Method for manufacturing a vibrator unit, and vibrator unit

Abstract

To provide a method for manufacturing a vibrator unit that is capable of reliably filling a filler into a housing of the vibrator unit.SOLUTION: A method for manufacturing a vibrator unit 10 includes a spacer / cable arrangement step and a filling step. In the spacer / cable arrangement step, a spacer 60 for partitioning an insertion hole 32 into two internal spaces 65, 66 extending along a longitudinal direction of a cable lead-out portion 31 is arranged in the cable lead-out portion 31, and a cable 50 is arranged in the insertion hole 32. In the filling step, one internal space 65 is caused to function as a filling path for a filler A1 while the other internal space 66 is caused to function as an air vent path when the filler A1 is filled in a state where the spacer 60 and cable 50 are arranged, and the filler A1 is filled into a main body portion 21 and the insertion hole 32.SELECTED DRAWING: Figure 6

Description

Technical Field

[0001] The present invention relates to a method for manufacturing a vibrator unit and a vibrator unit.

Background Art

[0002] Conventionally, there is known a vibrator unit that immerses a housing having a main body portion and a cylindrical cable lead-out portion in water and transmits and receives ultrasonic waves by an ultrasonic vibrator housed in the main body portion (see, for example, Patent Documents 1 and 2). A cable electrically connected to the ultrasonic vibrator is inserted into the insertion hole of the cable lead-out portion.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0004] By the way, when manufacturing the vibrator unit, a filler is poured from the upper part of the cable lead-out portion into the main body portion and hardened. However, when filling the filler, since the air in the main body portion is difficult to escape, there is a problem that the filling amount of the filler is not stable. As a result, if the filling amount is insufficient, there are problems such as a vibrator unit with low waterproof performance being produced or the variation in sensitivity characteristics becoming large. In addition, since the cable inserted into the insertion hole is likely to move within the insertion hole, the cable may interfere during the filling of the filler.

[0005] The present invention has been made in view of the above problems, and its objective is to provide a method for manufacturing a transducer unit that can reliably fill the housing of the transducer unit with a filler. Another objective is to provide a transducer unit that can suppress the movement of a cable placed in the insertion hole of the cable outlet. [Means for solving the problem]

[0006] To solve the above problems, the invention described in claim 1 is a method for manufacturing a transducer unit comprising: a housing having a main body and a cylindrical cable outlet portion protruding from the upper surface of the main body; an ultrasonic transducer housed in the main body of the housing; a cable electrically connected to the ultrasonic transducer and positioned in an insertion hole of the cable outlet portion; and a hardened filler material for filling gaps in the housing, the method comprising: a spacer-cable arrangement step of arranging a spacer in the cable outlet portion to divide the insertion hole into two internal spaces extending along the longitudinal direction of the cable outlet portion, and arranging the cable in the insertion hole; and a filling step of filling the main body portion and the insertion hole with the filler, with one of the internal spaces functioning as a filling path for the filler and the other internal space functioning as an air vent path during filling of the filler.

[0007] Accordingly, according to the invention described in claim 1, in the spacer-cable arrangement process, a spacer is placed in the cable exit section to divide the insertion hole into two internal spaces, so that one internal space is used as a filling path for the filler and the other internal space is used as an air venting path when filling the filler. Therefore, when the filler is filled into the main body from one internal space during the filling process, the air inside the main body can be reliably vented to the outside of the housing from the other internal space. As a result, the filler can be quickly filled into the main body, and the gaps inside the main body can be reliably filled with the filler. Thus, since the amount of filler filled is stable, the risk of manufacturing transducer units with low waterproofness due to insufficient filler can be reduced. In addition, variations in the sensitivity characteristics of each manufactured transducer unit can be reduced.

[0008] The invention described in claim 2 is characterized in that, in claim 1, the spacer is a tubular spacer having one of the internal spaces inside, and in the spacer-cable arrangement step, the cable is inserted through the other internal space.

[0009] The invention described in claim 3 is characterized in that, in claim 2, the tubular spacer is provided separately from the cable outlet and is housed within the cable outlet in a manner that extends substantially parallel to the cable.

[0010] The invention described in claim 4 is characterized in that, in claim 3, the tubular spacer has an upper end opening and a lower end opening, the upper end opening which also serves as an inlet for the filler is located near the outlet of the cable outlet, and the lower end opening is located inside the main body.

[0011] The invention described in claim 5 is characterized in that, in claim 4, the lower end of the tubular spacer is bent outward within the main body, and the lower end opening is located on the outer periphery of the main body.

[0012] The invention described in claim 6 is characterized in that, in claim 5, the gap between the inner surface of the main body and the upper end surface of the ultrasonic transducer is smaller than the inner diameter of the cable outlet.

