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Patent Abstract
To make it easy to mount magnets for monitoring a switched state
of a valve element in a solenoid valve and to easily mount magnetometric
sensors for sensing an approach of the magnet in a state of excellent
water resistance and dustproof property. In a solenoid valve for
switching a direction of a flow of pressure fluid by driving the
solenoid valve by pilot fluid pressure, ring-shaped magnets 13A
and 13B are fitted with small-diameter portions 11a formed at end
portions of a valve element 11 and is fixed by press fitting and
engaging caps 14A and 14B forming faces to be in contact with pistons
14A and 14B at the valve element ends. A housing chamber 30 is formed
outside a valve hole 10a in a valve body 10 and in a position close
to the magnets, magnetometric sensors 31A and 31B are housed in
the housing chamber 30, and a cover 35 is mounted to the housing
chamber 30. A connector 37 for leading out a current-carrying wire
to pilot valves 20A and 20B and signal lines from the magnetometric
sensors is provided to the cover.
Patent Claims
1. A solenoid valve with a magnetometric sensor, said solenoid valve
comprising: a valve body including a plurality of ports; a valve
hole provided in said valve body; a valve element fitted for sliding
in said valve hole; pistons disposed for sliding on axial opposite
sides of said valve element; at least one pilot valve for supplying
pilot fluid to said pistons to switch said valve element; caps fitted
with opposite ends of said valve element and forming contact faces
with which said pistons come in contact at end portions of said
valve element; a ring-shaped magnet fitted with at least one of
said end portions of said valve element and fixed to said position
by said cap; a housing chamber formed in said valve body to be close
to said valve hole and said magnet; at least one magnetometric sensor
disposed in said housing chamber; and a cover with which said housing
chamber is covered.
2. A solenoid valve according to claim 1, wherein said housing
chamber extends close to axial opposite end portions of said valve
hole.
3. A solenoid valve according to claim 2, wherein a connector is
mounted to said cover and said connector, said pilot valve, and
said magnetometric sensor are connected to each other by a lead
passing through said housing chamber.
4. A solenoid valve according to claim 2, wherein an indicating
light for indicating an operating state of said pilot valve is provided
in said housing chamber and an indicating window through which said
indicating light is seen is formed at said cover.
5. A solenoid valve according to claim 2, wherein said solenoid
valve is placed on a base having fluid flow paths communicating
with said respective ports.
6. A solenoid valve according to claim 5, wherein said base includes
a duct for wiring, a connector is mounted in said duct, and said
connector, said pilot valve, and said magnetometric sensor are connected
to each other by a lead passing through said housing chamber.
Patent Description
TECHNICAL FIELD TO WHICH THE INVENTION BELONGS
[0001] The present invention relates to a solenoid valve with magnetometric
sensors in which magnets and the magnetometric sensors for monitoring
a switched state of a valve element and taking out the switched
state as a signal.
PRIOR ART
[0002] Conventionally, various proposals to attach magnets and
magnetometric sensors for monitoring a switched state by a valve
element of a solenoid valve and taking out the switched state as
a signal to the solenoid valve are made. However, it cannot be said
that adequate consideration is given to facilitating mounting of
the magnets and the magnetometric sensors and mounting of the magnetometric
sensors in a state of excellent water resistance and dustproof property.
DISCLOSURE OF THE INVENTION
[0003] It is an object of the invention to provide at low cost
a solenoid valve with magnetometric sensors in which mounting of
magnets for monitoring a switched state of a valve element in the
solenoid valve and taking out the switched state as a signal is
made easy, the magnetometric sensors for sensing an approach of
the magnet can be easily mounted in a state of excellent water resistance
and dustproof property, and as a result, safety and reliability
are improved.
[0004] To achieve the above object, in a solenoid valve with a
magnetometric sensor according to the present invention, said solenoid
valve comprising: a valve body including a plurality of ports; a
valve hole provided in said valve body; a valve element fitted for
sliding in said valve hole; pistons disposed for sliding on axial
opposite sides of said valve element; at least one pilot valve for
supplying pilot fluid to said pistons to switch said valve element;
caps fitted with opposite ends of said valve element and forming
contact faces with which said pistons come in contact at end portions
of said valve element; a ring-shaped magnet fitted with at least
one of said end portions of said valve element and fixed to said
position by said cap; a housing chamber formed in said valve body
to be close to said valve hole and said magnet; at least one magnetometric
sensor disposed in said housing chamber; and a cover with which
said housing chamber is covered.
[0005] According to the present invention, said housing chamber
extends close to axial opposite end portions of said valve hole.
