JP4603414B2 - Ultrasonic bone densitometer - Google Patents

Description

The present invention relates to an ultrasonic bone density measuring device used for diagnosis of osteoporosis and the like.

In order to diagnose osteoporosis, an ultrasonic bone density measuring device that measures bone characteristics by penetrating ultrasound into bone and measuring the speed of sound (SOS) in the bone has already been proposed. ing. As a measuring apparatus for performing such measurement, for example, there are devices disclosed in Patent Document 1 and Patent Document 2.

The “ultrasonic tissue evaluation apparatus” disclosed in Patent Document 1 employs a single feed screw as means for sandwiching a subject between a pair of opposed specimen contact portions. By rotating a handle for rotating the feed screw, the two specimen contact portions incorporated in the feed screw are interlocked symmetrically so as to sandwich the subject. In addition, in this “ultrasonic tissue evaluation apparatus”, a torque limiter is provided between the feed screw and a handle for rotating the feed screw. After the specimen contact portion comes into contact with the subject, the feed screw is further rotated. By continuing, the torque limiter is operated, and the driving of the two specimen contact portions is stopped simultaneously.

In addition, the “ultrasound bone diagnostic apparatus” disclosed in Patent Document 2 is provided with separate handles for driving the pair of specimen contact portions, respectively, and by operating the pair of specimen contact portions individually. A pair of specimen contact portions can be individually operated.
Japanese Patent No. 3218224 Japanese Patent No. 2821466

However, in the “ultrasonic tissue evaluation apparatus” described in Patent Document 1, since two specimen contact portions are incorporated in one feed screw, the two specimen contact portions are rotated by rotating the feed screw. Are interlocked symmetrically, and the torque limiter for controlling the driving force is activated when the rotation of the feed screw is further continued from the state in which one specimen contact portion is in contact with the subject. Therefore, when the subject is not at the center position between the two specimen contact portions, the torque limiter is activated when one of the specimen contact portions contacts the subject, and the movement of the feed screw and the specimen contact portion is stopped. One specimen contact portion has a problem that it does not contact the subject.

Further, in the “ultrasonic bone diagnostic apparatus” described in Patent Document 2, since the specimen contact portions on both sides can be individually operated, even when the subject is not at the center position of both specimen contact portions. It is possible to sandwich the subject. However, since the handles are individually provided, the operation is complicated, and the pressure for bringing the sample contact portion into contact with the subject depends on the sense of the operator of the handle. There was a problem that the subject could not be sandwiched with equal pressure.

The present invention has been made in view of such a problem. Regardless of whether or not the subject is at the center position of the pair of specimen contact portions, the subject can be removed from both sides by a single driving operation of the specimen contact portion. An object of the present invention is to provide an ultrasonic bone density measuring device that can be clamped with an equal pressure.

In order to solve the above-mentioned problems, the present invention is an ultrasonic bone density measuring apparatus that sandwiches a subject between a pair of opposing specimen contact portions and transmits the ultrasonic signal to the subject to measure the characteristic of the subject. Two driving mechanisms that respectively drive the specimen contact portion with a single driving source, and when the pressing force on the subject exceeds a predetermined value, the driving mechanism drives the specimen contact portion individually. And a controller for stopping the operation.

With this configuration, the driving of the specimen contact portion by the drive mechanism can be individually controlled, and the subject can be clamped from both sides with equal pressure by the specimen contact portion by a single driving operation of the specimen contact portion.

The present invention also relates to an ultrasonic bone densitometer for measuring a characteristic of a subject by holding the subject between a pair of opposed specimen contact portions and transmitting an ultrasonic signal to the subject, the center of which is the axis. A shaft that rotates in rotation, two drive mechanisms that individually drive the specimen contact portion using the rotational movement of the shaft, and a shaft that is provided on the same axis as the shaft. Two torque limiters that individually stop driving of each specimen contact portion by the drive mechanism when the pressure in the direction opposite to the rotation of the shaft transmitted to the drive mechanism exceeds a predetermined value. It is what.

With this configuration, by adjusting the set values of the two torque limiters to the same set value, the subject can be clamped from both sides with equal pressure by the specimen contact portion by a single driving operation of the specimen contact portion.

The present invention employs a rack and pinion system as the drive mechanism of the invention.

