JP3907147B2 - Inline filter - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an inline filter.
[0002]
[Prior art]
Inline filters used in hydraulic equipment require maintenance work such as element cleaning and replacement, but there is a demand to reduce the maintenance frequency by reducing the maintenance frequency and making the maintenance work easier. In response to such a requirement, an inline filter described in Japanese Utility Model Laid-Open No. 4-87369 shown in FIGS. 5 and 6 will be described.
Note that the corresponding constituent elements of the present invention are indicated in parentheses after each constituent element, and are hereinafter referred to as constituent elements of the present invention.
In the figure, the hydraulic pump 1 and the direction switching valve 3 are connected by a high pressure inline filter (inline filter) 2 mounted directly on the discharge port 1 a of the hydraulic pump 1 and a piping 11. The element 4 is accommodated in the case 5 of the inline filter 2.
[0003]
[Problems to be solved by the invention]
However, the above prior art has the following problems.
Since the discharge oil from the discharge port 1a of the hydraulic pump 1 easily passes through the portion of the element 4 closer to the outlet passage 5a than the portion of the element 4 far from the outlet passage 5a formed in the case 5, the element 4 The filter function is not exhibited on average. Therefore, when the portion of the element 4 close to the outlet passage 2a is clogged, the filtration resistance of the element 4 increases even before the clogging of the portion of the element 4 far from the outlet passage 2a becomes a limit. For this reason, the maintenance frequency of cleaning and replacement of the element 4 increases, and the maintenance man-hour increases.
[0004]
The present invention has been made paying attention to the above-mentioned conventional problems, and an object thereof is to provide an in-line filter that reduces the frequency of maintenance such as cleaning and replacement of elements.
[0005]
[Means for solving the problems and effects]
In order to achieve the above object, an in-line filter according to a first aspect of the present invention is provided in a high-pressure line that connects a hydraulic pump to an actuator via a direction switching valve, and wastes high-pressure oil by an element housed inside the case. In an in-line filter for filtering, etc., a plurality of inlet passages communicating with an annular passage formed between the outer peripheral surface of the element and the case are arranged at a predetermined interval in a direction substantially perpendicular to the filtration surface of the element and in the axial direction of the element. Each of the cover members is formed in the case, fixed to the case, and abutted against the end of the element to support the element, and is formed with one outlet passage communicating with the inside of the element.
[0006]
According to the first invention, when pressure oil is supplied from a plurality of inlet passages formed in a direction substantially perpendicular to the filtration surface of the element, each inlet passage is formed at a predetermined interval in the axial direction of the element. Incoming pressure oil is filtered uniformly over the entire filtering surface of the element. Therefore, since the entire filtering surface of the element exhibits the filtering function on average, the maintenance frequency is reduced and the maintenance man-hour is reduced. The in-line filter has a function of filtering the pressure oil in the supply pipes connected to the plurality of inlet passages with an element and joining and discharging from one outlet passage, so that the confluence block and the in-line filter are separately provided. Therefore, the structure is compact.
[0007]
An in-line filter according to a second invention is the invention according to the first invention, wherein the in-line filter is interposed between the plurality of hydraulic pumps and one direction switching valve, and the plurality of inlet passages are connected to the discharge ports of the plurality of hydraulic pumps. Are connected to each other.
[0008]
According to the second invention, the discharge pressure oils of the plurality of hydraulic pumps are respectively supplied to the plurality of inlet passages of the inline filter and filtered by the element, and then merged and discharged from one outlet passage of the inline filter. The Therefore, although a method of dividing a large-capacity pump into a plurality of small-capacity pumps is often performed in terms of cost, an inline filter not only functions as an original filtering function but also functions as a merging block. The cost is also reduced.
[0009]
An in-line filter according to a third invention is characterized in that, in the first invention, the in-line filter is directly fixed to the hydraulic pump or the direction switching valve.