[0006] According to the present invention, a connector is mounted
to said cover, said pilot valve, and said magnetometric sensor are
connected to each other by a lead passing through said housing chamber.
[0007] An indicating light for indicating an operating state of
said pilot valve is provided in said housing chamber and an indicating
window through which said indicating light is seen is formed at
said cover.
[0008] A solenoid valve according to the present invention is placed
on a base having fluid flow paths communicating with said respective
ports.
[0009] In the case, said base includes a duct for wiring, and said
connector is mounted in said duct, said pilot valve, and said magnetometric
sensor are connected to each other by a lead passing through said
housing chamber.
[0010] The solenoid valve with the magnetometric sensor having
the above structure is a solenoid valve having the magnet and the
magnetometric sensor for monitoring a switched state of the valve
element of the solenoid valve and taking out the switched state
as a signal, in which the magnet is fitted over the small-diameter
portion at the end portion of the valve element and fixed by press
fitting and engaging the cap forming the face in contact with the
piston at the valve element end. Therefore, mounting of the magnet
is made easy. Moreover, the housing chamber is formed outside the
valve hole in the valve body and in a position close to the magnet,
the magnetometric sensor is housed in the housing chamber, and the
cover is mounted to the housing chamber. Therefore, the magnetometric
sensor can be mounted easily in a state of excellent water resistance
and dustproof property.
[0011] Furthermore, the connector for gathering and leading out
the current-carrying wire to the pilot valve and the signal line
from the magnetometric sensor is provided to the cover of the housing
chamber or the wiring duct provided to be adjacent to the base,
the indicating light for indicating the operating state of the pilot
valve is provided in the housing chamber, and the indicating light
can be visually recognized through the indicating window of the
cover of the housing chamber. Therefore, not only the simplified
structures for handling the various wires and providing the indicating
light but also reduced possibilities of improper wiring and assembly,
easy assembly, and excellent safety, reliability, and economy can
be achieved.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] FIG. 1 is a vertical sectional view of a first embodiment
of a solenoid valve with magnetometric sensors according to the
present invention.
[0013] FIG. 2 is an enlarged sectional view of an essential portion
of the embodiment in FIG. 1.
[0014] FIG. 3 is a vertical sectional view of a second embodiment
of the solenoid valve with the magnetometric sensors according to
the invention.
[0015] FIG. 4 is an enlarged sectional view of an essential portion
of the embodiment in FIG. 3.
DETAILED DESCRIPTION
[0016] FIGS. 1 and 2 show a first embodiment of a solenoid valve
with magnetometric sensors according to the present invention. The
solenoid valve with the magnetometric sensors includes a solenoid
valve 1 for switching a direction of a flow of pressure fluid (compressed
air) and a base 2 having flow paths for supplying and discharging
the pressure fluid to and from respective ports of the solenoid
valve 1 in brief.
[0017] In the solenoid valve 1, a supply port P, first and second
output ports A and B, and first and second discharge ports EA and
EB open into a valve hole lOa formed to pass through a valve body
10 and a spool valve element 11 for switching a flow path between
the ports is fitted for sliding in the valve hole 10a. The valve
element 11 moves to one side or the other side in an axial direction
to thereby switch between the first and second output ports A and
B to connect the supply port P to the first or second output port
A or B and as a result, the output port which does not communicate
with the supply port P is connected to the first or second discharge
port EA or EB as known as the solenoid valve.
[0018] Although the solenoid valve shown in the drawings is a two
position valve in which the valve body 11 has two switching positions
on the one end side and the other end side of the valve hole, it
is also possible to employ a tree position valve having a neutral
stop position for maintaining the respective ports in closed or
open states.
[0019] Ring-shaped magnets 13A and 13B are fitted over small-diameter
portions 11a formed at opposite end portions of the spool valve
element 11. The magnets 13A and 13B are for detecting a position
of the spool valve element 11 by using the magnetometric sensors
which will be described later. The magnet 13A on one end of the
valve element 11 is fixed to the valve element 11 by press fitting
and engaging a cap 14A with the valve element end, the cap 14A being
made of synthetic resin and forming a face to be in contact with
a piston 23A which will be described later. The magnet 13B on the
other end of the valve element 11 is fixed to the valve element
11 by press fitting and engaging a cap 14B through a ring 15 and
one of sealing members 16a for the discharge port EB, the cap 14B
being made of synthetic resin and forming a face to be in contact
with a piston 23B. These caps 14A and 14B perform a function of
absorbing a shock of collision of the pistons 23A and 23B. The valve
body 10 and the spool valve element 11 are made of non-magnetic
material (aluminum) as a matter of course.
