TITLE
HOSE JOINT
FIELD OF THE INVENTION
[0001] The present invention relates to a hose joint which is used to connect hoses for piping,
the hoses being such as, for example, silicone rubber hoses made soft and easily deformable.
Specifically, it relates that the hose is inserted along an outer peripheral surface of a nipple, the
inner peripheral surface adhered tightly to the outer peripheral surface of the nipple along with a
chuck tightener provided outside, moving in an axial direction.
BACKGROUND OF THE INVENTION
[0002] In the prior art, this type of hose joints include a nut connected to a second joint
configured as a nipple; a front ring placed on a back inner peripheral surface of a female thread of
the nut and interposed between the back inner peripheral surface and an outer peripheral surface
of a hose tip; a back ring separated from the front ring by a predetermined gap and interposed
between a rear end inner peripheral surface of the nut and the outer peripheral surface of the
hose; and an insert sleeve which is inserted into the inner peripheral surface of the hose end
portion side in a state of being connected to the second joint and, which pinches the inner and
outer peripheral surfaces of the hose end portion side together with the front ring or the back ring
(for example, see Patent Literature 1). During connecting the hose with the hose joint, firstly, in
the state of engaging the back ring with the nut, the back ring and the nut are inserted together
into the outer periphery of the hose and arranged at the back, and then, after inserting the insert
sleeve into a terminal of the hose, the insert sleeve is fitted into the second joint, and the front ring
fitted into the outer periphery of the hose terminal is fitted into the second joint. Moreover, by
screwing the nut to the second joint, the back ring is drawn toward the front ring side. When the
outer periphery of the hose is fitted onto an annular convex portion of the insert sleeve or both
curved slope surfaces thereof and securely pinched by the front ring or the back ring in a radial
direction, a portion bulged and deformed in the radial direction by the annular convex portion is
simultaneously pinched in the axial direction by the front ring or the back ring.
PATENT LITERATURE
[0003]
[PATENT LITERATURE 1] Japanese registered Utility Model No. 3088531
PROBLEMS TO BE SOLVED BY THE INVENTION
[0004] However, in such a conventional hose joint, the nut cannot be screwed unless fitting the
front ring following to the hose terminal into the insert sleeve and then fitting the insert sleeve into
the second joint. Thus, there is a problem that a hose cannot be connected in a short time since

connecting a hose is an arduous task and its workability is poor. Furthermore, since a gap is
formed between a continuous hole formed in the inner periphery of the insert sleeve and a
continuous hole of the second joint by fitting the insert sleeve into the second joint, liquids are
stagnated for fluids entered into the gap, and unhygienic condition is easily caused. Furthermore,
since a fitting barrel outer periphery of the insert sleeve fits into a large-diameter stepped-fitting
hole of the second joint via an O ring with cohesive liquids, and the fluids entered into the gap
between the continuous holes of the insert sleeve and the second joint also contacts
(liquids-contact) with the 0 ring, there is also a problem that unhygienic condition can be easily
caused, and the use thereof is limited. Thus, by integrating the insert sleeve with the second joint
in advance, inserting the hose along the annular convex portion of the insert sleeve and fitting the
hose terminal into the front ring kept in a place, it is considered to reduce a process up to screwing
the nut and to choose a type and an application of fluids regardless the problem liquids are
stagnated in the middle of the continuous path or liquids contact with the O ring, or the like.
However, in this case, since the front ring is formed with its inner diameter approximately same as
the outer diameter of the hose, it is difficult to fit the hose terminal into the front ring by just
pushing the hose, and there is a concern that the nut may be screwed without the hose not reliably
pushed in a place. In this manner, when the nut is screwed without the hose terminal fitted into
the front ring, there is a problem that an unreliable connection results in decreasing the sealing
performance between the outer peripheral surface of the insert sleeve and the hose and the
stability not to slip out.
[0005] The present invention is intended to address such problems, and it is objective to
increase and improve further the sealing performance between the outer peripheral surface of the
nipple and the hose and the stability not to slip out by stabilizing at a place where the hose tip is
pushed into, to reliably pinch the hose in the axial and the radial directions, to reliably insert the
hose in a place, and the like.
SOLUTIONS TO PROBLEMS
[0006] To reach the objective, the present invention provides a hose joint that a hose is inserted
along an outer peripheral surface of a nipple, the outer peripheral surface of a nipple tightly
adhering to an inner peripheral surface of the hose along with a chuck tightener provided outside
of the hose, moving in an axial direction. The hose joint includes an annular bulging part formed
on the outer peripheral surface of the nipple, the diameter of the annular bulging part gradually
enlarged up to maximum then gradually shrunk along with the hose inserted further, an
expandable sleeve elastically-deformable in a radial direction opposite to a back side outer
peripheral surface, arranged at and beyond the back of a contracting diameter tapered surface of
the bulging part in the hose insertion direction, and a pressure surface part formed inside of the
chuck tightener, opposite to the outer peripheral surface of the expandable sleeve, the pressure

