JPH0630243Y2 - filter - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a filter in which the flow of fluid passing through a filter mesh is reversed due to backwashing, and in particular, the fatigue of the filter mesh is improved. Regarding what you did.

[Prior Art] When a fluid is filtered through a filter mesh, impurities trapped on the surface of the mesh gradually accumulate to cause clogging, and finally the filter cannot be used. Therefore, it is necessary to periodically remove the clogging, but this regular maintenance often involves complicated manual work such as disassembly work.

Therefore, a technique has been developed in which impurities trapped on the surface of the filter mesh are automatically washed away without backing up and backwashing.

FIG. 5 is a principle diagram of a filter called a fully automatic self-continuous backwashing filter for fuel oil and lubricating oil, which is particularly used for diesel engines. In this method, oil is filtered in two stages. First, the oil is guided to the primary filter wire net 1 to capture impurities 2 in the oil to obtain clean oil.
A part of the clean oil is supplied to the engine, the remaining part is guided in the opposite direction of the other primary filter wire mesh 3, and the impurities 2 captured in advance are backwashed to obtain backwash oil.

Next, the backwash oil thus obtained by the primary filtration is guided to the secondary filter wire netting 4 to capture the impurities 2 to obtain the backwash filtered oil. This is sent to the sump tank or fuel tank. In addition, the remaining part of the clean oil obtained by the primary filtration is guided to another secondary filter wire mesh 5 in the reverse direction, and the impurities 2 captured in advance are backwashed to obtain a backwash oil. This backwash oil is combined with the backwash oil obtained by backwashing with the primary filter wire net 3. The impurities in this combined oil are appropriately discharged to the drain.

FIG. 6 shows an example of a filter structure constructed on the basis of the above principle. A large number of disc-shaped wire mesh filter elements 21 are stacked in the primary filtration chamber 6 and the secondary filtration chamber 7.

The oil containing impurities that has entered from the oil inflow portion 9 enters the gap portion 12 between the sleeve 10 and the distributor 8 according to the black arrow, passes through the hole of the sleeve, and the primary side element 11
After passing through and being filtered, it reaches the inside of the primary filtration chamber 6. The cleaned oil is sent to the engine side. On the other hand, the backwash oil that has passed through a part 13 of the primary side element 11 and is backwashed is sent to the secondary filtration chamber 7 through the hollow portion 16 in the distributor 8 and refiltered by the secondary side element 14.
It is returned to the fuel tank or the like through the return passage 17 in the distributor 8. A part 15 of the secondary element 14 is backwashed with clean oil. The impurities concentrated and stored in the secondary filtration chamber 7 are discharged to the outside of the system by periodic drainage. Reference numeral 18 is an air motor driven by air from outside the system to rotate the distributor 8.

Here, the primary filter wire meshes 1 and 3 and the secondary filter wire meshes 4 and 5 in FIG. 5 are respectively arranged in the primary side element 11 and a part 13 thereof and the secondary side element 14 and a part 15 thereof in FIG. Correspond.

FIG. 7 shows a plan view of a single element of the wire mesh filter element 21 described above, in which the filter wire mesh 24 is die-cast into a frame 25 divided into eight by the ribs 20. The filter wire mesh 24 is backed up by a backup wire mesh having a coarser mesh when necessary. Eight columnar filtration chambers are formed by stacking these.
22 is a fastening hole, and 23 is an insertion hole into the sleeve.

FIG. 2 shows that two filter elements 21 are laminated on both side walls 3
The upper half of the cross-sectional structure sandwiched by 3, 33 is shown. The behavior of the filter wire mesh 24 at the time of cleaning and backwashing will be described below with reference to this figure.

In the figure, during cleaning, the flow of dirty oil passes through the holes 26, 26 of the sleeve as shown by the solid arrows, and
It is guided into the columnar filtration chambers 28, 28 through the openings 27, 27 individually formed in the inner peripheral frame 25 of the 21, 21. Then, the openings pass through the filter wire nets 24, 24 and flow between the filter wire nets 24, 24 while being filtered, and as a result, as clean oil, openings formed integrally with the outer peripheral frames of the elements 21, 21.
From 29 to the filtration chamber 30.

On the other hand, at the time of backwashing, the clean oil flows in the direction completely opposite to that at the time of cleaning, as indicated by the dotted arrow.

In this way, when cleaning, the oil flows through the holes 26 → the filter mesh 24
→ Flows through the opening 29, and reversely when backwashing, and flows through the opening 29 → the filter wire mesh 24 → the hole 26. Therefore, as shown by the alternate long and short dash line position, the filter wire nets 24, 24 facing each other during cleaning are dented so as to approach each other, and bulge away from each other during backwashing.

[Problems to be solved by the invention] As described above, in a filter in which the flow of oil passing through the filter mesh is switched between washing and backwashing, the filter mesh is repeatedly dented or swollen each time it is switched. Will be deformed. This deformation causes fatigue to the filter net, and eventually, the backup net 31 having high strength is left as shown in FIG. 8 and the filter net 24 having weak strength is broken. In such a situation, the phenomenon has already become clear, and in reality, the filter network 24 and the backup network are
Although measures such as sintering 31 together have been taken, it has not been possible to prevent breakage under severe operating conditions, although the life is extended. Since this type of filter does not require disassembly and cleaning for a long time, it is usually impossible to detect the damage to the net. For this reason, there has been a problem that dirty oil is supplied to the engine.

