JP4674426B2 - Ultrasonic probe - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an ultrasonic probe used as, for example, a body cavity insertion type ultrasonic diagnostic apparatus.
[0002]
[Prior art]
As an intra-body-cavity type ultrasonic diagnostic apparatus equipped with an ultrasonic probe that is inserted into a body cavity using an endoscope or the like as a guide means, for example, the configuration shown in FIG. 5 has been widely used. Yes.
[0003]
In the figure, reference numeral 1 denotes an endoscope. The endoscope 1 is formed by connecting an insertion portion 3 into a body cavity to a main body operation portion 2, and a distal end portion of the insertion portion 3 is well known. As described above, an endoscope observation means including an illumination window and an observation window is attached. A treatment tool insertion channel 4 for inserting forceps and other treatment tools is provided in a portion from the main body operation unit 2 to the distal end of the insertion unit 3. The distal end of the treatment tool insertion channel 4 is illuminated. It opens as a treatment instrument outlet in the vicinity of a part where a window, an observation window and the like are provided.
[0004]
Reference numeral 10 denotes an ultrasonic probe. The ultrasonic probe 10 has a probe main body 11 and a scanning unit 12 made of an elongated member having a small diameter, and the proximal end portion of the probe main body 11 is detachable from the scanning unit 12. To be connected. The scanning unit 12 is attached to an arm 16 connected to a rack 15 on which the ultrasonic observation apparatus 13 and its monitor 14 are mounted. A cord 17 extends from the scanning unit 12, and the cord 17 is detachably connected to the ultrasonic observation device 13 installed in the rack 15. The scanning unit may be configured to be attached to the main body operation unit 2 of the endoscope 1.
[0005]
FIG. 6 shows a cross section of the distal end portion of the probe main body 11. The probe main body 11 has a flexible sleeve 20 formed of a resin tube having good electrical insulation and flexibility in the bending direction. At the tip of the flexible sleeve 20, acoustic characteristics are obtained. A tip cap 21 made of a member having excellent shape retention is connected and provided. Here, the tip cap 21 has a larger diameter than the flexible sleeve 20. Accordingly, the treatment instrument insertion channel 4 of the endoscope 1 is mounted so as to be inserted from the distal end side of the insertion portion 3 toward the main body operation portion 2.
[0006]
The tip cap 21 has a structure in which the tip is closed, and an ultrasonic transducer 22 is provided in the tip cap 21. The ultrasonic transducer 22 is a rotary ultrasonic probe that scans in the rotational direction. The ultrasonic transducer 22 is rotationally driven by a driving unit such as a motor provided in the scanning unit 12. For this purpose, a flexible shaft 23 extending from the scanning unit 12 through the flexible sleeve 20 and into the tip cap 21 is provided. Here, the flexible shaft 23 is formed of, for example, a close coil made of a metal wire. The ultrasonic transducer 22 is mounted on a substrate 24, and the distal end portion of the flexible shaft 23 is connected to a cylindrical body 25 that is connected to the substrate 24. The flexible shaft 23 is a hollow member formed by winding a metal wire in a closely wound spiral shape. The scanning unit 12 is equipped with an encoder for detecting the rotation angle of the ultrasonic transducer 22 in addition to the above-described driving means such as a motor. The internal configuration of the scanning unit 12 is conventionally well known. Therefore, illustration and description thereof are omitted.
[0007]
A driving pulse is transmitted from the ultrasonic observation device 13 to the ultrasonic transducer 22, and ultrasonic waves are transmitted toward the body based on the driving pulse. In addition, the reflected echo from the body tissue tomographic part is received and converted into an electrical signal, and this electrical signal is transmitted to the ultrasonic observation apparatus 13 and subjected to predetermined signal processing. Accordingly, a coaxial cable 26 is connected to the ultrasonic transducer 22, and the coaxial cable 26 is inserted into the flexible shaft 23 from the cylindrical body 25 connected to the substrate 24 and is attached to and detached from the scanning unit 12. It extends to a connector 27 (see FIG. 5) that can be connected. As shown in FIG. 7 as an equivalent circuit, a coil 28 is provided between the wirings 26a and 26b at a position near the connection portion of the coaxial cable 26 to the ultrasonic transducer 22. The coil 28 is attached to the substrate 24 together with the ultrasonic transducer 22.
