A self-balancing switching double-tube pressure line filter

Abstract

A self-balancing switching dual-cylinder pressure pipeline filter includes a filter head with a differential pressure transmitter mounted on its upper side. A working filter tank and a spare filter tank are mounted on the bottom of the filter head. A central hole is provided inside the filter head, and a valve cover is installed on the central hole. A switching valve, which mates with the valve cover, is located inside the central hole. The switching valve contains a balancing valve and a bypass valve. The balancing valve is integrated into the switching valve. The balancing valve handle is turned to 90° until the pressures of the working and spare filter tanks are balanced before the switching valve handle can be rotated. During normal operation, both the switching valve handle and the balancing valve handle are self-locking. The bypass valve is located within the switching valve. During system cold starts or when the filter element is severely clogged but not replaced in time, the bypass valve opens to prevent filter element crushing. This invention has a compact structure, centralized and convenient operation, and is very suitable for hydraulic or lubrication systems that require continuous operation and filter element replacement without shutdown.

Description

Technical Field

[0001] The invention relates to the technical field of hydraulic or lubrication system filtering, and in particular to a self-balancing switching double-tube pressure pipeline filter. Background Art

[0002] At present, the existing double-barrel pressure pipeline filters generally adopt independent designs for their switching valves and balancing valves. Most switching valves are equipped with limit grooves, but the switching valve handles have no self-locking design; and the balancing valves are mostly designed with an external ball valve plus a pipeline structure. The structure is not compact, the operation is not centralized, and it is easy to leak and malfunction. In addition, the balancing valve has a large number of external connecting parts, which poses a great risk of leakage. Summary of the invention

[0003] The purpose of the present invention is to provide a self-balancing switching double-tube pressure pipeline filter to solve the problems in the above-mentioned background technology.

[0004] The technical solution adopted to achieve the above-mentioned purpose is a self-balancing switching double-cylinder pressure pipeline filter, including a filter head, a pressure difference transmitter is installed on the upper side of the filter head, a working filter tank and a spare filter tank are installed on the bottom of the filter head, a middle hole is provided in the filter head, a valve cover is provided on the middle hole, a switching valve connected to the valve cover is provided in the middle hole, a balancing valve and a bypass valve are provided in the switching valve, and a bleed screw plug is also provided on the filter head, and an anti-drop positioning pin is provided on one side of the bleed screw plug.

[0005] Furthermore, the working filter tank and the spare filter tank have the same structure, both including a filter housing and a filter element, the filter housing is connected to the bottom of the filter head by threads, the filter element is connected to the central socket at the bottom of the filter head, and an oil drain plug is provided at the bottom of the filter housing.

[0006] Furthermore, the switching valve clearance fits in the middle hole of the filter head, and the filter head is also provided with an oil inlet, an oil outlet, a working filter housing oil inlet, a working filter element oil outlet, a spare filter housing oil inlet, and a spare filter element oil outlet that are connected to the middle hole; the switching valve includes a switching valve spool, and the switching valve spool is connected to the switching valve shaft through a key; the switching valve spool is fitted with a cylindrical clearance of the middle hole, and the middle cylindrical section of the switching valve spool divides the oil into an upstream chamber and a downstream chamber, the upstream chamber is respectively connected to the oil inlet and the working filter housing oil inlet, and the downstream The cavity is communicated with the oil outlet and the oil outlet of the working filter element respectively; the switching valve shaft is processed with A hole, B hole, C hole, D hole, E hole and a rectangular groove in sequence along the center line direction, the A hole and the B hole have a conical transition, the F hole is radially opened at the axial center of the B hole, and a circular shaft oil groove is provided at the corresponding outer diameter, O-rings are respectively provided on both sides of the shaft oil groove, the switching valve spool is radially opened with a G hole communicated with the shaft oil groove, the switching valve spool is provided with H hole, I hole, J hole and K hole, the H hole is communicated with the I hole, and the J hole is communicated with the K hole.

[0007] Furthermore, the balancing valve includes a balancing valve core, a balancing valve spring, a balancing valve cover, a top shaft, a reset spring and a balancing valve handle; the large end of the balancing valve core is placed in the A hole of the switching valve shaft, and the thin end passes through the B hole, the C hole, and the D hole to enter the E hole; the balancing valve spring is placed between the balancing valve core and the balancing valve cover, and is axially limited by a wire retaining ring; the reset spring is placed at the bottom of the E hole, and then the top shaft is installed, the balancing valve handle is connected to the switching valve shaft through a pin shaft, and the upper end of the top shaft is against the arc-shaped bottom of the balancing valve handle.

