JPS6240648Y2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to an automatic backwashing type filter. This invention relates to an automatic backwash filter that employs a flow path switching method using a piston mechanism.

B. Prior Art Various filters are used for the purpose of removing impurities and sludge mixed in fluids to be filtered such as fuel and lubricating oil. The filter elements of these filters become clogged over time, so as a means to prevent such clogging, the flow path of the fluid to be filtered is switched over time to backwash the filter elements. In many cases, a so-called backwash mechanism is provided. The automatic backwash filter is an indispensable auxiliary device for maintaining stable continuous operation, for example, when low-quality oil is used as fuel for diesel engines, and various types of filters are used to meet these demands. Automatic backwash filters equipped with a backwash mechanism are commercially available. However, since all conventional automatic backwash filters use a rotary filter element or a rotary switching valve as a component of the backwash mechanism, their overall structure is generally complicated and the filtration is difficult. It has been difficult to maintain the smoothness of the action and backwash action to a practically satisfactory level. Conventional automatic backwash filters also require a great deal of maintenance effort due to their structural complexity, making it difficult to obtain not only operational reliability but also economical operating conditions. There were inherent inconveniences that could not be overlooked.

B. Purpose of the invention The main purpose of the invention is to provide an automatic backwash filter that can solve the above-mentioned problems found in conventional automatic backwash filters.

Another main object of the present invention is to provide an automatic backwash type filtration system that does not use any rotating filtration member and has a simple structure and excellent stability in filtration and backwashing functions.

C. Structure of the invention The present invention is a filter of the type that automatically switches the flow path of the fluid to be filtered at predetermined time intervals and backwashes two filter elements alternately. An automatic switching valve 11 having a fixed stopper 12 that engages with a swing link 13 of an instantaneous switching mechanism.
and a guide member 1 that presses the swing link 13.
4, its pressurizing spring 15, and a differential piston mechanism 7, 7', two backwash valves 17, 17', a main body Grooves 45, 4 on the body
Valve mechanisms 6, 6' consisting of pistons 50, 50' and pressurizing springs 33, 33' forming the filter elements 1, 5';
This invention provides an automatic backwash type filter in which a non-rotating filtration and backwash mechanism consisting of internal chambers 2 and 2' are arranged symmetrically.

D. Example Hereinafter, the device of the present invention will be described in detail based on the example shown in FIG. In addition, in the following explanation, the device of the present invention is
All the components except for the automatic switching valve 11 and the instantaneous switching mechanism 3 are arranged symmetrically in sets of two, so for ease of understanding, the components located on the left side and the components common to the left and right are shown below. ′ (datsushiyu)
Components located on the right side that have the same functions as the components located on the left side are designated by reference numbers with a dash (').

First, the chambers 2 and 2' are equipped with filter elements 1 and 1' for filtering sludge mixed in the fluid to be filtered, for example, heavy oil used as fuel for diesel engines. The inlet 4 has passages 46, 46' and a valve mechanism 6,
6' communicates with the chambers 2, 2', and the outlet 5 for the fluid to be filtered communicates with the interior of the filter element 1, 1' via passages 47, 47'.
Two differential piston mechanisms 7, 7' are arranged symmetrically on the upper left and right sides of the device of the present invention, and inside the differential piston mechanisms 7, 7' there are three piston mechanisms with different pressure receiving areas. liquid chambers 8, 9, 10 and 8', 9', 1
0' are formed respectively. An automatic switching valve 11 is disposed between the differential piston mechanisms 7 and 7' so as to be able to move freely in conjunction with the reciprocating motion of the differential piston mechanisms 7 and 7'. The provided stopper 12 is a swingable link 1
3 and presses the link 13, and a pressure spring 15 of the guide member 14.
The left and right ends of the automatic switching valve 11 extend into the third liquid chambers 10 and 10' of the differential piston mechanisms 7 and 7', respectively, and spacing springs 16 and 1 are provided at the left and right ends.
6' is fixed.

Further, below the differential piston mechanisms 7, 7', there are pressure springs 18, which bias the pistons 28, 28' of the two backwash valves 17, 17', respectively.
18' are arranged symmetrically, and further below the backwash valves 17, 17' are pistons 50, 50' having grooves 45, 45' and a pressure spring 3.
Valve mechanisms 6 and 6' consisting of valve mechanisms 3 and 33' are arranged symmetrically. Chambers 2, 2' containing filter elements 1, 1' are arranged below the valve mechanisms 6, 6', and a drain valve 1 for discharging sludge is installed at the bottom of the chambers 2, 2'.
9 and 19' are mounted symmetrically. The first liquid chambers 8, 8' formed on the outside of the differential piston mechanisms 7, 7' include passages 20, 20', check valves 21,
21', throttle valve 22, 22', passage 23, 23',
It communicates with the automatic switching valve 11 and, via the common passage 24, with a passage 47 leading to the outlet 5 of the fluid to be filtered.

