US2348651A - Filter - Google Patents

Description

May 9, 1944. c. G. scHELLY FILTER Filed June 28. 1941 Patented May 9, 1944 FILTER Cyril G. Schelly, WebsterV Groves, Mo., assigner to Business Collaborators, Inc., St. Louis, Mo., a corporation oi' Missouri Application June 28, 1941, Serial No. 400,201

(Ci. 21o-140) 19 Claims.

This invention relates to filters, and with regard to certain more speclc features. to indicating oil illters, particularly for automotive use, and is an improvement upon the invention disclosed in my United States patent application Serial No. 380,036, tiled February 21, 1941, for Filter.

Among the several objects of the invention may be noted the provision of an oil niter for use on automotive engines and the like which automatically and at all times indicates the condition of the ltering material therein; the provision of a device of the class described which gives a continuous visual indication or warning of said condition as long as the material is still useful, and a. nal different warning when the usefulness of the illtering material has been substantially exhausted: the provision of a device of this class in which theoperation is substantially damped against the eiiect of outside oscillations of the vehicle on which it is mounted: the provision of a device o! this class which while simple in form provides i'or ready renewal of illter material cartridges; the provision of simple means for increasing the steadiness of operation of the inclicating means; the provision of a filter of the class described in which indicating action responsive to cartridge weight is accurate; and the provision of a device of the class described which includes by-passing means insuring oil circulation under conditions of exceptionally high viscosity. Other objects will be in part obvious and in part pointed out hereinafter.

The invention accordingly comprises the elements and combinations of elements, features of construction, and arrangements of parts which will be exemplied in the structures hereinafter described. and the scope of the application oi which will be indicated in the following claims.

In the accompanying drawing, in which is illustrated one of various possible embodiments of the invention,

Fig. 1 is a vertical section;

Fig. 2 is a horizontal section taken on line 2--2 of Fig. i, looking upward; and,

Fig. 3 is a horizontal section taken on line 3-3 of Fig. l, looking downward. and enlarged.

Similar reference characters indicate corre- .spending parts throughout the several views of the drawing.

In. the present application. like numerals have been used to designate parts similar to those in seid prior application, wherever this appears to be usei'ul.`

Filtering units for automotive engines each ordinarily consist of a, casing carrying a filtering cartridge which is renewable from time to time. This cartridge consists of a suitable plug of filtering material, such as waste or the like, through which passes the oil to be filtered. From time to time the cartridge needs to be renewed because of the clogging eiect of impurities that are caught in it. Since engine operating conditions vary widely, the impurities in the oil passing through the cartridge also vary widely, and therefore cartridges clog at different rates, and reach the ends of their usefulness at different and unforeseen times. An operator has no means for knowing whether a cartridge is still in useful condition, and the practice has heretofore been to recommend a change oi cartridges upon an arbitrary mileage basis. This is unsatisfactory, and the present invention serves to provide means for continuously indicating to the operator the state of the cartridge in use.

Referring now more particularly to Fig. 1, there is shown at numeral I a casing which is mounted by a bracket, preferably near the engine or the like which the device serves. This casing has attached at its top a cover 3 to which is connected an oil inlet 5 leading from the engine oil pump. An outlet line 1 is also connected to said cover and returns oil to the engine sump. The high location of this outlet 'I in the cover 3, above the uppermost level of a cartridge to be described, constitutes one of the features of the present invention which is an improvement over said application, as will appear. At 911s indicated a drain plug at the bottom of the casing I.

The cover 3 is made with a sleeve or guide II in which moves a hollow slider cap I3. The slider is closed by a top I2 but open at the bottom where it is provided with screw threads I4. Connecting the oil inlet line 5 with the hollow slider I3 is a flexible hollow hose or leader I5. This leader should preferably be composed of flexible, oilresistant material such as synthetic rubber which is now available. A known trade-mark for a suitable synthetic rubber material is neoprene." The term ilexifble is meant herein to cover cases wherein movabllity of the end of leader I5 (at I'l) is accomplished by freely jointed pipe sections or the like making up the leader.

The slider I3 is also provided with a number of bleeder holes 8i for the purpose of cross connectlng the interior of the container and the interior of the cap 39. This prevents trapping oi' uid in either compartment as the slider moves up and down, thus quickly balancing the pressure under operating conditions. It will be understood that instead of drilled holes, as shown for the connections 3|, these may be accomplished by milling or otherwise forming slots on the outside surface of the slider I3.

