[0001] The present invention relates to an adapter for motorhomes, in particular to an adapter
for filling a tank of a motorhome with water.
[0002] Motorhomes are provided with a water tank which is periodically filled to guarantee
a satisfactory water supply.
[0003] The tank is normally filled with a common flexible tube, the end of which is inserted
into the inlet mouth of the tank.
[0004] Although the flexible tube usually has a smaller cross section than the inlet mouth
of the tank so that it can be inserted into the tank inlet, the users who load the
water usually hold the flexible tube in their hand to avoid spills.
[0005] The tank is normally very large to ensure a satisfactory water reserve for long distances
and so the filling time is normally long, even longer than ten minutes.
[0006] The user is often tempted to leave the end of the flexible tube inserted into the
inlet mouth while filling.
[0007] Disadvantageously, the overpressure in the hydraulic system can cause the end of
the flexible tube to slip out of the inlet mouth of the tank and cause unwelcome spills.
[0008] Furthermore, the opening tap of the water network is often far away from the inlet
mouth of the tank, or at least not close enough to allow it to be opened while holding
the flexible tube near the end of the flexible tube inserted into the inlet mouth
of the tank to prevent pulling out caused by the excessive water pressure.
[0009] The use of connectors, e.g., threaded connectors, is known to secure the flexible
tube to the inlet mouth of the tank; however, the inlet mouth of the tank must be
provided with a specific fitting associated with the end of the flexible tube, e.g.,
screw-nut screw connectors.
[0010] Disadvantageously, the situation may occur of having flexible tubes with different
cross sections which are not adapted to a specific fitting. Furthermore, the fitting
may not be compatible with the connector of the inlet mouth of the tank.
[0011] It is known to use adapters having a first threaded end which can be coupled to a
complementary threaded connection of the inlet mouth of the tank, and a second end
with protrusions to be able to withhold the end of the flexible tube able to fit onto
said second end of the adapter. For example, see the solution suggested in
US-4266813.
[0012] Disadvantageously, the diameter of the flexible tube must be complementary to the
second end of the adapter, and the problem remains of needing to provide a thread
in the first end complementary to the thread of the connector of the inlet mouth of
the tank.
[0013] FR-878805 shows a fitting for flexible tubes having different cross section, consisting of
two stepped ends with retaining projections. Each end may be fitted on flexible tubes
ends having different cross sections. Disadvantageously,
FR-878805 does not show how to associate a flexible tube with an inlet mouth of a tank, in
particular of a motorhome.
[0014] Securing a flexible tube to the inlet mouth of a tank by means of a threaded coupling
has the additional problem of removing the air present inside the empty tank, which
in fact hinders the complete filling and also causes dangerous backflow of water under
pressure.
[0015] US-7793688 shows an adapter for motorhomes having a first end threaded for connection to the
tank inlet mouth, and a second end having a quick coupling connector compatible with
a fitting associated with the end of the flexible tube. Said adapter is used to drain
water from the tank to prevent it from freezing during the winter.
[0016] Disadvantageously, the adapter requires complicated pressure relief and can only
be used when emptying the tank.
[0017] US-2007/0256755 describes a fluid transfer adapter, comprising a first threaded coupling portion
able to couple with an inlet mouth of a container, and a second coupling portion able
to couple with an end of a flexible tube.
[0018] It is object of the present invention to make an adapter for filling the tanks of
motorhomes which allows the use of flexible tubes of different size.
[0019] It is a further object of the present invention that said adapter allows coupling
with an inlet mouth of the tank of the motorhome without spills of liquid.
[0020] It is a yet further object of the present invention that the coupling, with the flexible
tube and the inlet mouth of the tank, is safe and allows the users to release their
grip on the flexible tube during filling.
[0021] According to the invention, said and further objects are achieved by an adapter for
filling a tank of a motorhome with a liquid under pressure, comprising a first coupling
portion able to couple with an inlet mouth of the tank, a second coupling portion
able to couple with one end of a flexible tube, and a through hole which passes through
the adapter from a first end to a second end of the adapter, wherein the first coupling
portion develops starting from the first end and the second coupling portion develops
starting from the second end,
characterized in that
the first coupling portion is tapered towards the first end to allow the coupling
with inlet mouths of tanks with different cross section, and provides an external
surface with pressure relief grooves.
[0022] Advantageously, it is possible to fill a tank in complete safety, without pressure
backflows and unwelcome water leaks or even breakage of the adapter.
[0023] The user works safely by firstly securing the flexible tube to the adapter and then
the adapter to the inlet mouth of the tank: only when the connection is established,
he opens the water tap.