A second piston mechanism formed in the differential piston mechanism 7, 7'
The liquid chambers 9, 9' have a smaller pressure receiving area than the first liquid chambers 8, 8', and the second liquid chambers 9, 9' have throttle valves 26, 26', passages 27, 27. ', and the liquid chambers 29, 2 formed on the left and right sides of the pistons 28, 28' of the backwash valves 17, 17' via the passages 25, 25'.
9' and the liquid chambers 30, 30'. The liquid chambers 29, 29' have a larger pressure receiving area than the liquid chambers 30, 30'.

In the drawings, openings designated by the symbol D with a suffix indicate drain outlets, and each of the openings D is connected to an atmospheric pressure release tank (not shown). The backwash valves 17, 17' are equipped with pressure springs 18, 18' on the outside that urge the pistons 28, 28' of the backwash valve in the axial direction, and the movement of the pistons 28, 28' in the axial direction Passage 31,
It is configured to switch and control the flow path of the fluid to be filtered between 31' and the passages 32, 32'.

On the other hand, the liquid chambers 34, 34' formed on the outside of the valve mechanisms 6, 6' are connected to the passages 32, 32', the backwash valve 1
7, 17', passages 31, 31', and common passage 2
4 and communicates with a passage 47 leading to the outlet of the fluid to be filtered. Further, the passages 35, 35' whose opening and closing are controlled by the valve mechanisms 6, 6' are connected to the passage 47 leading to the outlet 5, and the passages 36, 36' are connected to the piping 3.
7 and 37' to hydraulic inlets 38 and 38' of drain valves 19 and 19', respectively. The drain valves 19, 19' are constructed by connecting drain valves 39, 39' provided at the upper part with pistons 40, 40' provided at the lower part thereof by shafts 41, 41'. , 40' are urged downward by pressure springs 42, 42'. The valve chambers 43, 43' formed in the upper part of the drain valves 19, 19' are connected to the passages 44, 43'.
44' and a sludge separation tank (not shown) via a pipe (not shown) connected to the passage.

The automatic backwash type filter according to the present invention having the above-mentioned structure performs the filtration of the fluid to be filtered and the filter element 1,
1' is switched over time, and the filtered fluid is continuously supplied to the outside of the system from the outlet 5.

The figure shows the filter element 1 in filtration operation and the other filter element 1' being backwashed by the fluid to be filtered introduced into the automatic backwashing filter. At this time, the piston 51' of the differential piston mechanism 7' moves into the second liquid chamber 9'.
The piston 51 of the other differential piston mechanism 7 is being pressed by the pressure of the pressurized fluid flowing into it and is rapidly moving to the right, and the piston 51 of the other differential piston mechanism 7 is gradually moving to the right in a timed operation. It's coming.

The fluid to be filtered introduced into the device of the present invention from the inlet 4 flows into the chamber 2 through the passage 46 and the groove 45 of the valve mechanism 6, and flows into the filter element 1.
After being filtered, the water is sent to the outlet 5 and supplied to external equipment (not shown). In the illustrated state, the automatic switching valve 11 is located toward the left, that is, toward the differential piston mechanism 7, and a portion of the pressurized fluid flows through the common passage 24, the passage 23, and the throttle valve 22.
The liquid flows through the liquid chamber 8 into the first liquid chamber 8, which has a larger pressure receiving area than the second liquid chamber 9, and gradually moves the piston 51 to the right. Due to the movement of the piston 51, the pressurized fluid sealed in the second liquid chamber 9 is discharged to the common passage 24 side through the throttle valve 26 and the passage 27. At this time, the pressurized fluid heading towards the first liquid chamber 8 and the pressurized fluid heading towards the common passage 24 from the second liquid chamber 9 merge in the common passage 24,
However, due to the difference in pressure receiving area of the piston 51, the piston 51 moves to the right even if the first liquid chamber 8 and the second liquid chamber 9 have the same pressure, and its speed is controlled by the throttle valve 22. be adjusted. On the other hand, backwash valve 17
When the same pressure is applied to the liquid chamber 29 and the liquid chamber 30, a force is generated to the left due to the difference in their pressure receiving areas, but a force is pushed to the right by the larger pressing force of the pressure spring 18. has been done. For this reason, the passage 32 communicates with the opening D ₀ , the piston 50 of the valve mechanism 6 is pressed by the pressure spring 33 and is positioned to the left, and the inlet 4 and chamber 2 of the fluid to be filtered are connected to the piston 50 . They communicate through a groove 45 provided therein. Also, the pressure oil inlet 3 of the drain valve 19
8 communicates with the passage D ₁ via a pipe 37 and a passage 36 and is maintained at atmospheric pressure. Therefore, the valve 39 of the valve mechanism 6 is in a closed state. On the other hand, the first liquid chamber 8' of the differential piston mechanism 7' is
It is in communication with the third liquid chamber 10' of the differential piston mechanism 7' and the opening _D3 via the passage 20', the check valve 21', and the automatic switching valve 11, and the second A portion of the pressurized fluid flows into the liquid chamber 9' from the vicinity of the outlet 5 via the common passage 24, the passage 27', and the throttle valve 26'. The piston 51' rapidly moves to the right due to the outflow of the pressurized fluid from the first liquid chamber 8' to the third liquid chamber 10' and the inflow of the pressurized fluid into the second liquid chamber 9'. Moving.