With this configuration, the same effect as that of the first aspect of the invention can be obtained even in an ultrasonic bone density measuring apparatus using a rack and pinion system.

The present invention employs a feed screw system as the drive mechanism of the invention.

With this configuration, the same effect as that of the first aspect of the invention can be obtained even in an ultrasonic bone density measuring apparatus using a feed screw system.

Further, the present invention replaces the method of individually controlling the driving of the specimen contact portion using the two torque limiters, and individually drives the specimen contacting portion using two sliding mechanisms by two wire pulleys. It is intended to be controlled.

With this configuration, by adjusting the tension of the two wires to be the same, the subject can be clamped from both sides with equal pressure by the specimen contact portion by a single driving operation of the specimen contact portion.

According to the present invention, when the subject is clamped by the pair of opposed sample contact portions, even if the subject is not at the center position of the pair of sample contact portions, the drive operation of the sample contact portion is performed once. Thus, an effect is obtained that the subject can be held at the same pressure from both sides by the specimen contact portion.

Embodiments of the present invention will be described below with reference to the drawings.
(Embodiment 1)
The ultrasonic bone density measuring apparatus according to the first embodiment of the present invention is such that two torque limiters are provided on a shaft that can be operated by a user, and a pair of specimen contact parts are individually controlled by a control part. is there. Here, a torque limiter is used as a control unit that individually controls the specimen contact unit.

FIG. 1 is a diagram showing an example of the configuration of an ultrasonic bone density measuring apparatus according to Embodiment 1 of the present invention. FIG. 2 is a side view of the apparatus in which a manual dial is attached to the shaft of the ultrasonic bone density measuring apparatus shown in FIG.

In the ultrasonic bone density measuring apparatus shown in FIG. 1 and FIG. 2, the specimen contact portion 1 and the specimen contact portion 2 are arranged so as to face each other so that the subject to be measured can be sandwiched from both sides. Each has an ultrasonic transducer for transmitting and receiving ultrasonic waves. Note that the ultrasonic transducers included in the sample contact unit 1 and the sample contact unit 2 may be fixed types that do not move, and only the sample contact unit 1 and the sample contact unit 2 move to pinch the subject. It may be what you do.

The shaft 3 is rotated about an axis by the user's operation of the manual dial 4, and two pinion gears 7 and 8 are attached to the shaft 3 via torque limiters 5 and 6, respectively. Here, a description will be given of a case where the user manually rotates the shaft 3 by rotating the manual dial 4, but the shaft 3 may be rotated by any method, for example, an electric motor that rotates the shaft 3. good.

Torque limiters 5 and 6 are provided until the specimen contact portions 1 and 2 come into contact with the subject and the pressure transmitted to the pinion gears 7 and 8 via the specimen contact portions 1 and 2 and the racks 9 and 10 becomes a predetermined value or more. Rotates the pinion gears 7 and 8 so as to be linked to the rotational movement of the shaft 3 to drive the specimen contact portions 1 and 2. On the other hand, when the pressure transmitted to the pinion gears 7 and 8 via the sample contact parts 1 and 2 and the racks 9 and 10 becomes a predetermined value or more, the pinion gears 7 and 8 start to idle, The drive of the parts 1 and 2 is stopped. Here, the predetermined value means a threshold at which the torque limiters 5 and 6 operate, and this value can be arbitrarily set in advance.

The rack 9 converts the rotational motion of the pinion gear 7 into a linear motion, and the sample contact portion 1 and the rack 9 are connected so that the sample contact portion 1 is interlocked with the movement of the rack 9.
The rack 10 converts the rotational motion of the pinion gear 8 into a linear motion, and the sample contact portion 2 and the rack 10 are connected so that the sample contact portion 2 is interlocked with the movement of the rack 10. Here, since the distance between the pinion gear 8 and the specimen contact portion 2 is long, the rack 10 is a substantially U-shaped continuous structure for reinforcing the strength of the rack 10 as shown in FIG.

Next, the torque limiters 5 and 6 attached to the shaft 3 will be described in more detail.
FIG. 3 is an enlarged view of a shaft portion of the ultrasonic bone density measuring apparatus according to Embodiment 1 of the present invention.

