Ultrasonic probe for producing four dimensional image

The present invention relates to an ultrasonic probe for producing a real-time three dimensional live action image (a four dimensional image), which has a long lifetime, and an improved image quality, can prevent malfunction. The ultrasonic probe for producing a four dimensional image includes power transmission means for transmission of power from an upright motor to a module (2) having acoustic elements for swinging the module, the power transmission means includes a first link (20) having a horizontal portion (22) directly connected to a motor shaft, and a sloped portion projected upward from one side end of the horizontal portion at an angle in conformity with a locus of a swing action of the module, and a second link (21) comprising a horizontal (29) having an interlocking connected thereto and a pair of parallel portion (30) and (31) projected upwardly from opposite ends of the horizontal portion, such that the second link is interlocked along the first link in a state of being interposed between the first link and the module, wherein the interlocking shaft (28) is connected with an inclined portion of the first link by a shaft and the pair of parallel portions is mounting to a lower side of the module in a horizontal direction with a shaft.

TECHNICAL FIELD

The present invention relates to medical ultrasonic probes for producing a real-time 3 dimensional live action image (4 dimensional image), more particularly, to a medical ultrasonic probe which, not only has a simple structure and a long lifetime, but also is able to improve an image production characteristic in production of a real-time three dimensional live action image.

BACKGROUND ART

The medical ultrasonic probe, electrically connected to a system of a medical ultrasonic image diagnotor for producing an image by making a direct scanning of a human body intended to observe, is also called in general as a medical ultrasonic transducer or a medical ultrasonic probe.

In the medical ultrasonic probes which are essential elements for the medical ultrasonic image diagnotors, depending on the image the ultrasonic probe can produce, there are 2 dimensional image ultrasonic probes which can produce 2 dimensional sectional images, 3 dimensional image ultrasonic probes which can produce 3 dimensional images, and 4 dimensional image ultrasonic probes which can produce 3 dimensional real-time live action images which are in general defined as 4 dimensional images.

In the field of art the present invention is related thereto, there have been active researches and developments of 4 dimensional image ultrasonic probes which enable to make a real time observation of a live action image, such as motion of an unborn child, by a know method in which one dimensional array of acoustic elements each for making direct reception/transmission of an acoustic signal swing around a shaft of the one dimensional array, to obtain the 4 dimensional image.

As examples of known arts for producing the 4 dimensional image by the method in which the acoustic elements swing around the shaft of the one dimensional array of the acoustic elements, there are an ultrasonic probe for producing a real time three dimensional live action image (Korea Patent Registration No. 455606) in which the acoustic elements swing around the shaft of the acoustic element array by a power transmitted thereto from an upright motor through power transmission means, such as pulleys and wires, an image diagnosis sector probe (Korea Patent Registration No. 393354) in which the acoustic elements swing around the shaft of the acoustic element array by a power transmitted thereto from an upright motor through power transmission means, such as gears, and an European Patent (EP 1,208,800A2) in which the swing of a transducer is controlled by a belt that is connected between a motor shaft and a driving shaft of the transducer.

DISCLOSURE OF INVENTION

Technical Problem

However, the related art ultrasonic probes for producing a 4 dimensional image have a problem in that a structure for swinging acoustic elements around the shaft of the one dimensional array is complicate, and consequently, have many components, which impairs productivity, and leads to have a short lifetime.

Moreover, the related art ultrasonic probes for producing a 4 dimensional image have problems in that an image production characteristic, or function is poor due to a poor initial position control performance of the acoustic elements that swing.

Technical Solution

Accordingly, the present invention is directed to an ultrasonic probe for producing a 4 dimensional image, that substantially obviates one or more problems due to limitations and disadvantages of the related art.

An object of the present invention is to provide an ultrasonic probe for producing a 4 dimensional image, in which acoustic elements are made to swing around a shaft of one dimensional array of the acoustic elements by power transmitted through power transmission means, such as a link mechanism, for providing an ultrasonic probe for producing a 4 dimensional image, which has a simple structure and a small number of components to provide a good productivity and an improved lifetime.

Another object of the present invention is to provide an ultrasonic probe for producing a 4 dimensional image, which has a good initial position control performance to improve an image production performance.