[0008]
In mounting the coil 28 on the substrate 24, if the coil 28 is disposed at a position on the near side of the substrate 24, the length of the tip cap 21 becomes long. Since the distal end cap 21 is a hard member, when the distal end cap 21 is elongated, the operability for insertion into the body cavity is hindered. From the above, in the prior art, as shown in FIG. 6, the coil 28 is attached to the back side of the substrate 24, that is, the side opposite to the side where the ultrasonic transducer 22 is mounted. Is used. For this purpose, a through hole 24a is formed in the connecting portion of the substrate 24 to the cylinder 25, and the coaxial cable 26 from the cylinder 25 extends from the front surface side of the substrate 24 to the back surface side through the through hole 24a. I am doing so.
[0009]
Here, the ultrasonic transducer 22 includes a piezoelectric element 22a having at least a predetermined width and thickness, an acoustic matching layer 22b laminated on the ultrasonic transmission / reception surface side, and a backing material laminated on the opposite surface. It is comprised from the laminated body with 22c. Further, an acoustic lens or the like is laminated on the ultrasonic wave transmission / reception surface as necessary. A backing material 22 c is fixed to the substrate 24 by means such as adhesion, and the ultrasonic transducer 22 is mounted on the substrate 24.
[0010]
Electrodes 29a and 29b are respectively formed on the front and back surfaces of the piezoelectric element 22a, and wirings 30a and 30b are connected to these electrodes 29a and 29b. As shown in FIG. 8, electrode patterns 31 a and 31 b to which the terminals of the coil 28 are connected are formed on the back surface of the substrate 24, and the electrode patterns 31 a and 31 b on the substrate 24 are formed on the formation portions. Through holes 32a and 32b are formed. Wirings 30a and 30b extending from both surfaces of the piezoelectric element 22a are led to the back side of the substrate 24 through these through holes 32a and 32b, and connected to the electrode patterns 31a and 31b by means of soldering or the like. Thus, it is electrically connected to the coil 28. Also, the wirings 26a and 26b led out from the coaxial cable 26 passing through the cylindrical body 25 from the flexible shaft 23 are also connected to the electrode patterns 31a and 31b by means such as soldering.
[0011]
[Problems to be solved by the invention]
By the way, in the tip cap 21, it is desirable that the transmission / reception surface of the ultrasonic transducer 22 be arranged on a plane including the axis of the tip cap 21. From the thickness dimension of the ultrasonic transducer 22 made of the piezoelectric element 22a and the backing material 22c, the thickness dimension of the substrate 24, and the like, the back surface of the substrate 24 is located substantially close to the inner surface of the tip cap 21. In addition, since the length of the tip cap 21 in the axial direction is shortened, the ultrasonic transducer 22 is brought close to the tip of the cylindrical body 25. On the other hand, since the coaxial cable 26 is led out from the flexible shaft 23 and the cylindrical body 25 into the tip cap 21, the coaxial cable 26 is disposed at the axial center of the tip cap 21 or in the vicinity thereof. Therefore, in order to pull out the coaxial cable 26 to the back surface side of the substrate 24, it is necessary to bend approximately 90 ° at the position where the cylindrical body 25 is protruded, and from the coaxial cable 26 that wraps around the back surface side of the substrate 24. In order to connect the wirings 26a and 26b to the electrode patterns 31a and 31b, the coaxial cable 26 wrapping around the back surface side of the substrate 24 is further bent, but the bending at this portion needs to be 90 ° or more. There is. For this reason, the coaxial cable 26 bulges largely toward the inner surface side of the tip cap 21 on the back surface side of the substrate 24, and may be incorporated in a state where it may come into contact with the inner surface of the tip cap 21. The wall thickness of the tip cap 21 is thin, and therefore easily deforms when pressed from the outside.
