JP2746356B2 - Floor reaction force meter - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a floor reaction force meter used for gait analysis and balance function training of a subject such as a patient in the field of orthopedics and rehabilitation.

[0002]

2. Description of the Related Art Conventionally, in the field of orthopedic surgery and rehabilitation, etc., a change in the load acting on both feet of a subject using a floor reaction force meter for gait analysis and balance function training of the subject such as a patient. And the movement trajectory of the center of the load and the swinging state of the position of the center of gravity of the subject are detected. As an example of the structure of the floor reaction force meter, a structure shown in FIG. 1 is known. ing.

The floor reaction force meter 1 has a rectangular base plate 2, three-component load cells 3 attached to the four corners of the base plate 2, and is supported by these three-component load cells 3. And a plate-like platform 4 constituting Each of the three-component load cells 3 is provided with a load acting on the platform 4 in two directions orthogonal to each other along the surface direction of the platform 4 (hereinafter, these two axes are referred to as an X axis and a Y axis). X-axis component force detector and Y
An axial component force detector and a Z-axis direction component force detector that detects a component force in an axis direction (hereinafter, referred to as a Z axis) perpendicular to the surface of the platform 4 are provided.

[0004] The floor reaction force meter 1 uses a detection result from each component force detector of each three-component load cell 3 and information on moment about each axis to distribute weight, drive force, and control during walking. Information such as power, weight transfer (in a standing state, the center of gravity fluctuates), torsional force, stride, walking speed, walking stability, and balance in a standing posture is obtained.

[0005]

However, such a conventional floor reaction force meter 1 has the following problems to be improved. That is, in the floor reaction force meter, it is desired that the platform 4 has a rigid structure as much as possible in order to suppress the transmission loss of the load to each component force detector. Therefore, in the conventional floor reaction force meter 1, the above problem is dealt with by increasing the thickness of the platform 4 described above. However, when the thickness of the platform 4 is increased in this way, the mass of the platform 4 is increased, and not only the accuracy of detecting the component force and the responsiveness are impaired, but also the natural frequency of the platform 4 is reduced. As a result, the frequency approaches the resonance frequency of the subject, and the instrument may resonate during measurement, making accurate measurement impossible.

In order to prevent the occurrence of such inconveniences, measures such as using a lightweight and highly rigid material for the platform 4 can be considered. In general, a material satisfying such conditions has a high unit price. This may not be an effective solution because it causes an increase in the production cost of the apparatus, and the available materials are limited and the degree of freedom in design is reduced.

The present invention has been made in view of the above-mentioned conventional problems, and has as its object to provide a floor reaction force meter capable of reducing the weight while securing the rigidity of the platform.

In order to achieve the above object, a floor reaction force meter according to claim 1 of the present invention has a platform on which a load is applied, and a load detector that supports the platform and detects the center of the load. A floor reaction force meter comprising:
Pair of plates and the center of these plates
And a cylindrical rib provided in an annular shape
Plural provided radially from the edge to the edge of the plate
And a radial rib.

[0009]

According to the floor reaction force meter according to claim 1 of the present invention,
A pair of plays in which the platforms are arranged facing each other
To the center of these plates
Cylindrical rib and the edge of the plate
A plurality of radial ribs provided radially toward the
Provision of a box-shaped section at any position
And the force in the falling direction of each radial rib
Is supported by other ribs, ensuring high rigidity.
The preservation has been made. Further, since a space is formed between the two plates and between the ribs, an increase in the mass of the platform is suppressed.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIGS. Reference numeral 10 in FIG. 2 indicates a floor reaction force meter according to the present embodiment. The floor reaction force meter 10 includes a rectangular base plate 11, a rectangular platform 12 opposed to the base plate 11, An X-direction component force detector 13 and a Y-direction component force detector which respectively detect component forces of the load acting on the platform 12 in the X direction and the Y direction orthogonal to the plane direction of the platform 12. As shown in FIG. 3, a pair of the X-direction component force detector 13 and the Y-direction component force detector 14 are provided, and the X-direction component force detector 13 and the Y-direction component force are provided. The detector 14 has a schematic configuration in which the detector 14 is disposed at an intermediate position of the length of the platform 12 in each component force detection direction.

To explain these details, the platform 12 includes a pair of similar upper and lower plates 12a and 12b, and a plurality of ribs 15 connecting these plates 12a and 12b in parallel with each other. In this embodiment, the short sides of the plates 12a and 12b are defined as the X direction, the long sides are defined as the Y direction, and the direction perpendicular to the surface of the upper plate 12a is defined as The Z direction is set.

