JPH0347244A - Ultrasonic probe - Google Patents

Abstract

PURPOSE:To decrease an ultrasonic damping factor and to attempt to make an outer diameter small by forming a sheath part performing an ultrasonic transmitting and recieving thinner in thickness than other sheath parts. CONSTITUTION:A sheath 23 is made thin in thickness at a part near by an ultrasonic vibrator 1 to form a sound window 3a and a part 3b corresponding to a drive transmission part 4 is made thick in thickness. These parts 3a and 3b are monolithically molded to form a sheath 3, and a case 10 is formed continuously with the sheath 3 and the drive transmission part 4 is extended in the case 10 and is connected with a gear 6a and furthermore a slip ring 7. In addition, the gear 6a is intermeshed with a gear 6b connected with a motor 8 to transmit a power of the motor 8 to the drive transmission part 4. By forming monolithically the sound window 3a and other parts of the sheath 3 like this, a connecting part becomes unnecessary and it is possible to attempt to make the outer diameter small. In addition, as only the part of the sound window 3a is thin in thickness, an ultrasonic damping factor is decreased.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an ultrasonic probe that emits an ultrasonic beam to an object to be examined and obtains an ultrasonic tomographic image.

[Conventional technology]

2. Description of the Related Art Ultrasonic diagnostic apparatuses are well known that emit an ultrasound beam to a subject to be examined, such as a living body, receive reflected waves caused by differences in acoustic impedance within the living body, and display a desired tomographic image of the inside of the living body.

Methods for scanning this ultrasonic beam can be roughly divided into mechanical scanning methods and electronic scanning methods. The former is a method in which the ultrasonic transducer is rotated or moved forward and backward in a straight line. When an ultrasonic beam is emitted to the outside in this mechanical scanning method, the area around the ultrasonic transducer is filled with an acoustic propagation material, and the ultrasonic beam is transmitted and received through an acoustic window.

FIGS. 10 and 11 show a conventional ultrasonic probe, in which the sheath 60 of the ultrasonic probe is entirely used as an acoustic window, and ultrasonic beams are transmitted and received by excitation of an ultrasonic transducer 61. .

On the other hand, unlike these conventional examples, there is also one in which the sheath and the acoustic window are provided separately. In either case, the acoustic window material must have an acoustic impedance as close as possible to that of a living body, the acoustic propagation loss that causes a decrease in sensitivity to be as small as possible, an electrical insulator to prevent electric shock, and ultrasonic It is inert to propagation media, living organisms, disinfectants, chemicals, etc.

[Problem to be solved by the invention]

Ultrasonic probes are required to have a thin outer diameter in order to reduce pain to the subject being examined. However, with a sheath that uses the entire sheath as an acoustic window, the thickness of the entire sheath must be made thinner, and the sheath cannot maintain its strength and easily breaks, and if it breaks, the metal drive transmission part inside the sheath may be damaged. There is a problem with it being exposed inside the body and involving tissues such as blood vessels.

In addition, when the acoustic window and sheath are separated, the outer diameter becomes large at the connection between the acoustic window and the sheath, and in addition to the above-mentioned problem, there is a problem that it is difficult to pass the endoscope through a channel, etc. Furthermore, when assembling the ultrasonic probe, processes such as system tying are required to prevent separation of the acoustic window and sheath, resulting in poor production efficiency.

The present invention is proposed to solve the above problems,
The aim is to provide an ultrasonic probe with an integrated acoustic window and sheath, which has sufficient strength to increase the transmission efficiency of the ultrasonic beam while reducing the diameter of the probe, and further improves production efficiency. It is something.

[Means and effects for solving the problem] In order to achieve the above object, the present invention provides an ultrasonic transducer near the tip,
In an ultrasonic probe in which the probe outer skin is integrally formed with a sheath, at least the sheath portion that transmits and receives ultrasonic waves is formed thinner than the other sheath portions.

In this way, the thickness of the part of the sheath corresponding to the transmitting and receiving surface of the ultrasonic beam is thinner than other parts, so the ultrasonic attenuation rate can be reduced, and since there are no connecting parts, the outer diameter can be made smaller. I can figure it out.

(Embodiment) FIG. 1 shows a first embodiment of the present invention, and shows a radially driven ultrasonic probe.