[0010]
According to the third aspect of the invention, compared to the case where an inline filter is arranged between the hydraulic pump and the direction switching valve, the hydraulic piping is not interrupted in the middle, and the mounting bracket for the inline filter, etc. As a result, the number and structure of the pipes are simplified, installation complexity is eliminated, and cost is reduced. In particular, when the in-line filter is directly fixed to the direction switching valve, it is not directly affected by the vibration of the engine or the pulsation of the hydraulic pump, and the durability is improved accordingly.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments according to the present invention will be described below with reference to FIGS.
First, a first application example of the first embodiment will be described with reference to FIGS. Components similar to those of the prior art shown in FIGS. 5 and 6 are denoted by the same reference numerals and description thereof is omitted. The inline filter 2 includes an element 4, a case 5, and a lid member 6. A storage chamber 5a for storing the element 4 is formed in the case 5, and a fitting hole 5b into which the one end 4a of the element 4 is fitted is formed at one end of the storage chamber 5a. The other end of the storage chamber 5a has an opening, and a fitting hole 5c into which the fitting portion 6b of the lid member 6 is inserted is provided in this opening. A fitting hole 6 a into which the other end 4 b of the element 4 is fitted is formed in the fitting portion 6 b of the lid member 6, and this fitting hole 6 a communicates with one outlet passage 6 c formed in the lid member 6. To do. The outlet passage 6 c communicates with the inside of the element 4 in a state where the element 4 is stored in the storage chamber 5 a of the case 5. The fitting portion between the other end portion 4 b of the element 4 and the fitting hole 6 a is sealed by the O-ring 8, and the fitting portion between the fitting portion 6 b and the fitting hole 5 c is sealed by the O-ring 9. When one end 4a of the element 4 is fitted in the fitting hole 5b at one end of the storage chamber 5a and the other end 4b is fitted in the fitting hole 6a in the lid member 6, the outer peripheral surface of the element 4 An annular passage 10 is formed between the inner wall of the storage chamber 5a. The lid member 6 is fixed to the case 5 with bolts 7.
The case 5 is formed with two inlet passages 5d and 5e communicating with the annular passage 10 at a predetermined interval in the axial direction of the element 4 in a direction substantially perpendicular to the filtration surface of the element 4. The inline filter 2 is connected to the screw hole 5f of the inline filter 2 from the hydraulic pump 1 side by a bolt (not shown) so that the two inlet passages 5d and 5e are connected to the two discharge ports 1a and 1b branched from the hydraulic pump 1, respectively. Tightened and fixed directly to the hydraulic pump 1. The two discharge ports 1a and 1b may be formed in separate blocks and fixed to the hydraulic pump 1.
[0012]
According to the first application example of the first embodiment, the discharge pressure oil of the hydraulic pump 1 is supplied to the inlet passages 5d and 5e of the in-line filter 2 from the two discharge ports 1a and 1b, respectively. After passing through and filtered, it is discharged into one outlet passage 6c.
Since each discharge pressure oil of the hydraulic pump 1 is supplied from two inlet passages 5d and 5e formed substantially perpendicular to the filtration surface of the element 4, the amount of pressure oil passing through the filtration surface of the element 4 is axial. Is equalized. Therefore, since the entire filtering surface of the element 4 exhibits the filtering function on average, the maintenance interval is extended and the maintenance man-hour is reduced.
Further, when the element 4 is cleaned or replaced, if the bolt 7 is loosened and the lid member 6 is removed in the direction of arrow A shown in FIG. 1, the other end 4b of the element 4 and the fitting hole 6a of the lid member 6 are fitted. Since the pressure contact force of the O-ring 8 acts on the joint portion, it is not necessary to touch the element 4 to which the oil 4 adheres by moving the element 4 together with the lid member 6 in the arrow A direction at the same time. Therefore, the element replacement work is facilitated.
