Note: Descriptions are shown in the official language in which they were submitted.
1039696
BACKGROUND OF THR INVENTION
1. Field of the invention.
The present invention relates to a pump for inflating
an inflatable member, and more particularl~ to hand pumps.
2. Description of the prior art.
A various assortment of hand pumps have been proposed
for use in inflating an inflatable member, such as a tire. Par-
ticularly when utilized to inflate a tire, such pumps are normally
; provided with a hose having an attachment at its outer end which
is threaded onto a valve stem of the tire. Since tires have a
recommended pressure at which they should be used, it is desirable
to know the pressure in the tires as the pumping proceeds. Anyone
who has inflated a tire with a hand pump is aware of the diffi-
culty and inconvenience involved in obtaining the correct pressure
in the inflated tire. First, the tire is inflated to an estimated
pressure, after which the hose attachment is unthreaded from the
valve stem, and the pressure must then be checked with a separate
pressure gauge. If the pressure in the tire is insufficient,
the hose is reattached to the stem, and the tire is inflated an
additional amount, after which the hose is removed and the
pressure is again checked with the gauge. This procedure may
continue a number of times until the desired pressure is
attained, during which the hose may be attached and removed a
number of times to verify the pressure in the tire.
- 25 If the tire has been overinflated, a pin in the
valve stem must be depressed or removed to deflate the tire some-
what, after which the pressure in the tire is again checked. If
deflation of the tire is insufficient, an additional amount or
- air must be removed from the tire until the correct pressure is
obtained. Thus, both inflation and deflation of the tire is
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ded by a considerable amo~nt of inconvenience resulting from
multiple attachments and removals of the hose, due to the necessity
of removing the hose when the pressure is checked with a gauge and
when the tire is deflated.
In addition, if the tire must be inflated at a user's home or
"on the road" in an emergency situation, a pressure gauge may be un-
available~ In such a case, the tire must be inflated to an estimated
pressure which may be quite different from the recommended amount,
and damage may result to the tire during its subsequent use.
A double-acting pump is disclosed in U.SO Patent No. 3,485,180
issued to wickenberg et al on December 23, 1969.
SUMMARY OF THE INVENTION
A principle feature of the present invention is the provision
of a pump which may be utilized to determine the amount of pressure
in a member being inflated by the pump.
The pump of the present invention includes an elongated hollow
. .
cylinder having a first closure adjacent one end of the cylinder and
a second closure adjacent the other end of the cylinder, with the
second closure having a bore extending therethrough. A piston is slid-
,
ably received for reciprocation in the cylinder, with the piston sep-
;~ arating the inside of the cylinder into a first chambar intermediate
; the piston and the first closure and a second chamber intermediate the
.. . .
piston and the second closure. The pump includes a hollow piston rod
having one end connected to the piston and the other end extending out
i of the cylinder, with the rod being slidably received in the bore of
~ the second closureO Means is provided for connecting the other end of
- ~ the piston rod to an inflatable member. The pump has first one-way
valve means adjacent the first closure for permitting passage of air -
from outside the cylinder into the first chamber, while preventing
passage of air out of the first cham~er. The pump ~so has
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1~39696
second one-way valve means adjacent the second closure for permitting
passage of air from outside the cylinder into the second chamber, while
preventing passage of air out of the second chamber. Valve means is
carried by the piston for establishing communication between either of
the chambers and the piston rod when the pressure in either of the cham-
bers exceeds pressure in the inflatable member and rod, in order that
air is pumped into the inflatable member when the piston is reciprocated
in the cylinder. The pump has opening means communicating between one
of the chambers and the piston rod adjacent its one end for permitting
relatively slow passage of air between the rod and the one chamber.
Thus, a feature of the present invention is that the location
assumed by the cylinder relative the piston after urging of the pis-
ton toward the end of the one chamber and after release of the cylinder
indicates the amount of pressure in the inflatable member.
A further feature of the invention is that the pressure may
be determined by the pump without removal of the connecting means from
~he inflatable member.