[0020] The cap 14A is mounted to the valve element by forming a
recessed groove 17 at the small-diameter portion 11a of the end
portion of the valve element 11, press fitting the small-diameter
portion 11a into the cap 14A which is made of synthetic resin and
which can be deformed slightly, and engaging a lug portion 18 on
an inner peripheral face of the cap with the recessed groove 17
as shown in detail in FIG. 2. The cap 14B on the other end of the
valve element 11 is mounted similarly. A reference numeral 16b in
FIG. 2 designates one of sealing members for the discharge port
EA.
[0021] Adaptors 21A and 21B mounted with pilot valves 20A and 20B
are provided to be adjacent to opposite ends of the valve body 10,
piston chambers 22A and 22B concentric with the valve hole 10a of
the valve body 10 are formed on junction faces of the adaptors 21A
and 21B joined to the valve body 10, and the pistons 23A and 23B
for coming in contact with the caps 14A and 14B at the end portions
of the valve element 11 are housed in the piston chambers 22A and
22B.
[0022] The pilot valves 20A and 20B are for supplying and discharging
pilot fluid pressure to and from the piston chambers 22A and 22B
to thereby drive the spool valve element 11 through the pistons
23A and 23B to switch a direction of a flow of pressure fluid. In
other words, if a solenoid of the pilot valve 20A is energized,
the pilot fluid pressure in a pilot supply flow path is introduced
into the piston chamber 22A by switching of a pilot valve element
and acts on the piston 23A. The spool valve element 11 moves rightward
in the drawing to switch the flow path in the valve body 10. If
energization of the solenoid of the pilot valve 20A is cancelled
and a solenoid of the pilot valve 20B is energized, the pilot fluid
pressure in the piston chamber 22A is discharged, the pilot fluid
pressure in the pilot supply flow path is introduced into the piston
chamber 22B and acts on the piston 23B, and the spool valve element
11 moves leftward in the drawing to switch the flow path in the
valve body 10.
[0023] In a position outside the valve hole 10a in the valve body
10 and close to the magnets 13A and 13B, a housing chamber 30 for
housing the magnetometric sensors 31A and 31B and the like is formed.
In other words, a recessed portion extending close to axial opposite
end portions of the valve hole 10a is formed on a side opposite
to the ports over the valve hole 10a in the valve body 10 and the
housing chamber 30 is formed of the recessed portion. Lead-out holes
32A and 32B for current-carrying wires 33A and 33B to the pilot
valves 20A and 20B in the adaptors 21A and 21B face a side face
of the housing chamber 30.
[0024] The magnetometric sensors 31A and 31B corresponding to the
magnets 13A and 13B are housed in the housing chamber 30 so as to
detect the magnets when the valve element 11 reaches predetermined
positions. A cover 35 is mounted to the housing chamber 30 and a
connector 37 for gathering and leading the current-carrying wires
33A and 33B to the pilot valves 20A and 20B and signal lines 36A
and 36B from the magnetometric sensors 31A and 31B outside is provided
to the cover 35. Furthermore, indicating windows 38A and 38B are
provided to the cover 35 of the housing chamber 30 and indicating
lights 39A and 39B for indicating operating states of the pilot
valves 20A and 20B are provided inside the indicating windows 38A
and 38B in the housing chamber 30.
[0025] In the two-position valve shown in the drawings, by detection
of the magnets 13A and 13B by the magnetometric sensors 31A and
31B, movement of the valve element 11 to each end position of the
valve hole 10a is detected. It is also possible that one magnetometric
sensor and one magnet are provided. In a case of a different flow
path switching method of the solenoid valve when the solenoid valve
is a three-position valve, it is possible to set detection positions
according to the method. In this case, the required numbers of magnets
and magnetometric sensors are provided and the numbers of them to
be disposed are normally one or two.
[0026] In the drawings, reference numerals 41A and 41B designate
printed boards to which the indicating lights 39A and 39B are mounted
and reference numerals 42A and 42B designate electric elements mounted
to the boards 41A and 41B.
[0027] On the other hand, the base 2 is formed as a manifold corresponding
to the one solenoid valve 1 and used by providing a large number
of manifolds to be adjacent to each other. In a base main body 50,
a supply flow path 51, output flow paths 52A and 52B, and discharge
flow paths 53A and 53B corresponding to the respective ports P,
A, B, EA, and EB of the solenoid valve 1 are provided. In order
to connect the supply flow paths 51 and the discharge flow paths
53A and 53B in the adjacent bases 2, the flow path 51 and the discharge
flow paths 53A and 53B communicate with a supply through hole 54
and discharge through holes 55A and 55B provided to pass through
a connecting face between the bases 2. The output flow paths 52A
and 52B separately open in an end face of the base 2.