In addition, the liquid chamber 30' of the backwash valve 17' is connected to the throttle valve 2.
6' and the pressure drop in the second liquid chamber 9' due to the movement of the piston 51' of the differential piston mechanism 7', the liquid chamber 29 located on the opposite side with the piston 28' in between The pressure will be lower than '. In this way, the piston 28' of the backwash valve 17' compresses the pressure spring 18' and moves to the right. In the liquid chamber 34' of the valve mechanism 6', there is a common passage 2.
4. A portion of the pressurized fluid flows from the vicinity of the outlet 5 through the passage 31', the backwash valve 17', and the passage 32', and the pressurized fluid compresses the pressurizing spring 33' and causes the piston 50' to move. Move it to the left. In this way,
A passage 46' from the inlet 4 to the chamber 2' is closed by a piston 50', and the piston 40' of the drain valve 19' includes a passage 35', a groove 45' of the piston 50', a passage 36', and a pipe 37'. A part of the pressurized fluid flows through the supply port provided near the outlet 5, and the pressurized fluid flows into the pressurized spring 4.
2' opens the valve 39'. The pressure of the pressurized fluid thus supplied from the vicinity of the outlet 5 acts from the inside to the outside of the filter element 1', causing the filter element 1'
The sludge adhering to the outer circumferential surface of the tank and causing clogging is removed by the backwash flow, and the sludge is discharged into a sludge separation tank (not shown) through the drain valve 39' and the passage 44'.

When the rightward movement of the piston 51' fitted in the differential piston mechanism 7' is completed, the flow of pressurized fluid passing through the throttle valve 26' ends and the fluid in the backwash valve 17' The pressures in chamber 29' and liquid chamber 30' become equal. In this way, the piston 28' of the backwash valve 17' is urged by the pressurizing spring 18' and starts moving to the left, releasing the pressurized air sealed in the liquid chamber 34' of the valve mechanism 6'. The fluid is led from the passage 32' to the opening _D0 , and the piston 50' of the valve mechanism 6' is biased by the pressure spring 33' and begins to move to the right. For this reason, the piston 4 of the drain valve 19'
The pressurized fluid that was pressing down on the piston 50' is discharged from the opening _D1 through the pipe 37' and the passage 36', the drain valve 39' is closed, and the fluid is then discharged from the groove 4 of the piston 50'.
The passage 46' is opened via 5' and the backwashing operation is completed. In this way, the filter element 1' continues to filter the fluid to be filtered until the next backwashing operation is started.

In addition, the filter element 1 which is in filtration operation in the drawings starts backwashing operation in accordance with the following procedure. First, the piston 51 of the differential piston mechanism 7 whose moving speed is adjusted by the throttle valve 22 is the first piston.
When the piston 51 gradually moves to the right due to the inflow of pressurized fluid into the liquid chamber 8, the piston 51 compresses the interposed spring 16, and uses the compression force of the interposed spring 16 to operate the automatic switching valve 11. Displace it to the right. When the link 13 of the instantaneous switching mechanism 3 swings to a near vertical position due to the rightward displacement of the automatic switching valve 11,
Due to the repulsive force of the interposed spring 16, the automatic switching valve 11 momentarily closes the stopper 12 provided on the right side.
It moves to the contact portion 48 of. Therefore, the first liquid chamber 8 of the differential piston mechanism 7 has a check valve 21 and a passage 2.
3. The third liquid chamber 10 of the differential piston mechanism 7 communicates with the opening _D2 , while the second liquid chamber 9 of the differential piston mechanism 7 is connected to the outlet 5 through the throttle valve 26. A portion of the pressurized fluid flows in from near the piston 51, rapidly moving the piston 51 to the left. The moving speed of the piston 51 can be adjusted by the throttle valve 26. As the piston 51 moves to the left, the pressure in the liquid chambers 8 and 30 drops to a greater extent than the pressure in the liquid chamber 29 due to the action of the throttle valve 26, and the piston 28 of the backwash valve 17 moves to the left. and the pistons 50 of the valve mechanism 6 move to the right, and in conjunction with the movement of these pistons, the drain valve 39 opens.
opens. The filter element 1 thus enters a backwashing operation according to the same operating procedure as the filter element 1'. Furthermore, since the automatic switching valve 11 is located on the right side when backwashing of the filter element 1 is started, the first liquid chamber 8' of the differential piston mechanism 7' is supplied from the vicinity of the outlet 5. The pressurized fluid flows in through the common passage 24, the passage 23', and the throttle valve 22', and accordingly the piston 5
1' starts to gradually move leftward from the right end position. That is, filter elements 1, 1'
The filter alternately switches between filtering operation and backwashing operation, and continuously sends the fluid to be filtered to equipment outside the system.