The sheath 3 holding the ultrasonic transducer 1 and the drive transmission section 4 is
Extends integrally. An ultrasonic transducer 1 having a lens 2 is provided at the tip of this sheath 3, and an ultrasonic propagation member 5 is enclosed around the ultrasonic transducer 1. The sheath 3 is the ultrasonic transducer 1
The wall thickness of a portion near the is made thinner to form an acoustic window portion 3a, and the wall thickness of a portion 3b corresponding to the drive transmission portion 4 is thickened. These parts 3a and 3b are integrally molded to form the sheath 3. A case 10 is provided continuously to the sheath 3, and the drive transmission section 4 extends into the case 10 and connects the gear 6a and the slip ring 7. The gear 6a meshes with a gear 6b connected to the motor 8 to transmit the power of the motor 8 to the drive transmission section 4. An encoder 9 is mechanically connected to the motor 8 to detect the rotation angle. In addition, slip ring 7
, encoder 9, and motor 8, signal cables 11 (Sig), 12 (En), and 13 (Mo) are led out and extended to an observation device (not shown), respectively. Further, the sheath 3 may be made of an appropriate material such as Teflon.

Next, the operation of this embodiment will be explained. When voltage is applied via the signal cable (MoO2) by the ultrasonic observation device, the motor 8 rotates, which rotates the gear 6b and transmits rotational force to the gear 6a. Ultrasonic transducer 1 via drive transmission section 4
Rotate.

As the motor 8 rotates, an (En) signal indicating the rotation angle of the motor 8 is output from the encoder 9 to the ultrasonic observation device via the signal cable 12. In synchronization with this (En) signal, a drive pulse is sent from the ultrasonic observation device to the signal cable (S
ig) A voltage is applied to the ultrasonic transducer 1 through a signal cable which is output through the signal cable 11, relayed by the slip ring 7, and provided inside the drive transmission section 4, and is excited. Then, the ultrasonic beam passes through the lens 2, passes through the ultrasonic propagation member 5, and is radiated to the outside through the acoustic window 3a.

The echo reflected from the object to be examined passes through the acoustic window section 3a, passes through the ultrasound propagation member 5, passes through the lens 2, and is reflected back to the ultrasound transducer 1. Here, the echo is converted into voltage, relayed to the slip ring 7 via the signal cable in the drive transmission section 4, and output from the signal cable (Stg) 11 to the ultrasonic observation device. By repeating these operations, the tomographic image of the subject is displayed as an image.

In this embodiment configured as described above, as shown in the comparison diagram shown in FIG. 2, the ultrasonic beam is
However, since a part of the sheath 3 is formed as a thin acoustic window 3a, the attenuation of the ultrasonic beam is reduced as shown in Figure B. On the other hand, the portions of the sheath 3 other than the acoustic window portion 3a have the same sheath thickness as the conventional one, so there is no problem in terms of strength. Further, since there is no connecting part between the acoustic window part 3a and the other part 3b of the sheath 3, the outer diameter can be made thinner, and there is no problem in insertion even when used endoscopically. In this example,
The ultrasonic transducer 1 is not limited to radial drive, and may be moved forward and backward in the 3-axis direction of the sheath.

FIG. 3 shows a second embodiment of the present invention, in which parts corresponding to those in the first embodiment are given the same reference numerals (the same applies to the following embodiments).

In this embodiment, the thick portion 3b of the sheath 3 is formed not only on the hand operation side of the acoustic window portion 3a but also on the tip. By forming it in this way, in addition to the effect of the first embodiment, the tip of the sheath 3 is made thicker, so that the ultrasonic probe is prevented from hitting a hard object or being pinched by a hard part when inserting it. Even if there is, it can prevent the tip from being deformed or damaged. At the same time, insertability is also improved.

FIG. 4 shows a third embodiment of the present invention, and shows a linearly driven ultrasonic probe.

Figure A is a longitudinal cross-sectional view, and Figure B is a cross-sectional view taken along line XX in Figure A.

In this embodiment, only the portion of the sheath 3 through which the ultrasonic transducer 1 passes when linearly driven is made thin. Since the ultrasonic beam is emitted only from this thin acoustic window section 3a, there is no need to make the other parts thinner.

By doing so, the strength of the portion in the circumferential direction of the sheath where the acoustic window 3a is formed can be maintained. Other configurations and effects are the same as those of the above embodiments.