surface part pressing the expandable sleeve so as to shrink by the diameter along with the chuck
tightener moving relative to the nipple in an axial direction. The nipple includes a back side outer
peripheral surface formed at back beyond the contracting diameter tapered surface of said bulging
part in the hose insertion direction, an annular step part protruded and formed at further back
than said back side outer peripheral surface in the hose insertion direction and a cylindrical part
formed outside of said annular step part, opposite to the back side outer peripheral surface. The
expandable sleeve includes an inlet part formed so as to be opposite to said contracting diameter
tapered surface, a cylindrical expandable part having an inner peripheral surface formed so as to be
gradually enlarged as being in a opposite direction to the hose insertion at a further back than the
inlet part in the hose insertion direction at inserting said hose, a slitting notched so as to stretch
toward said inlet part and said cylindrical expandable part in an axial direction, enabling said inlet
part and said cylindrical expandable part elastically-deformable in a radial direction, an annular
flange formed along said annular step part from the hose insertion direction inner side end of said
cylindrical expandable part toward said back side outer peripheral surface, and a stopper
protruded and formed so as to touch and contact with the outer peripheral surface of said
cylindrical expandable part, opposite to a tip edge of said cylindrical part. Inner diameters of said
inlet part and said cylindrical expandable part are set greater than the outer diameter of said hose
inserted along the contracting diameter tapered surface of said bulging part when said hose is
being inserted and are set smaller than the outer diameter of said hose inserted along the
contracting diameter tapered surface of said bulging part when said pressure surface part is
pressing said expandable sleeve with said chuck tightener moving further in an axial direction, and
an axial distance between said stopper and said annular flange is set same as between the tip edge
of said cylindrical part and said annular step part.
[0007] In addition to the above description, an annular convex part is formed at an inlet part of
the expandable sleeve opposite to the outer peripheral surface of the hose. The inner diameter
of the annular convex part is set greater than the outer diameter of the hose inserted along the
contracting diameter tapered surface of the bulging part when the hose is inserted, and it is set
smaller than the outer diameter of the hose inserted along the contracting diameter tapered
surface of the bulging part when the pressure surface part presses the expandable sleeve along
with the chuck tightener moving further in the axial direction.
[0008] Further in addition to the above described, a pressure tube part is formed opposite to the
expanding diameter tapered surface of the bulging part on the inner peripheral surface of the
chuck tightener along with the chuck tightener moving further in the axial direction, as separated
or integrated, and an engagement concave part is formed opposite to an annular space formed
between the hose insertion direction side end surface of the pressure tube part and a counter-hose

insertion direction side end surface of the expandable sleeve in a state of the chuck tightener
tightened moving in the axial direction.
[0009] Also in addition to the above described, the annular flange opposite to the tip surface of
the hose is formed toward the back of the outer peripheral surface of the nipple at the end part of
the expandable sleeve in the hose insertion direction.
ADVANTAGES OF THE INVENTION
[0010] The characteristics of the present invention, mentioned above, allow, when the hose is
inserted, to set an inner diameter of an inlet portion opposite to a contracting diameter tapered
surface of an expandable sleeve greater than an outer diameter of the hose inserted along a
contracting diameter tapered surface of a bulging part, to thereby smoothly insert a tip part of the
hose between the expandable sleeve and the contracting diameter tapered surface in a place
without stinging the inlet portion of the expandable sleeve . Then, when a pressure surface part
is pressed and pressured along with a chuck tightener moving in an axial direction , by the inner
diameter of the inlet portion of the expandable sleeve set smaller than the outer diameter of the
hose inserted along the diameter contacted surface of the bulging part and the hose interposed
between the inlet portion of the expandable sleeve and the contracting diameter tapered surface
of the nipple, it is possible to stabilize at a place where the hose tip is pushed into and increase the
sealing performance and stability not to slip out between the outer peripheral surface of the nipple
and the hose. As a result, the workability to connect the hose is improved, whereby anyone can
perform the work to connect the hose, simply, quickly, and reliably. Furthermore, while a gap
occurs in the middle of the continuous path in the conventional horse, the present invention
prevents liquid stagnation, liquid contact with the O ring or the like to occur in the middle of the
continuous path formed along the inner peripheral surface of the nipple, and the hose joint of the
present invention is sanitary and flexible to use regardless the type of fluids or the application.
[0011] Further, in the event that an annular convex part is formed at an inlet part of the
expandable sleeve opposite to the outer peripheral surface of the hose, an inner diameter of the
annular convex part is set greater than the outer diameter of the hose inserted along the
contracting diameter tapered surface of the bulging part when the hose is being inserted and is set
smaller than the outer diameter of the hose inserted along the contracting diameter tapered
surface of the bulging part when the pressure surface part presses the expandable sleeve along
with the chuck tightener moving further in an axial direction, the hose is smoothly inserted among
the inner peripheral surface, the contracting diameter tapered surface and the back side outer
peripheral surface of the expandable sleeve 3 without the tip part of the hose H blocked by the
annular convex part becoming an inlet part of the expandable sleeve, and then the sealing
performance and stability not to slip out between the outer peripheral surface of the nipple and
the hose may be further improved since the hose is more strongly interposed between the