In a preferred embodiment of the invention, the cylinder
includes a transparent wall defining a longitudinal portion thereof.
The cylinder may include pressure indicia spaced longitudinally along
the wall.
Another feature of the invention is that the piston may be
,-. .
~ viewed through the transparent wall to determine the location of the
4 piston.
; 25 Still another feature of the invention is that the indicia
may be utilized to determine the pressure of the inflatable member as
indicated by the location of the piston viewed through the wall.
In a preferred embodiment of the invention, the piston rod
includes an outer thread adjacent its one end, and the piston includes
an annular flange having an internal thread for securement of the
piston to the rod. ~03~696
Yet another feature of the invention is that the opening
means comprises a tortuous groove between the threads of the piston
and rod.
The connecting means may comprise a hose having one end for
attachment to the inflatable member and the other end received in the
piston rod. The hose is movable between a first position with a sub-
stantial portion of the hose withdrawn from the piston rod, and a
second position with the hose substantially retracted into the piston
rod. The piston rod defines a passageway extending from the
` piston to the outside of the pump, and a frustro-conical seat is
located in the passageway. The hose includes a frustro-conical
.! enlarged portion adjacent its other end.
A feature of the invention is that the hose may be with-
j 15 drawn from the piston rod to its first position for inflation of the
inflatable member.
: ~ .
- Another feature of the invention is that the eniarged portion
~ of the hose engages against and seals with the seat when the hose is
¦ moved to its first position to prevent escape of air from the passage-~¦ 20 way during pumping.
; A further feature is that the enlarged portion of the hose, may be disenga'ged from the seat to deflate the inflatable member with-
out removal of the hose from the inflatable member.
Yet another feature of the invention is that the hose may be
moved to its second position with the hose substantially retracted into
the piston rod for storage of the hose and pump.
Furt~er features will become more fully apparent in the follo~-
ing description of the embodiments of this invention and from the
appended claims.
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1~39696
` DESCRIPTION OF THE DRAWINGS
In the drawings:
Fig. 1 is a fragmentary elevational view of one embodiment
of the pump of the present invention'
Fig. 2 is a fragmentary sectional view of the pump of Fig. 1,
showing a hose retracted into the pump for storage;
Fig. 3 is a fragmentary view, taken partly in section, of a
handle portion of the pump of Fig. 1, showing the hose substantially
withdrawn from the pump for use in inflating an inflatable member;
Fig. 4 is a fragmentary view, taken partly in section, of the
pump of Fig. 3, showing the hose slightly retracted into the pump for
deflation of the inflatable member;
~, Fig. 5 is a fragmentary sectional view on an enlarged scale
showing one end of a cylinder in the pump of Fig. l;
1 15 Fig. 6 is a fragmentary view on an enlarged scale and taken
i partly in section, showing a piston in the pump of Fig. l;
Fig. 7 is a fragmentary sectional view on an enlarged scale,
showing opening means in the pump of Fig. 6;
Fig. 8 is a fragmentary view on an enlarged scale and taken
2~ partly in section, showing the other end of the cylinder of the pump
of Fig. l; ' -
Fig. 9 is a fragmentary view, taken partly in section, show-
ing another embodiment of the pump of the present'invention; and
Fig. 10 is a fragmentary elevational view of the pump of
Fig. 9.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
- Although the pumps of the present in~ention may be utilized
to inflate any appropriate inflatable member, as desired, the pumps as
described are partlcularly adapted for inflating a vehicle tire. In
particular, the pump disclosed in connection with Figs. 1-8 is particu-
__ _
1~39696
` larly useful for inflating the tires of a smaller vehicle, such as a
bicycle. As will be seen below, the pump described in connection with
Figs. 9 and 10 is very useful for inflating the tires of a larger
vehicle, such as an automobile. However, as noted above, it will be
understood that the pumps may be utilized for inflating any inflatable
member by providing a suitable attachment for the pump to the inflat-
able member.