[0012]
In the ultrasonic probe 10, the flexible shaft 23 is rotationally driven around the axis in the flexible sleeve 20 to scan the ultrasonic transducer 22 in the radial direction. When rotated, the bulging portion of the coaxial cable 26 that wraps around the back side of the substrate 24 may come into sliding contact with the inner surface of the tip cap 21. As a result, not only is the tip cap 21 damaged or deformed, but if it is severe, inconvenience such as disconnection occurs at the connection portions of the wirings 26a and 26b derived from the coaxial cable 26 to the electrode patterns 31a and 31b. Occurs.
[0013]
The present invention has been made in view of the above points, and an object of the present invention is to provide an ultrasonic transducer in which a coil is provided on the back side of a substrate on which an ultrasonic transducer is mounted. An object of the present invention is to allow the coaxial cable to be routed in a compact manner without causing the coaxial cable connected to the coil to substantially protrude from the back side of the substrate.
[0014]
[Means for Solving the Problems]
In order to achieve the above-described object, the present invention is provided with a tip cap attached to the tip of a flexible sleeve, and an ultrasonic transducer attached to a substrate is provided in the tip cap, and the tip of the flexible shaft is provided on the substrate. An ultrasonic probe that scans the ultrasonic transducer in the rotational direction by rotating the flexible shaft about the axis in connection with a portion of the substrate, the ultrasonic transducer mounting surface of the substrate, On the opposite side, a coil is attached and a pair of electrodes to which both ends of the coil are connected are provided, and the substrate has a notch at a position including a part of the mounting portion of the ultrasonic transducer. A coaxial cable inserted into the flexible shaft and extending along the lower surface of the ultrasonic transducer inside the notch of the substrate, In which wires derived from the coaxial cable is to its features that it has a structure to be connected to the respective electrodes.
[0015]
Terminals are provided at both ends of the coil, and these terminals are connected to electrodes provided on the back surface of the substrate. The electrode can be formed as an electrode pattern on the back surface of the substrate by printing or the like. Wiring drawn from the inner conductor and the outer conductor of the coaxial cable is connected to the electrodes. Only the wiring derived from the coaxial cable need only go around to the back side of the substrate, and the entire coaxial cable need not go around to the back side of the substrate. Therefore, a notch is formed in the substrate, and the tip end portion of the coaxial cable is accommodated in the notch. As a result, the coaxial cable does not protrude significantly on the back side of the substrate, and depending on the outer diameter of the coaxial cable, it is completely buried in the notch. In order to fix the coaxial cable arranged inside the notch, it is desirable to fill the inside of the notch with an adhesive. The flexible shaft can be directly connected to the substrate, but it is desirable from the viewpoint of assembling property to provide a member for connecting the flexible shaft and the substrate. This connecting member is made of a member having high strength such as metal, and is composed of a cylindrical body in which a large-diameter cylindrical portion located in the tip cap and a small-diameter cylindrical portion located in the flexible sleeve are connected. The tip of the flexible shaft can be connected to the small diameter cylindrical portion, and the substrate can be connected to the large diameter cylindrical portion.
[0016]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to FIGS. About the whole structure of an ultrasound diagnosing device, since there is no special difference from the thing of the prior art shown in FIG. 5, the same code | symbol is used about the same or equivalent member as FIG. Omitted. The ultrasonic diagnostic apparatus of FIG. 5 is assumed to be inserted into a body cavity using an endoscope as a guide means. However, the present invention is not limited to this type of ultrasonic diagnostic apparatus, either directly or otherwise. It may be guided by the guide means and inserted into the body cavity.