contracting diameter tapered surface of the nipple and the outer peripheral surface of the hose
into which the annular convex part penetrates while the hose is interposed between the inner
peripheral surface of the expandable sleeve contracted and deformed and the back outer
peripheral surface of the nipple in the radial direction when pressured by the pressure surface part
along with the chuck tightener moving further.
[0012] Also, in the event that a pressure tube part is formed opposite to the expanding diameter
tapered surface of the bulging part on the inner peripheral surface of the chuck tightener along
with the chuck tightener moving further in an axial direction, as separated or integrated, and an
engagement concave part is formed opposite to an annular space formed between the hose
insertion direction side end surface of the pressure tube part and a counter-hose insertion
direction side end surface of the expandable sleeve in a state of the chuck tightener tightened by
moving in an axial direction while the hose is interposed between the expanding diameter tapered
surface of the bulging part and the pressure tube part in the radial direction along with the chuck
tightener moving further, therewith the outer peripheral surface of the hose is bulged and
deformed into annular space formed between the hose insertion direction side end surface of the
pressure tube part and the counter-hose insertion direction side end surface of the expandable
sleeve toward the engagement concave part, thereby the outer peripheral surface of the bulged
and deformed hose is pressured and contacted by adhering along the engagement concave part,
and the hose can be reliably pinched in the axial and the radial directions. As a result, particularly
even in the case the hose is soft and easily deformable, for example, such as silicone hoses, the
hose is securely prevented from slipping out because deformation of the hose helps to improve the
sealing performance and the stability not to slip out.
[0013] In addition, when the annular flange opposite to the end surface of the hose is formed
to direct toward the back side outer peripheral surface of the nipple in the end portion of the
expandable sleeve in the hose insertion direction, by setting the expandable sleeve against the
back side outer peripheral surface of the nipple, an insertion space of the hose is formed between
the back side outer peripheral surface and the inner peripheral surface of the expandable sleeve;
the end surface of the hose being inserted collides against the annular flange of the expandable
sleeve; the hose H cannot move into further; and the hose can be reliably inserted in a place.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] Fig. 1 is a longitudinal cross-sectional front view showing a hose joint according to an
embodiment of the present invention, (a) illustrates a state before the hose is inserted, (b)
illustrates a state after the hose is inserted, (c) illustrates a state when a movement of a chuck
tightener is started, and (d) illustrates a state after the movement of the chuck tightener is
finished.

Fig. 2 is a perspective view of the hose joint, (a) illustrates a state before the hose is inserted, (b)
illustrates a state after the hose is inserted, (c) illustrates a state when a movement of a chuck
tightener is started, and (d) illustrates a state after the movement of the chuck tightener is
finished.
Fig. 3 is a longitudinal cross-sectional front view showing a disassembled state of the host joint
according to an embodiment of the present invention.
Fig. 4 is a perspective view of the hose joint, (a) illustrates an entire disassembled state, and (b)
illustrates a state when only an expandable sleeve is viewed from the opposite direction.
DESCRIPTION OF THE INVENTION
[0015] An embodiment of a hose joint A of the present invention includes, as shown in Figs. 1
to 4, a nipple 1 into which a connection end portion of a flexible hose H is inserted, a chuck
tightener 2 provided so as to axially freely reciprocate with respect to the nipple 1, and an
expandable sleeve 3 placed on an outer peripheral surface of the nipple 1 via the connection end
portion of the hose H. By moving the chuck tightener 2 in the axial direction, for example, an
insertion direction (hereinafter, referred to as the hose insertion direction) of the hose H to
contract the diameter of the expandable sleeve 3 after the connection end of the hose H is inserted
into the outer peripheral surface of the nipple 1, an inner peripheral surface H1 of the connection
end portion of the hose H adheres to the outer peripheral surface of the nipple 1, thereby
connecting the hose H as not to slip out.
[0016] The nipple 1 is shaped in cylindrical with an outer diameter being approximately the
same as or slightly greater than the inner diameter of the hose H, made of a metal, for example,
such as bronze or a rigid material such as a rigid synthetic resin, or pressed or molded in other ways
with a plate material made of, for example, an easily shapeable rigid material such as stainless steel
and shaped in cylindrical with a thin wall. An annular bulging part la is formed around an outer
peripheral surface of the nipple 1, the annular bulging part la having a diameter expanding
gradually in the hose insertion direction, and contracting gradually from the maximum diameter
portion.
[0017] An expanding diameter tapered surface 1a1 and a contracting diameter tapered surface
la2 are continuously arranged at the annular bulging portion la, the expanding diameter tapered
surface lal gradually expanding from a tip edge lb of an opposite direction (hereinafter, referred
to as a counter-insertion direction) of the hose insertion direction of the nipple 1 in the hose
insertion direction, the contracting diameter tapered surface la2 gradually contracting from a
maximum diameter portion of the expanding diameter tapered surface 1a1 in the hose insertion
direction, and they form a taper surface which is inclined linearly in the examples shown in Figs. 1
to 4 but may be also inclined in a curved shape in another example. On an inner side beyond the
contracting diameter tapered surface 1a2 of the bulging portion 1a in the hose insertion direction,

