DE3613093C2 - - Google Patents

Description

The invention relates to a filter for Liquids, especially for the lubricating oil from Internal combustion engines, according to the generic term of Main claim.

Such filters are preferred in large quantities used in the automotive industry. A special one simple filter maintenance results from the fact that the Filter housing over the one arranged in the housing cover Tapping by simply screwing onto the  Tighten the threaded pipe socket of the connector body let, with the inflow channel and outflow channel at the same time of the connecting body to the raw liquid space and Clean liquid chamber of the housing are connected. Used filter housings are unscrewed and thrown away.

With simple filter maintenance, the aim is to Environment of the filter, for example the connector body not contaminated by leaking liquid and an unnecessary loss of the filter to be filtered or to avoid already filtered liquid. For this purpose, the known liquid filter DE-OS 33 44 568 a non-return valve that the Inlet openings of the housing cover and covers unwanted leakage of liquid to be filtered the raw liquid space, for example when unscrewing of the filter housing prevented. The one from the outlet channel for the drain channel branching off the pure liquid is at screwed filter housing from one to one Spindle through parts of the filter housing against one Valve seat pressed on, spring-loaded valve body locked. By unscrewing the filter housing from Connection body should open the valve and drain the liquid in the filter back into the Allow crankcase. But because of that Raw liquid space is emptied Raw liquid in the pure liquid channel and pollutes this. There is also no guarantee that that not raw liquid at the sealing ring between Connector body and housing cover emerges as soon as there the sealing pressure by unscrewing the Filter housing is lifted.  

From GB-PS 14 82 485 it is known on such can be fixed by screwing onto a connector body Filter housing in addition to the anti-return valve to arrange spring-loaded outlet check valve, which at Falling below the operating pressure Clean liquid chamber closed. Although this is Way the unwanted leakage of liquid from the Avoided filter housing. However, at Unscrew the filter housing raw liquid on the Seal between the connector body and the Exit the filter housing.

Finally, it is from DE-PS 34 03 077 for a differently constructed liquid filter, in which in two switchable firmly connected to the connector body Filter housings always open, to a drain channel connected ventilation holes are arranged, known to drain the liquid from the Filter housings against the direction of drainage through Provide spring-loaded check valves.

The object of the invention is to begin with known filters for liquids to improve constructively so that the leakage of Raw liquid on the sealing ring between the connector body and the filter housing when lifting the Sealing pressure is safely avoided.

According to the invention is the task in characterizing part of claim 1 listed Features solved.  

Will the supply of raw liquid to the filter for example by turning off the connected Internal combustion engine stopped, so open Check valves in the drain channel. The difference between the Connection body and the filter housing Liquid can flow out through the drain channel. Because the drain channel downstream of the filter operation Check valves not with liquid, but with air is filled, air penetrates through one of the two valves in the space between the filter housing and the Connector body while the liquid through the other check valve flows out. This enables one fast, easy draining of the liquid between filter housing and connector body.

According to a further proposal of the invention Inflow of air into the space between the connection body and filter housing and draining yourself there liquid is clearly specified, that the check valves in different geodetic height are arranged.

Another proposal of the invention relates to a such a filter, the sealing ring between Connection body and filter housing in one opposite the Horizontal inclined plane is arranged, and is characterized by the arrangement of the Mouth opening of a drainage duct section on the geodetically lowest point of the ring channel. This will the drainage of all the fluid between the Connection body and the filter housing guaranteed.

The following is an embodiment of the invention explained in more detail with reference to the drawings. Show it

Fig. 1 is a filter for liquids in longitudinal section and

Fig. 2 shows a section along the line 2-2 in FIG. 1.

The filter ( 10 ) shown as an exemplary embodiment is used to filter the lubricating oil of internal combustion engines. A connecting body ( 11 ) has an eccentrically arranged inflow channel ( 12 ) for the raw liquid, which opens into an annular channel ( 13 ).

A discharge channel ( 15 ) with a threaded pipe socket ( 14 ) for the pure liquid is provided centrally.

A cup-shaped filter housing ( 20 ) is closed on the lower end by a housing cover ( 21 ) which has a central threaded bore ( 22 ) in a collar ( 23 ) extending into the filter housing ( 20 ). The threaded bore ( 22 ) is used to screw onto the threaded pipe socket ( 14 ) of the connecting body ( 11 ).

