guided into the dust collecting case 12 through the suction port 14i and the suction port 12i. The air from which the dust has been removed by the dust collection filter 13 is discharged through the exhaust port 1s5 (see FIG. 2). The dust collecting case 12 can be attached and detached by opening the lid 1u1 (see FIG. 1) provided on the upper case 1u, and the dust collecting filter 13 is removed to dispose of the dust.

(Outline of operation of autonomous vacuum cleaner S)
Here, the rough operation of the autonomous traveling type vacuum cleaner S will be described.
The autonomous traveling type vacuum cleaner S is autonomously moved by the driving wheels 2 and 3 and the training wheels 4 (see FIG. 2), and can move forward, backward, turn left and right, turn super-credit, and the like. Then, the autonomous traveling type vacuum cleaner S collects dust with the side brush 7 and the guide brush 6 and collects the dust adhering around the rotating brush 5 through the suction port 14i by the suction force of the suction fan 11 to collect the dust. It is sucked into the dust collecting case 12 from the suction port 12i at the entrance of 12, and is retained in the dust collecting case 12 by the dust collecting filter 13 at the outlet.
When dust collects in the dust collecting case 12, the dust collecting case 12 is appropriately taken out from the main body Sh by the user, the dust collecting filter 13 is removed, and the dust is discarded.

Hereinafter, other configurations of the autonomous traveling type vacuum cleaner S will be described in detail.
(Case 1)
The case 1 is a housing that forms an outer shell and houses the traveling motors 21, 21A, the rotary brush motor 5 m, the suction fan 11, the dust collecting case 12, the control device 10, and the like.
The case 1 includes an upper case 1u forming an upper wall, a lower case 1s (see FIG. 2) forming a bottom wall (and a part of side walls), and a bumper 1b installed in the lower front part of the case 1. ..

The upper case 1u is provided with a lid 1u1 (see FIG. 1) for taking in and out the dust collecting case 12 (see FIG. 3).
As shown in FIG. 2, the lower case 1s is formed with a wheel unit accommodating portion 1s1, a side brush mounting portion 1s3, a hole portion 1s4, an exhaust port 1s5, and a battery accommodating portion 1s6.

The wheel unit accommodating portion 1s1 is formed on both the left and right sides of the center of the lower case 1s which has a substantially circular shape in the plan view of FIG.
The wheel unit accommodating portion 1s1 accommodates the wheel units 20 and 30 on which the drive wheels 2 and 3 are supported and driven.
A suction portion 14 is provided in the hole portion 1s4. A plurality of exhaust ports 1s5 are formed near the center of the lower case 1s and are sandwiched between the left and right wheel unit accommodating portions 1s1.

The battery accommodating portion 1s6 is formed on the front side of the center of the lower case 1s.
The rechargeable battery 9 is housed in the battery housing unit 1s6. Side brush mounting portions 1s3 for mounting the side brush 7 are formed on the left and right sides of the battery housing portion 1s6.
A hole 1s4 having a suction portion 14 (see FIG. 2) is formed on the rear side of the lower case 1s, that is, on the exhaust port 1s5 and the rear side of the wheel unit accommodating portion 1s1.

The bumper 1b (see FIGS. 1 and 2) is installed so as to be movable in the front-rear direction according to a force acting from the outside when colliding with an obstacle such as a wall. The bumper 1b is urged outward by a pair of left and right bumper springs (not shown).

When the acting force when colliding with an obstacle via the bumper 1b acts on the bumper spring, the bumper spring is deformed so as to collapse inward in a plan view, and the bumper 1b is retreated while urging the bumper 1b outward. Tolerate. When the bumper 1b separates from the obstacle and loses the above-mentioned acting force, the bumper 1b returns to the original position by the urging force of the bumper spring. Incidentally, the retreat of the bumper 1b (that is, contact with an obstacle) is detected by the bumper sensor 8a (see FIG. 4) described later, and the detection result is input to the control device 10.

(Suction unit 14)
The suction unit 14 shown in FIG. 3 forms a part of the air flow path containing dust sucked by the suction fan 11. The flow path downstream from the suction portion 14 communicates with the dust collection case 12, the dust collection filter 13, the suction fan 11, and the exhaust port 1s5 (see FIG. 2) in this order.
A rotary brush 5 for scraping dust is arranged in the suction portion 14, and a rotary brush motor 5 m (see FIG. 4) for driving the rotary brush 5 is fixed. The suction unit 14 is formed with a suction port 14i for sucking the dust scraped by the rotating brush 5 into the dust collecting case 12. The mouthpiece 14i is formed to have substantially the same length as the rotating brush 5 (see FIG. 2).
As shown in FIG. 3, the suction port 14i communicates with the suction port 12i of the opening of the dust collection case 12, and dust is collected in the dust collection case 12 via the suction port 14i and the suction port 12i.

In the suction portion 14, a rotary brush accommodating portion 14b for accommodating the rotary brush 5 is formed in the lower case 1s, and the rotary brush 5 described above is arranged in the rotary brush accommodating portion 14b. The rotary brush 5 is rotatably attached to the suction portion 14. The rotary brush 5 is removably attached to the suction portion 14.

(Dust collection case 12)
The dust collecting case 12 shown in FIG. 3 is a container that collects dust sucked from the floor surface Y through the suction port 14i formed in the suction portion 14. The dust collecting case 12 has substantially the same horizontal dimension as the rotating brush 5.
The dust collecting case 12 includes a main body for accommodating the collected dust, a lid for taking out the collected dust, and a foldable handle on the upper part of the main body. The main body of the dust collecting case 12 has a shape whose lower surface corresponds to the shape of the upper part of the suction portion 14, and has a suction port 12i having substantially the same opening shape facing the suction port 14i. The lid faces the suction port of the suction fan 11 and includes the dust collecting filter 13 described above.

(Sensor 8)
The bumper sensor 8a shown in FIG. 4 is a sensor that detects that the bumper 1b (see FIG. 1) has come into contact with an obstacle by retracting the bumper 1b, for example, a photocoupler. When an obstacle comes into contact with the bumper 1b, the sensor light is blocked by the retracting of the bumper 1b. A detection signal corresponding to this change is output to the control device 10.