[0008] Furthermore, the valve cover is provided with a positioning pin and a rotating stopper, the rotating stopper is provided with a limiting arc groove, the positioning pin is assembled in the limiting arc groove, and the valve cover is also provided with two positioning seats.

[0009] Furthermore, the bypass valve includes a bypass valve seat, a bypass valve core, a bypass valve spring, and a bypass valve cover. The bypass valve core is placed at the bottom of the large hole end of the bypass valve seat; the bypass valve spring is placed between the bypass valve core and the bypass valve cover, and is axially limited by a wire retaining ring. Beneficial Effects

[0010] Compared with the prior art, the present invention has the following beneficial effects:

[0011] 1. The present invention integrates the balancing valve into the rotating shaft of the switching valve, which has a compact structure. Compared with the structural design of the external ball valve plus pipeline of the existing conventional double-tube pressure pipeline filter balancing valve, there is no external connection part, and the sealing risk is reduced to the minimum;

[0012] 2. The switching valve and the balancing valve of the present invention are designed to be self-locking. Before the balancing valve is opened, the balancing valve handle is stuck in the positioning seat on the valve cover, and the switching valve cannot be operated, which effectively avoids leakage and misoperation of the balancing valve that is not opened before switching. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] The present invention will be further described below in conjunction with the accompanying drawings.

[0014] Figure 1 is an axonometric view of the present invention;

[0015] Figure 2 It is a main structural diagram of the present invention;

[0016] Figure 3 It is a top view of the structure of the present invention;

[0017] Figure 4 yes Figure 2 Structural cross-section view at AA in the middle;

[0018] Figure 5 It is an assembly structure diagram of the switching valve core and the switching valve shaft in the present invention;

[0019] Figure 6 It is a structural side view of the switching valve core and the switching valve shaft in the present invention;

[0020] Figure 7 It is a structural diagram of the valve core of the switching valve in the present invention;

[0021] Figure 8 yes Figure 7 Structural cross-section view at the middle BB;

[0022] Fig. 9 yes Figure 7 Structural cross-section view at CC;

[0023] Fig.10 is a structural diagram of the switching valve in the present invention;

[0024] Fig.11 It is a schematic diagram of the rotation limit of the switch valve handle on the valve cover of the present invention;

[0025] Fig.12 It is a structural diagram of the bypass valve in the present invention. DETAILED DESCRIPTION

[0026] The present invention will be further described below in conjunction with embodiments and drawings.

[0027] like Figure 1-Figure 12As shown, a self-balancing switching double-barrel pressure pipeline filter includes a filter head 1, a pressure difference transmitter 2 is installed on the upper side of the filter head 1, a working filter tank 31 and a spare filter tank 32 are installed at the bottom of the filter head 1, a middle hole 101 is provided in the filter head 1, a valve cover 5 is provided on the middle hole 101, a switching valve 6 connected to the valve cover 5 is provided in the middle hole 101, a balancing valve 8 and a bypass valve 9 are provided in the switching valve 6, and a bleed screw plug 13 is also provided on the filter head 1, and an anti-drop positioning pin 14 is provided on one side of the bleed screw plug 13.

[0028] The working filter tank 31 and the spare filter tank 32 have the same structure, both including a filter housing 301 and a filter element 302. The filter housing 301 is connected to the bottom of the filter head 1 through threads, and the filter element 302 is connected to the central socket 102 at the bottom of the filter head 1. An oil drain plug 303 is provided at the bottom of the filter housing 301.

[0029] The switching valve 6 is clearance-fitted in the middle hole 101 of the filter head 1. The filter head 1 is also provided with an oil inlet 111, an oil outlet 112, a working filter housing oil inlet 121, a working filter element oil outlet 122, a spare filter housing oil inlet 131, and a spare filter element oil outlet 132, which are communicated with the middle hole 101. The switching valve 6 comprises a switching valve spool 601, and the switching valve spool 601 is connected to a switching valve shaft 602 via a key 603. The switching valve spool 601 is clearance-fitted with the cylindrical surface of the middle hole 101. The middle cylindrical section of the switching valve spool 601 divides the oil into an upstream cavity 604 and a downstream cavity 605. The upstream cavity 604 is respectively communicated with the oil inlet 111 and the working filter housing oil inlet 121, and the downstream cavity 605 is respectively communicated with the oil outlet 112. and communicated with the oil outlet 122 of the working filter element; the switching valve shaft 602 is processed with A hole 621, B hole 622, C hole 623, D hole 624, E hole 625 and a rectangular groove 626 in sequence along the center line direction; the A hole 621 and the B hole 622 have a conical transition, and an F hole 628 is radially opened at the axial center of the B hole 622, and a circular shaft oil groove 627 is provided at the corresponding outer diameter, and O-rings 805 are respectively provided on both sides of the shaft oil groove 627; a G hole 615 communicating with the shaft oil groove 627 is radially opened on the switching valve spool 601; the switching valve spool 601 is provided with H hole 611, I hole 612, J hole 613 and K hole 614; the H hole 611 is communicated with the I hole 612, and the J hole 613 is communicated with the K hole 614.

