JP4712518B2 - Geared motor used for drive device of foldable electric wheelchair - Google Patents

Description

The present invention relates to a geared motor used in a drive device for a foldable electric wheelchair.

  In recent years, with the spread of flattening of roads, sidewalks, etc., or flattening of indoor floors, wheelchairs have become more difficult for people to walk with as well as people with physical disabilities or hospitals. It has become widely used by people who move within.

  People using wheelchairs often have difficulty driving their wheels manually. Moreover, the attendant is not always accompanied by the side. Against this background, many so-called electric wheelchairs that drive the wheel shafts by the power of motors have recently been proposed (see, for example, Patent Document 1).

  FIG. 4 shows an example of an electric wheelchair disclosed in Patent Document 1.

  The wheelchair 1 includes a frame 2 forming a skeleton, an auxiliary wheel 4 attached to the front of the frame 2 (left side in FIG. 4), a drive wheel 5 attached to the rear of the frame 2 (right side in FIG. 4), A driving operation panel 6 is provided above the front of the frame 2. The wheelchair 1 can drive the wheel shaft 12 of the drive wheel 5 by a battery 7 and a motor (not shown). The motor is arranged such that its motor shaft (not shown) is parallel to the wheel shaft 12, and power is transmitted to the wheel shaft 12 via a parallel shaft gear mechanism (not shown).

JP 2000-70304 A

  In particular, when use in a hospital or home is considered, the drive device for an electric wheelchair is required to have low noise. In addition, the vibration is required to be as small as possible. Furthermore, light weight and compactness are important requirements.

  However, conventional electric wheelchair drive devices do not always meet these requirements.

The present invention has been developed in consideration of such a current situation, and is applied to a drive device for a foldable electric wheelchair that can simultaneously realize characteristics such as low noise, low vibration, light weight, and compact. The object is to provide a suitable geared motor.

The present invention comprises a motor and a reduction gear that decelerates the rotation of the motor, and a geared motor used in a drive device for a foldable electric wheelchair that drives a wheelchair wheel by the power of the motor. Haipoidopinio down to the motor shaft integrally with the rotation of the motor, provided on the intermediate shaft the hypoid pinion capable of meshing Haipoidogi ya, and intends second stage pinion meshes provided on the intermediate shaft parallel to disposed intermediate shaft output gear is provided an output shaft, it is a configuration wherein they are accommodated in the casing, and the motor, the axis of the motor shaft is arranged in the axis perpendicular direction of the wheel shaft of the drive wheels of the electric wheelchair Rutotomoni, both the reduction gear and the motor in the geared motor is being configured to be accommodated radially inward of the outer periphery of the wheel of the electric wheelchair Further, by disengaging possible clutch mechanism is disposed by a handle provided outside Oite the casing above the said output shaft a longitudinal direction of the speed reducer, it is obtained by solving the above problems .

  In the present invention, since the motor shaft of the motor can be arranged in a direction perpendicular to the wheel shaft of the wheelchair, it is excellent in compactness.

  In other words, according to the present invention, since the hypoid reduction mechanism having the hypoid pinion and the hypoid gear is interposed and arranged between the motor shaft and the wheel shaft, it is possible to realize the change in the perpendicular direction and the reduction of the rotation axis at the same time. Moreover, since the reduction ratio can be made higher than that of, for example, a bevel gear or the like, the number of reduction stages of the entire drive device can be reduced (for example, reduced from 3 to 2). This reduction in the number of speed reduction stages contributes to the realization of a lightweight and compact geared motor.

  Further, in the present invention, the basic configuration is utilized so that both the reduction gear portion and the motor portion, that is, “the entire geared motor” can be accommodated radially inside the outer periphery of the wheel of the electric wheelchair. As a result, the outermost end in the motor shaft direction, which is the longest, is housed inside the outer periphery of the wheel in the radial direction, and the degree of freedom for mounting the wheel drive system is dramatically improved. Wheelchairs are required to be folded due to their nature, and various accessories may be mounted on recent wheelchairs, and such requests can be flexibly accommodated.

  Furthermore, since the hypoid speed reduction mechanism can be set to a large meshing rate, low noise and low vibration can be realized, and transmission efficiency is not so low, so there is almost no increase in battery power consumption, and electric wheelchairs The drive system has preferable characteristics.

According to the present invention, various characteristics such as light weight, compactness, quietness, and low vibration required for a foldable electric wheelchair can be realized simultaneously.

  Hereinafter, examples of embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a partially broken front view showing the main configuration (geared motor portion) of a drive device for an electric wheelchair to which the present invention is applied, FIG. 2 is a longitudinal sectional view thereof, and FIG. 3 shows the entire drive device. (A) is a plan view and (B) is a front view.