The distance measuring sensor 8b shown in FIG. 4 is an infrared sensor that detects the distance to an obstacle. In the present embodiment, the distance measuring sensors 8b are provided at a total of three locations on the front surface and both side surfaces.
The distance measuring sensor 8b has a light emitting unit (not shown) that emits infrared rays and a light receiving unit (not shown) that receives reflected light that is reflected by an obstacle and returned. The distance to the obstacle is calculated based on the intensity of the reflected light detected by the light receiving unit. Of the bumper 1b, at least the vicinity of the distance measuring sensor 8b is made of resin or glass that transmits infrared rays.
Incidentally, other types of sensors (for example, ultrasonic sensor, visible light sensor) may be used as the distance measuring sensor 8b.

The floor surface distance measuring sensor 8c shown in FIG. 2 is an infrared sensor that measures the distance to the floor surface, and is installed at four locations on the lower surface of the lower case 1s, front, back, front, back, left, and right. By detecting a large step such as a staircase with the floor surface measuring sensor 8c, it is possible to prevent the autonomous traveling type vacuum cleaner S from falling. For example, when the floor distance measuring sensor 8c detects a step of about 30 mm or more in front, the control device 10 (see FIG. 3) controls the traveling motors 21 and 21A to retract the main body Sh and autonomously travel. The traveling direction of the mold vacuum cleaner S is changed.

(Control device 10)
The control device 10 shown in FIG. 3 is configured by mounting, for example, a microcomputer and peripheral circuits on a substrate. The microcomputer reads the control program stored in the ROM (Read Only Memory), expands it into the RAM (Random Access Memory), and executes it by the CPU (Central Processing Unit) to realize various processes. Peripheral circuits include A / D / D / A converters, drive circuits for various motors, sensor circuits, charging circuits for rechargeable batteries 9, and the like.

The control device 10 executes arithmetic processing according to the operation of the operation button bu by the user and the signal input from the sensor 8, and includes the motors (21, 21A, 5m), the sensor 8, the suction fan 11, and the like. Input and output signals.

(Training wheels 4)
The training wheels 4 shown in FIG. 2 are provided at the center in the front left-right direction of the lower case 1s. The training wheels 4 are wheels for smoothly moving the autonomous traveling type vacuum cleaner S by keeping the main body portion Sh at a predetermined height together with the drive wheels 2 and 3. The training wheels 4 are pivotally supported by the lower case 1s so that they rotate driven by the frictional force generated with the floor surface Y as the main body portion Sh moves, and further rotate 360 ° in the horizontal direction.

<< Embodiment 1 >>
Next, the wheel assemblies 20 and 30 including the drive wheels 2 and 3 of the autonomous traveling type vacuum cleaner S of the first embodiment will be described.
Since the wheel assembly 20 including the drive wheels 2 and the wheel assembly 30 including the drive wheels 3 can have the same configuration with respect to the left and right center surfaces of the autonomous traveling vacuum cleaner S, the wheel assembly 20 has the same configuration. Since the description of the configuration can be performed in the same manner as the wheel assembly 30, the description of the wheel assembly 30 will not be repeated.

FIG. 6 is a perspective view of the wheel assembly of the first embodiment as viewed from diagonally above and rearward, FIG. 7A is a side sectional view of the wheel assembly of the first embodiment, and FIG. 7B is a sectional view taken along the line CC of FIG. 7A. It is a figure.
FIG. 8 is an exploded perspective view of the wheel assembly, and FIG. 9 is an exploded perspective view of the wheel assembly viewed from the opposite direction of FIG. FIG. 10 is an exploded perspective view of the planetary gear assembly.

The deceleration mechanism between the drive wheels 2 and the motor 21 that drives the drive wheels 2 in the wheel assembly 20 of the first embodiment will be described.
Specifically, as shown in FIG. 7A, the motor 21 is arranged coaxially with the drive wheel 2, and as shown in FIG. 7B, the sun gear 22 is press-fitted into the drive shaft (input shaft) of the motor 21. It is fixed. The motor 21 is fixed to the motor bracket 21b.

As shown in FIG. 7B, three planetary gears 23 are provided in mesh with the teeth on the outer periphery of the sun gear 22.
The first outer gear 24 of the internal gear having internal teeth 24h that meshes with the outer teeth 23h of the three planetary gears 23 is fixed to a non-rotating portion such as the main body portion Sh illustrated in FIG.
Further, as shown in FIGS. 7A and 8, the second outer gear 25 of the internal gear having the internal teeth 25h is rotatably provided so as to mesh with the outer teeth of the three planetary gears 23. A drive wheel 2 (see FIG. 6) is fixed to the second outer gear 25 to form an output shaft.

The rotatable second outer gear 25 has the same reference circle diameter as the fixed first outer gear 24 by changing the number of teeth different from that of the fixed first outer gear 24 and changing the transition angle. .. In this way, the internal teeth 25h of the second outer gear 25 are arranged so as to mesh with the teeth 23h of the three planetary gears 23.
From the above, the reduction mechanism between the motor 21 and the drive wheels 2 includes a sun gear 22, three planetary gears 23, a first outer gear 24, and a second outer gear 25.

As shown in FIGS. 8 and 9, the second outer gear 25 is a bottomed cylindrical resin component having a short depth dimension. The second outer gear 25 has a disc-shaped bottom plate 25a and a cylindrical plate 25b having a shape that rises from the edge of the bottom plate 25a. Internal teeth 25h are formed on the inner peripheral surface side of the cylindrical plate 25b.

The bottom plate 25a of the second outer gear 25 is formed with a circular hole 25a0 in the center through which the motor shaft 21j escapes. Further, three bosses 25a1 (see FIG. 8) extending toward the motor 21 side are formed on the inner surface side of the bottom plate 25a of the second outer gear 25. A female screw 25a2 may be threaded on each boss 25a1 from the outer surface side to the inner surface side (paper surface in FIG. 8, from the left side to the right side) of the bottom plate 25a, but when the second outer gear 25 is formed of resin as described above. For example, by using a tapping screw, it can be fixed to the boss 25a1 without being screwed.