Referring now to Figs. 1 and 2, there is shown a pump gener-
~lly designated 20 having an elongated hollow cylinder 22 and a handle
24 to facilitate manipulation of the pump. The cylinder 22 has a
first closure 26 adjacent one end 28 of the cylinder, and a second
closure 30 adjacent the other end 32 of the cylinder 22, with the
second closure 30 having a bore 34 extending therethrough.
In a preferred embodiment, the outer wall 36 of the cylinder
22 includes a longitudinally extending transparent wall portion 38, such
as a clear plastic, for viewing of the inside of the cylinder. For
convenience, the entire outer wall 36 of the cylinder 22 may be made of
a transparent material to provide the transparent wall portion 38. The
transparent wall portion 38 may include a plurality of pressure deter-
mining indicia 40 which are spaced longitudinally along the wall por-
tion 38 for a purpose which will be described below.
The pump 20 includes a piston 42 which is slidably received
inside the cylinder 22 for reciprocation therein. The piston divides
the inside of the cylinder 22 into a fixst chamber 44 intermediate the
piston 42 and the first closure 26 and a second chamber 46 intermedi-
ate the piston 42 and the second closure 30. An elongated hollow pis-
ton rod 48 has one end 50 connected to the piston 42, and the other end
- 52 extending out of the cylinder 22, with the rod 48 being slid2bly
~ received in the bore 34 of the second closure 30O The handle 24 has an
; 30 annular flange 54 which is secured to the other end 52 of the piston rod
48, and which defines an extension of a passageway 56 in the piston rod
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1~39696
48 to the outside of the pump 20. The pump 20 also includes a hose 58
made of flexible material, such as rubber, having an attachment
member 59 adjacent one end 60 for attachment of the hose to the
valve stem of a tire tnot shown), and the other end 62 received in the
$ passageway 56 of the piston rod 48. The hose 58 serves as means for
connecting the piston rod 48 to the inflatable member or tire, as will
be seen below.
As best shown in Figs. 2 and 5, the first closure 26 may com-
prise an annular plug 64, having a threaded portion 66 which is engage-
able with an internal threaded portion 68 of the cylinder 22 for secure-
ment of the plug 64 onto the one end 28 of the cylinder 22. The plug
64 or first closure 26 has aperture means 70, such as a plurality of
apertures, as shown, communicating between the inside and the outside of
the cylinder 22. An annular flexible valve member 72 is secured to the
. inner end of the plug 64 by an annular flange 74 on the plug 64, which
is received in a corresponding annular groove 76 in the valve member 72.
The valve member 72 has an annular flexible lip 78 which is directed
toward the first chamber 44 and which engages against the inside of the
~: cylinder 22 to prevent passage of air from the first chamber 44 to the
aperture means 70 and outside of the pump 20. However, the annular lip
78 flexes away from the inside of the cylinder 22 to permit passage or
air from the aperture means 70 into the first chamber 44 when the pres-
sure in the first chamber 44 is less than atmospheric pressure outside
of the pump 20. Thus, the valve member 72 serves as a first one-way
: 25 valve means for permitting passage of air .from outside the cylinder
22 into the first chamber 44, while preventing passage of air out of
~ the first chamber 44. The plug 64 also has a recess 89 at its outer
- end for a purpose which will be described below.
Referring nGW to Figs. 2 and 8, the second closure 30 may com-
prise an annular plug 80 having a threaded portion 82 which is èngagea~le
. 7
. _ .. ... . .