  With reference to FIG. 3, it demonstrates from the whole schematic structure of this drive device. FIG. 3 shows a drive device 24 for a drive wheel (wheel) 22 on one side of the electric wheelchair 20. In addition, since the drive device of the other side drive wheel is comprised completely symmetrically with this, illustration is abbreviate | omitted.

  As shown in FIG. 3, the drive device 24 includes a hypoid geared motor 30 having a DC motor 26 and a hypoid reducer 28. The DC motor 26 is arranged such that the axis O1 of the motor shaft 26A is perpendicular to the axis O2 of the wheel shaft 32 of the drive wheel 22 of the electric wheelchair 20, and the hypoid geared motor 30 rotates 90 degrees. It is set as the structure converted. The output shaft (45) of the hypoid geared motor 30 also serves as the wheel shaft 32 of the drive wheel 22 of the electric wheelchair 20 as it is.

  With reference to FIGS. 1 and 2, a hypoid pinion 34 is geared at the tip of the motor shaft 26 </ b> A of the DC motor 26. The hypoid pinion 34 faces the main body 36 </ b> A of the casing 36 of the hypoid reduction gear 28 and meshes with the hypoid gear 40. The hypocenter of the hypoid pinion 34 (that is, the central axis of the motor shaft 26A) O1 and the central axis O3 of the intermediate shaft 42 to which the hypoid gear 40 is mounted intersect each other at right angles in plan view with a shift amount E1 therebetween. .

A second stage pinion 44 is directly formed on the intermediate shaft 42. The second stage pinion 44 meshes with an output gear 46 that is slidably mounted on the output shaft 45. The output shaft 45 is disposed parallel to the intermediate shaft 42 via bearings 47 and 49 (that is, at right angles to the motor shaft 26A), and also serves as the wheel shaft 32 of the drive wheel 22 of the electric wheelchair 20 as described above. It is configured . A male spline (external gear) 45 </ b> A is formed on a part of the outer periphery of the output shaft 45. On the other hand, an output gear 46 is slidably mounted on the output shaft 45. The output gear 46 is formed with a female spline 46A that can be engaged with the male spline 45A on its inner periphery. That is, the output gear 46 is an external gear that meshes with the second-stage pinion 44 and at the same time is an internal gear that meshes with the male spline 45A.

  The output gear 46 has a ring-shaped recess 46B in a part of its outer periphery, and the locking portion 48A of the slide body 48 is engaged with the recess 46B. The slide body 48 is slidable along a slide pin 50 provided separately in parallel with the output shaft 45. A cam surface 48B is formed on the slide body 48 on the side opposite to the locking portion 48A (above the hypoid geared motor 30). On the other hand, the handle 52 is provided with an eccentric cam shaft 54 that rotates integrally with the handle 52 around the central axis H1. A pin 56 is incorporated in the eccentric cam shaft 54 at a predetermined distance L2 from the central axis H1. That is, the pin 56 can revolve with respect to the central axis H1 as the handle 52 rotates, and the cam surface 48B of the slide body 48 can be pressed by this revolution. Since the slide body 48 can move only along the slide pin 50, a driving force (component force) in the direction of the slide pin 50 of the slide body 48 is obtained by the pressing force from the pin 56 side. The slide body 48 is always urged by the spring 60 in the left direction in the figure (the direction in which the female spline 46A of the output gear 46 is engaged with the male spline 45A of the output shaft 45).

  The handle 52, the eccentric cam shaft 54, the slide body 48, the female spline 46A of the output gear 46, and the male spline 45A of the output shaft 45 connect and disconnect the power transmission between the wheel shaft 32 (output shaft 45) and the hypoid gear 40. A possible clutch mechanism 62 is configured.

  On the other hand, the casing 36 of the hypoid reduction gear 28 is mainly composed of a main body 36 </ b> A and a cover 36 </ b> B, and is integrated by a mounting bolt 66 via a seal ring 64. The cover 36B includes support holes 70, 72, and 74 for supporting each axis in the hypoid reducer 28, that is, the intermediate shaft 42, the output shaft 45, and the slide pin 50, and the main body 36A side of the casing 36 corresponds. Support holes 76, 78, 80 are provided. The intermediate shaft 42 can be rotated by bearings 82 and 83, the output shaft 45 can be rotated by bearings 48 and 49, and the slide pin 50 can be directly rotated by these support holes 70, 72, 74, 76, 78 and 80. It is supported by. The centers of the support holes 70, 72, 74 formed on the cover 36B side are arranged on the same virtual plane S1, and the mounting bolt 66 for mounting the cover 36B on the main body 36A side is inserted. The mounting holes (see the corresponding holes 68 on the main body 36A side) are formed symmetrically with respect to the virtual plane S1. This is a configuration for enabling the hypoid reduction gear 28 to be used for any of the left and right drive wheels 22 of the electric wheelchair 20 including its cover 36B.