The drive wheel 2 has a disc-shaped bottom plate 2s and a cylindrical wheel portion 2w rising from an edge portion of the bottom plate 2s. The drive wheel 2 is formed by, for example, an elastomer. The drive wheel 2 may be formed of a material other than the elastomer. The outer diameter dimension s1 (see FIG. 7A) of the wheel portion 2w of the drive wheel 2 is a dimension of about 50 mm to about 80 mm. The outer diameter dimension s1 of the wheel portion 2w may be provided so as to have a maximum of about 80 mm and the minimum outer diameter dimension s1 of about 50 mm.

The wheel portion 2w is a portion that comes into contact with the floor surface Y during traveling, and the inside of the wheel portion 2w in the left-right direction is a cylindrical surface 2w1 in a state of being attached to the autonomous traveling type vacuum cleaner S. On the other hand, on the lateral side of the wheel portion 2w in the left-right direction, a cylindrical concavo-convex cylindrical surface 2w2 having a concave shape 2w and a convex shape 2wt is formed.
As shown in FIG. 8, the disc-shaped bottom plate 2s is formed with three bosses 2s1 for fixing the second outer gear 25 inside. Each boss 2s1 is provided with a hole 2s2 through which a screw n1 for fixing the second outer gear 25 is inserted.

The assembly of the drive wheel 2 and the second outer gear 25 is performed as follows. The second outer that outputs the drive wheel 2 by inserting the screw n1 into the hole 2s2 formed in the disk-shaped bottom plate 2s of the drive wheel 2 and screwing it into the female screw 25a2 of the second outer gear 25. It is fixed to the gear 25.

With the above configuration, the three planetary gears 23 rotate by meshing with the internal teeth 24h of the fixed first outer gear 24 and the internal teeth 25h of the rotatable second outer gear 25, respectively. While the three planetary gears 23 move the internal teeth 24h of the fixed first outer gear 24 by one rotation, the rotatable second outer gear 25 rotates by a number of teeth different from that of the first outer gear 24. It becomes.

FIG. 11 shows the meshed state of the speed reduction mechanism between the drive wheels 2 and the motor 21 that drives the drive wheels 2. FIG. 11 is a schematic vertical cross-sectional view showing the meshed state of the reduction mechanism between the drive wheels and the motor.
Assuming that the number of teeth of the sun gear 22 is z1, the number of teeth of the planetary gear 23 is z2, the number of teeth of the fixed first outer gear 24 is z3, and the number of teeth of the rotatable second outer gear 25 is z4, the drive is driven from the input motor 21. The reduction ratio N up to the second outer gear 25 of the output to which the wheel 2 is fixed is obtained as follows.
Here, assuming that the number of planetary gears 23 is n and m is a natural number of 1, 2, 3, ....., the number of teeth z1 of the sun gear 22 has the number of teeth equal to the number of planetary gears 23. It is expressed by the following equation (1).
z1 = n × m (1)

Further, as for the number of teeth z3 of the fixed first outer gear 24, assuming that m is a natural number of 1, 2, 3, ....., the fixed first outer gear 24 has the number of teeth corresponding to the number of planetary gears 23. Therefore, if m is a natural number of 1, 2, 3, ...., it is expressed by the following equation (2).
z3 = n × m (2)
The number of teeth z4 of the rotatable second outer gear 25 is given by the following equation (3).
z4 = z3 + (n × m) (3)

Since the planetary gear 23 only mediates between the sun gear 22, the first outer gear 24, and the second outer gear 25,
The reduction ratio N1 is represented by the following equation (4).
N1 = z4 × (z3 + z1) ÷ (z1 × (z4-z3)) (4)

For example, if z1 = 57, z2 = 15, z3 = 84, and z4 = 87, the reduction ratio N1 is 71.7.
In this way, the reduction ratio N1 = about 40 to about 80 can be realized by configuring the wheel assembly 20.

As shown in FIG. 7A, the wheels 2 are arranged on the outer periphery of the fixed first outer gear 24 and the rotatable second outer gear 25. As a result, the mysterious planetary gear reduction mechanism can be arranged inside the wheel 2. Similarly, the mysterious planetary gear reduction mechanism can be arranged inside the wheel 3.
Therefore, the reduction mechanism of the drive wheels 2 and 3 can be miniaturized in both the thrust direction (axial direction) and the diameter direction of the drive wheels 2 and 3.

<Cushioning mechanism K>
When external force received from the ground by the drive wheels 2 and 3 is applied to the gears (22, 23, 24, 25), backlash and the like may change, causing problems such as increased noise and energy transmission loss. is there.
Therefore, as shown in FIGS. 7A and 7B, a shock absorber K is provided between the drive wheel 2 and the housing 26.

The housing 26 is provided between the drive wheel 2 and the rotatable second outer gear 25 to which the drive wheel is fixed.
The shock absorber K is composed of a pin 26p supported by the housing 26 and a cylindrical roller 26r rotatably inserted into the pin 26p.
As shown in FIGS. 8 and 9, the housing 26 is a bottomed cylindrical resin component having a shallow depth. The housing 26 has a disc-shaped bottom plate 26a, a cylindrical side plate 26b, and a flange plate 26c.

The bottom plate 26a is formed with a central hole 26a1 in the center through which the three bosses 25a1 of the drive wheels 2 are inserted.
A pin 26p made of stainless steel or the like is fixed to the flange plate 26c in the axial direction of the drive wheel 2. A roller 26r is rotatably inserted through the pin 26p. For the roller 27r, for example, a resin such as POM (Polyoxymethylene, Polyacetal) is used. The roller 26r is arranged at the position shown in FIG. 7A, the pin 26p is passed through the roller 26r, and then the pin 26p is fixed to the flange plate 26c and the cylindrical side plate 26b by press fitting or the like. As a result, the roller 26r is rotatably provided on the pin 26p.

