Joint structure, joint unit and assembly method of joint unit

Patent metadata

Field	Value
Publication number	US-12331864-B2
Application number	US-202017032451-A
Country	US
Kind code	B2
Filing date	Sep 25, 2020
Priority date	Oct 2, 2019
Publication date	Jun 17, 2025
Grant date	Jun 17, 2025

Abstract

Provided is a joint structure comprising a main body, a tubular part that is formed in a tubular shape to protrude from the main body along an axis and holds an outer peripheral surface of the resin-made tube, and a protrusion that is formed in a shaft shape to protrude from the main body along the axis and forms, between the protrusion and the tubular part, an insertion groove in which the resin-made tube is inserted, the main body and the protrusion are formed with a coupling channel extending along the axis and coupling a liquid transferring channel and another channel, and a tip of the protrusion is disposed at a position closer to the main body than a tip of the tubular part.

First claim

What is claimed is:

1. A joint unit including a resin-made tube in which a liquid transferring channel extending along an axis is formed and a cross section orthogonal to the axis is round and a joint structure attached to an end of the resin-made tube, the joint structure comprising:
a main body;
a tubular part that is formed in a tubular shape integrally protrudes from and is formed unitary with the main body along the axis and has an inner diameter with an inner peripheral surface that holds an outer peripheral surface of the resin-made tube; and
a protrusion that is formed in a shaft shape integrally protrudes from and is formed unitary with the main body along the axis and forms, between the protrusion and the tubular part, an insertion groove in which the resin-made tube is inserted, with the protrusion also being inserted into the liquid transferring channel of the resin-made tube, the main body, the tubular part and the protrusion being a unitary one piece structure, wherein
the main body and the protrusion are formed with a coupling channel extending along the axis and coupling the liquid transferring channel and another channel,
a tip of the protrusion is disposed at a position closer to the main body than a tip of the tubular part,
the protrusion includes a constant diameter shaft portion extending for at least a majority of a length of the insertion groove, and a tip portion having an outer diameter that gradually decreases toward the tip of the protrusion, and
the tubular part has a constant inner diameter in a region from a base of the protrusion to the tip of the protrusion along the axis and has a shape in which an inner diameter expands at the tip of the tubular part in a region from the tip of the protrusion to the tip of the tubular part along the axis,
wherein
an outer diameter of the protrusion is larger than an inner diameter of the liquid transferring channel, an outer diameter of the resin-made tube is smaller than an inner diameter of the tubular part, and the tubular part is disposed on an outer peripheral side of the protrusion in a non-inserted state when the protrusion is not inserted in the liquid transferring channel of the resin-made tube, wherein insertion of the protrusion into the liquid transferring channel of the resin-made tube expands size of the outer peripheral surface of the resin-made tube over the constant diameter shaft portion to form an expanded cylindrical surface extending for at least a majority of the length of the insertion groove to be securely held by the inner peripheral surface of the tubular part disposed on an outer peripheral side of the protrusion.

2. The joint unit according to claim 1 , wherein a length of the protrusion along the axis is three times or more as large as an outer diameter of the protrusion.

3. The joint unit according to claim 1 , wherein a length from the tip of the protrusion to the tip of the tubular part is 0.2 times or more as large as an inner diameter of the tubular part.

4. The joint unit according to claim 1 , wherein
the outer diameter of the resin-made tube is three times or more and 15 times or less as large as an inner diameter of the resin-made tube,
the inner diameter of the resin-made tube is 0.1 mm or more and 1.0 mm or less, and
a thickness of the resin-made tube is equal to a distance between the inner peripheral surface of the tubular part and an outer peripheral surface of the protrusion, or slightly smaller than the distance between the inner peripheral surface of the tubular part and the outer peripheral surface of the protrusion.

5. The joint unit according to claim 1 , wherein the main body is formed of a resin material integrally with the tubular part and the protrusion.

6. The joint unit according to claim 1 , wherein a length of the protrusion along the axis is longer than a length from the tip of the protrusion to the tip of the tubular part along the axis.

7. An assembly method of a joint unit comprising a resin-made tube in which a liquid transferring channel extending along an axis is formed and a cross section orthogonal to the axis is round, and a joint structure attached to an end of the resin-made tube, the joint structure comprising:
a main body,
a tubular part that is formed in a tubular shape integrally protrudes from and is formed unitary with the main body along the axis and has an inner diameter with an inner peripheral surface that holds an outer peripheral surface of the resin-made tube, and
a protrusion that is formed in a shaft shape integrally protrudes from and is formed unitary with the main body along the axis and forms, between the protrusion and the tubular part, an insertion groove in which the resin-made tube is inserted, with the protrusion also being inserted into the liquid transferring channel of the resin-made tube, the main body, the tubular part and the protrusion being a unitary one piece structure, wherein
an outer diameter of the protrusion is larger than an inner diameter of the liquid transferring channel,
an outer diameter of the resin-made tube is smaller than an inner diameter of the tubular part, and the tubular part is disposed on an outer peripheral side of the protrusion in a non-inserted state when the protrusion is not inserted in the liquid transferring channel of the resin-made tube,
a tip of the protrusion is disposed at a position closer to the main body than a tip of the tubular part,
the protrusion includes a constant diameter shaft portion extending for at least a majority of a length of the insertion groove, and a tip portion having an outer diameter that gradually decreases toward the tip of the protrusion, and
the tubular part has a constant inner diameter in a region from a base of the protrusion to the tip of the protrusion along the axis and has a shape in which an inner diameter expands at the tip of the tubular part in a region from the tip of the protrusion to the tip of the tubular part along the axis,
the method comprising:
an applying step of applying an adhesive to at least one of an outer peripheral surface of the end of the resin-made tube and an inner peripheral surface of the tubular part,
an insertion step of inserting the resin-made tube into the tubular part and the protrusion in the liquid transferring channel of the resin-made tube, wherein insertion of the protrusion into the liquid transferring channel of the resin-made tube expands size of the outer peripheral surface of the resin-made tube over the constant diameter shaft portion to form an expanded cylindrical surface extending for at least a majority of the length of the insertion groove to be securely held by the inner peripheral surface of the tubular part disposed on an outer peripheral side of the protrusion, and
a bonding step of curing the adhesive applied in the applying step, and bonding the outer peripheral surface of the resin-made tube in which the protrusion is inserted in the insertion step and the inner peripheral surface of the tubular part.

8. The assembly method according to claim 7 , wherein
the outer diameter of the resin-made tube is three times or more and 15 times or less as large as an inner diameter of the resin-made tube,
the inner diameter of the resin-made tube is 0.1 mm or more and
a thickness of the resin-made tube is equal to a distance between the inner peripheral surface of the tubular part and an outer peripheral surface of the protrusion, or slightly smaller than the distance between the inner peripheral surface of the tubular part and the outer peripheral surface of the protrusion.

9. The assembly method according to claim 7 , wherein the main body is formed of a resin material integrally with the tubular part and the protrusion.

Assignees

• Surpass Ind Co Ltd

Inventors

• Imai Hiroshi
• Hirai Kazuki

Classifications

• B29C66/71

  characterised by the composition of the plastics material of the parts to be joined (welding bar compositions B29C65/125) · CPC title

• B29C66/5221

  for forming coaxial connections, i.e. the tubular articles to be joined forming a zero angle relative to each other · CPC title

• B29C65/48

  using adhesives {, i.e. using supplementary joining material; solvent bonding} · CPC title

• F16L25/0018

  Abutment joints · CPC title

• F04B43/1253

  by using two or more rollers as squeezing elements, the rollers moving on an arc of a circle during squeezing · CPC title