  The hypoid reducer 28 is incorporated into a frame (not shown) of the electric wheelchair 20 via the bolt hole 78 symmetrically, and the left and right drive wheels 22 are mounted on the respective output shafts 45. A male screw 45 </ b> C formed at the tip of the output shaft 45 is for screwing a nut (not shown) for stopping the drive wheel 22. That is, the hypoid reducer 28 functions as a “bearing box” that supports the drive wheels 22 of the electric wheelchair 20 in a cantilevered state as a whole.

As apparent from the depiction in FIG. 3, in this embodiment, the hypoid speed reducer 28 in the hypoid geared motor 30 has a longitudinal size of X, while the DC motor 26 has a longitudinal direction ( magnitude of the axial O1) is Y, together, there is a radially inwardly housed et configurations of the outer peripheral D of the drive wheel 22 of the electric wheelchair 20.

  A reference numeral 81 in the figure is a positioning mechanism for the eccentric cam shaft 54 including a bolt 81A, a spring 81B, and a ball 81C, and is for restricting the movement of the eccentric cam shaft 54 in the direction of the central axis H1. Reference numeral 82 denotes a bolt for connecting the DC motor 26 to the main body 36 </ b> A of the casing 36 of the hypoid reduction gear 28.

  Next, the operation of the drive device 24 of the electric wheelchair 20 according to this embodiment will be described.

  When the motor shaft 26A of the DC motor 26 rotates, the hypoid pinion 34 formed at the tip of the motor shaft 26A rotates integrally. When the hypoid pinion 34 is rotated, it is transmitted to the hypoid gear 40 meshing with the hypoid pinion 34, and the second-stage pinion 44 formed by gear cutting directly on the intermediate shaft 42 is rotated. The rotation of the second stage pinion 44 is transmitted to the output gear 46.

  During normal use, the handle 52 is positioned at the position indicated by the solid line in FIG. 2 by the function of the spring 60, so that the female spline 46A of the output gear 46 meshes with the male spline 45A of the output shaft 45. Thus, the rotation of the output gear 46 directly becomes the rotation of the output shaft 45 (that is, the wheel shaft 32), and the drive wheel 22 is rotated.

  On the other hand, for example, when moving in the home, it may be more convenient for the occupant to rotate the driving wheel 22 by hand directly rather than driving by a DC motor. In such a case, if the wheel shaft 32 (that is, the output shaft 45) is connected to the motor shaft 26A via the second stage pinion 44, the hypoid gear 40, and the hypoid pinion 34, a large driving resistance is generated. Therefore, in this case, the pin 56 of the eccentric cam shaft 54 is revolved with respect to the central axis H1 by rotating the handle 52. Then, by this revolution, the slide body 48 can obtain the axial component force of the slide pin 50 from the pin 56 via the cam surface 48B, and the slide body 48 overcomes the biasing force of the spring 60 and moves to the right in FIG. The output gear 46 is slid rightward in FIG. 2 through the locking portion 48A. As a result, the engagement of the female spline 46A of the output gear 46 and the male spline 45A of the output shaft 45 is released, and the output shaft 45 (wheel shaft 32) is disconnected from the power transmission system from the DC motor 26. As a result, the occupant can easily rotate the drive wheels 22 due to the presence of the clutch mechanism 62.

  Further, the clutch mechanism 62 is slid along the output shaft 45 with respect to the male spline 45A formed on the output shaft 45 along the output shaft 45, so that the male spline 45A and the female spline 46A Since the engagement and disengagement are performed, the configuration of the clutch mechanism 62 itself is simple, and the cost can be reduced.

  Further, since the slide along the output shaft 45 of the output gear 46 is realized by the slide body 48 that can slide on the slide pin 50 arranged in parallel with the output shaft 45, the space is relatively large. Thus, the space above the wheel shaft 32 with the wheel can be used effectively, and the space below the wheel shaft 32 can be secured larger. As a result, it is possible to drive across a small obstacle and increase the degree of freedom of travel.

  As is apparent from FIG. 3, in this embodiment, the hypoid speed reducer 28 in the hypoid geared motor 30 has a size in the longitudinal direction of X, while the DC motor 26 has a longitudinal direction (axial direction O1). Is Y, and both are stored inside the outer periphery D of the drive wheel 22 of the electric wheelchair 20 in the radial direction. For this reason, the hypoid geared motor 30 does not have a possibility of causing a situation that hinders traveling when the hypoid geared motor 30 is attached.