[0017]
Thus, FIG. 1 shows a cross section of the tip portion of the ultrasonic probe 50. The ultrasonic probe 50 has a distal end cap 52 connected to the distal end of a flexible sleeve 51, and an ultrasonic transducer 53 is mounted inside the distal end cap 52, and the ultrasonic transducer 53 is remotely connected by a flexible shaft 54. It is configured to be rotationally driven by operation and scan in the rotational direction. Further, since the large-sized ultrasonic transducer 53 is used, the distal end cap 52 of the flexible sleeve 51 inserted through the treatment instrument insertion channel 4 of the endoscope 1 is used as shown in FIG. It is larger than the diameter. About the above point, there is no exceptional difference with the ultrasonic probe 10 demonstrated by the prior art.
[0018]
The ultrasonic transducer 53 is mounted on the substrate 55, and the ultrasonic transducer 53 has the same configuration as that described in the prior art, that is, from the mounting side to the substrate 55, the backing material, the piezoelectric element, and the acoustic matching. In addition, an acoustic lens is laminated on the ultrasonic wave transmitting / receiving surface as necessary. The base end portion of the substrate 55 is connected to the cylindrical body 56, and the distal end portion of the flexible shaft 54 is directly connected to the cylindrical body 56. Inside the flexible sleeve 51, the cylindrical body 56 has a small-diameter portion 56a, a portion extending to the inside of the tip cap 52 is a large-diameter portion 56b, and the tip surface of the large-diameter portion 56b is the tip cap. An opening is formed inside 52, and a substrate 55 is connected to the opening.
[0019]
Here, in order to fix the connecting portion between the small-diameter cylindrical portion 56a of the cylindrical body 56 and the distal end of the flexible shaft 54, the distal end of the flexible shaft 54 is inserted into the small-diameter cylindrical portion 56a, and spot welding is performed from outside to a predetermined location. Like to do. On the other hand, the substrate 55 is connected to the large diameter cylindrical portion 56 b, and a flat mounting wall 57 is formed on the large diameter cylindrical portion 56 b, and the base end portion of the substrate 55 is joined to the mounting wall 57. Then, it is fixed in a connected state by a screw 58. Therefore, the entire cylindrical body 56 is made of a metal such as stainless steel so as to have high strength and to be welded and to facilitate workability.
[0020]
As shown in FIG. 2, a pair of electrode patterns 59a and 59b are formed on the back surface of the substrate 55, that is, the surface opposite to the surface on which the ultrasonic transducer 53 is mounted. Is formed. The terminals of the coil 60 are connected to these electrode patterns 59a and 59b by means such as soldering. In addition, through holes 61 a and 61 b are formed in the electrode patterns 59 a and 59 b in the substrate 55, and wirings 62 a and 62 b connected to electrodes formed on both the front and back surfaces of the piezoelectric element in the ultrasonic transducer 53. The electrode patterns 59a and 59b are connected to the electrode patterns 59a and 59b through the through holes 61a and 61b by means such as soldering.
[0021]
A coaxial cable 63 is inserted into the flexible shaft 54. The coaxial cable 63 passes through the cylindrical body 56 from the inside of the flexible shaft and extends into the distal end cap 52. Inside the distal end cap 52, the inner conductor and the outer portion of the coaxial cable 63 are connected. The wirings 63a and 63b are led out from the conductor. These wirings 63a and 63b are connected to electrode patterns 59a and 59b, respectively.
