Method of fabricating ultrasonic coupler

• US 5,882,557 A
• Filed: 07/05/1996
• Issued: 03/16/1999
• Est. Priority Date: 12/15/1992
• Status: Expired due to Fees

• Current Assignee: Fukuda Denshi Company Limited
• Original Assignee: Fujitsu Limited
• Inventors: Takeda, Shiro, Watanabe, Kazuhiro, Matsui, Kiyoto, Hayakawa, Kenichi
• Primary Examiner(s): AFTERGUT, KAREN K
• Application Number:
  US08/675,841
• Time in Patent Office: 984 Days
• Field of Search: 264/28, 264/313, 264/279, 264/219, 264/273, 264/274, 264/278, 264/337
• US Class Current: 264/28
• CPC Class Codes: B29C 39/006 Monomers or prepolymers by reaction injection moulding B29C67/246
• CPC Class Codes: B29C 39/18 incorporating preformed parts or layers, e.g. casting around inserts or for coating articles B29C39/206 takes precedence
• CPC Class Codes: B29C 39/38 Heating or cooling
• CPC Class Codes: B29C 39/40 Compensating volume change, e.g. retraction in general B29C37/005
• CPC Class Codes: B29C 70/72 Encapsulating inserts having non-encapsulated projections, e.g. extremities or terminal portions of electrical components B29C70/742 takes precedence
• CPC Class Codes: B29K 2029/04 PVOH, i.e. polyvinyl alcohol B29K2031/04 takes precedence
• CPC Class Codes: G10K 11/02 Mechanical acoustic impedances; Impedance matching, e.g. by horns; Acoustic resonators

Abstract

A method of fabricating an ultrasonic coupler to a specified configuration such that the ultrasonic coupler is fabricated by freezing and defrosting an aqueous solution containing a polymer. A surface of the fabricated ultrasonic coupler is made to be smooth. The ultrasonic coupler is fabricated using an ultrasonic coupler fabricating die including members each made of silicone rubber which varies in compliance with the expansion and the contraction of the aqueous solution. To fabricate the ultrasonic coupler, the aqueous solution containing a polyvinyl alcohol (PVA) is poured into the die. Then, the die is subjected to the process of cooling to below the freezing point and the process of recovery to room temperature so as to progress a bridging of the PVA, thereby progressing a gelling of the aqueous solution.

Claims

1. A method of fabricating an ultrasonic coupler, comprising the steps of:

preparing a die, wherein at least part of the die is provided with an elastic body with expanding and contracting properties, said step of preparing a die including

forming a first die for forming a junction plane of the ultrasonic coupler and an ultrasonic probe to be contacted by the ultrasonic coupler as a part of a configuration of the ultrasonic coupler, the first die being adapted to detachably mount a connection member for connecting the ultrasonic coupler with the ultrasonic probe, and thereby allowing a simultaneous connection of the ultrasonic coupler to the connection member during formation of the ultrasonic coupler, and

forming a second die, used in conjunction with the first die, for forming the configuration of the ultrasonic coupler except for the junction plane;

pouring an aqueous solution containing a polymer into the prepared die; and

freezing and defrosting the poured aqueous solution to form the ultrasonic coupler having the connection member connected thereto.

2. The method of fabricating an ultrasonic coupler according to claim 1, further comprising;

facing the first die downwards, such that the first die is a top die, and

forming an inlet in the first die for pouring the aqueous solution into the die; and

said step of forming a second die further comprising;

forming a bottom wall comprising an elastic body having a thickness of no greater than 2 mm for the second die, the second die being a bottom die.

3. The method of fabricating an ultrasonic coupler according to claim 1, wherein the elastic body is a silicone rubber.

4. The method of fabricating an ultrasonic coupler according to claim 1, wherein the polymer is a polyvinyl alcohol.

5. The method of fabricating an ultrasonic coupler according to claim 1, wherein a coefficient of extension of the elastic body is at least 40%.

6. The method of fabricating an ultrasonic coupler according to claim 1, wherein said step of fabricating a second die comprises forming a bottom wall of the second die having a degree of flexibility greater than all other portions of the first and second dies.