[0024] The adapter is also flexible in use, responding to different sizes of the flexible
tube and of the inlet mouth of the tank.
[0025] These and other features of the present invention will become further apparent from
the following detailed description of practical embodiments thereof illustrated by
way of non-limiting example in the accompanying drawings, in which:
figure 1 shows a perspective view of an adapter according to a first embodiment of
the invention;
figure 2 shows a perspective view of an adapter according to a second embodiment of
the invention;
figure 3 shows a top plan view of the adapter in figure 1;
figure 4 shows a top plan view of the adapter in figure 2;
figure 5 shows a section view taken along line V-V of figure 3;
figure 6 shows a section view taken along line VI-VI of figure 4.
[0026] An adapter 1 for motorhomes has an elongated shape and comprises two coupling portions
2, 3, a first coupling portion 2 able to couple with an inlet mouth of a tank of a
motorhome, and a second coupling portion 3 able to couple with an end of a flexible
tube.
[0027] The adapter 1 has a first end 21 and a second end.
[0028] The first coupling portion 2 develops starting from the first end 21, while the second
coupling portion 3 develops starting from the second end 31.
[0029] The two coupling portions 2, 3 thus develop towards each other to make maximum use
of the length of the adapter 1, which has a through hole 4 passing through it from
one end 21, 31 to the other end 31, 21.
[0030] The first portion of the coupling 2 provides pressure relief grooves 5 on the external
surface 6, preferably three angularly equidistant pressure relief grooves 5 (see figures
3 and 4, in which two consecutive pressure relief grooves 5 are 120° apart).
[0031] The pressure relief grooves 5 develop longitudinally from the first end 21 towards
a middle zone 7 of the adapter 1.
[0032] The pressure relief grooves 5 are formed on the external surface 6 of the first coupling
portion 5, preferably by milling. Each pressure relief groove 5 thus has a concave
surface which develops longitudinally on the external surface 6 of the first coupling
portion 2, without entering the through hole 4.
[0033] The first coupling portion 2 is slightly tapered towards the first end 21, and the
pressure relief grooves 5 with it, to facilitate the coupling with the inlet mouths
of tanks of different size.
[0034] In a first embodiment (figures 1, 3, and 5), the second coupling portion 3 provides
a step external surface 8, wherein the steps are able to progressively reduce the
cross section of the second coupling portion 3 towards the second end 31.
[0035] In a second embodiment (figures 2, 4 and 6), the second coupling portion 3 provides
a quick coupling connector 9 at the second end 31. Preferably, an step external surface
10 of the same type as the step external surface 8 of the first embodiment of the
second coupling portion 3 is provided between the middle zone 7 and the quick coupling
connector 9.
[0036] A quick coupling connector 9 is a snap-on coupling type, e.g., of the type known
in gardening.
[0037] The through hole 4 preferably comprises a first constant cross section in the first
coupling portion 2, and a second constant cross section in the second coupling portion
3, wherein the first constant cross section is greater than the second constant cross
section. An oblique section of the through hole 4 is provided in the middle zone 7
to connect the two different sizes of the cross section of the through hole 4. The
larger cross section area of the through hole 4 at the first coupling portion 2 allows
a reduction in the pressure of the water entering the tank.
[0038] It is worth noting that the relief pressure grooves 5 do not change the first cross
section of the first coupling portion 2, which remains constant. The pressure relief
grooves 5 do not enter the through hole 4 but remain outside to avoid disturbing said
reduction of water pressure at the tank inlet.
[0039] Operationally, if the user has available a flexible tube with an end fitting able
to couple with the quick coupling connector 9, the adapter 1 will be used according
to the second embodiment (figures 2, 4 and 6).
[0040] The flexible tube is easily secured to the quick coupling connector 9 and the first
coupling portion 2 is inserted into the inlet mouth of the tank.
[0041] The outwardly tapered shape of the first coupling portion 2 allows an easy adaptation
to different cross sections of the inlet mouth.
[0042] For example, if a first tank has a first inlet mouth having a larger cross section
than a second inlet mouth of a second tank, the first coupling portion 2 will fit
deeper into the first inlet mouth of the first tank than it fits into the second inlet
mouth of the second tank.
[0043] As can be seen in figures 5 and 6, the tapering is continuous towards the first end
21. The variation of the insertion depth of the first coupling portion 2 is thus progressive
according to the cross section of the tank inlet.