[0030] The balancing valve 8 includes a balancing valve core 804, a balancing valve spring 803, a balancing valve cover 802, a top shaft 807, a reset spring 806 and a balancing valve handle 809; the large end of the balancing valve core 804 is placed in the A hole 621 of the switching valve shaft, and the thin end passes through the B hole 622, the C hole 623, and the D hole 624 to enter the E hole 625; the balancing valve spring 803 is placed between the balancing valve core 804 and the balancing valve cover 802, and is axially limited by the wire retaining ring 801; the reset spring 806 is placed at the bottom of the E hole 625, and then the top shaft 807 is installed, the balancing valve handle 809 is connected to the switching valve shaft 602 through the pin 808, and the upper end of the top shaft 807 is against the arc-shaped bottom of the balancing valve handle 809.

[0031] The valve cover 5 is provided with a positioning pin 11 and a rotating block 10 . The rotating block 10 is provided with a limiting arc groove 1001 . The positioning pin 11 is assembled in the limiting arc groove 1001 . The valve cover 5 is also provided with two positioning seats 501 .

[0032] The bypass valve 9 includes a bypass valve seat 901, a bypass valve core 902, a bypass valve spring 903, and a bypass valve cover 904. The bypass valve core 902 is placed at the bottom of the large hole end of the bypass valve seat 901; the bypass valve spring 903 is placed between the bypass valve core 902 and the bypass valve cover 904, and is axially limited by a wire retaining ring 905.

[0033] In the present invention, a pressure differential transmitter 2 is installed on the upper side of the filter head 1, and a bleed screw plug 13 and a bleed screw plug anti-detachment positioning pin 14 are also provided on the filter head 1. A working filter tank 31 and a spare filter tank 32 are provided at the lower part of the filter head 1. The working filter tank 31 and the spare filter tank 32 have the same structure and both include a filter housing 301 and a filter element 302. The filter housing 301 is threadedly connected to the lower part of the filter head 1, and the filter element 302 is connected to the central socket 102 at the lower part of the filter head. An oil drain screw plug 303 is provided at the bottom of the filter housing 301. The switching valve 6 is arranged in the middle hole 101 of the filter head. There are 6 holes on the filter head that are connected with the middle hole. The 6 holes are respectively the oil inlet 111 and the oil outlet 112 at the top of the filter head 1, the working filter housing oil inlet 121 and the working filter element oil outlet 122 that are connected with the working filter tank 31, and the spare filter housing oil inlet 131 and the spare filter element oil outlet 132 that are connected with the spare filter tank 32. The switching valve core 601 is matched with the cylindrical clearance of the middle hole 101, and the middle cylindrical section of the switching valve core 601 divides the oil into an upstream cavity 604 and a downstream cavity 605. The oil inlet 111 is connected with the working filter housing oil inlet 121 to form the upstream cavity 604; the oil outlet 112 is connected with the working filter element oil outlet 122 to form the downstream cavity 605.

[0034] The switching valve 6 comprises a switching valve core 601 and a switching valve shaft 602, which are connected by a key 603; the switching valve shaft 602 is processed with A hole 621, B hole 622, C hole 623, D hole 624, E hole 625 and a rectangular groove 626 in sequence along the center line direction, the A hole 621 and the B hole 622 are tapered, the F hole 628 is radially opened at the axial center of the B hole 622, and a circular shaft oil groove 627 is provided at the corresponding outer diameter. The G hole 615 radially opened on the switching valve core 601 is connected to the shaft oil groove 627, and the H hole 611 on the switching valve core 601 is connected to the I hole 612, and the J hole 613 is connected to the K hole 614. Only the upper end, middle part and lower end of the switching valve core 601 are complete cylindrical sections. During operation, the oil pressures of the upper portion 607 of the switching valve core 601 and the downstream chamber 605 are equal, and the oil pressures of the bottom portion 606 and the upstream chamber 604 are equal, and the pressures of various parts of the switching valve are balanced.

