Field of invention:
The present invention relates generally to the hydraulic filtration system, and more
particularly to an improved suction strainer fitted with magnets to capture the ferrous
dirt contamination in construction industry vehicles as well as other industrial
applications.
Object of invention:
The present invention describes a system of installation of magnetic rings in the
strainer for an improved and better filtration of the ferrous particles from the oil inside
the hydraulic tank. The magnetic rings and washers provided in the improved system
are aligned and placed alternately to each other in series. The internal diameter of
magnet rings is more than that of washer. By doing so, a pocket is formed which
captures the ferrous particles and contain the particles within the cavity. The
contamination can be removed on servicing. This will also keep the flow in a laminar
region.
Background:
It is a common problem that in machines related to construction equipment, the oil
inside the hydraulic tank can be contaminated by various types of ferrous particles.
These ferrous particles are the debris, resultant of the burrs, welds and many such
external factors. Since these ferrous particles are of very small size, ranging even
into microns, they remain uncaptured in the previous stage of filtering by coarsemesh
media. The specific components which get severely affected and whose
performance can deteriorate are pumps, valves, hydraulic cylinder etc.
Hence the filtration, capturing and consequent elimination of such fine particles
becomes very important and essential for smooth working of the hydraulic system.
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The object of present invention is to develop an improved suction strainer fitted with
magnets to capture the ferrous dirt contamination in construction industry. To
achieve the above objective it is proposed to trap such particles by providing
magnetic field in the strainer. The ring magnets are provided to keep the ring
geometry minimum.
There are already known filtration systems available in the art but they are neither
efficient in nature nor cost effective.
In one such known system in a known Magnetic suction filtration system, magnetic
rings are assembled with a rod and placed inside the shell. This arrangement
restricts the flow and filter size become big to maintain the laminar flow.
In another known system, magnetic rings are externally assembled on the filtration
media. In such systems, ferrous particle accumulates on the magnet ring in the form
of a chain. This chain can break due to shocks and initial start-up of hydraulic pump.
In this case, the magnetic rings reduce the filtration area of strainer, hence size
becomes large.
In another known system, magnet rings are mounted on hollow rod. In such systems,
particle chain is formed. This particle chain when gets broken due to shock or some
other way and causes severe deterioration to the hydraulic components. In this type
of system there is no provision of pockets where particle chain can be trapped. Also,
servicing for such systems is cumbersome. They are replaced while servicing and
brings the cost impact, thereby affecting the flow characteristics and hampering the
efficiency.
The above defects of the known systems are obviated by the proposed improved
system of the present invention. The proposed system is not only more efficient but
also is easier to handle, cost effective and can be reused.
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Object of the invention:
The prime object of the invention is elimination of the ferrous particle by providing
pocket formed by magnetic ring and non-magnetic washer. The ferrous particles that
are not filtered by the strainer mesh are locally captured in the pocket. The internal
diameter of ring magnet is more than that of washer. The magnetic rings and
washers are co-axially assembled in the shell body. It not only attracts or captures
the ferrous particles but also retains it. During the service of strainer, the whole
assembly can be disassembled to remove the collected particles,'The assembly can
be re-used.
Summary of the invention:
According to the present invention there is provided an improved suction strainer
fitted with magnets to capture the ferrous dirt contamination in construction
industry by providing a pocket formed by magnetic ring and non-magnetic washer,
the said filtration system being provided with the internal diameter of ring magnet
being more than that of washer and the magnetic rings and washers being co-axially
assembled in the shell body so that it not only attracts or captures the ferrous
particles but also retains them inside and, the said filtration system being provided
with an improved geometry whose whole assembly can be disassembled to remove
the collected particles and can also be re-used during the serVice of the filtration
system,
The ring magnet being more in internal diameter than that of washer along with coaxial
assembly of the magnetic rings and washers in the shell body facilitates the
attraction or capture of the ferrous particles and also helps it retaining the ferrous
particles.
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The system is being provided with provision such that the whole assembly can be
disassembled to remove the collected particles and then re-used during the service
of the filtration system.
As shown in Figure 1 which is assembled half-section view of the strainer, (101) is
the ring magnet and (102) is the non-magnetic washer. Threaded washer (105) is
attached with the filtration mesh and hence, it is one body (103). (104) is the shell
body. The ring magnet and washer are co-axially assembled in shell body (104).
Magnetic rings and non-magnetic washers are assembled alternatively in the shell
body as shown in Figures 1.
The hydraulic pump sucks the oil from tank, fluid enters through the strainer and
passes through assembly of ring magnets and washers. Any ferrous particle in the
oil flow channel gets trapped in between the cavity. External threads on (103) and
the internal threads of (104) are fastened together as show in the figure 1. This
provides mating of (103) and (104). It also constrains the motion of (101) and (102).
Multiple cavities are formed by the assembly of magnetic ring (101), washer (102),
magnetic ring (101) and so on. If ferrous particle is not trapped in the first cavity, it
will get trapped in the next consecutive cavities.
Figure 2 provides tentative working of invented strainer and shows working of the
strainer in detail.
One of the objectives of the present invention therefore is to provide a magnetic
suction filtration system having a geometry with an improved capability of filtering
foreign ferrous matter such as debris, resultant of the burrs, or material from welds
by providing a pocket formed by magnetic ring and non-magnetic washer.
Another objective of the invention is to capture the ferrous particles that are not
filtered by the strainer mesh. They are collected in the pocket. In Strainer, the
internal diameter of ring magnet being more than that of washer and the magnetic
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rings & washers being co-axially assembled in the shell body so that it not only
attracts or captures the ferrous particles but also retains it.
Yet another objective of the invention is to provide an improved strainer whose whole
assembly can be disassembled to remove the collected particles and can also be reused
during the service of the strainer.

WE CLAIM:
1. An improved suction strainer fitted with magnets to capture the ferrous dirt
contamination in construction industry by providing a pocket formed by magnetic
ring and non-magnetic washer, the said filtration system being provided with the
internal diameter of ring magnet being more than that of washer and the magnetic
rings and washers being co-axially assembled in the shell body so that it not only
attracts or captures the ferrous particles but also retains them inside and, the said
filtration system being provided with an improved geometry whose whole assembly
can be disassembled to remove the collected particles and can also be re-used
during the service of the filtration system.
2. An improved suction strainer fitted with magnets to capture the ferrous dirt
contamination in construction industry A magnetic suction filtration system as
claimed in claim 1, wherein the ring magnet being more in internal diameter than that
of washer along with co-axial assembly of the magnetic rings and washers in the
shell body facilitates the attraction or capture of the ferrous particles and also helps it
retaining the ferrous particles.
3. An improved suction strainer fitted with magnets to capture the ferrous dirt
contamination in construction industry as claimed in claim 1, wherein the system
is being provided with provision such that the whole assembly can be disassembled
to remove the collected particles and then re-used during the service of the filtration
system.