To achieve these objects and other advantages and in accordance with the purpose of the invention, as embodied and broadly described herein, the ultrasonic probe for producing a four dimensional image includes power transmission means for transmission of power from an upright motor to a module having acoustic elements for swinging the module, the power transmission means includes a first link having a horizontal portion directly connected to a motor shaft, and a sloped portion projected upward from one side end of the horizontal portion at an angle in conformity with a locus of a swing action of the module, and a second link comprising a horizontal portion having an interlocking connected thereto and a pair of parallel portion projected upwardly from opposite ends of the horizontal portion, such that the second link is interlocked along the first link in a state of being interposed between the first link and the module, wherein the interlocking shaft is connected with an inclined portion of the first link by a shaft and the pair of parallel portions is mounting to a lower side of the module in a horizontal direction with a shaft.

The ultrasonic probe further includes a permanent magnet on the module and a first hall sensor and a second hall sensor mounted to predetermined points of the frame in correspondence to the permanent magnet according to a locus of a swing action of the module, wherein an initial position of the module is controlled by using an overlapped portion of signals detected by the first hall sensor and the second hall sensor.

Or alternatively, the ultrasonic probe further includes a permanent magnet on the first link and a first hall sensor and a second hall sensor mounted to predetermined points of the frame in correspondence to the permanent magnet according to a locus of a rotation of the first link, wherein an initial position of the module is controlled by using an overlapped portion of signals detected by the first hall sensor and the second hall sensor

Advantageous Effects

The ultrasonic probe for producing a four dimensional image of the present invention has advantages in that a structure thereof is simple to provide good productivity and a longer lifetime, and to permit to save a production cost, because the link mechanism which is power transmission means having simple and a small number of components transmits power from the motor to the module having acoustic elements to swing the module.

The construction of the power transmission means of a link mechanism for transmission of power from the motor to the module permits an accurate control of the swing action because almost no temporal error of driving and no positional error (gap) takes place, which is likely to take place between driving of a motor and the swing action of the module.

The good initial module position control performance improves a quality of the image, and prevents malfunction of the swing action of the module.

BEST MODE FOR CARRYING OUT THE INVENTION

FIG. 1illustrates a perspective view of an ultrasonic probe for producing a 4 dimensional image in accordance with a preferred embodiment of the present invention having a housing (not shown) thereof removed therefrom, andFIG. 2illustrates a perspective view of the ultrasonic probe for producing a 4 dimensional image inFIG. 1having a frame3thereof removed therefrom additionally for showing the probe in more detail, in which a module2has swung, slightly.

FIG. 3illustrates a section of key parts of the ultrasonic probe for producing a 4 dimensional image inFIG. 1having the housing (not shown) thereof removed therefrom, andFIG. 4illustrates an exploded perspective view of the ultrasonic probe for producing a 4 dimensional image inFIG. 1having the housing (not shown) thereof removed therefrom.

Referring toFIGS. 1 to 4, the ultrasonic probe for producing a 4 dimensional image includes a module2having acoustic elements for transmission/reception of an ultrasonic wave and a link mechanism20and21which is power transmission means mounted on the frame3, a motor4under the frame3for generating power to swing the module2, having an upright shaft (not shown) for reducing an entire size of the probe.

Units of the ultrasonic probe for producing a 4 dimensional image of the present invention will be described.

The motor4, a power generating source, is mounted on an underside of the frame3with fastening means, such as flange5and bolts26a, for generating power to swing the module2having acoustic elements which make direct reception/transmission of an ultrasonic wave around a shaft of one dimensional array of the acoustic elements.

The motor4is a step motor electrically connected to a motor driver (not shown) in a system (not shown) of a medial ultrasonic image diagnotor, for making regular/reverse direction rotation and stepping rotation in response to an electric signal from the motor driver, in which the module2makes stepping rotation according to stepping rotation of the motor shaft (not shown).

Over the motor4, there is speed reduction means6, such as an assembly of a planetary gear train, for speed reduction and transmission of the rotation of the motor shaft (not shown) to the module2. Transmitting the rotation of the motor shaft (not shown) to the module2at a speed reduced according to a reduction ratio of the reduction means6, to enable the module2to swing at smaller steps, the speed reduction means6can provide a good quality image owing to the smaller steps.