an back side outer peripheral surface 1c having the same diameter as a minimum diameter portion
of the diameter contacted surface la is formed in the hose insertion direction by a predetermined
length.
[0018] On a tip inner peripheral surface of the nipple 1, a counter-taper surface 1d is formed
which gradually expands toward the tip thereof. In the example shown in Fig. 1(d), it is preferable
that, by projecting a pressure tube part 4 described later beyond the tip edge lb of the nipple 1 in a
tightened state by the chuck tightener 2 described later, the hose H be pushed inward by the
pressure tube portion 4, and an inner end portion thereof be placed so as to be continued with the
counter-taper surface 1d of the nipple 1.
[0019] Furthermore, on the inner side in the hose insertion direction rather than the back side
outer peripheral surface 1c of the nipple 1, an annular step portion 1e nearly vertically projected
from the back side outer peripheral surface 1c is integrally formed. On the outside of the annular
step portion 1e, slide means 1f for supporting the chuck tightener 2 described later in the hose
insertion direction and the counter-hose insertion direction which is opposite to the hose insertion
direction in a freely reciprocating manner is formed. In addition, it is desirable to form a plurality
of plane portions with which a tool or the like is engaged in a circumferential direction for each
suitable interval, for example, like the examples shown in Figs. 2 and 4, or to additionally form
concave and convex portions such as a knurling tool, as anti-slip means for rotation operation 1g in
the outer peripheral surface of the nipple 1.
[0020] For example, the chuck tightener 2 is formed in an approximately cylindrical shape
having an inner diameter greater than an outer diameter of the hose H by the same material as the
nipple 1 or a material different from the nipple 1. On the inner peripheral surface thereof, slide
means 2a for being engaged with the slide means 1f of the nipple 1 and supporting the slide means
1f in the hose insertion direction and the counter-insertion direction in a freely reciprocating
manner is formed. As the slide means 1f of the nipple 1 and the slide means 2a of the chuck
tightener 2, it is preferable to form a thread which relatively reciprocates in the hose insertion
direction and the counter-insertion direction by relatively rotating and operating the chuck
tightener 2 relative to the nipple 1. In addition, as another example, it is also possible to perform
an interlocking fitting of the nipple 1 and the chuck tightener 2 and immovably engage both of
them with each other, by bringing them into plane-contact with each other, and moving them in
the hose insertion direction.
[0021] In addition, on the inside of the chuck tightener 2, means for pressing a cylindrical
expandable part 3e of the expandable sleeve 3 described later in the radial direction along with the
movement in the axial direction of the chuck tightener 2 with respect to the nipple 1 to reduce the
diameter thereof is provided. As the sleeve diameter reducing means, it is preferable to directly
form a pressure surface part 2b inclined in a taper shape having an inner diameter gradually

reduced toward the counter-insertion direction, on the inner peripheral surface of the chuck
tightener 2. Furthermore, as another example, it is also possible to provide a pressing sleeve
inside (the inner periphery) of the chuck tightener 2 in a freely rotatable manner, and to form the
inner peripheral surface of the pressing sleeve as the pressure surface part inclined in a taper shape
having an inner diameter gradually reduced toward the counter-insertion direction to face the
outer peripheral surface of the cylindrical expended part 3e of the expandable sleeve 3 described
later.
[0022] On one end side in the inner peripheral surface of the chuck tightener 2 in the
counter-insertion direction, a pressure tube part 4 formed so as to face the expanding diameter
tapered surface 1a1 of the bulging part la along with the axial movement of the chuck tightener 2
is preferably provided separately or integrally. In the tightened state due to the axial movement
of the chuck fastener 2, an engagement concave part 2c is preferably formed so as to face an
annular space S formed between a hose insertion direction side end surface of the pressure tube
part 4, that is, an inner side end surface 4a and the counter hose-insertion direction side end
surface of the expandable sleeve 3 described later, that is, an inlet side end surface 3b.
[0023] Furthermore, on the outer peripheral surface of the chuck tightener 2, as non-slip
means for rotation operation 2d, for example, like an example shown in Figs. 2 and 4, it is
preferable to form a plurality of plane parts, with which a tool or the like is engaged for each
suitable interval in the circumferential direction, or to form a concave and convex part such as a
knurling tool.
[0024] The expandable sleeve 3 is formed in a substantially cylindrical shape by an elastically
deformable material such as polyacetal resin or other synthetic resin excellent in heat resistance
and slippage of surface. The expandable sleeve 3 is arranged so as to face the contracting
diameter tapered surface la2 and the back side outer peripheral surface 1c of the nipple 1 by being
inserted into the annular step portion 1e of the nipple 1. Particularly, a portion of a side opposite
to the hose insertion direction facing the contracting diameter tapered surface 1a2 is formed as an
inlet part 3a. In addition, as shown in Figs. 1A to 1C, the expandable sleeve 3 is expanded and
deformed at the time point before the insertion of the hose H and during insertion. An inner
diameter of at least the inlet part 3a is set to be greater than an outer diameter of the hose H to be
inserted along the contracting diameter tapered surface 1a2 of the bulging part la. Furthermore,
as shown in Fig. 1D, when being pressed and pressured by the pressure surface part 2b along with
the axial movement of the chuck tightener 2, the expandable sleeve 3 is subjected to the diameter
contraction deformation. The inner diameter of the inlet portion 3a is set so as to be smaller than
the outer diameter of the hose H inserted along the contracting diameter tapered surface 1a2 of
the bulging part 1a.