The plurality of ribs 15 are formed of a cylindrical rib 15a disposed coaxially at the center of the surfaces of the plates 12a and 12b, and as shown in FIG.
a pair of first ribs 15b disposed in parallel with the X direction at an intermediate position of the long sides of a.12b (where L is the length of the long side, and a position L / 2 from one end of the long side). , Both plates 1
A pair of second ribs 15c disposed in parallel with the Y direction at an intermediate position of the short sides of 2a and 12b (where W is the length of the short side and w / 2 from one end of the short side). , And four third ribs 15d arranged from the center of the plates 12a and 12b to the respective corners.

The ribs 15a to 15d
As shown in FIGS. 4 and 5, a part thereof is integrally attached to the two plates 12a and 12b with bolts 16 and the shape of a cut surface along a plane orthogonal to the two plates 12a and 12b is a box shape. Thus, the platform 12 has a rigid structure. In particular, a cylindrical rib 15a is provided at the center of the platform 12, and further, other ribs 15b, 15c, and 15d are provided.
Are radially provided from the central portion of the platform 12, so that the force in the falling direction of each of the ribs 15a to 15d is supported by the other ribs, so that high rigidity is ensured. Further, each of these ribs 15
By a to 15d, a large space is formed inside the platform 12 to provide a lightweight platform 12.

On the other hand, the first rib 15b is provided at a peripheral end of the platform 12 with a fixing means 17 provided on the base plate 11, as shown in FIG.
And is separated from both plates 12a and 12b of the platform 12, as shown in FIG. In addition, the first rib 15b is provided on the platform 12
As shown in FIG. 3, notches 18 are provided on both sides in the Y direction on the inner side of the connection with the fixing means 17 at the portions separated from the fixing means 17, and further, on both sides in the Z direction (that is, in the vertical direction) ), A hole 19 having a predetermined inner diameter is formed at a predetermined depth, so that a load detection wall 20 parallel to the surface of the platform 12 is formed inside. Thereby, one end of the first rib 15b is elastically deformed under a predetermined spring constant based on the shape set by the notch 18 and the hole 19, the thickness of the load detection wall 20, and the like. It is supposed to be.

A strain gauge (not shown) for detecting the strain in the Y direction of the load detecting wall 20 is provided on the load detecting wall 20.
Is attached, the Y-direction component force detector 1
4 are configured.

On the other hand, one end of the second rib 15c has a relationship that the relative position to the one end of the first rib 15b is shifted by 90 ° in the plane direction.
It has the same configuration as b, and is fixed to the base plate 11 by fixing means 17 having the same structure. Then, on the load detection wall 20 of the second rib 15c,
The X-direction component force detector 13 is configured by attaching a strain gauge (not shown) for detecting the strain in the X direction of the load detection wall 20.

Therefore, according to the above configuration, each of the X-direction component force detectors 13 is attached to the side edge of the platform 12 at an intermediate position of the width in the X-direction.
Each Y-direction component force detector 14 is mounted at an intermediate position in the Y-direction width.

In this embodiment, as shown in FIGS. 2 and 3, the fixing means 17 has a U-shaped block 21 fixed to the base plate 11, and stands on both ends of the U-shaped block 21. It is constituted by a support bolt 22 provided through the provided leg portion 21a, and a plurality of nuts 23 screwed to the support bolt 22.

As shown in FIG. 3, one end of the first rib 15b or the second rib 15c is located between the two legs 21a of the U-shaped block 21, and the support bolt 22 is inserted therethrough. As a result, the first rib 15b or the second rib 15c is supported by the U-shaped block 21, and the respective leg portions 21a and the first rib 15b are fixed by the nuts 23 screwed to the support bolts 22. Alternatively, these are fixed by the second rib 15c being sandwiched. Further, by changing the position of the nut 23 that holds the first rib 15b or the second rib 15c, the base plate 1
1 of the first rib 15b and the second rib 15c with respect to Y
It is possible to adjust the relative position in the direction and the X direction.

Further, in this embodiment, each of the third
At the end of the rib 15d on the side edge side of the platform 12,
A Z-direction component force detector 24 for detecting a component force of the load acting on the platform 12 in a direction perpendicular to the surface thereof is provided.

The Z-direction component force detector 24 will be described in detail. The end of each of the third ribs 15d is, as shown in FIG.
It is separated from the base 12b and is fixed so as to be sandwiched by a pair of nuts 26 on support bolts 25 which are planted in the base plate 11 in the vertical direction.