[0022]
Thus, the cylindrical body 56 is formed of a conductive metal, and so on, so that the state of the coaxial cable 63 is maintained until the position closest to the portion of the substrate 55 where the electrode patterns 59a and 59b are provided. Wirings 63a and 63b are led out in the vicinity of the positions where the electrode patterns 59a and 59b are provided. For this purpose, as shown in FIG. 2, the substrate 55 is provided with a transducer mounting portion 55a to which the ultrasonic transducer 53 is bonded over the entire surface, and extends from the transducer mounting portion 55a to the proximal end side. The connection part 55b joined to the attachment wall 57 of the body 56 is provided. The transducer mounting portion 55a has a slightly smaller width than the ultrasonic transducer 53, thereby widening the fixing area of the ultrasonic transducer 53 to the transducer mounting portion 55a, and the end of the substrate 55 during rotation. Is kept out of contact with the inner surface of the tip cap 52. The connecting portion 55b extending from the vibrator mounting portion 55a to the base end side has a width narrower than that of the vibrator mounting portion 55a, and a notch 64 is formed at an intermediate portion in the width direction. Accordingly, the connecting portion 55b is divided into two. As indicated by P in FIG. 1, the notch 64 extends from the base end portion of the connecting portion 55b to the inside of the transducer mounting portion 55a, and therefore the back surface of the ultrasonic transducer 53 is partially exposed. It has become.
[0023]
As shown in FIGS. 3 and 4, the coaxial cable 63 led out from the cylindrical body 56 extends obliquely downward from a transition portion from the small diameter cylindrical portion 56 a to the large diameter cylindrical portion 56 b in the cylindrical body 56, In the notch 64 formed in the board | substrate 55, it is extended so that the back surface side may be followed. Accordingly, the width dimension of the notch 64 is at least larger than the diameter of the coaxial cable 63, and the width dimension of the notch 64 is larger than the outer diameter of the coaxial cable 63 in consideration of the connection strength of the substrate 55 to the cylindrical body 56. The dimensions are slightly larger. As described above, the front end portion of the coaxial cable 63 is completely buried in the notch 64 and does not substantially float at least from the back surface side of the substrate 55. That is, the tip portion of the cable 63 is accommodated in a space formed between the notch 64 and the back surface of the ultrasonic transducer 53 and is in close contact with the back surface of the ultrasonic transducer 53.
[0024]
And wiring 63a, 63b is derived | led-out from the edge part of the coaxial cable 63 accommodated in the notch 64, these each wiring 63a, 63b rides on the back surface of the board | substrate 55, and a front-end | tip part is on electrode pattern 59a, 59b. Connected by soldering. Further, an adhesive 65 is filled in a space formed by the notch 64 serving as a receiving portion of the tip portion of the cable 63 and the back surface of the ultrasonic vibrator 53, and the coaxial cable 63 is filled with the adhesive 65. The leading end portion is fixed, and the lead-out portions of the wirings 63a and 63b are sealed.
[0025]
With the configuration described above, since the coil 60 is mounted on the back side of the substrate 55, the length in the axial direction of the tip cap 52, which is a hard portion, can be shortened. Here, when the ultrasonic probe 50 is incorporated into an endoscope, at least the distal end cap 52 protrudes from the distal end of the insertion portion, and is inserted into the body cavity in this state. Therefore, when the length of the distal end cap 52 is shortened, the operability for insertion into the body cavity is improved.
[0026]
The coaxial cable 63 inserted through the flexible shaft 54 is disposed at the approximate axial center position of the flexible sleeve 51, but is inside the cylindrical body 56, from the small-diameter cylindrical portion 56 a to the large-diameter cylindrical portion 56 b. It is bent from the transition part to the back surface direction of the substrate 55. However, since it wraps around the back surface of the ultrasonic transducer 53 in the notch 64 of the substrate 55, a drop D from the bending start end position to the terminal end position of the coaxial cable 63 is compared with the case where it wraps around the back surface side of the substrate. Since (FIG. 1) becomes smaller and the bending angle can be reduced, it can be drawn without difficulty.