With the above configuration, by narrowing the clearance between the inner peripheral surface 2n of the drive wheel 2 (see FIG. 7A) and the roller 27r, the impact and external force received by the drive wheel 2 from the floor surface Y are transmitted to the housing 26 via the roller 26r. You can receive it at. As a result, it is possible to suppress the impact and external force received by the drive wheel 2 from the floor surface Y from being transmitted to gears such as the planetary gear 23 and the sun gear 22.

According to the configuration of the first embodiment, the following effects are exhibited.
1. 1. The reduction ratio N1 = about 40 required for the autonomous traveling vacuum cleaner S while keeping the reduction mechanisms of the drive wheels 2 and 3 including the motor 21 within the outer diameter dimension s1 and the width dimension s2 of the drive wheels 2 and 3, respectively. ~ Approximately 80, preferably 70-80 can be achieved.

2. 2. As shown in FIGS. 6, 7A and 7B, when viewed in each axle direction of the drive wheels 2 and 3, the reduction mechanisms (22, 23, 24, 25) of the drive wheels 2 and 3 including the motor 21 are Each of the drive wheels 2 and 3 can be housed in the region of each outer diameter dimension s1. Therefore, the rechargeable battery 9, the dust collecting case 12, the suction port 14i, and the rotating brush 5 can be arranged at arbitrary positions in the region in the front-rear direction excluding the drive wheels 2 and 3. Therefore, the autonomous traveling type vacuum cleaner S can be miniaturized. Further, since the rechargeable battery 9, the dust collecting case 12, the suction port 14i, and the rotating brush 5 can be arranged in the left-right direction excluding the areas of the drive wheels 2 and 3, the basic function of the autonomous traveling type vacuum cleaner S can be improved. ..

3. 3. When the autonomous traveling type vacuum cleaner S is viewed in the front-rear direction (see FIGS. 1 and 4), as shown in FIG. 7A, the motor 21 and the gears of the reduction mechanism (each gear of the reduction mechanism) are within the width dimensions s2 of the drive wheels 2 and 3. Some or all of 22, 23, 24, 25) can be accommodated.
From the above, the reduction mechanism of the drive wheels 2 and 3 can be miniaturized. That is, it is possible to reduce the size of the reduction mechanism of the drive wheels 2 and 3 while keeping the reduction ratio N1 large.

4. In this reduction mechanism, a large external force due to torque is applied to the planetary gear 23, the first outer gear 24, and the second outer gear 25, and a large stress is generated. However, since this reduction mechanism uses three planetary gears 23, the external force is 1/3 and the generated stress is also 1/3. Further, the external force applied to the first outer gear 24 and the second outer gear 25 is also transmitted through the three planetary gears 23, so that each is reduced to 1/3. Therefore, the stress generated in each of the first outer gear 24 and the second outer gear 25 is reduced to 1/3.
Therefore, in this deceleration mechanism, the generated stress is reduced and the mechanical reliability is high.

5. A buffer mechanism K for narrowing the clearance between the drive wheels 2 and the roller 26r supported by the housing 26 is provided between each of the drive wheels 2 and 3 and the housing 26. Therefore, the housing 26 can receive the impact and the external force applied to the drive wheels 2 and 3. Therefore, the impact and external force applied to the drive wheels 2 and 3 are suppressed from being transmitted to the gears (22, 23, 24, 25) of the reduction mechanism.
Therefore, the deceleration mechanism (22, 23, 24, 25) is highly reliable and can have a long life.

6. From the above, it is possible to realize an autonomous traveling type vacuum cleaner S which is compact, can generate high output torque, and has a reduction mechanism having high mechanical reliability in which generated stress is reduced.
In the first embodiment, the case where three planetary gears 23 are used has been illustrated, but if the number of planetary gears 23 is a plurality, the number can be appropriately selected.

<< Embodiment 2 >>
Next, the wheel assemblies 20A and 30A including the drive wheels 2 and 3 of the autonomous traveling type vacuum cleaner S of the second embodiment will be described.
Since the wheel assembly 20A including the drive wheels 2 and the wheel assembly 30A including the drive wheels 3 can have the same configuration with respect to the left and right center surfaces of the autonomous traveling vacuum cleaner S, the wheel assembly 20A has the same configuration. Since the description of the configuration can be the same as the description of the wheel assembly 30A, the description of the wheel assembly 30A will not be repeated.

FIG. 12 is a perspective view of the wheel assembly of the second embodiment as viewed from diagonally above and rearward.
FIG. 13 is an exploded perspective view of the wheel assembly of the second embodiment, and FIG. 14 is an exploded perspective view of the wheel assembly viewed from the opposite direction of FIG.
15 is a cross-sectional view taken along the line DD of FIG. 12, and FIG. 16 is a cross-sectional view cut along a cross section in which the pinion gear and the gear can be seen.

A planetary gear reduction mechanism using a trochoid curve is adopted as a reduction mechanism between the drive wheels 2 and the motor 31 in the wheel assembly 20A.
As shown in FIG. 16, a motor 31 (rotating shaft 31j) is provided so as to be eccentric to the rotating shaft (position of the camshaft 34) of the drive wheel 2.

A pinion gear 32 is fixed to the rotating shaft 31j of the motor 31.
As shown in FIG. 12, the motor 31 is fixed to the first housing ha. The first housing ha is fixed to the second housing hb that forms a structural member of the drive wheel 2.
Specifically, as shown in FIG. 13, a screw insertion hole ha1 is formed in the first housing ha, while a female screw hb1 is threaded in the second housing hb. The first housing ha is fixed to the second housing hb by inserting a screw (not shown) through the screw insertion hole ha1 of the first housing ha and screwing it into the female screw hb1 of the second housing hb.
Further, the gear 33 is provided with a larger number of teeth than the pinion gear 32 by meshing with the pinion gear 32 (see FIG. 16).

Here, with the aim of reducing noise, helical gears are used for the pinion gear 32 and the gear 33 of the first gear.
A camshaft 34 (see FIGS. 13, 14, etc.) is fixed to the rotating shaft of the gear 33.
As a result, the output of the motor 31 is decelerated and transmitted to the camshaft 34 via the pinion gear 32 and the gear 33.