` 1~39696
with an internal threaded portion 84 of the cylinder 22 for securementof the plug 80 to the other end 32 of the cylinder 22. The plug 80 or
Second closure 30 has aperture means 86, such as a plurality of aper-
tures, as shown, communicating between the inside and the outside of
the cylinder. An annular flexible valve member 88 is secured to the
- inner end of the plug 80 by an annular flange 90 on the plug 80 which
is received in a corresponding annular groove 92 in the valve member
88. The valve member 88 has a first annular flexible lip 94 which is
directed toward the second chamber 46 and which engages against the
inside of the cylinder 22 to prevent passage of air from the second
chamber 46 to the aperture means 86 and out of the pump 20. The first
lip 94 flexes away from the inside of the cylinder 22 to permit pass-
age of air from the aperture means 85 to the second chamber 46 when
the pressure in the second chamber 46 is less than atmospheric pres-
sure outside of the pump. Thus, the valve member 88 serves as asecond one-way valve means for permitting passage of air from outside
the cylinder into the second chamber 46, while preventing passage
o~ air out of the second chamber.
- As previously noted, the piston rod 48 is slidably received
in a bore 34 extending through the second closure 30 or plug 80. The
: valve member 88 includes a second annular lip 96 which is directed
.-. . . .
toward the second chamber 46 and which prevents passage of air out~ of
the second chamber 46 through the bore 34 between the plug 80 and the
piston rod 48. As shown, the lips 94 and 96 define an annular recess
98 facing toward the second chamber 46, the purpose of which will be
described below.
; As best illustrated in Figs. 2 and 6-8, the piston 42
includes an annular flange 100 having an internal threaded portion 102.
The one end 50 of the piston rod 48 has an outer threaded portion 104
engageable with the threaded portion 102 of the flange 100 for secure-
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1039696
ment of the piston rod 48 to the piston 42. As best shown in Fig. 7,
I the threaded portions 102 or 104 of either the flange 100 or piston
c rod 48 may have rounded or cut-off ends in order to define a tortuous
passageway 106 between the threaded portions 102 and 104. In Fig. 7
the threaded portion 104 of the piston rod 48 is shown as having cut-
off ends 108 to define the passageway 106, although it is understood
that the threaded portion 102 of the flange 100 could have cut-off
ends to produce the same results. The passageway 106 between the
threaded portions 102 and 104 spirals around the piston rod 48, and
communicates between the second chamber 46 and the inside of the pis-
ton rod 48. Thus, the passageway 106 permits a relatively slow pass-
age of air between the piston rod 48 and the second chamber 46 due to
the relatively small dimensions of the passageway 106 and the tortuous
path defined by the passageway. The purpose for which the passageway
lS utilized will be described in detail below.
The piston 42 has an annular groove 110 and a plurality of
-~ passageways 112 communicating between the inside of the piston rod 48and the inner end of the groove 110. The piston 42 carries an annular,
flexible, V-shaped valve member 114 received in the groove 110. The
valve member 114 has a pair of inner diverging lips 116a and 116b
which converge toward an outer sealing ring 118. The lips 116a and b
releasably engage against and seal with the side walls of the groove
110, and thus cover the passageways 112. The ring 118 engages against
and seals with the inside of the cylinder 22 to prevent passage of air
between the first and second chambers 44 and 46.
Once th~ hose 58 is connected to the tire, if the pressure- in
the first chamber 44 exceeds the pressure inside the piston rod 48 and
the connected tire, the lip 116b of the valve member 114 flexes away
;~ from the side wall of the groove 110 to permit passage of air from thefirst chamber 44 through the piston rod 48 to the tire. However, when
:`
.: .
` 1~39696
the pressure inside the tire and piston rod 48 exceeds the pressure in
the first chamber 44, the lip 116b seals against the side wall of the
groove 110 and prevents passage of air from the tire back into the
first chamber 44. Similarly, when the pressure in the second chamber
46 exceeds the pressure inside the piston rod 48 and the connected tire,
the lip 116a of the valve member 114 flexes away from the side wall of
the groove 110 to permit passage of air from the second chamber 46
through the piston rod 48 to the tire. If the pressure in the tire and
the piston rod 48 exceeds the pressure in the second chamber 46, the
lip 116a seals against the side wall of the groove 110 to prevent pass-
age of air from the tire and piston rod 48 to the second _hamber 46.