[0013] The invention described in claim 7 is a transducer unit comprising a housing having a main body and a cylindrical cable outlet portion protruding from the upper surface of the main body, an ultrasonic transducer housed within the main body of the housing, a cable electrically connected to the ultrasonic transducer and positioned in a through-hole of the cable outlet portion, and a hardened filler material filling the gap inside the housing, wherein a spacer is positioned within the cable outlet portion to divide the through-hole into two internal spaces extending along the longitudinal direction of the cable outlet portion, the cable is positioned in one of the internal spaces, and the inside of the main body and the through-hole are filled with the hardened filler material.

[0014] Accordingly, according to the invention described in claim 7, by arranging a spacer within the cable exit section, the insertion hole is divided into two internal spaces. As a result, the cross-sectional area of ​​each internal space is reduced, and the cross-sectional area of ​​the internal space through which the cable is inserted is also reduced. Therefore, it is possible to suppress the movement of the cable inserted into the internal space. In other words, the cable can be held stably and linearly within the insertion hole with almost no movement, thereby reducing variations in quality.

[0015] The invention described in claim 8 is characterized in that, in claim 7, the spacer is a tubular spacer having one of the internal spaces inside, and the cable is inserted through the other internal space.

[0016] The invention described in claim 9 is characterized in that, in claim 8, the tubular spacer is provided separately from the cable outlet and is housed within the cable outlet in a manner that extends substantially parallel to the cable.

[0017] The invention according to claim 10 is, in claim 9, characterized in that the tubular spacer has upper and lower end openings, the upper end opening that also serves as the inlet for the filler is disposed near the outlet of the cable lead-out portion, and the lower end opening is disposed within the main body portion.

[0018] The invention according to claim 11 is, in claim 10, characterized in that the lower end portion of the tubular spacer is bent outward within the main body portion, and the lower end opening is disposed on the outer peripheral portion of the main body portion.

[0019] The invention according to claim 12 is, in claim 11, characterized in that the gap formed between the inner surface of the main body portion and the upper end surface of the ultrasonic vibrator is smaller than the inner diameter of the cable lead-out portion.

Advantages of the Invention

[0020] As described in detail above, according to the inventions described in claims 1 to 6, the filler can be reliably filled into the housing of the vibrator unit. Further, according to the inventions described in claims 7 to 12, the movement of the cable disposed within the insertion hole of the cable lead-out portion can be suppressed.

Brief Description of the Drawings

[0021] [Figure 1] Side view showing the vibrator unit in the present embodiment. [Figure 2] Cross-sectional view taken along line A-A of FIG. 1. [Figure 3] Exploded perspective view showing the internal structure of the vibrator unit. [Figure 4] Cross-sectional view taken along line B-B of FIG. 2. [Figure 5] Block diagram showing the electrical configuration of the vibrator unit. [Figure 6] Explanatory drawing showing the filling process. [Figure 7] Cross-sectional view showing the vibrator unit in another embodiment. [Figure 8] Cross-sectional view showing the vibrator unit in another embodiment. [Figure 9] Figure 8 shows a cross-sectional view of the CC line. [Figure 10] A cross-sectional view showing the insertion hole for the cable outlet in another embodiment. [Figure 11] A cross-sectional view showing the insertion hole for the cable outlet in another embodiment. [Figure 12] A cross-sectional view showing the insertion hole for the cable outlet in another embodiment. [Figure 13] A cross-sectional view showing the insertion hole for the cable outlet in another embodiment. [Figure 14] A cross-sectional view showing the insertion hole for the cable outlet in another embodiment. [Modes for carrying out the invention]

[0022] Hereinafter, one embodiment embodying the present invention will be described in detail with reference to the drawings.

[0023] As shown in Figures 1 and 2, the transducer unit 10 of this embodiment is a unit for a fish finder that detects schools of fish present in water by irradiating the water with ultrasonic waves. The transducer unit 10 comprises a housing 20, an ultrasonic transducer 40, and a cable 50.

[0024] The housing 20 has a main body 21 and a cylindrical cable outlet 31 protruding from the center of the upper surface 21a of the main body 21. The main body 21 has a case body 22 and a bottom plate 23. The case body 22 is a bottomed cylindrical case that opens at its lower end 22a, and is constructed with a concave cross-section by integrally forming the top portion 24 and side walls 25. The bottom plate 23 is a disc-shaped member. An annular packing 26 (see Figure 3) is provided on the outer circumference of the upper surface 23a of the bottom plate 23, which contacts the lower end 22a of the case body 22.

[0025] As shown in Figures 2 and 3, the side wall 25 of the case body 22 is provided with a groove 27 that opens on the inner circumferential surface 25a. The groove 27 extends along the entire circumferential direction of the case body 22. In addition, a plurality of (three in this embodiment) claw portions 28 are provided protruding from the outer circumference of the upper surface 23a of the bottom plate portion 23, at a position inside the packing 26. Each claw portion 28 is arranged at equal angular intervals (120° intervals in this embodiment) with respect to the center of the bottom plate portion 23. Each claw portion 28 is designed to engage with the groove 27 when the bottom plate portion 23 is attached to the case body 22.