As shown in FIG. 3, the torque limiters 5 and 6 include nuts 11 and 15 and springs 12 and 16, respectively. The threshold at which the torque limiters 5 and 6 operate can be freely adjusted by the tightening degree of the nuts 11 and 15. it can.

The pinion gears 7 and 8 are rotatably attached to the shaft 3, and sliding plates 13 and 14 or sliding plates 17 and 18 are provided at both ends thereof.

When the torque limiters 5 and 6 having such a configuration are used, the ultrasonic bone density measuring apparatus according to the present invention includes the pinion gear 7 via the specimen contact portions 1 and 2 and the racks 9 and 10 (not shown). The pinion gears 7 and 8 rotate in conjunction with the rotational motion of the shaft 3 by the frictional force between the torque limiters 5 and 6 and the pinion gears 7 and 8 until a constant pressure is applied to the shafts 3 and 8. On the other hand, when a predetermined pressure or more is applied to the pinion gears 7 and 8 via the specimen contact portions 1 and 2 and the racks 9 and 10 (not shown), the pressure in the rotational direction of the shaft 3 applied to the pinion gears 7 and 8. Exceeds the frictional force between the torque limiters 5, 6 and the pinion gears 7, 8, and the pinion gears 7, 8 start spinning with respect to the rotational movement of the shaft 3.

The threshold at which the torque limiters 5 and 6 are operated, that is, the frictional force between the torque limiters 5 and 6 and the pinion gears 7 and 8 can be freely adjusted by tightening the nuts 11 and 15 of the torque limiters 5 and 6. In the ultrasonic bone density measuring apparatus of the present invention, the pinion gears 7 and 8 can be idled under the same conditions by keeping the nuts 11 and 15 tightened in the same degree. The configurations of the torque limiters 5 and 6 shown here are merely examples, and other configurations may be used.

Next, the operation of the ultrasonic bone density measuring apparatus according to Embodiment 1 of the present invention will be described with reference to FIGS.
When the shaft 3 is rotated, the pinion gears 7 and 8 are rotated in conjunction therewith. The rotational movement of the pinion gears 7 and 8 is changed to linear movement by the racks 9 and 10, and the specimen contact portions 1 and 2 provided to face each other are moved.

At this time, if one of the specimen contact portions (here, the specimen contact portion 1 is assumed to be in contact with the subject first), the repulsive force from the subject is passed through the specimen contact portion 1 and the rack 9 to the pinion gear 7. The pressure in the direction opposite to the rotation direction of the shaft 3 applied to the pinion gear 7 gradually increases. Then, when the pressure applied to the pinion gear 7 from the subject via the specimen contact portion 1 and the rack 9 becomes a certain level or more, the pinion gear 7 that is rotatably mounted starts to idle, and the specimen contact portion 1 is driven. Stop. Therefore, if the set value of the torque limiter 5 is always set to the same value, the specimen contact portion 1 can always be brought into contact with the subject with a constant pressure.

Further, the other specimen contact section 2 continues to move even after the one specimen contact section 1 stops. When the specimen contact portion 2 comes into contact with the subject and the pressure in the direction opposite to the rotation direction of the shaft 3 applied to the pinion gear 8 from the subject via the specimen contact portion 2 and the rack 10 becomes a certain level or more, the pinion The gear 8 starts to idle, and the driving of the specimen contact unit 2 is stopped. Therefore, as described above, if the set value of the torque limiter 6 is always set to the same value, the specimen contact portion 2 can be brought into contact with the subject with a constant pressure at all times.

Further, if the set values of the two torque limiters 5 and 6 are set to the same optimum value, the subject can be held from both sides with the same pressure by the pair of opposing specimen contact portions 1 and 2. Become.

As described above, according to the ultrasonic bone density measuring apparatus according to the first embodiment of the present invention, the two torque limiters 5 and 6 are provided on the shaft 3, and a pair of specimens are set according to the set values of the torque limiters 5 and 6. By controlling the contact portions individually, even if the subject is not at the center position of the pair of specimen contact portions 1 and 2, the subject is moved to both sides by a single drive operation of the specimen contact portions 1 and 2. Therefore, it is possible to always hold at the same pressure.