[0027]
Moreover, the coaxial cable 63 is in close contact with the back surface of the ultrasonic transducer 53 inside the notch 64. Therefore, the coaxial cable 63 does not protrude greatly from the back surface of the substrate 55. Here, when the diameter of the coaxial cable 63 is set to be equal to or smaller than the thickness dimension of the substrate 55, the coaxial cable 63 is completely buried in the notch 64 of the substrate 55 and does not protrude at all from the back surface. As a result, the only member that protrudes on the back side of the substrate 55 is the coil 60. Therefore, even if the substrate 55 is rotated in order to perform ultrasonic scanning in the rotation direction by the ultrasonic probe 50, the substrate 55 is included. Thus, there is no possibility that a member provided in the tip cap 52 comes into contact with the inner surface of the tip cap 52. Therefore, the tip cap 52 is protected.
[0028]
Further, the front end portion of the coaxial cable 63 is disposed in a space surrounded by the side wall constituting the notch 64 of the substrate 55 and the back surface of the ultrasonic transducer 53 so that the adhesive 65 is filled inside. Thus, the coaxial cable 63 and the lead-out portions of the wirings 63a and 63b are firmly fixed. As a result, there is no possibility that the coaxial cable 63 escapes from this space, and there is no possibility that an unreasonable force acts on the wirings 63a, 63b and the like to cause disconnection. That is, the stability of the tip portion of the coaxial cable 63 is greatly improved.
[0029]
【The invention's effect】
As described above, in the ultrasonic probe in which the coil is provided on the back surface side of the substrate on which the ultrasonic transducer is mounted, the coaxial cable connected to the ultrasonic transducer and the coil is connected from the back surface side of the substrate. There is an effect that the coaxial cable can be routed in a compact manner without any substantial protrusion.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of a tip portion of an ultrasonic probe showing a first embodiment of the present invention.
FIG. 2 is a cross-sectional view taken along the line AA of FIG.
3 is a cross-sectional view taken along the line BB in FIG.
FIG. 4 is a perspective view of a substrate to which a coaxial cable is connected as viewed from the back side.
FIG. 5 is an overall configuration diagram of an ultrasonic diagnostic apparatus including an ultrasonic probe that is inserted into a body cavity using an endoscope as a guide means.
FIG. 6 is a cross-sectional view of a tip portion of an ultrasonic probe according to the prior art.
FIG. 7 is an equivalent circuit diagram when a coil is connected to an ultrasonic transducer.
8 is a bottom view of the substrate of FIG. 6. FIG.
[Explanation of symbols]
50 Ultrasonic probe 51 Flexible sleeve 52 Tip cap 53 Ultrasonic transducer 54 Flexible shaft 55 Substrate 55a Transducer mounting portion 55b Connection portion 56 Cylindrical body 56a Small diameter cylindrical portion 56b Large diameter cylindrical portions 59a, 59b Electrode pattern 60 Coil 63 Coaxial cable 63a, 63b Wiring 64 Notch 65 Adhesive

Claims (3)

A tip cap is attached to the tip of the flexible sleeve, and an ultrasonic transducer attached to the substrate is provided in the tip cap. The substrate is driven to rotate by a flexible shaft, and the ultrasonic transducer scans in the rotational direction. In the so-called ultrasonic probe,
A coil is attached to the side surface of the substrate opposite to the mounting surface of the ultrasonic transducer, and a pair of electrodes to which both ends of the coil are connected are provided.
The substrate has a notch formed at a position including a part of the mounting portion of the ultrasonic transducer,
A coaxial cable inserted through the flexible shaft extends along the lower surface of the ultrasonic transducer inside the notch of the substrate,
An ultrasonic probe characterized in that wiring derived from the coaxial cable is connected to the electrodes. 2. The ultrasonic probe according to claim 1, wherein the notch of the substrate is filled with an adhesive, and the coaxial cable is fixed by the adhesive. A metal cylinder having a large-diameter cylindrical portion located in the tip cap and a small-diameter cylindrical portion located in the flexible sleeve is provided, and the distal end of the flexible shaft is connected to the small-diameter cylindrical portion. The ultrasonic probe according to claim 1, wherein the substrate is connected to the large-diameter cylindrical portion.

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