Thus, the valve member 114 serves as valve means carried by the piston
for establishing communication between either of the chambers 44 or 46
and the piston rod 48 when the pressure in either of the chambers
exceeds the pressure in the piston rod and tire. The use of the pis-
ton 42 and valve member 114 for pumping air into the tire will be des-
.
cri~ed in detail below.
The flange 100 of the piston 42 preferably includes an annu-
lar extension 120 which is spaced from the piston rod 48 and which is
I 20 directed toward the second closure 30. As best shown in Fig. 8, when
i the piston 42 nears the valve member 88 associated with the second clo-
sure 30, the extension 120 is received in the recess 98 between the
lips 9i and 96 of the valve member 88. The extension 120 abuts against
: the connecting portion of the valve member 88 between the lips 94 and
96 to prevent damage to the lips by the piston.
The operation of the hose 58 is best described in connection
with Figs. 2-4. The annular flange 54 of the handle 24 has a frustro-
. .
conical valve seat 122 adjacent the other end 52 of the piston rod 48.
The hose 58 has an enlarged portion 124 of frustro-conical shape adja-
cent its other end 62. The shape of the enlarged portion 124 may be
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~039696
defined by a rigid insert 126 of frustro-conical shape which is received
in the other end 62 of the hose 58, as shown in Fig. 2.
The hose 58 is movable between a first positi,on with a sub-
stantial portion of the hose withdrawn from the piston rod, as shown in
Fig. 3, and a second position with a substantial portion of the hose
retracted into the piston rod, as shown in Fig. 2. When the hose 58 is
moved to its first position, as shown in Fig. 3, the enlarged portion
124 sealingly engages against the seat 122 to prevent the escape of air
from the passageway 56 of the piston rod 48. Thus, the hose 58 is located
in its first position when it is desired to inflate the tire.
As best illustrated in Fig. 4, the outside diameter of the
hose 58 adjacent the enlarged portion 124 is slightly less than the
inside diameter of the seat 122, and the outside diameter of the enlarged
portion 124 is less than the inside diameter of the passageway 56. Thus,
when it is desired to deflate the inflated tire, the enlarged portion
124 of the hose 58 is disengaged slightly from the seat 122 to permit
passage of air from the hose to the outside of the pump through the
- space between the seat 122 and the hose, as indicated by the direction
of the arrows in Fig. 4. The release of air from the tire is thus
; 20 accomplished without removal of the attachment member 59 from the valve
- stem of the tire. When the tire has been deflated a desired amount, the
- enlarged portion 124 is again sealingly engaged against the seat 122 to
prevent the further escape of air from the tire, as shown in Fig. 3.
When it is desired to store the pump, the attachment mem~er 59 of the
hose 58 is removed from the valve stem of the tire, and the hose is
moved to its second position retracted into the pump, as illustrated in
.; . .
- Fig. 2.
-~ The use of the pump for inflating a tire is described as fol-
lows. The hose 58 is first moved from its second storage position to
- 30 its first operating position, as shown in Fig. 3, until the enlarged
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1~39696
portion 124 of the hose engages against and seals with the seat 122.
The attachment member 59 of the hose 58 is then threaded onto the valve
stem of the tire. Next, the handle 24 and cylinder 22 are grasped and
pumped by the user's hands to reciprocate the piston 42 in the cylinder
22.
As the piston 42 moves toward the first closure 26 a vacuum
is created in the second chamber 46. Accordingly, air passes from the
outside of the pump through the aperture means 86 of the second closure
30 and past the lip 94 of the valve member 88 into the second chamber
46.- If the pressure in the tire is greater than atmospheric pressure,
the valve member 114 will prevent passage of air between the tire and
second chamber. In addition, air is compressed in the first chamber 44
as long as the pressure in the tire is greater than the pressure in the
first chamber, since the valve member 72 prevents passage of air from
the first chamber 44 out of the pump and the valve member 114 prevents
- passage of air from the first chamber to the tire. When the pressure
in the first chamber 44 exceeds the pressure in the tire and the inside
of the piston rod 4&, the lip 116b of the valve member 114 flexes away
from the side wall of the groove 110 in the piston to permit passage of
; 20 air from the first chamber 44 through the piston rod 48 and into the tire.