(Embodiment 2)
Next, an ultrasonic bone density measuring apparatus according to Embodiment 2 of the present invention will be described.
The ultrasonic bone density measuring apparatus according to the second embodiment of the present invention uses a feed screw method instead of the rack and pinion method described in the first embodiment of the present invention as a driving mechanism for the specimen contact portion.

FIG. 4 is an explanatory diagram for explaining a drive mechanism of the ultrasonic bone density measuring apparatus according to the second embodiment of the present invention. Note that in the ultrasonic bone density measuring apparatus according to the second embodiment of the present invention, the same components as those of the ultrasonic measuring apparatus according to the first embodiment described above are denoted by the same reference numerals, and description thereof is omitted here.

The feed screws 21 and 22 are rotatably attached to the shaft 3 via torque limiters 5 and 6, respectively. The screw receiving portions 23 and 24 convert the rotational motion of the feed screws 21 and 22 into linear motion, and drive the specimen contact portions 1 and 2, respectively.

As shown in FIG. 4, in the ultrasonic bone density measuring device according to the second embodiment of the present invention, as with the ultrasonic bone density measuring device according to the first embodiment, the feed screws 21, The feed screws 21 and 22 rotate in conjunction with the shaft until a pressure of a certain level or more is applied to the sample 22 through the specimen contact portions 1 and 2 and the screw receiving portions 23 and 24. On the other hand, when a predetermined pressure or more is applied to the feed screws 21 and 22 via the specimen contact portions 1 and 2 and the screw receiving portions 23 and 24, the feed screws 21 and 22 start to idle with respect to the shaft 3, and the specimen The drive of the contact parts 1 and 2 is stopped.

As a result, if the torque limiters 5 and 6 are both set to the same optimum value in advance, the subject can be sandwiched by the pair of specimen contact portions 1 and 2 from both sides with equal pressure.

As described above, according to the ultrasonic bone density measuring apparatus according to the second embodiment of the present invention, the two torque limiters 5 and 6 are provided on the shaft 3, and a pair of specimens are set according to the set values of the torque limiters 5 and 6. By controlling the contact portions individually, even if the subject is not at the center position of the pair of specimen contact portions 1 and 2, the subject is moved to both sides by a single drive operation of the specimen contact portions 1 and 2. Therefore, it is possible to always hold at the same pressure.

(Embodiment 3)
Next, an ultrasonic bone density measuring apparatus according to Embodiment 3 of the present invention will be described.
The ultrasonic bone density measuring apparatus according to the third embodiment of the present invention employs a wire-pulley system as a driving mechanism for the specimen contact portion.

FIG. 5 is a diagram showing an example of the configuration of an ultrasonic bone density measuring apparatus according to Embodiment 3 of the present invention. FIG. 6 is a side view of the apparatus in which a manual dial is attached to the shaft of the ultrasonic bone density measuring apparatus shown in FIG. Note that in the ultrasonic bone density measuring apparatus according to the third embodiment of the present invention, the same components as those of the ultrasonic measuring apparatus according to the first embodiment described above are denoted by the same reference numerals, and description thereof is omitted here.

The driving body 31 includes a wire 33 wound around the pulley 37 with a constant tension and a tension adjusting mechanism 35 that adjusts the tension of the wire 31, and the specimen contact so that the specimen contact portion 1 is interlocked with the movement of the driving body 31. The part 1 is attached to the driving body 31. Similarly, the driving body 32 has a wire 34 wound around the pulley 38 with a constant tension and a tension adjusting mechanism 36 for adjusting the tension of the wire 34, and the specimen contact portion 2 is interlocked with the movement of the driving body 32. As described above, the specimen contact portion 2 is attached to the drive body 32.

The tension adjusting mechanisms 35 and 36 may be any mechanism as long as the tension of the wire can be adjusted. In addition to the tension spring as shown in the drawing, the tension adjusting mechanism 35 and 36 may be appropriately adjusted using a bolt and a nut. It is also conceivable to use a mechanism that can adjust the tension.

The pulleys 37 and 38 are fixed to the shaft 3, and the wires 33 and 34 are wound with a constant tension. Here, since the distance between the shaft 3 on which the pulley 38 is fixed and the specimen contact portion 2 is long, the driving body 32 is a substantially U-shaped continuous structure for reinforcing the strength of the driving body 32 as shown in FIG. It is said.