[0026] Furthermore, the ultrasonic transducer 40 is housed within the main body portion 21 of the housing 20. The ultrasonic transducer 40 is composed of an acoustic matching layer 41 and a piezoelectric element 42. The piezoelectric element 42 is a disc-shaped ceramic plate formed using, for example, lead zirconate titanate (PZT), which is a piezoelectric ceramic. The piezoelectric element 42 has a front surface 43 and a back surface 44 opposite to the front surface 43. In addition, a front-side electrode (not shown) is formed on the front surface 43 of the piezoelectric element 42, and a back-side electrode (not shown) is formed on the back surface 44 of the piezoelectric element 42. In this embodiment, the entire front surface 43 of the piezoelectric element 42 is bonded to the acoustic matching layer 41 via the front-side electrode and an adhesive layer (not shown). The front surface 43 bonded to the acoustic matching layer 41 functions as an acoustic radiating surface for irradiating (transmitting) ultrasonic waves when the piezoelectric element 42 vibrates.

[0027] As shown in Figures 2 and 3, a sheet-like soundproofing material 46 (backing material) is attached to the back surface 44 of the piezoelectric element 42. The soundproofing material 46 is intended to absorb sound from the back surface 44 and suppress reverberation. Furthermore, a soundproofing material 47 (side material) is wrapped around the outer surface 45 of the piezoelectric element 42. The soundproofing material 47 is intended to absorb sound from the outer surface 45 and suppress reverberation. As for the soundproofing materials 46 and 47, resin materials or rubber containing particles or fibers made of metal or ceramics, or resin materials with dispersed pores (such as sponge) can be used.

[0028] As shown in Figures 2 and 4, a through hole 32 is provided inside the cable outlet section 31. The through hole 32 has a circular cross-section, with its upper end opening at the upper end of the cable outlet section 31 and its lower end opening inside the main body section 21. The upper end of the cable outlet section 31 is the cable outlet 50a (see Figure 2). A male screw structure 33 (see Figure 1) is formed on the outer circumferential surface of the cable outlet section 31. The male screw structure 33 is used to fix the housing 20 to a scupper hole (not shown) provided in the bottom of the ship (not shown).

[0029] The cable 50 is electrically connected to the ultrasonic transducer 40 and is inserted through the insertion hole 32 of the cable outlet 31. As shown in Figure 2, of the two wires 51 and 52 included in the cable 50, one wire 51 is connected to the front electrode and the other wire 52 is connected to the rear electrode. More specifically, wire 51 is connected by soldering or the like to a side terminal (not shown) extending outward from the front electrode. Wire 52 is connected by soldering or the like to the outer circumference of the rear electrode.

[0030] As shown in Figures 2 to 4, a cylindrical spacer 60 is installed inside the insertion hole 32 of the cable outlet section 31. The spacer 60, by being installed inside the insertion hole 32, plays a role in suppressing the movement of the cable 50, which is also located inside the insertion hole 32, when the filler A1 is filled. In this embodiment, the spacer 60 is in substantially contact with the outer surface of the cable 50. The spacer 60 in this embodiment is provided separately from the cable outlet section 31 and is housed inside the insertion hole 32 in a state where it extends substantially parallel to the cable 50. Furthermore, the spacer 60 in this embodiment is made of a resin material and has an upper end opening 61 and a lower end opening 62. In addition, the spacer 60 has a bellows section 63, which is a flexible portion, located near the lower end opening 62. The upper end opening 61 also serves as the inlet for the filler A1 and is located near the outlet 50a of the cable outlet section 31. On the other hand, the lower end opening 62 also serves as an outlet for the filler A1 and is located within the main body 21. Specifically, the lower end portion 60a of the spacer 60 (the portion closer to the lower end opening 62 than the bellows portion 63) bends approximately at a right angle to the outer circumference within the main body 21, starting from the bellows portion 63. Therefore, the lower end opening 62 is located on the outer circumference of the main body 21, and is positioned further outward than the outer surface 45 of the piezoelectric element 42. The lower end portion 60a of the spacer 60 is attached to the upper end surface 40a of the ultrasonic transducer 40, specifically to the upper end surface 46a of the soundproofing material 46, via double-sided tape 64 (see Figures 2 and 3). Note that the lower end portion 60a of the spacer 60 is located on a side different from the side where the cable 50 is located.

[0031] Furthermore, the spacer 60 also serves to divide the insertion hole 32 into two internal spaces 65 and 66 that extend along the longitudinal direction of the cable outlet 31 over almost its entire length. More specifically, the spacer 60 has one internal space, the first internal space 65, inside. The first internal space 65 has a circular cross-section and serves as a filling path for the filler A1. The other internal space, the second internal space 66, through which the cable 50 is inserted, leaving a gap around it. The second internal space 66 is the space obtained by subtracting the first internal space 65 from the internal space of the insertion hole 32, and functions as an air venting path when filling with the filler A1. The cross-sectional area of ​​the cable 50 is approximately equal to the cross-sectional area of ​​the first internal space 65. The cross-sectional area of ​​the second internal space 66 is larger than the cross-sectional area of ​​the first internal space 65.