A connector L I1 forms the attachment between the ilexible tube I and the hollow slider cap I3. The end connected with the inlet 5 is provided with a connector L I3. Connectors I3 and I1 are metallic, the latter having one leg which slides vertically in a wire wicket 3, the twolegs of which are fastened in the 'head 3. Thus the slider I3 is prevented from rotating While the leader I5 may deflect.

The new shape of the hose I5 in this application is spiral, as indicated in Fig, 2, the same making one approximately 360 loop in passing from the fitting I5 to the ttlng I1. It lies substantially in a plane perpendicular to the axis of movement of the slider I3. 'I'his form oi hose loop provides a much higher degree oi' flexibility of the hose with a much lower degree of resistance to movement of the slider I3.

Threaded into the slider I3 and communicating with its interior is a ball check relief valve 1I, which, under conditions of excessive pressure in the hollow interior o! the slider I3, will relieve oil under pressure to the interior of the tank I from whence it may escape directly out of the outlet 1, without passing through the filter elements of the device. 'This also is a new feature of the present apparatus over that shown in said application.

As stated, the slider I3 is closed in at the top, but it is open at the bottom to receive the threaded end of a pipe 2l which extends to form a flared, foraminated cone 23 on the inside of a illter cartridge. The cartridge is indicated generally at C. The lower end of the cone 23 is connected with a false bottom 25, which in turn is connected to a cylindrlc shell 21 which is enclosed at its upper end by a foramious cover 23. It is to be understood that the cone is only one of various shapes that could be used to provide a ilare, and, furthermore, the device would retain its other advantages without that due to the iiare at 23.

Beneath the false bottom or diaphragm 25 is the true bottom 3l oi the cartridge. which normally is positioned to leave a substantial space 33 between it and the lower head 35 oi' the container. However, the peripheral clearance 31 between the cylindric portion 21 of the cartridge and the container I is limited. Between 23, 25, 21 and 23 is held iiltering material such as waste or the like 55.

Sealed to the top of the sleeve II by screw threads is a transparent sealing and electrically insulating cap 33, composed of a transparent, plastic, or the like, such as the material known as Lucite The threaded connection is liquid tight and seals in the upper end oi' open guide I I.

Within the cap 33 is a compression spring 4I which rests upon the upper end of the guide sleeve II and reacts against a rotary, conducting indicator plate 43. The plate 43 is connected with the slider cap I3 by a conducting pin 45. The pin 45 is threaded in rigidly into the slider I3 but the plate 43 is rotary on the pin 45 and carries a conducting contact 31| which forms an extension reaching into a slot 32 in the Lucite" cover 33. In the slot 32 is a leaf-spring contact 34 which ls in electrical communication with wire contact 41. The contact 41 is in the battery circuit 43, including a signal 5I, the circuit returning ultimately through the cap 3, as indicated at 33. The purpose of the rotary connection between the disc 43 and the stem 45 is to provide for the possibility of relative motion between the cover 33 and guide I3 when the cover is screwed on. Thus the cap 33, contact 33, and disc 43 revolve as a unit during application of the cap, while the slider I3 with the pin 45 remains stationary.

It is to be understood that Where desirable con.. ducting parts of the vehicle may be included in circuit 43. Thus, when the plate 43 has descended to a point where it comes into engagement with the contact 34, as it may. the circuit 43 is closed to light the signal lamp 5I. Thus in addition to the plate 43 being visible through the cap 33 so as to give a constant visible indication of its position, the signal lamp 5I gives warning of a predetermined lowermost position.

Operation 0i' the device is as follows, referring to Fig. l:

Oil enters the line 5, passes through the ilexible connector I5 to the interior of the slider cap I3, from whence it passes down through the pipe 2| and into the enlarged space within the cone 23 and sump 3I. This space, being enlarged in cross section with respect to that within the pipe 2|, serves gradually to reduce the velocity oi' the oil so that most of its kinetic eiect is transformed into pressure which is exerted equally in all directions. By cartridge is meant the aggregate of parts 2|, 23, 25, 21, 23 and 3|, together with the contained waste 55. The oil then nds its way slowly through the foraminations 51 in cone 23. up through the waste 55 and out of the foraminations 53 in the cover 23. It then flows out over to the outlet 1 and back to the source.