7. The method of fabricating an ultrasonic coupler according to claim 1, wherein said step of fabricating a second die comprises forming a bottom wall of the second die having a thickness less than all other portions of the first and second dies.

8. The method of fabricating an ultrasonic coupler according to claim 1, wherein:

said step of fabricating a first die includes forming a convex surface in the first die between positions of attachment with the connecting member;

said step of fabricating a second die includes forming a pouring inlet in the second die; and

said method of fabricating an ultrasonic coupler further comprising the steps of

attaching the connecting member to the first die at the corresponding positions of attachment,

placing the second die over the first die, and

pouring of the aqueous solution into the die;

wherein during the freezing and defrosting of the poured aqueous solution, the connecting member connects to the ultrasonic coupler formed from the aqueous solution.

9. The method of fabricating an ultrasonic coupler according to claim 1, wherein:

said step of fabricating a first die includes forming the first die in a T-shape and forming a pouring inlet in the first die; and

said method of fabricating an ultrasonic coupler further comprising the steps of

attaching the connecting member to the first die,

placing the first die over the second die, and

ceasing the pouring of the aqueous solution into the die when the aqueous solution reaches the lowest extending portion of the first die after the first die is placed over the second die;

wherein during the freezing and defrosting of the poured aqueous solution, the connecting member connects to the ultrasonic coupler formed from the aqueous solution.

10. A method of fabricating an ultrasonic coupler, comprising the steps of:

preparing a die, wherein at least part of the die is provided with a flexible body with expanding and contracting properties, said step of preparing a die including

forming a first die for forming a junction plane of the ultrasonic coupler and an ultrasonic probe to be contacted by the ultrasonic coupler as a part of a configuration of the ultrasonic coupler, the first die being adapted to detachably mount a connection member for connecting the ultrasonic coupler with the ultrasonic probe, and thereby allowing a simultaneous connection of the ultrasonic coupler to the connection member during formation of the ultrasonic coupler, and

forming a second die, used in conjunction with the first die, for forming the configuration of the ultrasonic coupler except for the junction plane;

pouring an aqueous solution containing a polymer into the prepared die; and

freezing and defrosting the poured aqueous solution to form the ultrasonic coupler having the connection member connected thereto.

11. The method of fabricating an ultrasonic coupler according to claim 10, further comprising:

facing the first die downwards, such that the first die is a top die, and

forming an inlet in the first die for pouring the aqueous solution into the die; and

said step of forming a second die further comprising;

forming a bottom wall comprising a flexible body having a thickness of no greater than 2 mm for the second die, the second die being a bottom die.

12. The method of fabricating an ultrasonic coupler according to claim 10, wherein said step of fabricating a second die comprises forming a bottom wall of the second die having a degree of flexibility greater than all other portions of the first and second dies.

13. The method of fabricating an ultrasonic coupler according to claim 10, wherein said step of fabricating a second die comprises forming a bottom wall of the second die having a thickness less than all other portions of the first and second dies.

14. The method of fabricating an ultrasonic coupler according to claim 10, wherein:

said step of fabricating a first die includes forming a convex surface in the first die between positions of attachment with the connecting member;

said step of fabricating a second die includes forming a pouring inlet in the second die; and

said method of fabricating an ultrasonic coupler further comprising the steps of

attaching the connecting member to the first die at the corresponding positions of attachment,

placing the second die over the first die, and

pouring of the aqueous solution into the die;

wherein during the freezing and defrosting of the poured aqueous solution, the connecting member connects to the ultrasonic coupler formed from the aqueous solution.

15. The method of fabricating an ultrasonic coupler according to claim 10, wherein:

said step of fabricating a first die includes forming the first die in a T-shape and forming a pouring inlet in the first die; and

said method of fabricating an ultrasonic coupler further comprising the steps of

attaching the connecting member to the first die,

placing the first die over the second die, and

ceasing the pouring of the aqueous solution into the die when the aqueous solution reaches the lowest extending portion of the first die after the first die is placed over the second die;

wherein during the freezing and defrosting of the poured aqueous solution, the connecting member connects to the ultrasonic coupler formed from the aqueous solution.

16. The method of fabricating an ultrasonic coupler according to claim 10, wherein only the first die, and not the second die, is flexible.