As shown in FIGS. 13 and 14, the camshaft 34 has a first central shaft 34a, a first cam portion 34b, a second cam portion 34c, and a second central shaft 34d.
The first central shaft 34a of the camshaft 34 is coaxial with the rotation shaft of the drive wheel 2, and is formed on the central shaft of the gear 33 with a rectangular cross section of a detent. The first central shaft 34a is fitted and fixed to the central shaft of the gear 33.

The first cam portion 34b is a cylindrical shaft eccentric to the first central shaft 34a.
The second cam portion 34c is a cylindrical shaft formed so as to be eccentric to the first central shaft 34a and to be out of phase with the first cam portion 34b about the first central shaft 34a by about 180 degrees. ..
Like the first central shaft 34a, the second central shaft 34d is a cylindrical shaft coaxial with the rotation shaft of the drive wheel 2. The second central shaft 34d is rotatably supported by a bearing 38t inserted through the central shaft of the drive wheel 2.

Therefore, the camshaft 34 rotates coaxially with the rotation axis of the drive wheel 2. However, as will be described later, the rotation of the drive wheel 2 and the rotation of the camshaft 34 are independent.
A planetary gear 35 on which teeth 35h are formed using a trochoidal curve is arranged on the first cam portion 34b of the camshaft 34 via a bearing 34t1.

The planetary gear 35 is formed with a plurality of columnar recesses 35a for coaxially rotating the rotating plate 38. The columnar recess 35a is a recess having a cylindrical space that does not penetrate the motor 31 side.
A drive wheel 2 is fixed to the rotating plate 38. By rotationally driving the rotary plate 38, the drive wheels 2 are rotationally driven.
As shown in FIG. 15, the rotating plate 38 is built in the bearing 39 (see FIGS. 13 and 14). The bearing 39 may be a sliding bearing or a ball bearing. On the other hand, the rotating plate 38 is connected to the camshaft 34 via a bearing 38t.
A planetary gear 36 on which teeth 36h are formed using a trochoidal curve is arranged on the second cam portion 34c of the camshaft 34 via a bearing 34t2. The planetary gear 35 and the planetary gear 36 are gears having the same shape, and are attached to the first cam portion 34b and the second cam portion 34c with their phases shifted by 180 degrees by axially supporting them.

The cams of the planetary gears 35 and 36 are shifted by 180 degrees, and two of them are arranged to reduce vibration. In other words, by eccentricizing the planetary gear 36 in the direction opposite to that of the planetary gear 35, it is possible to cancel the motion due to the eccentricity of the planetary gear 35 and suppress vibration, noise and the like.

The planetary gear 36 is provided with a plurality of insertion holes 36a for coaxially rotating the rotating plate 38. The insertion holes 36a of the planetary gear 36 are formed at the same intervals as the columnar recesses 35a of the planetary gear 35.

FIG. 17 is a cross-sectional view taken along the line EE of FIG. FIG. 18 is a cross-sectional view taken along the line FF of FIG.
The teeth 35h and 36h of the planetary gears 35 and 36 mesh with the teeth 37h of the outer gear 37, respectively. The outer gear 37 is a fixed gear.
Since the teeth 35h and 36h of the planetary gears 35 and 36 are formed by using a trochoid curve, the outer gear 37 that meshes with the teeth 35h and 36h is formed by the cylindrical teeth 37h. If ordinary involute gears are used as planetary gears 35 and 36, involute interference occurs. Therefore, the trochoidal curved teeth 35h and 36h and the cylindrical teeth 37h are formed.

The cylindrical tooth 37h is formed by a roller 37h2 rotatably supported by a pin 37h1.
As shown in FIG. 18, a roller 38r rotatably supported by a pin 38p fixed to a rotating plate 38 is loosely fitted in a columnar recess 35a of the planetary gear 35 and an insertion hole 36a of the planetary gear 36. There is.

As shown in FIGS. 13 and 14, the rotating plate 38 is an annular part, and is rotatably supported by a second central shaft 34d of the camshaft 34 via a bearing 38t.
According to the above configuration, when the planetary gears 35 and 36 rotate due to meshing with the cylindrical teeth 37h of the outer gear 37, the rotating plate 38 passes through the cylindrical recess 35a and the roller 38r penetrating the insertion hole 36a. Will rotate around the second central axis 34d of the camshaft 34.

As shown in FIG. 14, the rotating plate 38 is threaded with three female threads 38n.
The drive wheel 2 is fixed to the rotary plate 38 by inserting a screw n2 into each of the three through holes 2s4 penetrating the drive wheel 2 and screwing the screw n2 into the female screw 38n of the rotary plate 38.

The drive wheel 2 has a disc-shaped bottom plate 2s and a cylindrical wheel portion 2w. The drive wheel 2 is formed by, for example, an elastomer. The drive wheel 2 may be formed of a material other than the elastomer. The outer diameter dimension s3 of the wheel portion 2w of the drive wheel 2 is a dimension of about 50 mm to about 80 mm. That is, the outer diameter dimension s3 (see FIG. 17) of the wheel portion 2w is set to a maximum of about 80 mm, and the minimum outer diameter dimension is set to about 50 mm.

The wheel portion 2w is a portion that comes into contact with the floor surface during traveling, and the inside is a cylindrical surface 2w1. On the other hand, on the outside of the drive wheel 2, a cylindrical concave-convex cylindrical surface 2w2 having a concave shape 2w and a convex shape 2wt is formed.
As shown in FIG. 14, the above-mentioned three through holes 2s4 are formed in the disk-shaped bottom plate 2s.

With the above configuration, when the camshaft 34 rotates, the planetary gears 35 and 36 revolve around each operation of the first cam portion 34b and the second cam portion 34c of the camshaft 34 (each axis of the planetary gears 35 and 36). (While the portion is rotating), the outer gear 37 rotates by meshing with the teeth 37h of the teeth 35h and 36h, respectively.

That is, the difference between the number of teeth 37h of the fixed outer gear 37 and the number of teeth 35h (35h) of the planetary gear 35 (36) can be taken out as the rotation of the planetary gear 35.
Specifically, the structure is such that the rotation speed of the planetary gears 35 and 36 is taken out by using the rotating plate 38 via the roller 38r penetrating the columnar recess 35a and the insertion hole 36a.

