Expansion tube joint and assembling method thereof

Details Expansion tube joint and assembling method thereof Expansion tube joint and assembling method thereof

1999-09-09

2001-10-23

Hook, James (Department: 3752)

Pipes and tubular conduits

Flexible

Joined sections

C138S114000, C138S155000, C285S302000, C285S031000, C285S145300, C285S145400, C285S123130, C285S402000

Reexamination Certificate

active

06305426

ABSTRACT:

BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to an expansion tube joint and an assembling method thereof.
2. Description of the Related Art
Expansion tube joints are widely used in water pipes and the like. There is a conventional expansion tube joint as shown in FIG.
10
. This expansion tube joint comprises a first cylindrical body
1
, and a second cylindrical body
2
inserted into the first cylindrical body
1
along the axis X thereof A T-shaped rubber ring
3
(corresponding to a seal member) is provided between the first and second cylindrical bodies
1
and
2
(between an inner periphery of the first cylindrical body
1
and an outer periphery of the second cylindrical body
2
). The second cylindrical body
2
is extendable relative to the first cylindrical body
1
, and the relative movement range in the axial direction X is limited by a lock mechanism in the expanding and contracting direction.
The lock mechanism will be explained. A stopper in the contracting direction comprises an inner wall projection
1
a
of the first cylindrical body
1
, and an outer wall projection
2
a
of the second cylindrical body
2
. A stopper in the extending direction comprises a stopper ring
4
mounted to an insertion port of the first cylindrical body
1
and the outer wall projection
2
a.
That is, the lock mechanism is formed closer to the insertion port of the first cylindrical body
1
, and the seal member is disposed deeper than the lock mechanism.
With this structure, in a state where the second cylindrical body
2
is inserted into the first cylindrical body
1
deepest, the second cylindrical body
2
must have extra length L from the T-shaped rubber ring
3
. The reason why the second cylindrical body
2
must have the extra length L is that when the second cylindrical body
2
moves in the extending direction (rightward in
FIG. 10
) from a state shown in
FIG. 10
, the seal function by the T-shaped rubber ring
3
must be secured,
Since the length of the second cylindrical body
2
must be secure, the length of the expansion tube joint in the axial direction becomes long, the weight is increased, and the size is also increased. Therefore, there is a problem that costs for producing, storing and transferring the expansion tube joint are increased.
The present invention has been accomplished in view of the above circumstances, and it is an object of the present invention to provide a technique capable of shortening the length of the second cylindrical body as compared with the prior art, and capable of reducing the weight and size of the expansion tube joint to reduce the costs.
SUMMARY OF THE INVENTION
To achieve the above object, an expansion tube joint of the present invention comprises a first cylindrical body, a second cylindrical body inserted along an axis of the first cylindrical body, a seal member mounted between the first and second cylindrical bodies closer to an insertion port of the first cylindrical body, a lock mechanism provided at a position deeper than the seal member for restricting a relative movement range along the axis of the first and second cylindrical bodies, and a coming-out preventing member for preventing the seal member from coming out from the insertion port of the first cylindrical body, wherein after a member constituting the lock mechanism is mounted, the seal member can be mounted.
According to this structure, the seal member is mounted closer to the insertion port of the first cylindrical body, and the lock mechanism is disposed at a deep position. In the prior art, a portion of the second cylindrical body to be inserted into the first cylindrical body must have a length shown with L in
FIG. 10
in addition to a length of a portion constituting the lock mechanism. However, with the above structure, the length L is unnecessary. As a result, the length of the second cylindrical body can be shortened as compared with the prior art, the weight, size and cost of the expansion tube joint can be reduced. After the member constituting the lock mechanism is mounted, the seal member can be mounted. With this structure, the expansion tube joint of the present invention can be assembled. By providing the seal member closer to the insertion port, the seal member can be prevented from coming out by using the coming-out preventing member.
According to a preferred embodiment, the insertion port of the first cylindrical body is formed with a male or female bayonet type engaging portion, and the coming-out preventing member is also formed with a male or female bayonet type engaging portion which can engage the engaging portion of the insertion port.
With this structure, it is possible to mount the seal member such that it does not come out toward the insertion port by a simple operation that the coming-out preventing member and a bayonet of the first cylindrical body engage each other. Whether the male bayonet type or female bayonet type is used each in the coming-out preventing member and the first cylindrical body can be appropriately chosen.
According to another preferred embodiment, the seal member has a self seal function. The self seal function is a function which is applied in a compressing direction of the seal member to seal the flowing out water when water pressure is applied to the seal member. With this structure, it is possible to reliably exhibit the function as an expansion tube joint.
According to another preferred embodiment, the expansion tube joint further comprises temporarily means which fixes movements of the first and second cylindrical bodies but the fixed state is first released to restore extending and contracting function of the tube joint when an excessive force is applied.
With this structure, the original extending and contracting flexibility can be maintained, the assembling structure of the tube joint is not varied easily during transportation, and a tube joint which is easy to handle can be provided, which is convenient.
To achieve the above object, in a assembling method of an expansion tube joint of the invention comprising a first cylindrical body, a second cylindrical body inserted along an axis of the first cylindrical body, a seal member mounted between the first and second cylindrical bodies, and a lock mechanism provided for restricting a relative movement range along the axis of the first and second cylindrical bodies, the seal member being mounted closer to an insertion port of the first cylindrical body, the lock mechanism being provided at a position deeper than the seal member, the method comprises:
a step (1) for inserting the second cylindrical body into the first cylindrical body along the axis in a state where a member constituting the lock mechanism is mounted to the second cylindrical body,
a step (2) for mounting a member constituting the lock mechanism is mounted to the first cylindrical body,
a step (3) for mounting the seal member closer to the insertion port of the first cylindrical body, and
a step (4) for mounting a coming-out preventing member for preventing the seal member from coming out from the insertion port.
This assembling method of the expansion tube joint of this structure includes the steps (1) to (4). In this expansion tube joint used in the assembling method, the seal member is mounted closer to the insertion port of the first cylindrical body, and the lock mechanism is disposed at a deep position. In the prior art, a portion of the second cylindrical body to be inserted into the first cylindrical body must have a length shown with L in
FIG. 10
in addition to a length of a portion constituting the lock mechanism. However, with the above structure, the length L is unnecessary as described above. As a result, the length of the second cylindrical body can be shortened as compared with the prior art, the weight, size and cost of the expansion tube joint can be reduced.
According to a preferred embodiment, when the seal member is mounted, a jig for defining an insertion amount of the seal member from the insertion port of the first cylindrica

Affiliated with

Also associated with

Rating

Expansion tube joint and assembling method thereof does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Expansion tube joint and assembling method thereof, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Expansion tube joint and assembling method thereof will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2616895