Normally the spring 4I supports and balances the cartridge C when it is new, in an upper position such as shown. As solid o! amorphous material becomes clogged in the iiltering material 55, the cartridge gradually increases in weight which deiiects the spring 4I and depresses the visible conducting plate 43. The cartridge also increases in weight, due to any heavy materials which may gather in the sump 3l. Some materials are so heavy, such as detached metal bearing particles, that the slow upward current is not enough to support them, and it is the intention to have these also increase the measurable weight o1' the cartridge. While these particles do not contribute to direct deterioration of the filtering material, their unlimited accumulation in the cartridge is undesirable, because ultimately they will fill up the whole bottom, and it is imperative that they also be taken into account as indicating deterioration of the cartridge as a whole. As

the plate 43 descends, it gives a proportional indication of the condition of the cartridge, since the heavier the cartridge is by reason oi' foreign material it contains, the more it is clogged, necessarily.

Finally, if the visible warnings, given by depression of the member 43 are ignored, there is a final warning at the light 5I when the contact 33 engages the xed contact 34. This closes the circuit 43. The signal lamp 5I may be placed in any convenient location where the operator is likely tc see it, such as upon the instrument panel of the vehicle.

In operation, the restricted space between the cartridge C and the container I is lled with lubricant, as is also the space at the upper and lower ends. Since the cross section between the cylinders I and 21 is relatively limited in area, the effects of the vertical vibrations of the vehicle on cartridge C are damped out. That is to say, the arrangement of the cartridge C in the cylinder I is like that of a dash-pot piston for damping purposes against violent movements. This is due to the throttling action of any liquid which tends to suddenly be forced between the cylinders I and 21 by incipient downward movement of 3| on the oil beneath. However, this does not interfere with slow movement of oil as required by deflection of spring Il for weighing indications as the cartridge slowly descends.

In order accurately to guide the cartrldgein its axial movements without excessive friction, I provide guide pins or lugs 83. Thus, between the pins 33 and the slider I3, the cartridge is maintained in alignment during axial movement. Thus the action is at all times relatively free, including when an automobile in which the device is located is not on the level.

The fact that the outlet 1 ls high up in the head 3 assures that the liquid level is high enough at all times to cover all of the cartridge C. This has the effect of substantially reducing the variations in cartridge positions, since any surging of the liquid level in the device does not carry it below any part of the cartridge.

The highly flexible character of the spirally wound hose I5 makes the deflection of the slider I 3 quite accurately responsive to cartridge weight.

I1', as upon a winter morning, .the oil is so viscous or stiff that it builds up a large back pressure in attempting to pass through the filtering material 35, this pressure will open the check valve 'Il and by-pass the oil directly from the inlet, through the hose I5, slide I3, valve 1I and to the outlet 1, without being filtered. This con dition continues until the engine warms up the oil to a condition wherein the back pressure is reduced to a point where the check valve 'II recloses. Thereafter the oil passes through the ltering material 35.

The container I is supported from the head 3 by means of rotary draw studs 13 and wing nuts 15. Therefore, to replace a cartridge it is only necessary to loosen the nuts 15, swing out the studs 13 and, after loosening the lines from the connections 5 and 1, lift the cover 3. 'I'his exposes the cartridge C so that it may be unscrewed as a unit from threads Il. The wicket i prevents the slider from turning in view oi the L I1 passing through it. A new cartridge is then screwed into place. and the container reclosed and reconnected.

It should be observed that foreign material deposited in the cartridge C replaces clean oil which occupied the same space when the cartridge was fresh. Thus assuming that a new cartridge thoroughly soaked with clean oil weighs two pounds, and that after several thousand miles of normal operation it is found to weigh three and one-half pounds, the weight increase due to foreign material would seemingly only be one and one-half pounds. However, because in the total weight of the cartridge wet with clean oil, one pound would represent the weight of the oil and one pound the cartridge, the amount oi' foreign material removed when the cartridge weighs three and one-half pounds would be two and one-half pounds, because foreign substance has replaced clean oil. The spring 4I is calibrated accordingly.

From the above it will be seen that the objects of the invention are accomplished, namely, substantially complete submersion of the cartridge at all times in the oil which passes through the container I, so that any surging in the level of the oil under varying rates of flow will not substantially effect the buoyancy of the cartridge C.