[0025] According to the hose joint A, when the hose H is inserted, as shown in Figs. 1A and 1B,
a tip part of the hose H smoothly enters between the expandable sleeve 3 and the contracting
diameter tapered surface 1a2 without colliding with the inlet part 3a of the expandable sleeve 3
and can be inserted up to a fixed position. After that, when the hose H is pressed by the pressure
surface part 2b along with the axial movement of the chuck tightener 2, as shown in Fig. 1D, the
expandable sleeve 3 is subjected to the diameter contraction deformation, and the hose H is
interposed between the inlet part 3a and the contracting diameter tapered surface of the nipple 1
in the radial direction.
[0026] At this time, when the pressure tube part 4 is provided separately or integrally on the
inner peripheral surface of the chuck tightener 2, the hose H is interposed between the expanding
diameter tapered surface 1a1 of the bulging part 1a and the pressure tube part 4 by the axial
movement of the chuck tightener 2. Along with this and at the same time, the outer peripheral
surface H2 of the hose H is subjected to the bulging deformation toward the engagement concave
part 2c through the annular space S which is formed between the hose insertion direction side end
surface (the inner side end surface) 4a of the pressure tube part 4 and the counter hose-insertion
direction side end surface (the inlet side end surface) 3b of the expandable sleeve 3. As a result,
the outer peripheral surface H2 of the hose H subjected to the bulging deformation adheres along
the engagement concave part 2c and is pressed against the same.
[0027] Describing in more detail, the expandable sleeve 3 is formed so that the diameter
thereof gradually expands in the counter-insertion direction, a slitting 3c extended in the axial
direction is notched, and the expandable sleeve 3 can be elastically deformed in the radial direction.
The inlet part 3a is formed with an annular convex part which faces the outer peripheral surface H2
of the hose H, and the inner diameter of the annular convex part is set to be greater than the outer
diameter of the hose H inserted along the contracting diameter tapered surface la2 of the bulging
part la before and during the insertion of the hose H. Furthermore, when the expandable sleeve
3 is pressed by the pressure surface part 2b along with the axial movement of the chuck tightener 2,
the inner diameter of the annular convex part is set to be smaller than the outer diameter of the
hose H inserted along the contracting diameter tapered surface 1a2 of the bulging part la. That is,
the inner diameter of the expandable sleeve 3 in the inner side of the hose insertion direction is set
to be substantially the same as the outer diameter of the hose H inserted along the contracting
diameter tapered surface 1b2 of the bulging part lb. When the expandable sleeve 3 is pressed by
the pressure surface part 2b along with the axial movement of the chuck tightener 2, the annular
convex part becoming the inlet part 3a penetrates into the outer peripheral surface H2 of the hose
H, and the other inner peripheral surface 3d is pressed against outer peripheral surface H2 of the
hose H.

[0028] According to the hose joint A, when the hose H is inserted, as shown in Figs. 1A and 1B,
the hose H is smoothly inserted between the contracting diameter tapered surface 1a2 of the inner
peripheral surface 3d of the expandable sleeve 3 and the back side outer peripheral surface 1c of
the nipple 1 such that the tip part of the hose H does not collide with the annular convex part
becoming the inlet part 3a of the expandable sleeve 3. After that, when the expandable sleeve 3
is pressed by the pressure surface part 2b along with the axial movement of the chuck tightener 2,
as shown in Fig. 1D, the expandable sleeve 3 is subjected to the diameter contraction deformation,
and the hose H is interposed between the inner peripheral surface 3d and the back side outer
peripheral surface 1c of the nipple 1. At the same time, the annular convex part being an inlet
part 3a penetrates into the outer peripheral surface H2 of the hose H, and is more strongly
interposed between the same and the contracting diameter tapered surface 1a2 of the nipple 1.
Hereinafter, an embodiment of the present invention will be described based on the drawings.
[Embodiment 1]
[0029] As shown in Figs. 1A to 1D, 2A to 2D, 3, 4A and 4B, in Embodiment 1, an external thread
part is engraved as slide means 1f of the nipple 1, an internal thread part is engraved as slide
means 2a of the chuck tightener 2 facing the same. By screwing the external thread part 1f and
the internal thread part 2a each other, performing the rotational operation of the chuck tightener 2
with respect to the nipple 1, and moving the chuck tightener 2 in the hose insertion direction, the
pressure surface part 2b integrally formed on the inner peripheral surface of the chuck tightener 2
presses the inlet part 3a of the expandable sleeve 3 to perform the diameter contraction
deformation thereof.
[0030] As shown in Figs. 4A and 4B, the expandable sleeve 3 includes an annular convex part
becoming the inlet part 3a, a cylindrically expansion and contraction part 3e having a counter-hose
insertion direction side end surface (an inlet side end surface) 3b and an inner peripheral surface
3d, and an annular flange 3f integrally formed from the other end of the hose insertion direction of
the cylindrically expansion and contraction part 3e toward the back side outer peripheral surface 1c
of the nipple 1. The annular flange 3f is used as an end surface of the tip surface (a cutting
surface) H3 of the hose H, and a plurality of slitting 3c is notched in the circumferential direction.
One 3clof the slittings 3c is continuous over the cylindrical expansion and contraction part 3e and
the annular flange 3f, but another metal slitting 3c2 is partially formed in the cylindrically
expansion and contraction part 3e or the annular flange 3f.
[0031] In addition, on the outer peripheral surface of the cylindrically expansion and
contraction part 3e in the expandable sleeve 3, a stopper 3g is integrally formed so as to protrude
which faces a tip edge 1h of the external thread part becoming the slide means 1f of the nipple 1.
Herein, if dimensions are set in advance so that an axial dimension from the stopper 3g to the