[0032] As shown in Figure 2, the gap S1 between the ceiling surface 21b (inner surface) of the main body 21 and the upper end surface 40a of the ultrasonic transducer 40 (i.e., the back surface 44 of the piezoelectric element 42) is smaller than the inner diameter D1 of the cable outlet section 31. Furthermore, the gap S2 between the ceiling surface 21b and the upper end surface 46a of the soundproofing material 46 attached to the upper end surface 40a is also smaller than the inner diameter D1 of the cable outlet section 31.

[0033] Furthermore, in this embodiment, the gaps within the housing 20, specifically the entire interior of the main body 21 and the entire interior of the insertion hole 32 (i.e., the first internal space 65 and the second internal space 66), are filled with the hardened filler A1. More specifically, the filler A1 adheres to the entire inner surface of the main body 21, specifically the entire ceiling surface 21b of the main body 21, the entire inner circumferential surface 25a of the side wall 25, the inner surface of the groove 27 that opens at the inner circumferential surface 25a, and the outer periphery of the upper surface 23a of the bottom plate 23. In addition, the filler A1 adheres to the entire outer surface of the ultrasonic transducer 40, specifically the outer circumferential surface of the acoustic matching layer 41, the outer circumferential portion of the upper surface of the acoustic matching layer 41, a part of the outer circumferential surface 45 of the piezoelectric element 42, the outer circumferential surface of the soundproofing material 46, the entire upper surface of the double-sided tape 64 attached to the entire upper end surface 46a of the soundproofing material 46, and the entire outer surface of the soundproofing material 47. Furthermore, the filler A1 adheres tightly to the entire inner surface of the insertion hole 32. The filler A1 also adheres tightly to the entire inner and outer surfaces of the cylindrical spacer 60, and to the entire outer surface of the cable 50. In this embodiment, the filler A1 is made of a resin material (epoxy resin, urethane resin, silicone resin, etc.) or an adhesive (two-component curing type epoxy adhesive, rubber adhesive, etc.).

[0034] Next, the electrical configuration of the oscillator unit 10 will be described.

[0035] As shown in Figure 5, the liquid crystal monitor (not shown) of the oscillator unit 10 is equipped with a control device 70 that comprehensively controls the entire device. The control device 70 is composed of a well-known computer consisting of a CPU 71, ROM 72, RAM 73, etc.

[0036] The CPU 71 is electrically connected to the ultrasonic transducer 40 via the transmitting / receiving circuit 74. The transmitting / receiving circuit 74 outputs an oscillation signal to the ultrasonic transducer 40 to drive it. As a result, the ultrasonic transducer 40 irradiates (transmits) ultrasonic waves into the water. The transmitting / receiving circuit 74 also receives an electrical signal indicating the ultrasonic waves (reflected waves) received by the ultrasonic transducer 40. Furthermore, the CPU 71 is electrically connected to the operation unit 75 and the display unit 76 of the liquid crystal monitor, respectively.

[0037] The CPU 71, shown in Figure 5, controls the transmitting / receiving circuit 74 to emit ultrasonic waves from the ultrasonic transducer 40. The CPU 71 also receives a received signal via the transmitting / receiving circuit 74, which is generated when the ultrasonic transducer 40 receives a reflected wave. Based on the received signal, the CPU 71 generates detection image data and stores the generated detection image data in the RAM 73. Based on the detection image data stored in the RAM 73, the CPU 71 controls the display unit 76 to display the detection image.

[0038] Next, we will explain how to explore underwater using the transducer unit 10.

[0039] First, the power to the transducer unit 10 and the liquid crystal monitor (not shown) is turned on. The liquid crystal monitor is used, for example, while being held by an operator. Next, the CPU 71 of the control device 70 controls the ultrasonic transducer 40 to output an oscillation signal from the transmitting / receiving circuit 74 via the cable 50, thereby driving the ultrasonic transducer 40. At this time, the piezoelectric element 42 repeatedly expands and contracts in the thickness direction. As a result, the piezoelectric element 42 vibrates, and ultrasonic waves are emitted (transmitted) from the ultrasonic transducer 40 into the water. When the ultrasonic waves reach the school of fish or the lake bottom, they are reflected by the school of fish or the lake bottom, becoming reflected waves that propagate towards the transducer unit 10 and are input (received) by the ultrasonic transducer 40. Subsequently, the ultrasonic waves (reflected waves) received by the ultrasonic transducer 40 are converted into a received signal and input to the CPU 71 via the cable 50 and the transmitting / receiving circuit 74. The CPU 71 visualizes the amplitude and time (timing) information of the received signal obtained through this series of transmissions and displays it on the display unit 76.

[0040] Next, the manufacturing method of the vibrator unit 10 will be described.