The meshing state of the speed reduction mechanism between the drive wheels 2 and the motor 31 is as shown in FIG. 19A. Note that FIG. 19A is a schematic vertical cross-sectional view showing the meshing state of the reduction mechanism between the drive wheels and the motor, and FIG. 19B shows the bearings and loads on both sides of the reduction mechanism and the camshaft. It is a principle diagram which shows how to apply.
Here, assuming that the number of teeth of the pinion gear 32 is z1, the number of teeth of the gear 33 is z2, the number of teeth of the planetary gears 35 and 36 is z3, and the number of teeth of the outer gear is z4, the reduction ratio N2 is calculated by the following equation (5). It is represented by.
N2 = (z2 ÷ z1) × (1 ÷ ((z4-z3) ÷ z3)) (5)

For example, if the number of teeth of the pinion gear 32 is z1 = 12, the number of teeth of the gear 33 is z2 = 48, the number of teeth of the planetary gears 35 and 36 is z3 = 17, and the number of teeth of the outer gear 37 is z4 = 18, the reduction ratio N2 = 68.0. With the above configuration, the reduction ratio N2 can be set to about 40 to about 80.

In this case, the reduction ratio N2A of the rotating plate 38 in which the rotation of the camshaft 34 is transmitted via the planetary gears 35 and 36 with respect to the rotation of the camshaft 34 (z2 = 48) is given by the following equation.
Reduction ratio N2A = 1 ÷ ((z4-z3) ÷ z3)
That is, the rotation speed of the camshaft 34, which is a shaft, and the rotation speed of the drive wheel 2 (rotary plate 38) are different.

As shown in FIG. 17, when the camshaft 34 rotates in the direction of arrow γ1, the planetary gear 35 fixed to the camshaft 34 rotates in the same direction (direction of arrow γ1). Since the number of teeth of the planetary gear 35 is z3 = 17 and the number of teeth of the outer gear 37 is smaller than z4 = 18, the planetary gear 35 is in the direction of arrow γ2 opposite to the rotation direction of the camshaft 34 (arrow γ1). It will rotate.

According to the configuration of the second embodiment, the following effects are exhibited.
1. 1. A high reduction ratio (for example, a reduction ratio N of about 40 to about 80, preferably 65 to 80) can be obtained only by two-stage deceleration of the gear 33 and the planetary gear 35 and the planetary gear 35 and the outer gear 37. .. Therefore, it is possible to arrange the highly efficient deceleration mechanism inside the drive wheels 2 and 3.

2. 2. As shown in FIGS. 16 to 18, when viewed in each axle direction of the drive wheels 2 and 3, the reduction mechanisms (32, 33, 34, 35) of the drive wheels 2 and 3 including the motor 31 are driven wheels, respectively. It can be accommodated within each of the outer diameter dimensions s3 (see FIG. 17) of 2 and 3. Therefore, the rechargeable battery 9, the dust collecting case 12, the suction port 14i, and the rotating brush 5 can be arranged at arbitrary positions in the front-rear direction except for the drive wheels 2 and 3 of the autonomous traveling type vacuum cleaner S. Therefore, the autonomous traveling type vacuum cleaner S can be miniaturized. Further, since the rechargeable battery 9, the dust collecting case 12, the suction port 14i, and the rotating brush 5 can be arranged in the left-right direction excluding the areas of the drive wheels 2 and 3, the basic function of the autonomous traveling vacuum cleaner S is improved. it can.

3. 3. When the autonomous traveling type vacuum cleaner S is viewed in the front-rear direction (see FIGS. 1 and 4), as shown in FIG. 12, each of the motor 31 and the reduction mechanism is within the region of each width dimension s4 of the drive wheels 2 and 3. It can accommodate some or all of the gears (32, 33, 34, 35, 37).

4. Since the teeth 35h and 36h of the planetary gears 35 and 36 are formed by using trochoid curves, respectively, stress concentration can be suppressed and stress resistance is strong.

5. Since the structure is such that the gears 33 and the planetary gears 35 and 36 of the rotating parts are supported at both ends, the structure is strong against external force.

6. Since the planetary gears 35 and 36 fixed to the camshaft 34 and out of phase by 180 degrees are used, vibration can be suppressed.

7. Although an impact or an external force is applied to the drive wheels 2 and 3 from the floor surface Y, each rotating plate 38 to which the drive wheels 2 and 3 are fixed is free from the cylindrical recesses 35a and the insertion holes 36a of the planetary gears 35 and 36. It is connected to the planetary gears 35 and 36 via the fitted roller 38r. Further, since the drive wheels 2 and 3 are rotating plates 38 and the like and receive impacts and external forces, it is possible to prevent the impacts and external forces applied to the drive wheels 2 and 3 from being transmitted to the gear portions (32, 33, 34, 35, 37). Will be done.

8. In the wheel assembly 20A of the second embodiment, as shown in FIG. 19B, the load applied to the drive wheels 2 (3) when the autonomous traveling type vacuum cleaner S is traveling is a cam via the rotating plate 38 and the bearing 38t. It is transmitted to the shaft 34. The load W transmitted to the camshaft 34 is transmitted to the first housing ha and the second housing hb (see FIG. 15) via the bearings 34t1 and 38t, respectively. Therefore, the speed reduction mechanism provided between the drive wheels 2 and the motor 31 does not have to receive the load W. Therefore, the reliability and durability of the reduction mechanism are high.