annular flange 3f coincides with an axial dimension from the tip edge 1h of the external thread part
1f of the nipple 1 to the annular step part 1e, by bringing the stopper 3g into contact with the tip
edge 1h of the external thread part 1f, the positioning is performed so that the annular flange 3f of
the expandable sleeve 3 comes into contact with the annular step part le of the nipple 1.
Furthermore, at setting the expandable sleeve 3, merely by viewing a position relationship
between the stopper 3g and the tip edge lh of the external thread part 1f, for example, the
loose-jointed condition of them, it is possible to determine whether or not the annular flange 3f is
correctly assembled so as to come into contact with the annular step part le of the nipple 1.
Furthermore, by inserting the tip surface H3 of the hose H while being pushed into the annular
flange 3f of the expandable sleeve 3, and by detecting how loosely jointed between the stopper 3g
and the tip edge lh of the external thread part 1f, it is possible to simply determine that the hose H
is reliably inserted up to a target position , and it is also possible to prevent the expandable sleeve
3from deformed and damaged along with inserting the hose H.
[0032] Moreover, in the embodiment 1, since the chuck tightener 2 rotates relative to the
nipple 1, as the pressure tube part 4 mentioned above, a ring separated from the chuck tightener 2
is used. In the case of an example shown in Fig. 4A, the separate ring used as the pressure tube
part 4having a slitting 4b extended along the entire length in the axial direction and notched is
capable of being elastically-deformable in the radial direction. Taper surfaces 4d and 2e pressing
the separate ring 4 so as to be contracted in diameter are formed on both or any one of the outer
peripheral surface 4c of the ring and the inner peripheral surface of the chuck tightener 2 facing
the same. With the ring contracted the inner diameter is set smaller than the outer diameter of
the hose H inserted along the expanding diameter tapered surface 1a1l of the bulging part la.
Furthermore, as another example, it is also possible to press the hose H by the expanding diameter
tapered surface 1a1 of the bulging part la without deformation of the hose in an inner radial
direction with the pressure tube part 4 molded in a ring shape without slit.
[0033] Furthermore, on the further back side in the hose insertion direction than the external
thread part formed as the slide means 1f of the nipple 1, a connection part 1i to be connected to a
pipe connection port (not shown) of another equipment is subsequently provided.
When an internal thread is engraved on the inner peripheral surface of the pipe connection port
in another equipment connected to the hose joint A, in the connection part 1i, an external thread
is engraved against the internal thread, and when an external thread is engraved on the outer
peripheral surface of the pipe connection port, an internal thread is engraved against the eternal
thread. In the shown example, when the nipple 1 is a cutting product made of a cylindrical
material carved through a cutting working or the like, the external thread is engraved as the
connection part li.

[0034] Meanwhile, the hose H preferably includes flat inner and outer peripherals, H1 and H2,
made from, for example, a soft material such as a soft synthetic resin of a silicon rubber, vinyl
chloride or the like. As a specific example thereof, there are used a laminated hose in which
plural or single braid (a splicing yarn) made of a synthetic resin buried in spirals between outer and
inner layers which are transparent or opaque as an intermediate later,
a spiral reinforced hose in which a band-like reinforcement material made of synthetic resin or
metal having a cross section of a rectangular shape and a filamentous reinforcement material
having a cross section of a circular shape or the like are wound around and integrated in spirals as
an intermediate layer, a braid reinforced hose in which a filamentous reinforcement material such
as, for example, a glass fiber and a fire retardant fiber is braided on the hose outer peripheral
surface, a spiral reinforcement hose in which a metallic wire rod or a wire rod made of a hard
synthetic resin is buried in spirals form and a hose made of a soft synthetic resin of a single layer
structure or the like.
[0035] Next, hereafter, a connecting method of the hose H by a hose joint A is described with
processes in sequence, and a working effect obtained thereby is also described. As shown by a
disassembled state of the hose joint A in Figs. 3, 4A and 4B, and also in Figs. 1A and 2A, firstly, the
expandable sleeve 3 is set relative to the annular step part 1e of the nipple 1 and the back side
outer peripheral surface 1c while climbing over the bulging part la of the nipple 1, and space to
insert the hose H is formed between the backside outer peripheral surface 1c and the inner
peripheral surface 3b of the expandable sleeve 3. Furthermore, the hose H is inserted through
the chuck tightener 2 and a separate ring becoming the pressure tube part 4, and then, the tip part
of the hose H begins to be inserted toward the insertion space of the hose H along the bulging part
la of the nipple 1.
[0036] At this point, because an annular convex part becoming the inlet part 3a of the
expandable sleeve 3 has the diameter expanded and deformed in a radial direction so as to be
greater than the outer diameter of the hose H inserted along the contracting diameter tapered
surface la2 of the bulging part la, the hose is smoothly inserted between the inner peripheral
surface 3d of the expandable sleeve 3 and the back side outer peripheral surface lc of the nipple 1
and the contracting diameter tapered surface la2, the hose H is inserted further without the tip
part of the hose H blocked by the annular convex part. Then, as shown in Figs. 1B and 2B, with
the tip surface H3 of the hose H blocked by the annular step part le of the nipple 1 via the annular
flange 3f of the expandable sleeve 3, the hose H cannot be inserted further.
[0037] Next, even when the chuck tigthtener 2 is moved further in the hose insertion direction,
as shown in Figs. 1C and 2C, with the internal thread part 2a threaded with the external thread part
1f of the nipple 1 and rotated, since the chuck tigthener 2 slips around the separate ring becoming
the pressure tube part 4 without transmitting the rotational force to the hose H via the ring, the