Also, the new helical form of iiexlble hose Il provides for less interference with operation of the contact 30 by the weight of the cartridge. In addition there is the matter of the improved form of the wicket Il, the relief valve 1I, and the rotary plate 43 in connection with the contact 3II.

In view of the above. it will be seen that the several objects of the invention are achieved and other advantageous results attained.

As many changes could be made in the above constructions without departing from the scope of the invention, it is intended that all matter contained in the above description or shown in the acompanying drawing shall be interpreted as illustrative and not in a limiting sense.

I claim:

l. A filter comprising a cylindric container, a filtering cartridge in said container, a movable slider supporting said cartridge for movement, a guide i'or the slider, resilient means supporting the slider and cartridge, said slider having a communcation for introduction of iiuid ino the cartridge, said container having an oil inlet and an oil outlet. and a flexible tube connecting said inlet and the communicating portion of said slider, said tube consisting of a spiral loop, the general plane oi' which is normal to the direction of movement of said container.

2'. A filter comprising a cylindric container, an axially movable nltering cartridge in sa'd container. a movable slider supporting said cartridge for axial movement, a guide for the slider, resilient means supporting the slider and cartridge, said sider having a communication for introduction of duid into the cartridge, said container having an oil inlet and an oil outlet the latter being high enough to maintain a liquid level always above the cartridge, and a flexible tube connecting said inlet and the communicating portion of said slider and consisting of a spiral loop above the container. the general plane of which is norma! to the axis of said container.

3. A filter comprising a cylindric container, an axially movable filtering cartridge in said ccntainer, a movable slider supporting said cartridge for axial movement, a guide for the slider, re silient means supporting the slider and cartridge. said slider having a communication for introduction of fluid into the cartridge, said container having an oil inlet and an oil outlet the latter being high enough to maintain a liqu'd level always above the cartridge, a flexible tube connecting said inlet and the communicating portion of said slider and consisting of a spiral loop above the container, the general plane of which is -normal to the axis of said container, and a pressure release valve onnected to said slider for Felsmnressrmjm within the slider.

4. A filter comprising a cylindric container forming a chamber having an oil inlet and an cil outlet, a filtering cartridge in the container, resilient weighing means supported by the con tainer, said weghing means supporting ihc cartridge, a movable hollow oil conducting means forming a mechanical connection between the we ghing means and the cartridge which connection conducts oil to the cartridge and moves therewith, a flexible connection from said inlet to said hollow movable means for transmitting fluid thereto, a pressure relief valve communicating between said hollow movable means to the interior of the chamber and delivering to the outlet side of the cartridge, whereby excess pressure may be relieved t2 by-passjluid from the inlet, through said movable means to the outlet, without passing through said cartridge, and means operated as a result of the movement of the cartridge for indicating its position in the container.

5. A filter comprising a closed container having an inlet, an outlet and an opening for a slider, an axially movable filtering cartridge within the container subject to the force of gravity, a slider which is hollow within the container and having a communication with the interior of the cartridge and extending through said opening in the container, a guide for the slider, resilient means supporting the slider and cartridge in the container, a flexible connection between said inlet of the container and said slider, and a relief valve communicating when open between the interior of the slider and the interior of the container and delivering to the outlet side of the cartridge, and means operated as a result of the movement of the cartridge for indicating its position in the container.

6. A filter comprising a closed container having an inlet, an outlet and an opening for a slider, an axially movable filtering cartridge within the container subject to the force of gravity, a slider which is hollow within the container and having a communication with the interior of the cartridge and extending through said opening in the container, a flexible connection between said inlet oi' the container and said slider, a relief valve communicating when open between the interior of the slider and the interior of the container and delivering to the outlet side of the cartridge, a sealed cover on the container and covering said slider where it passes through the opening in the container, i` cuit, `and contact means in the signal circuit and within said cover operative as a result of a predetermined downward movement of the slider in response to the weight of said cartridge to close said signal circuit.

7. A filter comprising a container having an upper wall opening for a slider, a movable filtering cartridge therein, upward biasing means, a nonfrotary sliding means which is hollow within the container and having a part passing through said opening in the wall of the container and responsive to the eiect of gravity on said cartridge, a cover threaded to the container around said sliding means where it passes through the wall of the container, said cover having a slot, a signal circuit, an electrical contact in said circuit and located in the slot, and contact means extending from said slide into the slot and forming a second contact in said circuit, said extending contact being rotary with respect to said slide, whereby the cover may be rotated for removal despite the slot therein containing said contact, and a signal circuit controlled by said contacts.