Next, the operation of the ultrasonic bone density measuring apparatus according to the third embodiment of the present invention will be described with reference to FIGS.
When the shaft 3 is rotated, the pulleys 37 and 38 fixed to the shaft 3 are rotated in conjunction therewith. Since the wires 33 and 34 of the driving bodies 31 and 32 are wound around the pulleys 37 and 38 with a constant tension as shown in the drawing, a frictional force is generated between the pulley 37 and the wire 33, and the pulleys 37 and 38 rotate. The specimen contact portions 1 and 2 attached to the driving bodies 31 and 32 move linearly with the movement.

At this time, if one of the specimen contact portions (here, the specimen contact portion 1) is in contact with the subject first, the repulsive force from the subject is transmitted to the driver 31 via the specimen contact portion 1. The pressure in the direction opposite to the rotation direction of the shaft 3 applied to the drive body 31 gradually increases. When the pressure applied to the driving body 31 from the subject via the specimen contact portion 1 is greater than a certain level, that is, when the pressure applied to the driving body 31 is equal to or greater than the frictional force between the pulley 37 and the wire 33 wound around the pulley 37. Further, slippage occurs between the wire 33 and the pulley 37, and the driving of the specimen contact portion 1 is stopped. Therefore, if the tension of the wire 33 is always set to the same value, the specimen contact portion 1 can be brought into contact with the subject at a constant pressure.

Further, the other specimen contact section 2 continues to move even after the one specimen contact section 1 stops. When the specimen contact portion 2 comes into contact with the subject and the pressure in the direction opposite to the rotation direction of the shaft 3 applied to the driving body 32 from the subject via the specimen contact portion 2 becomes a certain level or more, the wire 34 and the pulley A slip occurs between the two and the specimen contact portion 2 stops driving. Therefore, as described above, if the tension of the wire 34 is always set to the same value, the specimen contact portion 2 can always be brought into contact with the subject with a constant pressure.

Further, if the tensions of the two wires 33 and 34 are set to the same optimum value, the subject can be clamped from both sides with the same pressure by the pair of specimen contact portions 1 and 2 facing each other.

As described above, according to the ultrasonic bone density measuring apparatus according to the third embodiment of the present invention, the pulleys 37 and 38 that rotate in conjunction with the rotational motion of the shaft 3 and the pulleys 37 and 38 each have a constant tension. Are provided, and the pair of specimen contact portions 1 and 2 is individually controlled by adjusting the tension of the wires 33 and 34, so that the subject is positioned at the center position of the pair of specimen contact portions 1 and 2. Even if not, the subject can be clamped from both sides at the same pressure by the driving operation of the specimen contact portions 1 and 2 at a time.

In the first to third embodiments of the present invention, one mode for carrying out the present invention has been illustrated. However, the present invention is not limited to this, and the present invention is configured by using at least one drive source. Two drive mechanisms that respectively drive the contact portions, and a control portion that individually stops driving of the sample contact portions by the drive mechanisms when the pressing force on the subject exceeds a predetermined value If it is good.

The present invention enables a subject to be clamped from both sides with the same pressure by a pair of opposing specimen contact portions. Therefore, it is possible to more accurately measure the ultrasonic signal that passes through the subject.

The figure which shows an example of a structure of the ultrasonic bone density measuring apparatus by Embodiment 1 of this invention. Side view of apparatus with manual dial attached to ultrasonic bone density measuring apparatus according to embodiment 1 of the present invention The enlarged view of the shaft part of the ultrasonic bone density measuring apparatus by Embodiment 1 of this invention Explanatory drawing for demonstrating the drive mechanism of the ultrasonic bone density measuring apparatus by Embodiment 2 of this invention. The figure which shows an example of a structure of the ultrasonic bone density measuring apparatus by Embodiment 3 of this invention. Side view of apparatus with manual dial attached to ultrasonic bone density measuring apparatus according to embodiment 3 of the present invention

Explanation of symbols

1, 2 Specimen contact portion 3 Shaft 4 Manual dial 5, 6 Torque limiter 7, 8 Pinion gear 9, 10 Rack 11, 15 Nut 12, 16 Spring 13, 14, 17, 18 Sliding plate 21, 22 Lead screw 23, 24 Screw receiving portion 31, 32 Driving body 33, 34 Wire 35, 36 Tension adjusting mechanism 37, 38 Pulley