[0044] Once the adapter 1 has preferably been blocked by interference with the outer surface
of the inlet mouth of the tank, the user can release the grip of the flexible tube
and safely open the water tap, the water beginning to flow under pressure into the
tank through the flexible tube and through the through hole 4 of the adapter 1.
[0045] Advantageously, the pressure relief grooves 5 allow the air in the tank to escape
as it fills: the incoming water occupies the volume of the tank, pushing the air out.
[0046] Once the tank is filled, the user can close the tap and easily uncouple the adapter
1 from the inlet mouth because the pressure relief grooves 5 result in a discontinuity
of the coupling surface between the adapter 1 and the inlet mouth of the tank. Otherwise,
the first portion of coupling 2 would tend to remain attached to the inlet mouth;
an effort would be needed to pull it out which would damage both adapter 1 and the
tank inlet mouth.
[0047] If the flexible tube has a free end, namely without a complementary fitting to the
quick coupling connector 9, it is necessary to insert the second coupling portion
3 into the flexible tube at the free end of the flexible tube.
[0048] If the adapter 1 in addition to the quick coupling connector 9 also has the step
external surface 10, the same adapter 1 may be used if the cross section of the flexible
tube permits. Two steps of the step external surface 10 are shown in figure 6.
[0049] If a smaller cross section size of the second coupling portion 3 is required, the
adapter 1 may be used according to the first embodiment, wherein the step external
surface 8 has many more steps than the step external surface 10.
[0050] The step external surface 10 of the adapter 1 according to the first embodiment can
be extended, but it is unlikely to achieve a sufficient reduction in the cross section
useful for coupling flexible tubes with very small cross sections.
[0051] Instead, the first portion of coupling 2 is identical for both embodiments.
[0052] Advantageously, it is possible to fill a tank in complete safety, without pressure
backflows and unwelcome water leaks or even breakage of the adapter.
[0053] The user works safely by firstly securing the flexible tube to the adapter 1 and
then the adapter 1 to the inlet mouth of the tank: only when the connection is established
does the user open the water tap.
[0054] The adapter 1 is also flexible in use, responding to different sizes of the flexible
tube and of the inlet mouth of the tank.
[0055] The adapter 1 can be used to transfer drinking water when it is made of food-grade
material, e.g., nylon delrin pom C.
[0056] Obviously, the adapter 1 can be used for any kind of liquid and for various applications
which involve the filling of a tank (not necessarily of a motorhome, e.g., also of
a caravan) using a flexible tube: for example the filling of a tank with fuel or fertilizer.
1. Adapter (1) for filling a tank of a motorhome with a liquid under pressure, comprising
a first coupling portion (2) able to couple with an inlet mouth of the tank, a second
coupling portion (3) able to couple with one end of a flexible tube, and a through
hole (4) which passes thought the adapter (1) from a first end (21) to a second end
(31) of the adapter (1), wherein the first coupling portion (2) develops starting
from the first end (21) and the second coupling portion (3) develops starting from
the second end (31),
characterized in that
the first coupling portion (2) is tapered towards the first end (21) to allow the
coupling with inlet mouths of tanks with different cross section, and provides an
external surface (6) with pressure relief grooves (5).
2. Adapter (1) according to claim 1, characterized in that the pressure relief grooves (5) develop longitudinally from the first end (21) towards
a middle zone (7) of the adapter (1).
3. Adapter (1) according to claim 1 or 2, characterized in that the second coupling portion (3) provides a step external surface (8), wherein steps
are able to progressively reduce the cross section of the second coupling portion
(3) towards the second end (31).
4. Adapter (1) according to any one of the preceding claims, characterized in that the second coupling portion (3) provides a quick coupling connector (9) at the second
end (31).
5. Adapter (1) according to claim 4, characterized in that the second coupling portion (3) provides a step external surface (10) between the
middle zone (7) of the adapter (1) and the quick coupling connector (9), wherein steps
are able to progressively reduce the cross section of the second coupling portion
(3) towards the quick coupling connector (9).
6. Adapter (1) according to any one of the preceding claims, characterized in that the through hole (4) provides a first constant cross section in the first coupling
portion (2), and a second constant cross section in the second coupling portion (3),
wherein the first constant cross section is greater than the second constant cross
section, and wherein in the middle zone (7) of the adapter (1) it is provided an oblique
part of the through hole (4) able to connect the two different sizes of the cross
sections of the through hole (4).
7. Adapter (1) according to any one of the preceding claims, characterized in that the first coupling portion (2) provides angularly equidistant pressure relief grooves
(5).
8. Adapter (1) according to claim 7, characterized in that it is provided with three pressure relief grooves (5).