The lip 116a of the valve member 114 remains sealed against the sidewall
of the groove 110, since the pressure in the first chamber 44 and piston
rod 48 exceeds the pressure in the second chamber 46. This condition
continues until the piston 42 nears the first closure 26, such that air
is continuously pumped from the first chamber 44 into the tire.
. When the piston 42 is moved toward the second closure 30 a
` vacuum is created in the first chamber 44. Accordingly, air is per-
'.':
mitted to pass from the outside of the pump into the first chamb~r 44
around the lip 78 of the valve member 72, while air is prevented from
passing between the tire and first chamber 44 by the valve ~ember 114.
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1~39696 -
As long as the pressure ih the tire is greater than the pressure in the
second chamber, air will be compressed in the second chamber because
the valve members 88 a~nd 114 prevent passage of air out of the second
chamber. Bowever, when the pressure in the second chamber exceeds
the pressure in the tire as the air is compressed, the lip 116a of the
valve member 114 flexes away from the sidewall of the groove 110, and
air passes from the second chamber 46 through the piston rod 48 into
the tire. The lip 116b of the valve member 114 remains sealed against
the sidewall of the groove llO to prevent passage of air from the pis-
ton rod into the first chamber 44. This condition continues until thepiston 42 nears the second closure 30, such that air is continuously
pumped from the second chamber 46 into the tire.
Thus, the pump 20 of the present invention pumps air into the
tire as the piston 42 is reciprocated relative the cylinder 22 in both
directions, and the pump inflates the tire irrespective of which direc-
tion pumping takes place.
. .
i When it is desired to determine the pressure in the tire, the
piston 42 is moved to a position adjacent the valve member 88, as shown
in Fig. 8. Since air has passed from outside the pump into the first
chamber 44 during movement of the piston toward the valve member 88,
the pressure in the first chamber 44 is nearly atmospheric, and the
first chamber in this configuration of the pump has a fixed volume. If
the pressure in the tire is greater than atmospheric, the piston 42
will move toward the first closure 26 when the cylinder 22 is released
by the user. This follows since air is permitted to pass from the tire
- to the second chamber through the passageway 106, and the pressure in
the second chamber 46 is greater than the pressure in the first chamber
44. It is apparent that air will be compressed in the first chamber 44
during movement of the piston toward the first closure 26, since the
valve members 72 and 114 prevent passage of air out of the first c~ambe~.
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1~)39696
Movement of the piston toward the first closure continues until the
following condition of equilibrium is satisfied:
PlAl = P2A2,
where, Pl = the pressure of the compressed air in the first
chamber,
Al = the area of a cross-section through the first chamber,
P2 = the pressure in the second chamber and tire, and
A2 = the area of a cross-section through the second
chamber, less the area of a cross-section
through the wall of the piston rod.
The variable distance which the piston travels from the second closure
toward the first closure will, of course, be determined by the pressure
- in the tire, since the first chamber has a fixed volume and pressure
when the piston is located adjacent the second closure, as noted above.
Accordingly, the location assumed by the cylinder 22 relative
the piston 42 is indicative of the amount of pressure in the tire.
Since the piston 42 is visible through the transparent wall portion 38
. . .
of the cylinder 22, as shown in Fig. 1, the piston 42 or part thereof
~ may be used as a pointer in conjunction with pre-calibrated indicia 40
-~ 20 on the cylinder to determine the pressure in the tire. If desired, the
indicia 40 may be calibrated to use the valve member 114 of the piston
. 42 as an indicator to determine the amount of pressure in the tire.
; In the example shown in Fig. 1, the valve member 114 of the piston 42
.
; indicates that a pressure value of 60 is present in the tire.