[0035] The balancing valve 8 is arranged in the switching valve 6, the large end of the balancing valve core 804 is placed in the A hole 621 on the switching valve shaft 602, the thin rod end passes through the B hole 622, the C hole 623, and the D hole 624 to enter the E hole 625, the balancing valve spring 803 is placed between the balancing valve core 804 and the balancing valve cover 802, and the wire retaining ring 801 is axially limited. The reset spring 806 is placed at the bottom of the E hole 625, and then the top shaft 807 is installed. The balancing valve handle 809 is connected to the switching valve shaft 602 through the pin 808. The center of the pin 808 is on the non-balancing valve axis, slightly biased to the handle side, and the upper end of the top shaft 807 is against the arc bottom of the balancing valve handle 809. The O-rings 805 on both sides of the shaft oil groove 627 ensure that the shaft oil groove 627 is only connected to the balance valve opening oil path.

[0036] The filter head 1 is also provided with a valve cover 5, and a positioning pin 11 and a rotating block 10 are provided on the valve cover 5. The rotating block 10 is provided with a limiting arc groove 1001, and the positioning pin 11 is assembled in the limiting arc groove 1001. The valve cover 5 is also provided with two positioning seats 501. When the balancing valve 8 is closed, the balancing valve handle 809 is stuck in the positioning seat 501.

[0037] The bypass valve 9 is arranged in the middle of the switching valve 6, the bypass valve core 902 is placed at the bottom of the large hole end of the bypass valve seat 901, the bypass valve spring 903 is placed between the bypass valve core 902 and the bypass valve cover 904, and the wire retaining ring 905 is axially limited.

[0038] When the filter works normally, the oil in the system pipeline enters the filter housing 301 of the working filter tank 31 or the spare filter tank 31 through the oil inlet 111 of the filter head, and is then filtered from the outside to the inside through the filter element 302, and finally returns to the system pressure pipeline through the oil outlet 112, completing the oil filtration process.

[0039] As the working filter element continuously intercepts the system pollutants, the pressure difference between the upstream and downstream of the filter gradually increases until it reaches the alarm value of the pressure difference transmitter 2. The transmitter sends a signal to prompt the replacement of the filter element 302 and the switching of the working filter tank 31 and the spare filter tank 32. The process is as follows: first, loosen the bleed screw plug 13 on the side of the spare filter tank 32, retreat to the anti-drop positioning pin 14, pull up the balance valve handle 809 to 90°, and the balance valve oil circuit is opened. Since the arc-shaped bottom of the handle is designed as a cam structure, the handle During the rotation process, the return spring 806 is pressed down by the top shaft 807, and at the same time, the oil in the upstream chamber 604 of the working filter tank enters the annular oil groove 626 formed by the balance valve core 804 and the switch valve shaft B hole from the top shaft 804, and then flows into the spare filter housing inlet 131 through the F hole 628, the oil groove 627 and the switch valve core G hole 629, so that the pressure of the working filter tank 31 and the spare filter tank 32 is balanced. Only then can the switch valve handle 4 be rotated to another extreme position. When there is continuous oil outflow from the vent screw plug 13, tighten the screw plug and close the balance valve 8, that is, pull the balance valve handle 809 back. At this time, the balance valve handle 809 can automatically return to 0° under the action of the return spring 806 and be stuck in the safety seat 501.

[0040] When replacing the filter element, loosen the bleed screw plug 13 on the original working filter tank side to the positioning pin 14, open the oil drain screw plug 303 at the bottom of the filter housing, drain the oil, unscrew the filter housing 301 and rinse it, replace the filter element 302, screw the filter housing 301 back on, and tighten the bleed screw plug 13 and the oil drain screw plug 303.

[0041] When the system is cold started or the filter element is clogged to the point where the differential pressure transmitter 2 alarms, but the filter element is not replaced in time, when the differential pressure upstream and downstream of the filter reaches the bypass valve opening differential pressure, the bypass valve 9 opens to prevent the filter element from collapsing.