[0041] First, an acoustic matching layer 41 is prepared. A ceramic plate-like material to be used as a piezoelectric element 42 is also prepared. Specifically, a disc-shaped ceramic sintered body made of lead zirconate titanate (PZT) is fabricated, and then the surface is polished to obtain a ceramic plate-like material. Next, a front electrode is formed on the front surface 43 of the ceramic plate-like material, and a back electrode is formed on the back surface 44 of the ceramic plate-like material. Specifically, silver paste is applied to the front surface 43 and back surface 44 of the ceramic plate-like material, respectively, and the applied silver paste is fired to form the front electrode and back electrode. Then, a polarization treatment is performed to polarize the ceramic plate-like material in the thickness direction by applying a voltage between the front electrode and the back electrode.

[0042] Next, a ceramic plate is bonded to one side of the acoustic matching layer 41 via the front electrode. Specifically, an adhesive (such as an epoxy adhesive) is applied to either the surface of the front electrode or the surface of the acoustic matching layer 41 to bond and fix the ceramic plate to the acoustic matching layer 41. At this point, the ultrasonic transducer 40 is completed. Alternatively, brazing using solder or the like may be performed instead of applying adhesive.

[0043] Furthermore, after the ultrasonic transducer 40 is completed, wiring 51 is connected to the front electrode via side terminals (not shown) by soldering, and wiring 52 is connected to the rear electrode by soldering. Next, soundproofing material 47 to suppress reverberation is wrapped around the outer surface 45 of the piezoelectric element 42, and then soundproofing material 46 to suppress reverberation is attached to the back surface 44 of the piezoelectric element 42. After that, the ultrasonic transducer 40 is housed in the main body 21 of the housing 20. Then, with the ultrasonic transducer 40 in place, it is bonded to the main body 21.

[0044] Next, the spacer and cable placement process is performed, and the cable 50, including the wirings 51 and 52, is inserted into the insertion hole 32 of the cable outlet section 31. Furthermore, a spacer 60 is installed (placed) inside the insertion hole 32. As a result, the insertion hole 32 is divided into two internal spaces 65 and 66, and the spacer 60 is in near-contact with the outer surface of the cable 50, so that the cable 50 is held stably and linearly within the insertion hole 32 with almost no movement.

[0045] In the subsequent filling process, with the spacer 60 installed and the cable 50 inserted, the first internal space 65 is made to function as a filling path for the filler A1, and the second internal space 66 is made to function as an air venting path during the filling of the filler A1 (see Figure 6). Then, the filler A1 is filled into the main body 21 and the insertion hole 32. Specifically, first, the filler A1 is filled into the main body 21 from the filling path in the spacer 60 (first internal space 65), filling the gaps inside the housing 20. As the filler A1 is filled, the air A2 inside the main body 21 (see Figure 6) is discharged outside the transducer unit 10 by passing through the air venting path in the cable outlet 31 (second internal space 66). Furthermore, the filler A1 extends to the upper surface 23a of the bottom plate portion 23 and also to the upper end opening (outlet 50a) of the cable outlet portion 31 (insertion hole 32), thereby ensuring that the housing 20 is sealed.

[0046] Then, the housing 20 is left to stand and the filler A1 is allowed to harden. Depending on the type of filler A1, heat treatment is also performed to harden the filler A1. At this point, the transducer unit 10 is completed with the spacer 60 remaining inside the cable outlet 31.

[0047] Next, the main body 21 of the transducer unit 10 is inserted from the outside of the ship into the scupper hole (not shown) of the scupper (not shown). The upper surface 21a of the main body 21 is then brought into contact with the bottom of the ship (not shown). At this point, the cable outlet 31 is inserted through the scupper hole. Then, an annular packing (not shown) surrounding the cable outlet 31 is placed on the scupper, and the female threaded part of the nut (not shown) is screwed onto the male threaded part 33 of the cable outlet 31 and tightened. As a result, the upper surface 21a of the main body 21 is in close contact with the outer surface of the bottom of the ship, and the scupper and nut are watertight due to the packing, fixing the main body 21 to the scupper and completing the assembly of the transducer unit 10.

[0048] Therefore, according to this embodiment, the following effects can be obtained.

[0049] (1) During the manufacturing of the transducer unit 10 of this embodiment, the filler A1 is poured into the main body 21 through the insertion hole 32 of the cable outlet 31. However, if the inside of the insertion hole 32 is blocked with the filler A1 before the inside of the main body 21 is filled with the filler A1, it becomes difficult for the air A2 inside the main body 21 to escape, which causes a problem in that it takes a long time to fill with the filler A1. In addition, there is a problem in that the hardening of the filler A1 is completed while a cavity remains inside the main body 21.