In addition, since the inline filter 2 is directly fixed to the hydraulic pump 1, the hydraulic piping is not interrupted in the middle as compared with the case where the inline filter 2 is arranged between the hydraulic pump 1 and the direction switching valve 3. In addition, since the mounting bracket for the inline filter 2 is not necessary, the structure of the piping is simplified, the complexity of installation is eliminated, and the cost is reduced.
[0013]
Next, a second application example of the first embodiment will be described with reference to FIG. In addition, the same code | symbol is attached | subjected to the component similar to the 1st application example shown in FIG.1, 2, and the description is abbreviate | omitted.
In the first application example, the inline filter 2 is fixed to one hydraulic pump 1, but in this embodiment, the inline filter 2 is fixed to two hydraulic pumps 1A and 1B. Since other configurations are the same as those of the first application example, description thereof is omitted.
[0014]
According to the second application example, the discharge pressure oils of the two hydraulic pumps 1A and 1B are supplied to the two inlet passages 5d and 5e of the inline filter 2 and filtered by the element 4, respectively. The two outlet passages 6c join together and are discharged. Therefore, for example, when one large-capacity pump is divided into two small-capacity pumps in order to reduce costs, the in-line filter 2 serves not only the original filtration function but also the function of the merging block. Is not necessary, and the number of in-line filters 2 becomes one, so that the apparatus is made compact and the cost is reduced. Since other operations and effects are the same as those of the first application example, description thereof is omitted.
[0015]
A third application example of the first embodiment will be described with reference to FIG. Members similar to those in the first and second application examples shown in FIGS. 1 to 3 are denoted by the same reference numerals and description thereof is omitted.
In the first and second application examples, the inline filter 2 is fixed to one or two hydraulic pumps 1, 1 </ b> A, 1 </ b> B, but in the present application example, the inline filter 2 is fixed directly to the direction switching valve 3.
In the figure, the lid member 6 fixed to the case 5 is directly fixed to the direction switching valve 3 by a bolt (not shown). A portion of the outlet passage 6 c of the lid member 6 that is in contact with the direction switching valve 3 is sealed by an O-ring 12. Further, a flange 13 is fixed to the two inlet passages 5d and 5e by bolts (not shown) in the screw holes 5f shown in FIG. 2, and discharges of the two hydraulic pumps 1A and 1B are made to joint portions 13a and 13b formed in the flange 13. Pipe lines are connected by pipes 14a and 14b, respectively. When the pipes 14a and 14b are rubber hoses, hydraulic nipples are used for the joint portions 13a and 13b. Since other configurations are the same as those of the first and second application examples, description thereof is omitted.
[0016]
According to the third application example, the discharge hydraulic oil from the first hydraulic pump 1A is supplied to the inlet passage 5d of the inline filter 2 via the pipe 14a and the joint 13a, and the discharge hydraulic oil from the second hydraulic pump 1B is It is supplied to the inlet passage 5e of the in-line filter 2 via the pipe 14b and the joint portion 13b. The pressure oil supplied to the inlet passages 5 d and 5 e is filtered from the annular passage 10 through the element 4, then merged from one outlet passage 6 c and discharged to the direction switching valve 3. Therefore, since the in-line filter 2 serves not only as an original filtering function but also as a merging block, the apparatus is made compact and the cost is reduced.
Compared to the second application example, the third application example is not particularly affected by engine vibration or hydraulic pump pulsation because the in-line filter 2 is directly fixed to the directional switching valve 3, and is thus durable. Improves. Since other operations and effects are the same as those of the first and second application examples, description thereof is omitted.
[0017]
The second embodiment will be described with reference to FIG. Components similar to those of the application examples of the first embodiment shown in FIGS. 1 to 4 are denoted by the same reference numerals and description thereof is omitted.
In the first embodiment, the inline filter 2 is provided with two inlet passages 5d and 5e. However, in the second embodiment, the four inlet passages 5p, 5q, 5r and 5s have a predetermined interval in the axial direction, and The case 5 is provided at a position where the phase is sequentially shifted at a pitch of approximately 90 degrees in the circumferential direction. Since other configurations are the same as those of the first embodiment, description thereof is omitted.