8. A lter for fluids comprising a container having an inlet and an outlet, guide means therein, upwardbiasing supporting and weighing means connected with the container, a filtering cartridge in the container having an inlet and an outlet and guided for substantially vertical movement by the guide means and normally movably supported by said weighing means, a flexible connection between said inlets, said outlet of the container being at a high enough elevation with respect to the cartridge to maintain said cartridge entirely beneath the liquid level in the container in any of its various supported positions, and means operated as a result of the movement of the cartridge for indicating its position in the container.

9. A filter unit for iltering uuid comprising a container having an inlet and an outlet. a 6 movable filter cartridge in the container and having an inlet and an outlet, resilient means supporting the weight of the cartridge and deilecting in proportion to the Weight oi' the cartridge, a signal circuit, a switch means in the l circuit having a pair of contacts one of which is fixed in respect to the container and the other of which is connected to the cartridge for movement therewith, predetermined movement of the cartridge moving said movable contact into closed lo circuit position with respect to the ilxed contact. i0. A filter unit for ltering uid comprising a container having an inlet and an outlet, a movable filtering member containing a mass for filtering out and catching impurities from the fluid, said member having an inlet and an outlet on opposite sides of said mass, resilient spring means supporting said movable filtering member` from a point fixed with respect to the container and in equilibrium against the force of gravity, displaced positions of the filtering member with respect to said point being predetermined according to the weight of the filtering member and its contents, a connection between said resilient means and the filtering member for effecting said support, and freely flexible conduit means connecting said inlets for directing iluid to the filtering mass, said fluid passing through the mass and through the outlet of the filtering member to deposit impurities in the filtering mass, whereby said displaced positions with respect to the container are assumed by the filtering member according to weight, and means operated as a result of the movement of the ltering member for indicating its position with respect to said fixed point.

1l. A filter unit for filtering fluid comprising a container having an inlet and an outlet. a movable cartridge containing a filtering mass for lterlng out impurities from the fluid, said cartridge having an inlet and an outlet on opposite sides of said mass, resilient spring means supporting said cartridge and its included mass against gravity from a point fixed with respect to the container and to hold them in equilibrium, displaced positions of the filtering member with respect to said point being predetermined according to the weight of the cartridge and its contents, a supporting connection between said resilient means and the cartridge for eilecting support, freely flexible conduit means connecting said inlets for introducing to the cartridge contaminated uid in any of the displaced positions of the cartridge without applying substantial reaction on the cartridge which would affect the weight-movement relationship and means operated as a result of the movement of the cartridge for indicating its position with respect to said xed point.

12. A lter unit for filtering fluid comprising a container having an inlet and an outlet. a movable cartridge in the container and also having an inlet and an outlet, filtering material in the cartridge between the cartridge inlet and the outlet, resilient spring supporting means connected to the container at a fixed point, a connection between the cartridge and the resilient supporting means, said cartridge and contained material and impurities caught thereby being normally movable in the container in response to the pull of gravity to displaced positions which are predetermined with respect to said nxed point according to the weight ot the cartridge and its contents. said container carrying oil which surrounds the cartridge, the clearance between the sides o! the cartridge and the container being relatively small and substantially damping cartridge movements, a exible connector between the inlet oi' the container and the inlet of the cartridge for introducing oil into the cartridge inlet which iiows through the filtering material, then through the outlet oi' the cartridge, then into the volume of oil surrounding the cartridge, ilnally through the outlet in the container, and means in the cartridge adapted substantially to balance reactions due to oil entry and means operated as a result i the movement of the cartridge for indicating its position with respect to said ilxed point.

13. A filter unit for filtering fluid comprising a container having an inlet and an outlet, a movable cartridge in the container, filtering material in the cartridge, said cartridge having an inlet and an outlet on opposite sides 0f the filtering material whereby iluid is compelled to pass through the ltering material, means resiiiently supporting in the container from a xed point related thereto the cartridge and contained filtering material along with any impurities caught thereby. said resilient supporting means oenecting predeterminately with respect to the container according both to the weight o! the cartridge and contained material, a exible conduit connecting the inlet of the container with the inlet of the movable cartridge and means operated as a result of the movement of the cartridge for indicating the position oi' the cartridge with respect to said ilxed point.