[0050] Therefore, in this embodiment, by installing a spacer 60 inside the cable outlet 31 during the spacer cable placement process, the inside of the spacer 60 is used as a filling path for the filler A1 (first internal space 65), and the outside of the spacer 60 is used as an air venting path (second internal space 66) when filling the filler A1. As a result, when the filler A1 is filled into the main body 21 from the first internal space 65 during the filling process, the air A2 inside the main body 21 can be reliably vented to the outside of the housing 20 from the second internal space 66. Furthermore, since the cable 50 is inserted through the second internal space 66, which does not function as a filling path for the filler A1, the filler A1 can be filled without being obstructed by the cable 50. As a result, the filler A1 can be quickly filled into the main body 21, and the gaps inside the main body 21 can be reliably filled with the filler A1. Therefore, since the amount of filler A1 filled is stable, the risk of manufacturing a transducer unit 10 with low waterproofness due to insufficient fill is reduced. Furthermore, it is possible to reduce variations in the sensitivity characteristics of each manufactured transducer unit 10.

[0051] (2) In this embodiment, the gap S2 between the ceiling surface 21b of the main body 21 and the upper end surface 46a of the soundproofing material 46 is smaller than the inner diameter D1 of the cable outlet 31. Also, since the ultrasonic transducer 40 in this embodiment is a transducer for low frequencies, the piezoelectric element 42 is thicker and the position of the upper end surface 46a tends to be higher. As a result of the above, the gap S2 tends to become narrower, and the filler A1 tends to get stuck in the gap S2. Therefore, the lower end opening 62 of the spacer 60 is placed on the outer circumference of the main body 21 and the lower end opening 62 is spaced apart from the gap S2 and the insertion hole 32 of the cable outlet 31, so that the filler A1 discharged from the lower end opening 62 does not enter the gap S2 or the insertion hole 32. Therefore, the gap S2 and insertion hole 32 are less likely to be blocked by the filler A1, preventing the air A2 inside the main body 21 from being released from the second internal space 66 to the outside of the housing 20, and reliably eliminating the problem of the filler A1 overflowing from the outlet 50a of the cable outlet 31. In addition, because the gap S2 is narrow, the main body 21 can be made low and compact.

[0052] (3) In this embodiment, by installing a spacer 60 inside the cable exit section 31, the insertion hole 32 is divided into two internal spaces 65 and 66. As a result, the cross-sectional area of ​​each internal space is reduced, and the cross-sectional area of ​​the second internal space 66 through which the cable 50 is inserted is also reduced. Therefore, it is possible to suppress the movement of the cable 50 inserted into the second internal space 66. In other words, the cable 50 can be held stably and linearly within the insertion hole 32 with almost no movement, and variations in quality can be reduced.

[0053] (4) In this embodiment, the lower end portion 60a of the spacer 60 is positioned on a side different from the side where the cable 50 is located. This prevents interference between the lower end portion 60a and the wiring 51, 52 included in the cable 50, so that the wiring 51, 52 does not obstruct the flow of the filler A1 during filling, and the filler A1 can be filled smoothly and reliably.

[0054] The above embodiment may be modified as follows.

[0055] In the above embodiment, the lower end portion 60a of the spacer 60 is bent outward within the main body portion 21, and the lower end opening 62 is located on the outer periphery of the main body portion 21. However, as shown in Figure 7, a tubular spacer 80 extending linearly from the upper end opening 81 to the lower end opening 82 may be installed within the cable outlet portion 31, and the lower end opening 82 may be located in the central part of the main body portion 21. Furthermore, the lower end opening 82 may be cut diagonally so that it opens diagonally downward toward the outer periphery of the cable outlet portion 31. With this configuration, it becomes easier to guide the filler A1 toward the outer periphery of the main body portion 21 compared to when the lower end opening 82 is simply cut horizontally.

[0056] In the above embodiment, the tubular spacer 60 was bent at a right angle in the bellows section 63, but this is not limited to that. For example, instead of having a bellows section 63, the spacer may have a bent portion located closer to the lower end opening 82. Also, in the above embodiment, the tubular spacer 60 was made of a resin material, but it may be made of a material other than a resin material (for example, metal).

[0057] In the above embodiment, a tubular spacer 60 was installed in the insertion hole 32 of the cable outlet section 31. However, as shown in Figures 8 and 9, a plate-shaped spacer 90 may be installed in the insertion hole 32. The spacer 90 is housed in the cable outlet section 31 in a manner that extends substantially parallel to the cable 50. A guide wall 91 may be provided at the lower end of the spacer 90, which curves outward within the main body section 21 to guide the filler A1 to the outer periphery within the main body section 21. The spacer 90 may be provided separately from the cable outlet section 31, or it may be integrally formed with the cable outlet section 31.

[0058] Furthermore, as shown in Figure 10, a plate-shaped spacer 100 may be installed in the insertion hole 32 so as to sandwich the cable 50 between it and the inner surface of the insertion hole 32. In this way, the movement of the cable 50 can be reliably suppressed. Alternatively, as shown in Figure 11, a plate-shaped spacer 110 that curves along the outer surface of the cable 50 may be installed in the insertion hole 32. This also makes it easier to suppress the movement of the cable 50.