As is clear from the above description, in the device of the present invention, two filters are arranged symmetrically.
Filtration and backwashing operations are automatically repeated for each element at regular time intervals. The filtration time and backwash time are determined by the throttle valves 22, 26, and throttle valve 2.
The backwashing operation can be adjusted by adjusting the flow rate of the pressurized fluid by means 2' and 26', but it is desirable to repeat the backwashing operation at a rate of 2 to 3 seconds every 5 to 10 minutes, for example.

The filter element can be freely selected from commercially available products according to the characteristics of the fluid to be filtered, but a notch wire type filter with high backwashing effect or a perforated plate type filter with many small diameter taper holes can be used. It is preferable to use elements.

E. Effect of the invention The device of the invention has interposed springs 16 and 1 at both ends.
Automatic switching valve 11 and instantaneous switching mechanism 3 equipped with 6'
Since the flow path of the pressurized fluid is automatically switched between the filtration operation and the backwash operation using

Furthermore, in the device of the present invention, the filter elements 1 and 1' alternately and automatically repeat the backwashing operation and the filtration operation at predetermined time intervals, and one filter element is in the backwashing state. Since the fluid to be filtered is continuously filtered by the other filter element at a certain time, the device of the present invention is equipped with a simultaneous backwash prevention mechanism, and the fluid is discharged out of the system from the outlet 5. It can guarantee stable continuous flow function and contaminant removal function for pressurized fluid. On the other hand, when starting the backwash operation, the valve mechanism 6
or when the piston 50 or 50' of 6' compresses the pressurizing spring 33 or 33' and moves inwardly, after the passage of pressurized fluid from the inlet 4 to the chamber 2 or 2' is closed, the drain valve 39
or 39' opens, and furthermore, at the end of the backwashing operation, the drain valve 39 or 39' closes prior to opening the passage for the pressurized fluid, contrary to the above, so that the drain valve 39 or 39' flows from the inlet 4 to the drain valve 39 or 39'. It is possible to reliably prevent unnecessary flow of pressurized fluid.

As is clear from the above explanation, the device of the present invention adopts a simple structure filtration/backwash switching mechanism that does not require rotation of the filter element, and is quick and
Reliable switching operation can be achieved. Therefore, the device of the present invention can be expected to have significant benefits over conventional devices in terms of reliability of operation and ease of maintenance.

The device of the present invention also eliminates the unavoidable increase in pressurized fluid consumption in conventional automatic backwash filters that perform continuous backwash operation, and the increase in pressurized fluid consumption. In order to avoid increasing the capacity of the pump or piping system to cope with the problem, the interval between backwash operations and the backwash operation time are adjusted using a throttle valve, so it is possible to avoid the need for short-term backwash operations. It is only necessary to increase the flow rate of the pressurized fluid. Therefore, a good backwashing effect can be achieved with low pressurized fluid consumption.

[Brief explanation of the drawing]

FIG. 1 is a partially cutaway front view illustrating the device of the present invention. 1, 1'...filter element, 2, 2'...
...Chamber, 6,6'...Valve mechanism, 7,7'...
...differential piston mechanism, 17, 17'...backwash valve, 11...automatic switching valve, 3...instantaneous switching mechanism,
19, 19'... Drain valve, 21, 21'... Check valve, 22, 22', 26, 26'... Throttle valve.

Claims (1)

[Scope of utility model registration request] It is a type of filter that automatically switches the flow path of the fluid to be filtered at predetermined time intervals to alternately backwash two filter elements, and has a swing link of an instantaneous switching mechanism described later at one end of the valve body. An automatic switching valve consisting of a fixed stopper to be engaged, a guide member that presses the swing link, its pressurizing spring, and a differential piston mechanism, sandwiching an instantaneous switching mechanism that interlocks with the automatic switching valve. On both sides, there are two backwash valves, a valve mechanism consisting of a piston formed with a groove in the body of the main body and a pressurizing spring, and a non-rotating filtration and backwash mechanism consisting of an internal chamber of the filter element. An automatic backwash filter characterized by its symmetrical arrangement.