The fifth example shows the fourth embodiment of the present invention, which is the tip of an ultrasonic probe, in which a housing 15 is connected to the tip of a flexible shaft 14 through which a signal cable 11 is inserted, and a recess in the housing 15 is shown. The ultrasonic transducer 1 is adhesively fixed to the holder. A sliding ring 16 made of Teflon is attached to the outer periphery of the tip of the flexible shaft 14, and the housing 15 can be rotated in the direction of the outer periphery of the flexible shaft 14 by a sliding ring receiver 17 made of stainless steel that is press-fitted and fixed to the rear end of the acoustic window section 3a. I support it. Further, a light frame 18 is adhesively fixed to the tip of the acoustic window portion 3a, and a tip screw 20 is screwed in through an O-ring 19, thereby making the tip of the sheath in a sealed state.

FIG. 6A shows the rear end side of the ultrasonic probe 56 shown in FIG. 5, and FIG. 6A is a sectional view taken along the line AA in FIG. The rear end of the sheath 3 is thermally formed into a thinner wall and fixed via a sheath fixing 25 and a retaining ring 24 to form a sheath unit. The other end of the signal cable 11 is connected to a coaxial connector 22 via a board 21.

Further, a base 23 is fixed to the other end of the flexible shaft 14. A slide shaft 27 is provided on the outer periphery of the rear end of the base 23, and a bearing 26 attached to the outer periphery of the rear portion of the slide shaft 27 is fixed so as to be sandwiched between a BE shaft 28.

A board 21 is fixed to the rear end of the BE shaft 28, and a connector stand 30 equipped with a coaxial connector 22 and a rotation pin 29 is connected to the BE shaft 28.
8 with screws, a rotation transmission unit that moves integrally from the flexible shaft 14 to the connector stand 30 is formed.

Next, with respect to the base 31 provided on the outer periphery of the slide shaft 27,
The sheath unit is fixed with screws, and the rotation transmission unit is fixed with a BE ring 32. Furthermore, a guard 33 for preventing bending is screwed to the sheath unit side, and a side hole 34 formed at the rear of the sheath unit is closed with a rubber stopper 35. This side hole 34 is for suctioning the ultrasonic wave propagating member 5. Remove the tip screw 20, immerse the tip of the ultrasonic probe into the ultrasonic wave transmitting member 5, and suck it with a suction device attached via a jig. Then, the inside of the sheath 3 is pulled under pressure and filled with the ultrasonic transmission member 5.

Furthermore, a gripping member 36 is fixed to the outside of the base 31 with screws, and a C ring 37 and an index pin 38 are fitted into the gripping member 36. Note that O-rings 39 to 42 are provided at required locations of the ultrasonic probe to hold the ultrasonic propagation member 5, which is filled from the sys unit to the inside of the base 31, in a liquid-tight manner.

According to this embodiment configured in this manner, when a signal is supplied from the coaxial connector 22, it is transmitted to the ultrasonic transducer 1 via the signal cable 1 and is driven to transmit and receive ultrasonic waves. That is, the ultrasound is emitted from the ultrasound transducer 1, passes through the ultrasound propagation member 5 and the acoustic window 3a, and reaches the lumen wall of the living body, and the reflected waves from there are reflected from the ultrasound transducer 1. It is received at

In this case, since the acoustic window 3a of the sheath 3 is formed with a thin wall thickness, it is possible to suppress attenuation to a low level even when ultrasonic waves pass through, and the reflected waves are processed into signals and displayed as images on the monitor of the observation device. It can be projected clearly even when In addition, since the acoustic window 3a is formed integrally with the sheath 3, there is no unevenness on the outer periphery, so when it is inserted into a forceps channel of an endoscope or inserted into a living body, there is no possibility of damaging the sheath itself or the living body. can be avoided.

In addition, the ultrasonic transducer 1, which is fixed to the housing 15 at the tip of the ultrasonic probe, is smoothly rotated by the housing 15, together with the flexible shaft 14, in the outer circumferential direction of the sheath 3 via the sliding ring 16 and the sliding ring receiver 17. The sheath 3 can be rotated to transmit and receive ultrasonic waves over almost the entire circumference of the sheath 3, thereby obtaining an ultrasonic image without uneven rotation.