[0059] In the above embodiment, a cylindrical spacer 60 was installed in the insertion hole 32 of the cable outlet 31, but a spacer of another shape may be installed. For example, a square cylindrical spacer 120 (see Figure 12) or a semicircular cylindrical spacer 130 (see Figure 13) may be installed in the insertion hole 32. Alternatively, an elliptical, rectangular, hexagonal, or other cylindrical spacer may be installed in the insertion hole 32.

[0060] In the above embodiment, the lower end portion 60a of the spacer 60 was joined to the upper end surface 46a of the soundproofing material 46 via double-sided tape 64, but it may be joined to the upper end surface 46a of the soundproofing material 46 via other joining members. For example, the lower end portion 60a of the spacer 60 may be bonded to the upper end surface 46a with adhesive, or it may be attached to the upper end surface 46a using mounting brackets or the like.

[0061] In the above embodiment, a spacer 60 was installed in the insertion hole 32 of the cable outlet section 31, but a commercially available flexible straw or the like may be used as the spacer 60.

[0062] In the above embodiment, the tubular spacer 60 was provided separately from the cable outlet 31. However, as shown in Figure 14, the tubular spacer 140 may be integrally formed with the cable outlet 31.

[0063] In the spacer-cable placement process of the above embodiment, the cable 50 was inserted into the insertion hole 32 of the cable exit section 31, and then the spacer 60 was installed. However, after installing the spacer 60 in the insertion hole 32, the cable 50 may be inserted into the second internal space 66 of the insertion hole 32, leaving a gap around it.

[0064] In the above embodiment, the cable 50 was inserted through the second internal space 66 of the two internal spaces 65 and 66 partitioned in the insertion hole 32 of the cable outlet 31. However, the cable 50 may also be inserted through the first internal space 65. However, the first internal space 65 in the above embodiment is a space within the spacer 60, and its cross-sectional area is approximately equal to the cross-sectional area of ​​the cable 50, so the cable 50 cannot be inserted through it. Therefore, it is preferable that the first internal space has a cross-sectional area larger than the cross-sectional area of ​​the cable 50 and a minimum inner diameter larger than the outer diameter of the cable 50.

[0065] • In the above embodiment, the housing 20 had a cylindrical cable outlet portion 31, but it may have a cable outlet portion of another shape. For example, it may have an elliptical cable outlet portion, or a polygonal cable outlet portion such as a rectangular or hexagonal cable outlet portion.

[0066] The ultrasonic transducer 40 in the above embodiment was equipped with a disc-shaped piezoelectric element 42. However, the ultrasonic transducer 40 may be equipped with piezoelectric elements divided into multiple vibrating parts by forming multiple notches. For example, the ultrasonic transducer 40 may be equipped with a 1-3 composite structure piezoelectric element divided into multiple columnar vibrating parts by forming notches extending vertically and horizontally. Alternatively, the ultrasonic transducer 40 may be equipped with a 2-2 composite structure piezoelectric element divided into multiple strip-shaped vibrating parts by forming notches extending in one direction.

[0067] In this configuration, each vibrating section becomes more easily deformable in the thickness direction of the piezoelectric element, making the piezoelectric element more easily deformable in each part. As a result, the piezoelectric element vibrates more easily, increasing the electromechanical coupling coefficient and widening the frequency bandwidth. Furthermore, when forming a strip-shaped vibrating section by creating a cut extending in one direction, the number of cuts required to form the vibrating section is halved compared to forming a columnar vibrating section by creating cuts extending vertically and horizontally, making cut formation easier. Therefore, the manufacturing cost of the ultrasonic transducer 40 can be reduced. In addition, the strip-shaped vibrating section is longer in the planar direction than the columnar vibrating section. In this case, the strength of the vibrating section is increased, improving the reliability of the ultrasonic transducer 40.

[0068] Furthermore, the ultrasonic transducer 40 may include annular or rectangular piezoelectric elements. Alternatively, piezoelectric elements with an O-3 composite structure, which are made by mixing piezoelectric ceramic particles with a rubber material, or piezoelectric elements made of porous piezoelectric ceramics (porous elements) may be used.

[0069] In the above embodiment, an acoustic matching layer 41 was sandwiched between the piezoelectric element 42 and the bottom plate portion 23, but since the bottom plate portion 23 also serves as an acoustic matching layer, the acoustic matching layer 41 may be omitted. Furthermore, the acoustic matching layer 41 is not limited to being made of a single type of material, but may be a multilayer matching layer made by laminating multiple types of materials.

[0070] In the above embodiment, a groove 27 opening on the inner circumferential surface 25a is provided on the side wall 25 of the case body 22, and three claws 28 that engage with the groove 27 are provided protruding from the upper surface 23a of the bottom plate 23. However, there may be one or two claws 28, or four or more claws 28. Note that the claws 28 and groove 27 may not be provided at all.

[0071] • In the above embodiment, an example of using the transducer unit 10 in a fish finder was shown, but it is not limited to this and may be used in other measuring instruments. For example, the transducer unit 10 may be used in sonar that electrically or mechanically changes the direction of ultrasonic irradiation, or in measuring instruments such as depth sounders that measure water depth or airborne sensors that measure distance in the air.