A hole 27 having a predetermined inner diameter is formed at a predetermined depth from both sides along the surface direction of the platform 12 inside the support bolt 25, and a load detecting wall 28 is formed inside. And the notch 29 having a predetermined depth from both sides in the Z direction (that is, from the vertical direction), the shape formed by the hole 27 and the notch 29 and the load detection wall 2
8 can be elastically deformed based on a spring constant determined by the thickness or the like. The third thus configured
The Z-direction component force detector 24 is formed by attaching a strain gauge (not shown) for detecting a load in the Z-direction to the load detection wall 28 at the end of the rib 15d.

Each of these Z-direction load detectors 24
Are two nuts 2 for fixing these to the support bolts 25.
By performing the position adjustment of 6, the position adjustment of the fixed portion with respect to the base plate 11 in the Z direction is performed.

In the floor reaction force meter 10 of the present embodiment having the above-described structure, when the load applied to the platform 12 when the subject rides on the platform 12, the load is applied in the X direction.
Each component force detector 13 is provided for each component force in the Y direction and the Z direction.
・ Detected by 14.24 and used for various analyzes and training.

When detecting such a load,
The platform 12 comprises a pair of opposing plates 12
a and 12b are connected to each other by a plurality of ribs 15a to 15d, and a cross section at an arbitrary position has a box-shaped high rigidity structure. -The transmission loss of the load transmitted to 24 is suppressed. As a result, highly accurate load detection is performed.

The cross section of the platform 12 at an arbitrary position is formed in a box shape, so that a large space is formed therein.
2 is significantly reduced, and as a result, the natural frequency of the platform 12 is increased, and resonance at the time of load detection is prevented. From this point, load detection with high accuracy is possible.

On the other hand, in the present embodiment, the platform 12 is supported by an X-direction component force detector 13 and a Y-direction component force detector 14 at an intermediate position in the length direction of the platform 12 in the X and Y directions. Accordingly, even when the platform 12 is deformed in the plane direction due to heat due to a change in the installation environment temperature or the like, the thermal deformation of the platform 12 is caused by the component force detectors 13 and 14 as a center. Since the force is generated toward both sides in the component force detection direction, the load acting on each of these component force detectors 13 and 14 based on the thermal deformation is significantly reduced. Therefore, the influence of the change in the installation environment temperature is reduced, stable measurement is performed, and the adjustment work at the time of installation of the floor reaction force meter 10 and at the time of initial setting before the start of the measurement is simplified.

As described above, the floor reaction force meter according to the present invention comprises a platform on which a load is applied, and a floor reaction force sensor having a load detector that supports the platform and detects the load center. Total and before
A pair of plates on which the platform is opposed
And are provided annularly with respect to the center of these plates
Cylindrical rib and the edge of the plate from the periphery of this cylindrical rib
A plurality of radial ribs provided radially toward
It has the following excellent effects.

Disconnection at any position on the platform
The surface has a box-shaped structure, and how each radial rib falls
The force in the direction is supported by other ribs to make a high rigid structure
Thus, the transmission loss of the load transmitted to each of the component force detectors is suppressed, so that the load can be detected with high accuracy.

In addition, a large space is formed inside the platform to reduce the weight of the platform. As a result, the natural frequency of the platform can be increased, and resonance at the time of load detection can be prevented. Detection accuracy can be improved.

[Brief description of the drawings]

FIG. 1 is a perspective view schematically showing a conventional floor reaction force meter.

FIG. 2 is a perspective view schematically showing a floor reaction force meter according to an embodiment of the present invention, with a part thereof being omitted.

FIG. 3 is a plan view schematically showing a floor reaction force meter according to one embodiment of the present invention, with a part thereof being omitted;

FIG. 4 is a longitudinal sectional side view of an X-direction component force detector or a Y-direction component force detector, showing a floor reaction force meter according to one embodiment of the present invention.

FIG. 5 is a longitudinal sectional side view of a Z-direction component force detector, showing a floor reaction force meter according to one embodiment of the present invention.

[Explanation of symbols]

 Reference Signs List 10 floor reaction force meter 11 base plate 12 platform 12a upper plate 12b lower plate 13 component detector in X direction 14 component detector in Y direction 15 rib 15a cylindrical rib 15b first rib 15c second rib 15d third rib 17 fixing means 24 Z direction component force detector 25 Support bolt 26 Nut

Claims (1)

(57) [Claims] 1. A floor reaction force meter including a platform on which a load is applied, and a load detector that supports the platform and detects the center of the load, wherein the platform has a pair of opposed surfaces. No
Rate and the center of these plates
The cylindrical rib that has been
Radial ribs radiating toward the edge of the
And a floor reaction force meter.