[0018]
According to the second embodiment, the number of the inlet passages 5p to 5s is increased and pressure oil is supplied from the entire circumferential direction of the element 4 as compared with the first embodiment. The amount of pressure oil passing through the filter 4 is further equalized both in the axial direction and in the circumferential direction, so that the entire filtering surface of the element 4 exhibits a filtering function on average. For this reason, the effect that the maintenance interval is extended and the maintenance man-hour is reduced is remarkable.
In the second embodiment, the inlet passages 5p, 5q, 5r, 5s are provided at positions where the phases are sequentially shifted at a pitch of approximately 90 degrees in the circumferential direction of the case 5 with a predetermined interval in the axial direction. However, the present invention is not limited to this, and the predetermined interval in the axial direction does not need to be constant, and it is not necessary to sequentially shift the phase in the circumferential direction at a pitch of 90 degrees. It is only necessary that the pressure oil is supplied on average from all four circumferential directions.
[0019]
It should be noted that the inlet passages 5d, 5e, 5p to 5s of the inline filter 2 in each of the above embodiments may be plural, and the number is appropriately determined as necessary. Since other operations and effects are the same as those of the first embodiment, description thereof is omitted.
[0020]
As mentioned above, according to this invention, since all the filtration surfaces of an element exhibit the filtration function on average, maintenance frequency reduces and maintenance man-hours reduce. The in-line filter has a function of filtering the pressure oil in the supply pipes connected to a plurality of inlet passages with an element and joining them from one outlet passage, so it is necessary to separately provide a confluence block and an in-line filter. There is no, and the structure becomes compact.
[Brief description of the drawings]
FIG. 1 is a diagram illustrating a first application example of a first embodiment according to the invention.
2 is a bottom view of the inline filter shown in FIG. 1. FIG.
FIG. 3 is a diagram illustrating a second application example of the first embodiment according to the invention.
FIG. 4 is a diagram illustrating a third application example of the first embodiment according to the invention.
FIG. 5 is a diagram showing a second embodiment according to the present invention.
FIG. 6 is a diagram showing a conventional technique.
7 is a cross-sectional view taken along the line AA in FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1; Hydraulic pump, 1A; 1st hydraulic pump, 1B; 2nd hydraulic pump, 1a, 1b; Discharge port, 2; In-line filter, 3; Directional switching valve, 4; Element, 4a: One end, 4b; Part, 5; case,, 5a; storage chamber, 5b; fitting hole, 5c; fitting hole, 5d, 5e, 5p to 5s; inlet passage, 6; lid member, 6a; fitting hole, 6b; Shaft, 6c; outlet passage, 7; bolt, 8; O-ring, 9; O-ring, 10; annular passage, 13; flange, 13a, 13b;

Claims (3)

In an in-line filter that is installed in a high-pressure pipe that connects a hydraulic pump to an actuator via a direction switching valve, and that filters high-pressure oil debris by an element housed inside the case.
A plurality of inlet passages (5d, 5e, 5p to 5s) communicating with the annular passage (10) formed between the outer peripheral surface of the element (4) and the case (5) are substantially connected to the filtering surface of the element (4). Formed on the case (5) at a predetermined interval in the axial direction of the element (4) in a right angle direction, fixed to the case (5) and abutted against the end of the element (4) The in-line filter is characterized in that a single outlet passage (6c) communicating with the inside of the element (4) is formed in the lid member (6) for supporting the above. The in-line filter according to claim 1, wherein the inline filter is interposed between the plurality of hydraulic pumps (1A, 1B) and the one direction switching valve (3), and has a plurality of inlet passages (5d, 5e, 5p to 5s). ) Is connected to each discharge port (1a, 1b) of the plurality of hydraulic pumps (1A, 1B). The in-line filter according to claim 1, wherein the in-line filter is directly fixed to the hydraulic pump (1) or the directional control valve (3).

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