The speed reduction means6may not be employed depending on a stepping control performance of the motor driver (not shown) and the motor4, and the speed reduction means is not limited to the assembly of the planetary gear train, but may be other speed reduction means as far as the means is substitutional.

Refer to the ultrasonic probe for producing a real time three dimensional live action image disclosed in Korea Patent Registration No. 455606 for details of the assembly of the planetary gear train.

The motor4and the reduction means6may be fabricated as one unit, or detachable so as to fasten with screws, and is not limited to only one type.

On the reduction means6, there is a flange5fastened to the reduction means6with screws or the like for joining the motor4and the reduction means6to the frame3. The flange6is also joined to the frame3at an underside thereof with screws or the like.

The joining method of the motor4and the reduction means6to the flange5, and the joining method of the flange to the frame3are not limited to above screw joining, but other joining methods may be applied thereto as far as the methods are within a range of variation/modification or substitutional of above joining method.

Though the frame3has an oval section substantially, since it is adequate if the frame3has a shape in conformity with a locus of the swing of the module2like a shape of the module2, the shape of the frame3is not necessarily limited to the oval shape.

The frame3includes a shaft hole8in a bottom for rotatable pass through of a rotation shaft7which is an output side of the reduction means6, and upward projections9and10at opposite sides for mounting the module2on a shaft so as to swing around the shaft.

As another embodiment of the present invention, in a case no reduction means is employed, a motor shaft (not shown) of the motor4is rotatably passed through the shaft hole8in the bottom of the frame3.

Of course, a profile of the frame3may be changed depending, not only on the shape of the module2and the locus of swing of the module2, but also on a design of the housing (not shown).

The module2of the ultrasonic probes for producing a four dimensional image of the embodiment includes a piezo electricity ceramic (not shown), a matching layer (not shown), a backing (not shown), a lens2b, and so on housed in a module housing2a, a link mechanism20and21, which is a power transmission means and will be described later, mounted on a shaft on a lower side of the housing2ain a horizontal direction, and opposite sides of the module housing2amounted on the frame3with shafts so as to be able to swing around the shafts.

It is adequate as far as the module2is mounted on the frame3with the shafts so as to be able to swing around the shafts by power from the motor4. Mounting methods of the module2and the frame3with the shafts are not limited to a particular design.

The module housing2ahas downward projections11and12from opposite sides with shaft holes13and14formed therein with bearings15and16mounted therein respectively. There are shafts17and18are mounted on the bearings15and16respectively, for swinging the module2.

At first, the piezo electricity ceramic (not shown), the matching layer (not shown), and the backing (not shown) are placed in the module housing2ain a state the piezo electricity ceramic (not shown), the matching layer (not shown), and the backing (not shown) are bonded together. Then, a lens material is molded to form the lens2bas one body with the module housing2a.

A method for fabricating the module2is not limited to above method in which a lens material is molded to form the lens2bas one body with the module housing2a, but a method is viable in which the piezo electricity ceramic (not shown), the matching layer (not shown), and the backing (not shown) and the lens2bare placed in the module housing2ain a state the piezo electricity ceramic (not shown), the matching layer (not shown), and the backing (not shown) are bonded together and the lens2bis formed. Thus, it is not necessary to limit the method for fabricating the module2to a particular method or system.

In general, elements of the module2, i.e., the piezo electricity ceramic (not shown), the matching layer (not shown), and the backing (not shown), the lens2b, electric lines19, and so on are not limited to above in the field of the art, but removal of some of the elements, or substitution with other elements is still within a scope of the present invention as far as the module2is within a range that meets functions for converting an acoustic signal to an electric signal, and vice versa, and transmitting/receiving an ultrasonic signal.

It is adequate that the electric lines19are connected to the acoustic elements so that the piezo electricity ceramic (not shown) is driven by an electric signal to generate an acoustic signal, or meets a function of sensing the piezo electricity ceramic (not shown) driven by the acoustic signal. The electric lines19may be one selected from wire cable, flexible or hard type printed circuit board, flexible flat cable, and so on, or a combination of some of above, but are not limited, specifically.