Radially outside the threaded bore ( 22 ), a plurality of inflow openings ( 24 ), which are evenly distributed on a circular ring, are arranged in the housing cover ( 21 ) and are surrounded by a sealing ring ( 25 ) glued concentrically to the threaded pipe socket ( 14 ) on the housing cover ( 21 ). When the filter housing ( 20 ) with the housing cover ( 21 ) is screwed onto the threaded pipe socket ( 14 ), the sealing ring ( 25 ) rests sealingly on the end face of the connecting body ( 11 ).

A filter insert ( 30 ) arranged inside the filter housing ( 20 ) has an annular filter element ( 31 ) made of filter paper folded in a zigzag shape, which lies on its inner circumference against a perforated sheet jacket ( 32 ). On its upper end face, the filter element ( 31 ) is closed by an end plate ( 33 ) which has a cup-shaped depression ( 34 ) in the center. A spring plate ( 35 ) engages in the cup-shaped recess ( 34 ), which is supported by two spring tongues ( 36 ) on the bottom ( 26 ) of the filter housing ( 20 ).

The other end face of the filter element ( 31 ) is closed by an end plate ( 40 ) which has a substantially frustoconical extension ( 41 ) in the center. A valve housing ( 43 ) is fastened to the inwardly bent edge ( 42 ) of the extension ( 41 ), the upper, inwardly curved ring part ( 44 ) of which forms the valve seat for a disk-shaped valve body ( 45 ). Two tongues ( 46 ) extend downward from the ring part ( 44 ) towards the threaded bore ( 22 ). The ends of the tongues ( 46 ) are bent inwards and serve as abutments for a valve spring ( 47 ) which is designed as a helical compression spring and which is supported on the valve body ( 45 ) with its other end face. Valve housing ( 43 ), valve body ( 45 ) and valve spring ( 47 ) are parts of an outlet check valve ( 49 ) which functions in a manner to be described in more detail.

The filter insert ( 30 ) lies with its lower end plate ( 40 ) sealed against a valve ring disc ( 50 ) which covers the inflow openings ( 24 ) and forms a non-return valve ( 51 ) with them.

The filter insert ( 30 ) divides the interior of the filter housing into a raw liquid space ( 53 ) connected to the inflow openings ( 24 ) and a clean liquid space ( 54 ) connected to the threaded pipe socket ( 14 ).

The connecting body ( 11 ) has a drainage channel ( 60 ) which has a gradient everywhere and consists of drainage channel sections ( 63 , 63 ) which open out of the ring channel ( 13 ) at two spaced locations and are provided with the outlet openings ( 61 , 62 ). 64 ) and the common drain channel section ( 65 ). A valve device ( 70 ) with the check valves ( 71 , 72 ) controls the flow through the drain channel ( 65 ).

As can be seen particularly from FIG. 2, the outlet duct sections ( 63 , 64 ) are offset to a larger diameter in the region of their mouth openings ( 61 , 62 ) and are provided with ribs ( 66 ) projecting radially inwards and extending axially parallel. Each check valve has a valve ball ( 73 ) which, at operating pressure, is pressed against the force of the valve spring ( 74 ) against a shoulder in the outlet duct sections ( 63 , 64 ) designed as a valve seat ( 75 ). A cup disc ( 75 ) pressed in between the ribs ( 66 ) limits the path that the valve ball ( 73 ) can travel upwards under the pressure of the valve spring ( 74 ) when the connected internal combustion engine is at a standstill. Flow channels ( 77 ) thus remain between the wall of the drain channel ( 60 ) and the cup disk ( 76 ) and the valve ball ( 73 ).

In practical operation, lubricating oil passes through the inflow channel ( 12 ) into the ring channel ( 13 ) and through the inflow openings ( 24 ) into the raw liquid space ( 53 ) while lifting the valve ring disc ( 50 ). The oil then traverses the filter insert ( 30 ) radially from the outside inwards and thus reaches the clean liquid space ( 54 ). From there, the filtered oil passes the outlet check valve ( 49 ), the valve body ( 45 ) of which is lifted off the valve seat against the force of the valve spring ( 47 ). The filtered oil then flows through the outflow channel ( 15 ) to the lubrication points of the internal combustion engine.

The check valves ( 71 , 72 ) are closed by the pressurized oil, so that the drain channel ( 60 ), which is connected to the crankcase of the internal combustion engine, is separated from the oil circuit and can be filled with air.