hose H is prevented from twisting. Along with this, since the inner peripheral surface 4e of the
ring strongly comes into contact with the outer peripheral surface H2 of the hose H inserted along
the expanding diameter tapered surface 1a1 of the bulging surface la, the ring is deformed with
the diameter contracted by the taper surfaces 4d and 2c by deviation generated between the inner
peripheral surface of the chuck tightener 2 and the outer peripheral surface 4c of the ring. As a
result, after that, because the inner peripheral surface 4e of the ring is more strongly pressed and
touched the outer peripheral surface H2 of the hose H by the movement of the chuck tightener 2,
force is generated so as to be drawn in the hose insertion direction, and a gap is being gradually
narrowed between the chuck tightener 3 and the counter hose-insertion direction side end surface
(the inlet side end surface) 3b of the expandable sleeve 3.
[0038] In addition, due to the movement of the chuck tightener 2 in the hose insertion
direction, the pressure surface part 2b pressures the cylindrical expandable part 3e of the
expandable sleeve 3 in the diameter direction to touch and contact. Therefore, as shown in Figs.
1D and 2D, the cylindrical expandable part 3e of the expandable sleeve 3 is deformed with the
diameter contracted, the hose H is interposed between the annular convex part becoming the inlet
part 3a and the contracting diameter tapered surface 1a2 of the bulging part 1a, the annular
convex part becoming the inlet part 3a penetrates into the outer peripheral surface H2 of the hose
H, and the inner peripheral surface 3d pressured and contact with the outer peripheral surface
H2 of the hose H. Moreover, at the same time, the inner peripheral surface 4e of the separate
ring becoming the pressure tube part 4 penetrates into the outer peripheral surface H2 of the hose
H, and the hose H is interposed between the expanding diameter tapered surface 1a1 of the
bulging part la and the pressure tube part 4 in the radial direction.
[0039] As a result, the outer peripheral surface H2 of the hose H is bulged and deformed
toward the engagement concave part 2c into the annular space S formed between the hose
insertion direction side end surface (the inner side end surface) 4a of the separate ring becoming
the pressure tube part 4 and the counter-hose insertion direction side end surface (the inlet side
end surface) 3b of the expandable sleeve 3, and the outer peripheral surface H2 of the bulged and
deformed hose H is pressured and contacted by adhering along the engagement concave part 2c.
Particularly, in a case where the hose H is soft and easily deformed, for example, like a silicone
hose, due to the annular convex part becoming the inlet part 3a, the penetration of the inner
peripheral surface 4e of the separate ring becoming the pressure tube part 4 and the
pressure-contact of the inner peripheral surface 3d of the expandable sleeve 3, the outer
peripheral surface H2 of the hose H bulges by the compression, and the hose H is strongly
interposed between the hose insertion direction side end surface (the inner side end surface) 4a of
the ring and the counter-hose insertion direction side end surface (the inlet side end surface) 3b of
the expandable sleeve 3. Thus, hose H is reliably pinched in the axial and the radial directions,

whereby it is possible to increase the sealing performance between the outer peripheral surface of
the nipple 1 and the hose H and the stability not to slip out while stabilizing at the place where the
hose tip is pushed into.
[0040] In addition, in the embodiment mentioned above, as the slide means 1f and 2a which
move the chuck tightener 2 in the axial direction with respect to the nipple 1, the internal thread
part and the external thread part threaded with each other were formed. However, if it is
possible to move the chuck tightener 2 in the axial direction at least with respect to the expandable
sleeve 3, a structure other than the thread may be adopted, without being limited thereto.
EXPLANATION OF SYMBOLS
[0041] 1: nipple
1a: bulging part
1a1 expanding diameter tapered surface
1a2 contracting diameter tapered surface
1c: back side outer peripheral surface
2: chuck tightener
2b pressure surface part
2c: engagement concave part
3 expandable sleeve
3a: inlet part
3b: counter-hose insertion direction side end surface (inlet side end surface)
3c: slitting
3d: inner peripheral surface
3f annular flange
4 pressure tube part
4a: hose insertion direction side end surface (inner side end surface)
H: hose
H1: inner peripheral surface
H2: outer peripheral surface
H3: tip surface