On the other hand, in Patent Document 1, as shown in FIG. 23, the wheel hub (32) to which the drive wheels are fixed is supported by the wheel hub bearing (33). FIG. 23 is a vertical cross-sectional view (FIG. 1 of Patent Document 1) showing an in-wheel motor drive device including the motor drive device of Patent Document 1.
Further, the wheel-side rotating member (28) to which the wheel hub (32) is fixed is supported by the outer ring of the bearing (64). The inner ring of the bearing (64) is supported at one end of the damping portion input shaft (25). The other portion of the damping portion input shaft (25) is rotatably supported by the pump casing (22p) via a rolling bearing (62). Therefore, the load applied to the drive wheels is pumped not only through the wheel hub bearing (33) but also through the wheel side rotating member (28), the bearing (64), the damping part input shaft (25), the rolling bearing (62), and the like. The casing (22p) is receiving. Therefore, the load applied to the drive wheels is received by the mechanism unit, and the reliability of the mechanism unit is lower than that of the second embodiment (invention of the present application).

9. As shown in FIG. 15, the camshaft 34 is supported by the first bearing 34t1 and the second bearing 38t. Then, the rotating plate 38 is supported by the second housing hb via the third bearing 39.
A first bearing 38t in which the camshaft 34 is supported and arranged between the camshaft 34 and the drive wheel 2 of the wheel, and a second bearing in which the camshaft 34 is supported and arranged on the center side of the first bearing 38t. By providing the bearing 34t1 of the above, the mechanism for driving the drive wheel 2 can be miniaturized.

The diameter dimension 39s of the inner peripheral surface of the third bearing 39 is larger than either one of the diameter dimension 38t1 of the outer peripheral surface of the first bearing 38t and the diameter dimension 34s of the outer peripheral surface of the second bearing 34t1, and the one bearing It is placed overlapping with. In the example shown in FIG. 15, the diameter dimension 39s of the inner peripheral surface of the third bearing 39 is larger than the diameter dimension 38t1 of the outer peripheral surface of the first bearing 38t, and the third bearing 39 overlaps the first bearing 38t. Be placed. The diameter dimension 39s of the inner peripheral surface of the third bearing 39 is larger than either the diameter dimension 38t1 of the outer peripheral surface of the first bearing 38t and the diameter dimension 34s of the outer peripheral surface of the second bearing 34t1. Bearing 39 can be placed on top of the first bearing 34t1 or the second bearing 38t.

Conventionally, the wheel fixed to the shaft rotates, or the wheel is rotatably supported by the fixed shaft via a bearing, and the wheel rotates independently of the shaft.
On the other hand, in the second embodiment (the present invention), the camshaft 34 of the shaft and the drive wheel 2 (rotating plate 38) rotate independently.
From the above, the reduction mechanism of the drive wheels 2 (3) can be made compact.

On the other hand, in Patent Document 1, as shown in FIG. 1 of Patent Document 1, an external force is received by the bearing portion casing (22c) on the outer side of the housing via the bearing (64), so that the deceleration mechanism inputs the deceleration portion. The configuration increases in the direction of the shaft (25) and the rotation shaft (35).

10. From the above, it is possible to realize an autonomous traveling type vacuum cleaner S which is compact, can generate high output torque, and has a reduction mechanism having high mechanical reliability in which generated stress is reduced.

In the second embodiment, the case where two planetary gears 35 and 36 are used has been described, but the number of planetary gears may be singular.

Further, the configuration in which the rotation of the planetary gears 35 and 36 is transmitted to the drive wheels 2 and 3 via the rotating plate 38 has been described. However, if the rotation of the planetary gears 35 and 36 can be transmitted to the drive wheels 2 and 3, respectively. The driving force may be directly transmitted from the planetary gears 35 and 36 to the driving wheels 2 and 3, respectively. Alternatively, a configuration other than the rotating plate 38 may be used to transmit the rotation of the planetary gears 35 and 36 to the rotating plate 38.

<< Embodiment 3 >>
Next, the wheel assemblies 20B and 30B including the drive wheels 2 and 3 of the autonomous traveling type vacuum cleaner S of the third embodiment will be described.
The wheel assemblies 20B and 30B of the third embodiment have a reduction mechanism using a worm gear and a spur gear.
Since the wheel assembly 20B including the drive wheels 2 and the wheel assembly 30B including the drive wheels 3 are plane-symmetrical with respect to the left and right central surfaces of the autonomous traveling type vacuum cleaner S, the wheel assembly 20B can be configured in the same manner. Since the description of the configuration of the above can be performed in the same manner for the wheel assembly 30B, the description of the wheel assembly 30B will not be repeated.

FIG. 20 is a perspective view of the wheel assembly of the third embodiment as viewed from diagonally above and rearward.
FIG. 21 is a perspective view of the inside of the wheel assembly from the upper rear in the opposite direction of FIG. 20 with the drive wheels of the third embodiment removed.

In the wheel assembly 20B of the third embodiment, the motor 41 is arranged at a position deviated (eccentric) from the rotation axis (rotation center) of the drive wheel 2. As shown in FIG. 21, a first worm gear 42 is fixed to the drive shaft 41j of the motor 41. Further, the first worm wheel 43 that receives the rotation of the first worm gear 42 is fixed to one side of the shaft 44.
A second worm gear 45 is fixed to the other side of the shaft 44.

A second worm wheel 46 is provided in mesh with the second worm gear 45 of the shaft 44.
A first spur gear 47 is provided coaxially with the second worm wheel 46.
The teeth 48h of the second spur gear 48 provided coaxially with the drive wheel 2 mesh with the first spur gear 47. A drive wheel 2 (see FIG. 20) is fixed to the second spur gear 48.
As a result, the rotation of the motor 41 is transmitted to the first worm wheel 43 via the first worm gear 42.

The rotation of the first worm wheel 43 is transmitted to the second worm gear 45 provided on the opposite side of the first worm wheel 43 via the shaft 44.
The second worm gear 45 transmits rotation to the second worm wheel 46, and is provided coaxially with the drive wheel 2 via a first spur gear 47 fixed coaxially with the second worm wheel 46. The rotation is transmitted to the spur gear 48 of 2. Since the drive wheels 2 are fixed coaxially with the second spur gear 48, the rotation of the motor 41 is transmitted to the drive wheels 2.