An object of the present invention is to provide a filter capable of effectively preventing damage to the filter mesh due to fatigue by eliminating the above-mentioned drawbacks of the conventional technique by suppressing the repeated deformation of the filter mesh.

[Means for Solving Problems] In the filter of the present invention, the flow of the fluid passing through the filter wire mesh stretched over the frame alternates in the forward and reverse directions in order to remove impurities trapped in the filter wire mesh. It is configured to be repeatedly switched.

In such a configuration, a pressing member that presses the filter wire mesh without slack is provided in one of the flow directions of the fluid of the filter wire mesh.

[Operation] With the above configuration, the pressing member presses the filter wire mesh in the opposite direction without slack. Regardless of whether the fluid flow is switched to the forward direction or the reverse direction, the filter wire mesh is prevented from being dented or bulged each time. Therefore, even if switching is alternately repeated, the filter wire mesh is not damaged by metal fatigue.

[Embodiment] An embodiment of the present invention will be described below with reference to FIGS. 1 and 3 to 4.

FIG. 3 is a plan view of a main element according to an embodiment of the present invention. In particular, in the fully automatic self-continuous backwashing type filter described above, it is provided between meshed filter elements, for example, wire mesh filter elements. 2 illustrates an example of the expansion ring 40. For convenience of explanation, the expansion ring 40 will be described with reference to FIG.

The expansion ring 40 has an inner ring 41 and an outer ring 42 arranged concentrically, and the inner ring 41 and the outer ring 42 are connected by a large number of radially extending connecting members 43. A spherical body 44 as a pressing member is provided at each connection point between the connecting member 43 and the inner ring 41 and the outer ring 42. The pressing member is not limited to the spherical member. These spheres 44 are arranged in the gaps formed between the filter wire nets 24, 24 of the filter elements 21, 21 to be stacked, spread the filter wire nets 24, 24 apart from each other, and are stretched on the frame 25. Wire mesh 24
It is designed to remove the slack of.

By the way, when the filter elements 21 are stacked, eight filtration chambers 45 are formed between the elements 21 and 21 by the ribs 20.

The filter wire mesh surface 24 of each filtration chamber 45 facing each other is further divided into four by the crosspiece 46. As shown in FIG. 1, the above-described sphere 44 is arranged at the substantially central position of each of the four wire mesh surfaces 24 divided into four.

The diameter of the sphere 44 is a pressing force against the pressure fluctuation caused by the reversal of the oil flow, and is set to a size sufficient to spread the filter wire nets 24, 24 outward of the filtration chamber. However, the tip of the sphere must not be so small that it blocks the wire net 24 and that the wire net is damaged by the pressing force. When the filter wire mesh 24 is lined with a backup wire mesh, it is desirable to press from the backup wire mesh side in order to protect the filter wire mesh 24.

Further, the inner ring 41, the outer ring 42, and the connecting member 43 to which the sphere 44 is attached
Has a flat shape so that the filter elements 21, 21 which are stacked by contacting the wire net 24 or between the frames 25 do not float. The cut portion of the outer ring 42 is the escape of the fastening hole 22. The expansion ring 40 described above can be formed integrally with, for example, plastic.

As described above, since the divided filter wire nets 24 in the filtration chamber are pushed outward by the spheres 44 of the expansion ring 40, even if the direction of oil is switched during backwashing during washing, the filter Since the wire netting 24 is prevented from denting or swelling each time, the wire netting is not damaged by metal fatigue.

By using the expansion ring in this way, it is possible to press the wire mesh surface without merely making any change to the existing filter element simply by interposing it between the filter elements. Further, since the sphere 44 simultaneously presses the two wire mesh surfaces facing each other at the same time, the structure is simplified as compared with the case of pressing one surface at a time.

Further, in the above-mentioned embodiment, the fully automatic continuous backwash filter has been described as an example of the filter, but the present invention can be applied to any filter as long as the fluid flows back.
Further, the shape of the expansion ring is not limited to that of the embodiment.

[Advantage of the Invention] According to the present invention, since the filter mesh surface is pressed by the pressing member, the filter mesh does not deform even if the fluid flow is alternately switched repeatedly, and therefore, the damage caused by fatigue is prevented. It can be effectively prevented.

[Brief description of drawings]

FIG. 1 is a sectional view of an essential part of a laminated filter element showing an embodiment of a filter according to the present invention, FIG. 2 is a sectional view of an essential part of a conventional example, and FIG. 3 is an embodiment of a filter according to the present invention. FIG. 4 is a plan view of an expansion ring used in the present invention, FIG. 4 is an exploded plan view of the same laminated filter element, and FIG. 5 is a principle view of a conventional fully automatic self-continuous backwash filter example using a laminated filter element. FIG. 7 is a structural diagram of the same as above, FIG. 7 is a plan view of a single filter element, and FIG. 8 is an explanatory view showing damage of a filter wire mesh due to metal fatigue. In the figure, 24 is a filter wire mesh, 25 is a frame, and 44 is a sphere as a pressing member.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Office reference number FI technical display location B01D 29/39 29/62 7112-4D B01D 29/34 A

Claims (1)

[Scope of utility model registration request] 1. A filter wire mesh fluid in which a flow of a fluid passing through a filter wire mesh stretched over a frame is alternately switched between a forward direction and a reverse direction in order to remove impurities trapped in the filter wire mesh. A filter having a pressing member that presses the filter wire mesh without slack in one of the flow directions of the filter.