What is claimed is:
1. A hose joint in which a hose is inserted along an outer peripheral surface of a nipple, an inner
peripheral surface of said hose adhered tightly to the outer peripheral surface of said nipple along
with a chuck tightener provided outside, moving in an axial direction, including:
an annular bulging part formed on the outer peripheral surface of said nipple, having an
expanding diameter tapered surface with a diameter being gradually enlarged as the hose is
inserted further till the diameter becomes maximum, and a contracting diameter tapered surface,
with a diameter being gradually shrunk from the diameter becomes maximum ;
an expandable sleeve being elastically-deformable in a radial direction, arranged opposite to a
back side of outer peripheral surface, located at and beyond the contracting diameter tapered
surface in the hose insertion direction; and
a pressure surface part formed inside of said chuck tightener opposite to the outer peripheral
surface of said expandable sleeve, pressing said expandable sleeve so as to shrink the diameter
along with said chuck tightener moving in an axial direction along said nipple,
wherein said nipple includes a back side outer peripheral surface formed at back beyond the
contracting diameter tapered surface of said bulging part in the hose insertion direction,
an annular step part protruded and formed at further back than said back side outer peripheral
surface in the hose insertion direction and a cylindrical part formed outside of said annular step
part, opposite to the back side outer peripheral surface,
said expandable sleeve includes an inlet part formed so as to be opposite to said contracting
diameter tapered surface,
a cylindrical expandable part having an inner peripheral surface formed so as to be gradually
enlarged as being in a opposite direction to the hose insertion at a further back than the inlet part
in the hose insertion direction at inserting said hose,
a slitting notched so as to stretch toward said inlet part and said cylindrical expandable part in an
axial direction, enabling said inlet part and said cylindrical expandable part elastically-deformable in
a radial direction,
an annular flange formed along said annular step part from the hose insertion direction inner side
end of said cylindrical expandable part toward said back side outer peripheral surface, and
a stopper protruded and formed so as to touch and contact with the outer peripheral surface of
said cylindrical expandable part, opposite to a tip edge of said cylindrical part,
inner diameters of said inlet part and said cylindrical expandable part are set greater than the
outer diameter of said hose inserted along the contracting diameter tapered surface of said bulging
part when said hose is being inserted and are set smaller than the outer diameter of said hose
inserted along the contracting diameter tapered surface of said bulging part when said pressure

surface part is pressing said expandable sleeve with said chuck tightener moving further in an axial
direction, and
an axial distance between said stopper and said annular flange is set same as between the tip
edge of said cylindrical part and said annular step part.
2. The hose joint according to Claim 1,
wherein an annular convex part is formed at an inlet part of said expandable sleeve, opposite to
the outer peripheral surface of said hose,
an inner diameter of the annular convex part is set greater than the outer diameter of said hose ■
inserted along the contracting diameter tapered surface of said bulging part when said hose is
being inserted and is set smaller than the outer diameter of said hose inserted along the
contracting diameter tapered surface of said bulging part when said pressure surface part is
pressing said expandable sleeve along with said chuck tightener moving further in an axial
direction.
3. The hose joint according to Claim 1 or 2,
wherein a pressure tube part is formed opposite to the expanding diameter tapered surface of
said bulging part on the inner peripheral surface of said chuck tightener along with the chuck
tightener moving further in an axial direction, as separated or integrated, and an engagement
concave part is formed opposite to an annular space formed between the hose insertion direction
side end surface of the pressure tube part and a counter-hose insertion direction side end surface
of the expandable sleeve in a state of the chuck tightener tightened by moving in an axial direction.
4. The hose joint according to Claim 1, 2 or 3,
wherein the annular flange opposite to the tip surface of said hose is formed toward the back side
outer peripheral surface of said nipple at the end part of said expandable sleeve in the hose
insertion direction.

ABSTRACT

The present invention provides a hose joint to improve a sealing performance and stability not to
slip out between an outer peripheral surface of a nipple and the hose by stabilizing at the place
where the hose tip is pushed into. When the hose H is inserted, an inner diameter of an inlet part
3a opposite to a contracting diameter tapered surface 1a2 of an expandable sleeve 3 is set greater
than an outer diameter of the hose H inserted along the contracting diameter tapered surface 1a2
of the bulging part 1a, and thereby the hose may be smoothly inserted between the expandable
sleeve 3 and the contracting diameter tapered surface 1a2 in a position without the tip part of the
hose H blocked by the inlet part 3a of the expandable sleeve 3. After that, when the hose is
pressed by a pressure surface part 2b along with the chuck tightener 2 moving in an axial direction,
the inner diameter of the inlet part 3a of the expandable sleeve 3 is set smaller than the outer
diameter of the hose H inserted along the contracting diameter tapered surface 1a2 of the bulging
part 1a, thereby the hose H is interposed between the inlet part 3a of the expandable sleeve 3 and
the contracting diameter tapered surface 1a2 of the nipple 1.