The electric lines19are lead through an electric line opening2cat a lower side of the module housing2a, between the module housing2aand the frame3, and an electric line opening3aat a lower side of the frame3, and connected to an ultrasonic image diagnotor system (not shown).

4. Link Mechanism

The link mechanism, which is power transmission means of the ultrasonic probe for producing a four dimensional image includes a first link20directly connected to the rotation shaft7, and a second link21between the first link20and the module housing2a.

The first link20includes a horizontal portion22inserted on the rotation shaft7, and a sloped portion23sloped upward from one side end of the horizontal portion22at a predetermined angle q having the second link21mounted thereon with a shaft so as to interlock the sloped portion23with the second link21.

The horizontal portion22of the first link20has a shaft hole51for placing the rotation shaft7therein, a cut away portion25having a portion cut away therefrom for easy mounting of the rotation shaft to the shaft hole51, and a bolt26for fastening the cut away portion25to make connection between the shaft hole51and the rotation shaft7rigid after the rotation shaft7is placed in the shaft hole51.

It is not necessary to limit the rigid connection between the first link20and the rotation shaft8to the use of the bolt.

The sloped portion23of the first link20has a shaft hole27for mounting the second link21with a shaft to interlock the sloped portion23with the second link21, and is sloped at 135° from the horizontal portion22. However, the angle between the horizontal portion22and the sloped portion23is not limited to this, but may vary according to a size of the locus of the swing of the module2.

The second link21includes a horizontal portion29for connection to an interlocking shaft28for mounting the first link20with the shaft, and one pair of parallel portions30and31projected upward from opposite sides of the horizontal portion29for mounting to the module housing2aperpendicular to an underside of the module housing2awith shafts.

The horizontal portion29of the second link21has a shat hole27for connection to the interlocking shaft28, preferably with a bearing therein for rotation of the interlocking shaft28, but of course not limited thereto.

The module housing2aincludes a downward projection33having a shaft hole34, and each of the parallel portions30and31of the second link mechanism21has a shaft hole35or36with a bearing37or38therein, wherein the downward projection33and the parallel portions30and31are coupled with shafts39and40passed through the shaft holes35and36and placed in the shaft hole34, with bearings37and38between the shaft holes35and36and shafts39and40respectively, but of course not limited thereto.

In the case no reduction means6is employed, the motor shaft (not shown) is placed in the shaft hole51in the horizontal portion22of the first link20in press fit.

Because a rotation power of the motor4is transmitted to the module2as it is without temporal and positional errors (a gap) through the plurality of links20and21, which is power transmission means, the swing of the module2is controlled precisely.

That is, since rotation power transmission from the motor4to the module2is made directly by the links20, and21, preventing an error of a swing time period caused by slip between the pulley and the wire in the power transmission or an assembly error (a gap) between the pulley and the wire from taking place, the precise control of the module2can be made.

Particularly, as described before, in the present invention, the rotation power of the motor4can be transmitted to the module2precisely by using the links20and21, and furthermore, the swing of the module2can be controlled more precisely as the links20and21are arranged in three dimension at predetermined angles from the rotation shaft of the motor4, resulting to have acceleration/deceleration periods according to a locus of swing of the module2.

That is, because the first link20sloped at a predetermined angle varies an angle of the rotation shaft of the motor4, and the second link21connected to the first link20in a state sloped at a predetermined angle is mounted to the module4with a shaft, arranging the links20and21three dimensionally and making rotation directions of the first link20and the second link21opposite, between a rotation angle of the rotation shaft of the motor4and a swing angle of the module2, there is not a linear function, but a unique function having acceleration/deceleration periods.

FIG. 7illustrates a side view of the rotation shaft of the motor rotated at a predetermined angle qm, andFIG. 8illustrates a plan view ofFIG. 7.

Referring toFIGS. 7 and 8, if it is assumed that the sloped portion of the first link20has a 45 of slope angle qi, L1=L0sinqm, and tanqmL1/h0. Since the links rotate in opposite directions, between the swing angle qmof the module and the rotation angle qmof the rotation shaft of the motor4, there is a relation of a trigonometric function of qM=−tan−1(L0/h0)*sinqm.