.,.~
It is noted at this point that passage of air between the
~ - .
second chamber 46 and the piston rod 48 through the passageway 106 is
sufficiently slow to prevent impairment of the normal pumping operation,
while sufficient passage of air through the passageway 1~6 is permitted
to obtain a relatively quick reading of the tire pressure. Although
the passageway 106 has been shown as communicating between the second
chamber 46 and the piston rod 48, it is apparent that the passageway
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1~39696
could be connected between the first chamber and the piston rod with
equally beneficial results. In such a case, the piston 42 would be
moved toward the first closure 26 prior to release of the cylinder to
obtain a pressure reading, and the indicia 40 must be calibrated
accordingly.
Thus, a pump according to the present invention has been
described which inflates the inflatable member or tire irrespective of
which direction the cylinder 22 is moved relative the piston 42. Also,
the pump of the present invention may be utilized to determine the
pressure in the tire, as described above, in order to determine whether
the pumping operation should continue. If the tire has been inadver-
tently overinflated, the enlarged portion 124 of the hose 58 may be
- slightly disengaged from the valve seat 122 to de1ate the tire a
desired amount.
As dis~ussed above, the pump disclosed in connection with
Pigs. 1-8 is particularly adapted for inflating a relatively small tire,
such as a bicycle tire. Accordingly, the pump is also constructed for
convenient storage of the pump between a pair of spaced fixtures (not
shown) on a bicycle. For storage, the hose 5g is moved to its retracted
position in the piston rod 48, and the cylinder 22 is moved toward the
handle 24, as best shown in Fig. 2. The pump 20 has a helical spring
128 extending from the annular flange 54 of the handle 24 toward the
second closure 30, with the spring 128 extendinq around a longitudinal
portion of the piston rod 48. As the cylinder 22 is moved toward the
handle 24, the spring is compressed between the handle 24 and the sec-
ond closure 30. The pump 20 ma~ be positioned between the spaced fix-
. . .
tures on the bicycle with the spring 128 compressed, and the cylinder
22 may be released by the user to permit the spring 128 to move the
cylinder 22 away fro~ the handle 24, such that one fixture is received
in the recess 89 of the first closure 26 and the other fixture is
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11~)39696
received in the attachment member 59 of the hose 58. Accordingly,
the pump is retained between the fixtures on the bicycle for future
use.
Another embodiment of the invention, which is particular-
S ly adapted for inflating an automobile tire or the like, is illustrated
in Figs. 9 and 10. The pump of Figs. 9 and 10 is similar in structure
and operation to the pump described in connection with Figs. 18, and
like reference numerals will be utilized in Figs. 9 and 10 to designate
like parts.
The pump 20 of Figs. 9 and 10 has a handle 130 secured
to the first closure 26 by any suitable means, such as a threaded
bolt 132 depending from the handle 130 which is threaded into an intern-
ally threaded projection 134 extending from the first closure 26,
as shown in Fig. 9. In this embodiment, the other end 52 of the piston
rod 48 is threadedj and a foot member 136 having a pair of lower opposed
flanges 138a and 138b is secured to the other end 52 of the piston
rod 48 by a pair of threaded bolts 140a and 140b, as shown. In this
.. ~ .
~ embodiment of the invention, the other end 62 of the hose 58 is secured
. . .
directly to the other end 52 of the piston rod 48 by an annular flange
142 which is pressed over the other end 62 of the hose to engage the
hose between the flange 142 and threads of the piston rod.
In use of the pump of Figs. 9 and lO, the user's feet
- are placed over the opposed flanges 138a and b of the foot member
136 to anchor the pump to the ground, while the piston 42 is reciprocat-
ed in the cylinder 22 by grasping and moving the handle 130. In other
respects, the operation of the pump is similar to that described in
connection with the pump of Fig. 18. In particular, air is pumped
from both chambers of the cylinder, and the pressure of the tire may
be determined by the pump, as described above.
The foregoing detailed description is given for clearness
of understanding only, and no unnecessary limitations should be understood
therefrom as modifications will he obvious to those skilled in the
art.
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