[0028] FIGS. 3 and 4 show a second embodiment of a solenoid valve
with magnetometric sensors according to the invention. Because substantial
structure and operations of the second embodiment are not different
from those of the first embodiment except points described below,
main portions substantially similar to those of the first embodiment
are provided with reference numerals similar to those of the first
embodiment to omit descriptions of the portions.
[0029] First, in the solenoid valve with the magnetometric sensors
of the second embodiment, ring-shaped magnets 13A and 13B are fitted
over small-diameter portions 61a at opposite ends of a spool valve
element 61. The magnets 13A and 13B are fixed to the valve element
61 by press fitting and engaging caps 64A and 64B made of synthetic
resin. In other words, as shown in detail in FIG. 4, lug portions
67 are formed at the small-diameter portions 61a at the end portions
of the valve element 61, and caps 64A and 64B which are made of
synthetic resin and which can be deformed slightly are press fitted
over the small diameter portions 61a, and the lug portions 67 are
engaged with inner peripheral faces of the caps 64A and 64B, thereby
mounting the caps 64A and 64B. This structure is similar to that
of the fist embodiment in that the caps can be fixed by only press
fitting the caps over the small-diameter portions of the valve element.
[0030] Furthermore, a wiring passage (not shown) extending from
a housing chamber 80 to one side portion of a base main body 90
is provided in such a position of the base main body 90 as not to
interfere with a valve hole 60a and respective ports P, A, B, EA,
and EB in a valve body 60. Through the wiring passage, current-carrying
wires 73A and 73B to pilot valves 20A and 20B and signal lines 76A
and 76B from magnetometric sensors 31A and 31B are gathered and
lead out.
[0031] On the other hand, a wiring duct 92 in which respective
wires of the solenoid valve 1 mounted onto the base main body are
housed is provided on one side of the base main body 90. The whole
wiring duct 92 or a part of the wiring duct 92 is formed integrally
with the base main body 90 or formed separately. A connector 77
for connecting the current-carrying wires 73A and 73B and the signal
lines 76A and 76B to the wiring duct 92 and for leading the wires
and lines outside through the duct 92 is provided.
[0032] Although a cover 85 mounted to the housing chamber 80 for
housing the magnetometric sensors 31A and 31B is not provided with
the connector 37 shown in the first embodiment because the connector
77 is provided to the wiring duct 92, the cover 85 is provided with
indicating windows 88A and 88B and indicating lights 89A and 89B
are provided inside the indicating windows 88A and 88B.
[0033] The solenoid valve with the magnetometric sensors of the
first and second embodiments having the above structure is a solenoid
valve having the magnets 13A and 13B and the magnetometric sensors
31A and 31B for monitoring a switched state of the valve element
11, 61 of the solenoid valve 1 and taking out the switched state
as a signal, in which the magnets 13A and 13B are fitted over the
small-diameter portions 11a, 61a at the end portions of the valve
element and fixed by press fitting and engaging the caps 14A and
14B, 64A and 64B forming faces in contact with the pistons at the
valve element ends. Therefore, mounting of the magnets is made easy.
Moreover, the housing chamber 30, 80 is formed outside the valve
hole in the valve body 10, 60 and in a position close to the magnets,
the magnetometric sensors are housed in the housing chamber, and
the cover 35, 85 is mounted to the housing chamber. Therefore, the
magnetometric sensors can be mounted easily in a state of excellent
water resistance and dustproof property.
[0034] Furthermore, the connector 37, 77 for gathering and leading
out the current-carrying wires to the pilot valves and the signal
lines from the magnetometric sensors is provided to the cover 35
of the housing chamber or the wiring duct 92 provided to be adjacent
to the base, the indicating lights 39A and 39B, 89A and 89B for
indicating the operating states of the pilot valves are provided
in the housing chamber, and the indicating lights can be visually
recognized through the indicating windows of the cover of the housing
chamber. Therefore, not only the simplified structures for handling
the various wires and providing the indicating lights but also reduced
possibilities of improper wiring and assembly, easy assembly, and
excellent safety, reliability, and economy can be achieved.
[0035] According to the invention described above in detail, mounting
of the magnets for monitoring the switched state of the valve element
in the solenoid valve and taking out the switched state as the signal
is made easy and the magnetometric sensors for sensing an approach
of the magnet can be easily mounted in the state of excellent water
resistance and dustproof property. As a result, it is possible to
provide the solenoid valve with the magnetometric sensors having
improved safety and reliability at low cost.
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