FIG. 9illustrates a graph showing above trigonometric function, wherefrom it can be noted that, between the swing angle qMof the module2and the rotation angle qmof the rotation shaft of the motor4, there is a relation of a sin function established. That is, in view of a characteristic of the sin function, at a starting and an end of the swing locus, decelerations are made, and in the middle of the swing locus, an acceleration is made.

Accordingly, at the starting and end of the swing action of the module, the swing action is smooth and precise owing to the deceleration, enabling to control the swing action of the module more precisely.

Since the acceleration/deceleration periods of the module vary with the angle between the horizontal portion22and the sloped portion23of the first link20, the acceleration/deceleration periods can be adjusted freely as the user desires by varying the angle between the horizontal portion22and the sloped portion23.

5. Hall Sensor and Permanent Magnet

FIG. 5illustrates a diagram showing hall sensors41and42and a permanent magnet43mounted in the ultrasonic probe for producing a four dimensional image inFIG. 1, andFIG. 6illustrates signal waveforms of the ultrasonic probe for producing a four dimensional image inFIG. 1showing a timing of detection of positional signal of the hall sensors41and42, showing a waveform of a signal S sensed/detected when the permanent magnet43on the module2approaches to the one pair of the hall sensors41and42respectively mounted at the opposite upward projections10of the frame3following the swing of the module2, wherein t denotes a time axis.

The permanent magnet43is mounted at a predetermined point of one side of the module housing2awhich is to swing, and the one pair of the hall sensors, i.e., the first hall sensor41and the second hall sensor42are mounted at sides of the frame3, for an example, predetermined points of the upward projections10, corresponding to the point where the permanent magnet41is mounted.

The hall sensors41and42are mounted at opposite sides of a centerline of the swing action of the module2close to the permanent magnet within a range in which the hall sensors41and42sense the permanent magnet wrongly, of course depending on a size of swing action of the module2and/or a signal detection performance of the hall sensors41and42.

Referring toFIG. 3, between each of the upward projections9and10of the frame3and the module2, there is a gap44for preventing the upward projections9and10of the frame3and the module2from being in contact (mechanical interference), thereby the swinging module2being not in contact or interfere with the upward projections9and10of the frame3.

Referring toFIG. 6, an initial position of the module2is sensed by using an overlapped portion P of the signals sensed/detected by the first hall sensor41and the second hall sensor42, for making a more accurate control of the initial position of the module2and preventing the module2from making a wrong swing action.

As an alternative, the permanent magnet43may be mounted to the first link20at a predetermined point, and the one pair of hall sensors, i.e., the first hall sensor41and the second hall sensor42, may be mounted at predetermined points of sides of the frame3corresponding to the point where the permanent magnet41is mounted.

Other than above elements, though the ultrasonic probe also includes acoustic fluid (not shown) for transmission of an acoustic signal between the acoustic elements and the human body, a cover case (not shown) for enabling the swing action of the module2and sealing the acoustic fluid (not shown), the housing (not shown) inclusive of a handle case (not shown) serving as a hand grip, detailed description of which will be omitted as those are not only known, but also not required to be specific.

The ultrasonic probe for producing a four dimensional image of the present invention is electrically connected to a system (not shown) of a medical ultrasonic image diagnotor, so that the motor4makes a regular/reverse direction rotation and a stepping rotation in response to a control signal from a motor driver (not shown), for transmission of the power from the motor4to the link mechanism20and21and the module2through the rotation shaft7after a speed is reduced by the reduction means6.

Eventually, the module2enables to obtain a four dimensional image (a real time three dimensional live action image) while the module2is swinging around the shaft of the one dimensional array of the acoustic elements.

Since the power is transmitted from the motor4to the module2by power transmission means having simple and small number of components, such as the first link20directly connected to the rotation shaft7, and the second link20connected to the first link20with the interlocking shaft28and to the module housing2awith a shaft, the ultrasonic probe for producing a four dimensional image of the present invention, not only has a good productivity and a long lifetime, but also saves a production cost.

INDUSTRIAL APPLICABILITY

The ultrasonic probe for producing a four dimensional image of the present invention has a significantly high industrial applicability owing to the design of the swing action of the module made by a link mechanism of a power transmission means having simple and small number of components to have a simple structure, which provides good productivity and a long lifetime, and an accurate control of the swing action without malfunction of the module to improve a quality of the image produced.