[0072] Next, in addition to the technical ideas described in the claims, the technical ideas that can be grasped by the embodiments described above are listed below.

[0073] (1) The vibrator unit according to claim 11, characterized in that the tubular spacer has a bellows section at a position near the lower end opening.

[0074] (2) The transducer unit according to claim 11, characterized in that the lower end of the tubular spacer is joined to the upper end surface side of the ultrasonic transducer via a joining member.

[0075] (3) The transducer unit according to claim 11, characterized in that the lower end opening of the tubular spacer is opened in a manner that avoids the location of wiring extending from the cable within the main body.

[0076] (4) The vibrator unit according to claim 8, characterized in that the tubular spacer is integrally formed with the cable outlet portion.

[0077] (5) The transducer unit according to any one of claims 7 to 12, characterized in that the transducer unit is a transducer unit for a fish finder. [Explanation of Symbols]

[0078] 10…Oscillator unit 20…Cabinet 21...Main body 21a... Top surface of the main body 21b...Ceiling surface as the inner surface of the main body 31…Cable outlet 32…Through hole 40… Ultrasonic transducer 40a...Upper end surface of the ultrasonic transducer 50… Cable 50a...Drawer opening 60, 80, 120, 130, 140… Tubular spacers 60a...Lower end of spacer 61,81...Top end opening 62,82…Bottom end opening 65...The first internal space as one of the internal spaces 66... ​​The second internal space as the other internal space 90, 100, 110… Spacers A1... Filler D1...Inner diameter of the cable outlet S1... The gap between the inner surface of the main body and the upper end surface of the ultrasonic transducer.

Claims

1. A method for manufacturing a transducer unit comprising: a housing having a main body and a cylindrical cable outlet protruding from the upper surface of the main body; an ultrasonic transducer housed within the main body of the housing; a cable electrically connected to the ultrasonic transducer and positioned in the insertion hole of the cable outlet; and a hardened filler material for filling gaps within the housing, A spacer-cable placement step is to place a spacer within the cable outlet section that divides the insertion hole into two internal spaces extending along the longitudinal direction of the cable outlet section, and to place the cable within the insertion hole. With the spacer and cable in place, the filling process involves filling the main body and the insertion hole with the filler by making one of the internal spaces function as a filling path for the filler and the other internal space function as an air vent path during filling of the filler. A method for manufacturing a vibrator unit, characterized by including the following:

2. The spacer is a tubular spacer having the internal space on one side, In the spacer cable placement process, the cable is inserted into the other internal space. A method for manufacturing the vibrator unit according to claim 1.

3. The method for manufacturing a transducer unit according to claim 2, characterized in that the tubular spacer is provided separately from the cable outlet and is housed within the cable outlet in a manner that extends substantially parallel to the cable.

4. The method for manufacturing a transducer unit according to claim 3, characterized in that the tubular spacer has an upper end opening and a lower end opening, the upper end opening which also serves as an inlet for the filler is located near the outlet of the cable outlet, and the lower end opening is located inside the main body.

5. The method for manufacturing a vibrator unit according to claim 4, characterized in that the lower end of the tubular spacer is bent outward within the main body, and the lower end opening is located on the outer circumference of the main body.

6. The method for manufacturing a transducer unit according to claim 5, characterized in that the gap between the inner surface of the main body and the upper end surface of the ultrasonic transducer is smaller than the inner diameter of the cable outlet.

7. A transducer unit comprising a housing having a main body and a cylindrical cable outlet protruding from the upper surface of the main body, an ultrasonic transducer housed within the main body of the housing, a cable electrically connected to the ultrasonic transducer and positioned in the insertion hole of the cable outlet, and a hardened filler material that fills the gaps inside the housing, A spacer is placed inside the cable outlet that divides the insertion hole into two internal spaces extending along the longitudinal direction of the cable outlet. The cable is placed in either of the aforementioned internal spaces. The inside of the main body and the insertion hole are filled with the hardened material of the filler. A vibrator unit characterized by the following features.

8. The vibrator unit according to claim 7, characterized in that the spacer is a tubular spacer having one of the internal spaces inside, and the cable is inserted through the other internal space.

9. The vibrator unit according to claim 8, characterized in that the tubular spacer is provided separately from the cable outlet and is housed within the cable outlet in a manner that extends substantially parallel to the cable.

10. The vibrator unit according to claim 9, characterized in that the tubular spacer has an upper end opening and a lower end opening, the upper end opening which also serves as an inlet for the filler is located near the outlet of the cable outlet, and the lower end opening is located inside the main body.

11. The transducer unit according to claim 10, characterized in that the lower end of the tubular spacer is bent outward within the main body, and the lower end opening is located on the outer circumference of the main body.

12. The transducer unit according to claim 11, characterized in that the gap between the inner surface of the main body and the upper end surface of the ultrasonic transducer is smaller than the inner diameter of the cable outlet.

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