When the internal combustion engine is switched off, the outlet check valve ( 49 ) and the return check valve ( 51 ) close. The check valves ( 71 , 72 ) open so that all oil that is in the spaces above the valve balls ( 73 ) of the check valves ( 71 , 72 ) and below the valve ring disc ( 50 ) of the non-return valve ( 71 ) passes through the drainage channel ( 60 ) can flow down to the crankcase. Air gets into the oil-free space through one of the check valves.

After the non-return valve ( 72 ) is arranged higher than the non-return valve ( 71 ), when the two non-return valves are opened, the oil to be drained will preferably flow out through the non-return valve ( 71 ) arranged below and the air preferably through the non-return valve ( 72 ) in penetrate the space freed from oil. The oil runs off quickly, so that the filter housing ( 20 ) with the housing cover ( 21 ) can be unscrewed and no more oil escapes when the pressure between the sealing ring ( 25 ) and the associated sealing surface of the connecting body ( 11 ) is removed.

Reference symbol list:

10 filters
11 connector body
12 inflow channel
13 ring channel
14 threaded pipe sockets
15 outflow channel
20 filter housing
21 housing cover
22 threaded hole
23 collar
24 inflow opening
25 sealing ring
26 bottom
30 filter insert
31 filter element
32 perforated sheet jacket
33 end plate
34 deepening
35 spring plates
36 spring tongues
40 end plate
41 approach
42 margin
43 valve housing
44 ring part
45 valve body
46 tongue
47 valve spring
49 Stop valve
50 valve washer
51 anti-return valve
53 Raw liquid room
54 Pure liquid room
60 drain channel
61 mouth opening
62 mouth opening
63 outlet duct section
64 outlet duct section
65 outlet duct section
66 ribs
70 valve device
71 check valve
72 check valve
73 valve ball
74 valve spring
75 valve seat
76 cup disc
77 flow channel

Claims (3)

1.Filter for liquids, in particular for the lubricating oil of internal combustion engines, with a connection body ( 11 ) which has an eccentrically arranged inflow channel ( 12 ) opening into an annular channel ( 13 ) for the raw liquid, a central outflow channel provided with threaded pipe socket ( 14 ) 15 ) for the pure liquid and in the filter mode by a valve device ( 71, 72 ) closed drain pipe ( 60 ) everywhere, with a filter housing ( 20 ) on the lower end closing the housing cover ( 21 ), which has a central threaded hole ( 22 ) for screwing onto the threaded pipe socket ( 14 ) of the connecting body ( 11 ) and radially outside of it has a concentric sealing ring ( 25 ) for sealing engagement with the connecting body ( 11 ) and with a non-return valve ( 51 ) connected to the annular channel ( 13 ) ) covered inflow openings ( 24 ) in the area between the threaded hole tion ( 22 ) and the sealing ring ( 25 ) is provided, and with a filter element ( 31 ), which the interior of the filter housing ( 20 ) in a with the inflow openings ( 24 ) in connection with the raw liquid space ( 53 ) and one on the threaded pipe socket ( 14 ) connected to the clean liquid chamber ( 54 ), characterized in that the clean liquid chamber ( 54 ) is closed by a spring-loaded outlet check valve ( 49 ) which is closed at the geodetic pressure resulting solely from the liquid column in the filter housing ( 20 ) and is opened at operating pressure such that the Discharge channel ( 60 ) opens out of the ring channel ( 13 ) at two spaced-apart orifices ( 61, 62 ), with outlet duct sections ( 63 , 64 ) adjoining the orifices ( 61 , 62 ) with check valves ( 71, ) arranged therein 72 ) which can be moved by spring force in the open position but in the closed position at operating pressure, and that the drain channel sections ( 63, 64 ) on the side facing away from the annular channel ( 13 ) of the check valves ( 71, 72 ) open into one another. 2. Filter for liquids according to claim 1, characterized in that the check valves ( 71, 72 ) are arranged at different geodetic heights. 3. Filter for liquids according to claim 1 or 2, wherein the sealing ring between the connecting body and the filter housing is arranged in a plane inclined to the horizontal, characterized by the arrangement of the mouth opening ( 61 or 62 ) of a drainage channel section ( 63 or 64 ) at the geodetically lowest point of the ring channel ( 13 ).