  In particular, in this drive device 24, since the output shaft 45 of the hypoid reduction gear 28 directly serves as the wheel shaft 32 of the drive wheel 22 of the electric wheelchair 20, the structure of the drive system is simple, and the hypoid geared motor 30. Of the hypoid geared motor 30 that is farthest from the axis O2 when mounted in any direction of 360 degrees parallel to the rotation plane P1 of the drive wheel 22 with the axis O2 of the wheel shaft 32 as the center. The outermost end R <b> 1 is always within the radial direction from the outer periphery D of the drive wheel 22. Therefore, the degree of freedom of mounting can be dramatically increased, and it is possible to flexibly cope with the design of the configuration for folding the electric wheelchair 20 and the equipment of various accessories.

  Further, since the casing 36 of the hypoid reducer 28 functions as a bearing box for the drive wheel 22 of the electric wheelchair 20, the attachment and removal of the drive wheel 22 is easy, and maintenance is easy.

  Further, a mounting hole for the main body 36A in the cover 36B of the casing 36, a corresponding hole 68 on the main body 36A side corresponding thereto, and support holes 70, 72, 74 for supporting the respective shafts 42, 45, 50 of the speed reducer 28. , 76, 78, 80 are respectively formed with respect to virtual planes connecting the centers of the support holes 70, 72, 74, 76, 78, 80. It can also be used for each hypoid geared motor 30 of the drive wheel 22. That is, for the main body 36A whose right side in the drawing as shown in FIG. 2 is open, and also for the main body (not shown) whose left side is open (used for the other drive wheel 22). Also, the same cover 36B can be used. Therefore, the cost of the entire electric wheelchair 20 can be reduced.

The present invention provides a geared motor for driving an electric wheelchair with low cost and high performance that can simultaneously realize the characteristics of light weight, compactness, quietness, and low vibration required for a foldable electric wheelchair. become able to.

The partially broken front view which shows the main structures (geared motor part) of the example of the drive device of the electric wheelchair to which this invention was applied Sectional view along the line II-II in FIG. This shows the entire drive device, where (A) is a plan view and (B) is a front view. Side view showing the overall configuration of a conventional electric wheelchair

Explanation of symbols

DESCRIPTION OF SYMBOLS 20 ... Electric wheelchair 22 ... Drive wheel 24 ... Drive apparatus 26 ... DC motor 26A ... Motor shaft 28 ... Hypoid reducer 30 ... Hypoid geared motor 32 ... Wheel shaft (output shaft)
34 ... Hypoid pinion 36 ... Casing 36A ... Main body 36B ... Cover 40 ... Hypoid gear 42 ... Intermediate shaft 44 ... Second stage pinion 45 ... Output shaft (wheel shaft)
45A ... Male spline 46 ... Output gear (internal gear)
46A ... Female spline (external gear)
48 ... Slide body 50 ... Slide pin 52 ... Handle 54 ... Eccentric cam shaft 56 ... Pin 60 ... Spring 70, 72, 74, 76, 78, 80 ... Support hole

Claims (4)

In a geared motor used in a foldable electric wheelchair drive device that includes a motor and a speed reducer that decelerates rotation of the motor, and that drives a wheelchair wheel by the power of the motor,
The reduction gear, provided Haipoidopinio emissions, provided in the intermediate shaft the hypoid pinion capable of meshing Haipoidogi Ya, and the intermediate shaft parallel to arranged the intermediate shaft to the motor shaft integrally with the rotation of the motor 2 an output shaft stage pinion meshed with the output gear is provided, it is a configuration wherein they are accommodated in the casing, and
The motor is arranged such that the axis of the motor shaft is perpendicular to the axis of the wheel shaft of the drive wheel of the electric wheelchair, and both the speed reducer and the motor in the geared motor are the motor wheel of the electric wheelchair. It is configured to be stored inside the outer periphery of the wheel in the radial direction,
Furthermore, the longitudinal direction is a by foldable electric wheelchair, characterized in that the handle provided outside Oite the casing above the said output shaft disengaging possible clutch mechanism is disposed in said speed reducer A geared motor used in a drive unit. In claim 1,
The geared motor used for the drive device of the foldable electric wheelchair characterized in that the output shaft of the speed reducer also serves as the wheel shaft of the wheel of the electric wheelchair. In claim 2,
A geared motor used in a drive device for a foldable electric wheelchair, wherein a casing of the speed reducer functions as a bearing box for the wheel of the electric wheelchair. In any one of Claims 1-3,
The speed reducer includes a casing main body and a casing cover, and a support hole for supporting each shaft in the speed reducer formed in the casing cover and a mounting hole for attaching the casing cover to the casing main body are provided. Foldable, characterized by being formed symmetrically with respect to a virtual plane connecting the centers of the support hole for supporting the output shaft on the casing cover and the support hole for supporting the hypoid gear. A geared motor used in a drive device for an electric wheelchair.

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