Claims (6)

An ultrasonic bone density measuring apparatus that measures a characteristic of a subject by sandwiching the subject between a pair of opposing specimen contact portions and transmitting an ultrasonic signal to the subject,
Two driving mechanisms for respectively driving the specimen contact portions by one driving source;
An ultrasonic bone density measuring apparatus, comprising: a control unit that individually stops driving of the specimen contact unit by the driving mechanism when a pressing force on the subject exceeds a predetermined value. An ultrasonic bone density measuring apparatus that measures a characteristic of a subject by sandwiching the subject between a pair of opposing specimen contact portions and transmitting an ultrasonic signal to the subject,
A rotating shaft,
Two drive mechanisms for individually driving the specimen contact portions using the rotational movement of the shaft;
An ultrasonic bone density, comprising: a control unit that individually stops driving of the specimen contact unit by the drive mechanism when a pressing force on the subject by the specimen contact unit exceeds a predetermined value. measuring device. An ultrasonic bone density measuring apparatus that measures a characteristic of a subject by sandwiching the subject between a pair of opposing specimen contact portions and transmitting an ultrasonic signal to the subject,
A rotating shaft,
Two drive mechanisms for individually driving the specimen contact portions using the rotational movement of the shaft;
Each specimen contact portion provided by the drive mechanism when the pressure in the direction opposite to the rotation of the shaft, which is provided on the same axis as the shaft and is transmitted to the drive mechanism via the specimen contact portion, exceeds a predetermined value. An ultrasonic bone density measuring device comprising two torque limiters for individually stopping the driving of the bone. In the ultrasonic bone density measuring device according to claim 3,
The two drive mechanisms are:
A pinion gear rotatably mounted on the shaft via the torque limiter,
A rack that converts the rotational motion of the pinion gear into a linear motion, and drives each of the specimen contact portions;
The torque limiter provided for each drive mechanism is
Until the pressure in the direction opposite to the rotation of the shaft transmitted to the pinion gear via the specimen contact portion and the rack becomes a predetermined value or more, the pinion gear is rotated so as to be interlocked with the rotational movement of the shaft. To drive the specimen contact portion,
An ultrasonic bone density characterized in that when the pressure in the direction opposite to the rotation of the shaft transmitted to the pinion gear exceeds a predetermined value, the pinion gear is idled to stop driving the specimen contact portion. measuring device. In the ultrasonic bone density measuring device according to claim 3,
The two drive mechanisms are:
Two feed screws rotatably attached to the shaft via the torque limiters,
Each having two screw receiving portions for converting the rotational motion of the feed screw into linear motion and driving the specimen contact portion, respectively;
The torque limiter provided for each drive mechanism is
The feed screw is rotated so as to be interlocked with the rotational movement of the shaft until the pressure in the direction opposite to the rotation of the shaft transmitted to the feed screw via the specimen contact portion and the screw receiving portion becomes a predetermined value or more. To drive the specimen contact portion,
The ultrasonic bone density characterized in that when the pressure in the direction opposite to the rotation of the shaft transmitted to the feed screw becomes a predetermined value or more, the feed screw is idled to stop the driving of the specimen contact portion. measuring device. An ultrasonic bone density measuring apparatus that measures a characteristic of a subject by sandwiching the subject between a pair of opposing specimen contact portions and transmitting an ultrasonic signal to the subject,
A shaft that rotates about an axis;
Two pulleys fixed to the shaft and rotating in conjunction with the rotational movement of the shaft;
Two wires each having a wire wound around the pulley with a constant tension and a tension adjusting mechanism for adjusting the tension of the wire, and individually driving the pair of specimen contact portions using the rotational motion of each pulley. With a driving body,
Until the pressure in the direction opposite to the rotation of the shaft transmitted to the driving body via the specimen contact portion becomes a predetermined value or more, the rotational force of the pulley is utilized by the frictional force between the pulley and the wire. Driving the specimen contact portion attached to the driver,
When the pressure in the direction opposite to the rotation of the shaft transmitted to the driving body exceeds a predetermined value, the driving of the specimen contact portion attached to the driving body is stopped by slipping between the pulley and the wire. An ultrasonic bone density measuring apparatus.

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