14. An indicating oil filter unit for ltering fluid comprising an openable container, said container having an oil inlet and an oil outlet, a substantially vertical guide in the container, a hollow slide which is substantially vertically movable in said guide and having an oil inlet, a exible conduit connecting said inlets, resilient means supporting the slide against gravity, a cartridge having an oil outlet within the container, al hollow quick-detachable connection between the hollow slide and the cartridge inlet whereby Weight will be applied to the resilient means through said slide in order to deflect the resilient means in proportion both to the weight of the cartridge and any material therein, the quick-detachable connection between the cartridge and the slide being operable after the container is open for quick removal of the cartridge from the slide, whereby a similar new cartridge may quickly be attached to the slide and means operated as a result of the movement ot the slide for indicating the position of the cartridge in the container.

15. An oil lter unit for illtering oil comprising a container, said container having an oil inlet and an oil outlet, a filter cartridge having an inlet and an outlet and illtering material therein between said inlet and outlet, said cartridge being gradually movable up and down in the container and normally spaced from its bottom to provide space, a freely flexible conduit connector between said inlets, said container outlet being at an elevation in the container to bring about an elevation of oil in the container surrounding the cartridge, resilient spring means supporting said cartridge from a nxed point on the container in displaced positions winch with respect to said point are predetermined by the weight of the cartridge and its contents thus permitting a gradual downward movement thereof substantially independently of the liquid level in the container and in response to change of weight due to accretion of filtered material therein, the space between the container and the cartridge being such as substantially to damp vibratory motions of the cartridge in the container but permitting motion of gradual descent due to said change in weight and means operated as a result, of the movement of the cartridge for indicating the position of the cartridge with respeci; to said point.

16. A lter unit for filtering oil comprising a substantially vertical cylindric container having an oil inlet and an oil outlet, a substantially vertical cylindric movable cartridge in the container having an oil inlet and an oil outlet and carrying filtering material between its inlet and outlet, a freely flexible oil conduit means connecting said inlets, resilient means normally supporting the cartridge against gravity from a point xed with respect to the container but permitting slovvv downward movement thereof according to increase in weight thereof substantially independently of liquid level in the container and caused by accretion of filtered material therein, said outlet in the container being at such an elevation that a level of oil is carried in the container above the top of the cartridge, the clearance between the cartridge and the container being oi such an amount that said oil in the container functions substantially to damp. vibratory cartridge movements and means operated as a result o1 the movement of the cartridge lor indicating the position of the cartridge with respect to said point.

l?. A iilter unit for ltering fluid comprising a container including a transparent portion and having an inlet and an outlet, a movable lter cartridge in the container having an oil inlet and an outlet, spring means supporting the weight of the lter cartridge with respect to a point on the container and substantially independently of the liquid level in the container and deiiecting in proportion to the weight of said cartridge, means visible through said transparent portion and operated as a result of the movement of the cartridge for indicating the position of the cartridge with respect to said point and a ilexible conduit for conducting uid to the inlet of the cartridge from the inlet of the container.

18. A filter unit for ltering oil comprising a container having an oil inlet and an oil outlet.

a movable ltering cartridge in the container also having an oil inlet and an oil outlet in the container with illtering material between said inlet and outlet, said cartridge being subject to the force of gravity, resilient means supporting the cartridge against gravity with respect to a iixed point on the container and substantially independently of liquid level in the container, visible indicating means connected with the cartridge and movable therewith, means connected with the container exposing said visible means for inspection, iiexible conduit means connecting said inlets, the cartridge and the container having a relatively limited space therebetween in which filtered oil is located for reducing vibratory cartridge movement with respect to the container.

19. A lter unit comprising a fluid-holding container having inlet and outlet openings, a movable ltering member in the container and immersed in said uid and having inlet and outlet openings, a flexible connection between one or the container openings and one of the iltering-member openings whereby a flow may be etIected serially through the container and iilter- A ing member, resilient means supporting the said movable filtering member against the force of gravity in substantial equilibrium according to its weight and the weight ot its contents and from a point fixed with respect to the container, and means operated as a result oi' the displacement of the filtering member i'or indicating its weight-changed positions with respect to said fixed point.

CYRIL G. SCHELLY.

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