[0042] The present invention provides a self-balancing switching double-barrel pressure pipeline filter, which overcomes the shortcomings of the existing double-barrel pressure pipeline filter, such as the non-compact structural design and the non-centralized operation. The filter balancing valve is integrated in the switching valve, and the operation is centralized and simple. When the filter operates normally, the switching valve and the balancing valve both have a self-locking function; before the balancing valve is opened, the switching valve cannot be operated, which effectively avoids leakage and misoperation of the balancing valve not being opened before switching.

Claims

1. A self-balancing switching double-tube pressure pipeline filter, comprising a filter head (1), characterized in that: A pressure differential transmitter (2) is installed on the upper side of the filter head (1); a working filter tank (31) and a standby filter tank (32) are installed on the bottom of the filter head (1); a middle hole (101) is provided in the filter head (1); a valve cover (5) is provided on the middle hole (101); a switching valve (6) connected to the valve cover (5) is provided in the middle hole (101); a balancing valve (8) and a bypass valve (9) are provided in the switching valve (6); a venting screw plug (13) is also provided on the filter head (1); an anti-dropping positioning pin (14) is provided on one side of the venting screw plug (13); the working filter tank (31) and the standby filter tank (32) have the same structure, both comprising a filter housing (301) and a filter element (302); the filter housing (301) and the filter head are connected to each other. (1) is connected at the bottom by threads, the filter element (302) is connected to the central socket (102) at the bottom of the filter head (1), and the bottom of the filter housing (301) is provided with an oil drain plug (303); the switching valve (6) is loosely fitted in the middle hole (101) of the filter head (1), and the filter head (1) is also provided with an oil inlet (111), an oil outlet (112), a working filter housing oil inlet (121), a working filter element oil outlet (122), a spare filter housing oil inlet (131), and a spare filter element oil outlet (132) which are communicated with the middle hole (101); the switching valve (6) comprises a switching valve core (601), and the switching valve core (601) is connected to the switching valve shaft (602) via a key (603); the switching valve valve The cylindrical clearance of the core (601) and the middle hole (101) is matched, and the middle cylindrical section of the switching valve core (601) divides the oil into an upstream chamber (604) and a downstream chamber (605), the upstream chamber (604) is respectively communicated with the oil inlet (111) and the oil inlet (121) of the working filter housing, and the downstream chamber (605) is respectively communicated with the oil outlet (112) and the oil outlet (122) of the working filter element; the switching valve shaft (602) is processed with an A hole (621), a B hole (622), a C hole (623), a D hole (624), an E hole (625) and a rectangular groove (626) in sequence along the center line direction, the A hole (621) and the B hole (622) are tapered, and an F hole is radially opened at the axial center of the B hole (622). (628), and a circular shaft oil groove (627) is provided at the corresponding outer diameter, and O-rings (805) are provided on both sides of the shaft oil groove (627). A G hole (615) communicating with the shaft oil groove (627) is radially opened on the switching valve core (601), and the switching valve core (601) is provided with an H hole (611), an I hole (612), a J hole (613), and a K hole (614). The H hole (611) is communicated with the I hole (612), and the J hole (613) is communicated with the K hole (614). The balancing valve (8) comprises a balancing valve core (804), a balancing valve spring (803), a balancing valve cover (802), a top shaft (807), a return spring (806), and a balancing valve handle (809);The large end of the balancing valve core (804) is placed in the A hole (621) of the switching valve shaft, and the thin end passes through the B hole (622), the C hole (623), and the D hole (624) to enter the E hole (625); the balancing valve spring (803) is placed between the balancing valve core (804) and the balancing valve cover (802), and is axially limited by the wire retaining ring (801); the return spring (806) is placed at the bottom of the E hole (625), and then the top shaft (807) is installed. The valve handle (809) is connected to the switching valve shaft (602) via a pin shaft (808), and the upper end of the top shaft (807) abuts against the arc-shaped bottom of the balancing valve handle (809); the valve cover (5) is provided with a positioning pin (11) and a rotating block (10), and the rotating block (10) is provided with a limiting arc groove (1001), and the positioning pin (11) is assembled in the limiting arc groove (1001), and the valve cover (5) is also provided with two positioning seats (501). ; 2. A self-balancing switching double-tube pressure line filter according to claim 1, characterized in that: The bypass valve (9) comprises a bypass valve seat (901), a bypass valve core (902), a bypass valve spring (903), and a bypass valve cover (904); the bypass valve core (902) is disposed at the bottom of the large hole end of the bypass valve seat (901); the bypass valve spring (903) is disposed between the bypass valve core (902) and the bypass valve cover (904), and is axially limited by a wire retaining ring (905).

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