In addition, at the rear end of the ultrasound probe, a slider 43 is fixed to the base 23 that is integrated with the flexible shaft 14 with screws.
However, since the cutout part of the slider shaft 27 is movable by rubbing in the axial direction, even if the probe insertion part is bent to a small curvature, the flexible shaft 14 is fixed even though the housing 15 is fixed in the axial direction. Can escape backwards in the axial direction. Therefore, the rotational force of the flexible shaft 14 can be transmitted without applying a load in the axial direction.

FIG. 7 is an enlarged cross-sectional view of the vicinity of the connection part of the operation part 44 on the proximal side of the ultrasound probe. Fix the joint A46 with a screw to the rotary output shaft 45 connected to a motor (not shown),
A coaxial connector 848 to which the signal line 47 inserted through the rotary output shaft 45 is connected is screwed to the joint A46.

Further, the joint B49 is screwed to the joint A46 so that both rotate integrally.

A groove 50 is formed at the front end of the joint B46, and six grooves 51 are formed in the outer circumferential direction at the rear of the groove 5°.

Further, the operating section 44 is provided with a chassis 52, and in front of the chassis 52, a fixing member 53 is provided via a stopper 54 so as to cover a joint A46 and a joint B49, and to be coaxial with these. . In addition, the fixing member 5
3 has a groove 55 formed therein for receiving the C-ring 37 of the gripping member 36.

With this configuration, the ultrasonic probe 56 is connected to the operating section 44 so that the rotation axes of both are coaxial. The mechanical connection is made using joint B on the operating section 44 side.
This is done by fitting the notch 51 of 49 with the rotation pin 29 on the probe side. In this case, the rotation pin 29 can be reliably fitted into the notch 51 by being guided by the groove 50 formed continuously with the notch 51 .

On the other hand, electrical connection is made by connecting the coaxial connector A22 on the probe side and the coaxial connector 848 on the operating section 44 side. To fix the ultrasonic probe 56 and the operating section 44, attach the C ring 37 of the ultrasonic probe 56 to the operating section 4.
The receiver formed on the fixing member 53 on the fourth side is fitted into the groove 55 while being elastically deformed.

As described above, according to this embodiment, when attaching and detaching the probe and the connecting portion, the mechanical connection, that is, the rotation transmission, can be reliably and easily performed, and the electrical connection can also be reliably performed.

FIG. 8 shows a system in which an ultrasonic probe 56 is connected to an operating section 44 supported by an arm 57. 58 is an ultrasonic observation device.

FIG. 9 shows the ultrasonic probe of each of the above embodiments
This figure shows how it is inserted into the channel and used endoscopically. To display an ultrasound image, the ultrasound observation device 58 processes the echoes and displays them on a monitor.

〔Effect of the invention〕

(According to the present invention, the acoustic window and other parts of the sheath are integrally formed, so there is no need for a connecting part, and the outer diameter can be reduced. In addition, only the acoustic window part is thinned. Since the thickness is thin, the ultrasonic attenuation rate is reduced.The other sheath parts have sufficient wall thickness, so there are no problems with the strength of the ultrasonic probe and safe ultrasonic diagnosis can be achieved. By making the probe smaller in diameter, it is possible to reduce pain for the patient, and it can also be inserted smoothly into the channel of the endoscope.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram showing a first embodiment of the present invention, FIG. 2 is an explanatory diagram comparing the same embodiment with a conventional example, and FIG. 3 is a partial diagram showing a second embodiment of the present invention. 4A and 4B are partial sectional views and XX sectional views showing a third embodiment of the present invention, and FIGS. 5 to 7 are partial sectional views showing a fourth embodiment of the present invention. FIG. 8 is an overall view of the ultrasonic diagnostic apparatus; FIG. 9 is an explanatory diagram of the state in which the ultrasonic probe of the present invention is used; FIGS. 1O and 11 show conventional examples. It is something that ■... Ultrasonic transducer 3... Sheath 3a...
Sound C window section 4... Drive transmission section Fig. 3 Fig. 4 Fig. 9

Claims (1)

[Claims] 1. In an ultrasonic probe in which an ultrasonic transducer is provided near the tip and the probe outer skin is integrally formed with a sheath, at least the sheath portion that transmits and receives ultrasonic waves is thinner than the other sheath portions. An ultrasonic probe characterized by a thick wall.