The shaft 48j (see FIG. 21) of the second spur gear 48 is rotatably supported by a bearing fixed to a housing (not shown). As a result, the load applied to the drive wheels 2 is transmitted to the housing and is not applied to the speed reduction mechanism provided between the motor 41 and the drive wheels 2, so that wear of the speed reduction mechanism is suppressed and reliability is high.
A shaft (not shown) of the drive wheel 2 is provided separately from the spur gear 48, and the shaft is rotatably supported by a bearing fixed to the housing, and the vibration of the drive wheel 2 is transmitted to the spur gear 48. It may be configured so that it is not transmitted.

Since the configurations of the drive wheels 2 and 3 are almost the same as those of the first and second embodiments, they are shown with the same reference numerals, and detailed description thereof will be omitted. The outer diameter dimension s5 (see FIG. 20) of the wheel portion 2w of the drive wheel 2 is about 50 mm to about 80 mm.
The meshing state of the speed reduction mechanism between the drive wheels 2 and the motor 41 is as shown in FIG. Note that FIG. 22 is a schematic vertical cross-sectional view showing the meshed state of the reduction mechanism between the drive wheels and the motor.

Here, the number of teeth of the first worm gear 42 is z1, the number of teeth of the first worm wheel 43 is z2, the number of teeth of the second worm gear 45 is z3, the number of teeth of the second worm wheel 46 is z4, and the second Assuming that the number of teeth of the spur gear 47 of 1 is z5 and the number of teeth of the second spur gear 48 is z6, the reduction ratio N3 is expressed by the following equation (6).
N3 = (z2 ÷ z1) × (z4 ÷ z3) × (z6 ÷ z5) (6)

By configuring the wheels assembly 20B and 30B, it is possible to realize a reduction ratio N3 = about 40 to about 80, respectively.
By using the worm gears (42, 45), high deceleration is possible while the turning radius is small, which is advantageous in terms of noise and vibration. Further, since the worm gears (42, 45) are small, the size can be reduced, and the reduction mechanism can be completed inside the drive wheels 2 and 3.

According to the configuration of the third embodiment, the following effects are exhibited.
1. 1. By using two worm gears, a first worm gear 42 and a second worm gear 45, a reduction ratio can be obtained.

2. By using two worm gears and changing the rotation direction twice, it is possible to reduce the size of the reduction mechanism of the drive wheels 2 and 3.

3. 3. Therefore, as shown in FIGS. 20 and 21, when viewed in each axle direction of the drive wheels 2 and 3, the reduction mechanisms of the drive wheels 2 and 3 including the motors 41 and 41A (42, 43, 44, 45, 46, 47, 48) can be housed within the regions of the outer diameter dimensions s5 (see FIG. 20) of the drive wheels 2 and 3, respectively. Therefore, the rechargeable battery 9, the dust collecting case 12, the suction port 14i, and the rotating brush 5 can be arranged at arbitrary positions in the front-rear direction except for the drive wheels 2 and 3 of the autonomous traveling type vacuum cleaner S. Therefore, the autonomous traveling type vacuum cleaner S can be miniaturized. Further, since the rechargeable battery 9, the dust collecting case 12, the suction port 14i, and the rotating brush 5 can be arranged in the left-right direction excluding the areas of the drive wheels 2 and 3, the basic function of the autonomous traveling type vacuum cleaner S can be improved. ..

4. When the autonomous traveling type vacuum cleaner S is viewed in the front-rear direction (see FIGS. 1 and 4), as shown in FIG. 20, the motors 41, 41A and the reduction mechanism are within the width dimensions s6 of the drive wheels 2 and 3. It can accommodate some or all of the gears (22, 23, 24, 25).

5. By using two worm gears, the first worm gear 42 and the second worm gear 45, the reduction ratio can be increased and the stress generation in the gear can be suppressed. Therefore, the number of teeth 48h of the second spur gear 48 and the number of teeth 47h of the first spur gear 47 can be increased.
As described above, conventionally, there has been a demand for using fine teeth for the gear of the reduction mechanism, but since the reduction ratio becomes large, it is necessary to increase the tooth width. Therefore, there is a problem that the reduction mechanism becomes large when the teeth are made large so as to withstand the torque.
According to the present invention, this problem has been solved.

6. From the above, it is possible to realize an autonomous traveling type vacuum cleaner S having a small size, high output torque, a reduction mechanism with high mechanical reliability in which generated stress is reduced, and a reduction mechanism.
The present invention is not limited to the configurations of the first to third embodiments, and various modified forms and specific forms are possible within the scope of the appended claims.

2 or 3 drive wheels (wheels)
31 motor (traveling motor, drive source)
11 Suction fan 12 Dust collection case 14i Suction port 33 Gears (reduction gear, reduction mechanism)
34 Camshaft (shaft)
35 Planetary gears (reduction gears, planetary gears, reduction mechanism)
36 Planetary gears (reduction gears, planetary gears, reduction mechanism)
37 Outer gear (reduction gear, reduction mechanism)
38 Rotating plate (reduction gear, reduction mechanism, final reduction gear)
s3 Outer diameter dimension s4 Width dimension S Autonomous vacuum cleaner Sh Main body (body)

Claims (2)

A suction fan for generating a negative pressure, a suction port for sucking dust on the surface to be cleaned by the negative pressure of the suction fan, and a dust collecting case for collecting dust arranged between the suction fan and the flow path of the suction port. In an autonomous vacuum cleaner equipped with at least two wheels for autonomous driving,
The wheel includes a shaft that rotates by input of a drive source and supports the load of the vehicle body, and a deceleration mechanism provided between the shaft and the wheel.
The deceleration mechanism
Consists of multiple speed reduction gears
It is arranged in a region equal to or less than the outer diameter of the drive wheels when viewed in the direction of the rotation axis of the drive wheels that are rotated by the drive of each traveling motor.
When viewed in the front-rear direction, a part or all of the reduction gears constituting the reduction mechanism are located within the area of the width dimension of the drive wheels.
The final reduction gear is an autonomous traveling type vacuum cleaner characterized in that the reduction gear uses the inscribed trochoid curve to decelerate. In the autonomous traveling type vacuum cleaner according to claim 1.
The reduction mechanism is an autonomous traveling type vacuum cleaner characterized in that it has two planetary gears using a trochoid curve and is positioned 180 ° apart.

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