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Publication numberUS3348689 A
Publication typeGrant
Publication dateOct 24, 1967
Filing dateJun 29, 1965
Priority dateJun 29, 1965
Publication numberUS 3348689 A, US 3348689A, US-A-3348689, US3348689 A, US3348689A
InventorsJr Frederick Kraissl
Original AssigneeJr Frederick Kraissl
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Concentric filter elements having assembling and locking means
US 3348689 A
Abstract  available in
Previous page
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Claims  available in
Description  (OCR text may contain errors)


Oct. 24, 1967 F. KRAISSL, JR


United States Patent Ofifice 3,348,89 Patented Oct. 24, 1967 3,348,689 CON CENTRIC FILTER ELEMENTS HAVING ASSEMBLING AND LOCKING IVIEANS Frederick Kraissl, Jr., 244 Kinderkamack Road, North Hackensack, NJ. 07661 Filed June 29, 1965, Ser. No. 467,872 16 Claims. (Cl. 210-238) ABSTRACT OF THE DISCLOSURE Multiple concentric filter elements, an inner element having a handle with a horizontal latch extending radially outwardly therefrom and a plate-type spring extending downwardly and outwardly therefrom, an outer filter element having an upstanding open-ended keeper extending upwardly therefrom, one of said keeper and spring having a pin thereon and the other having a hole therein, so that upon relative rotation of said elements with said spring depressed, the latch enters the keeper to secure the elements together and the pin enters the hole upon release of the spring to lock the elements together.

The present invention is directed to multi-element filterseparators for removing foreign matter from fluids and more particularly to structures wherein two or more filters are nested together and held in a suitable casing.

In my copending application Serial No. 395,157, filed September 9, 1964 and entitled, Fluid Filter Strainer or Separator, I have described an arrangement wherein an outer filter is provided at its upper end with one element of a latch, and an inner filter is provided with the cooperating element whereby, when the filters are nested and are twisted relatively to each other, the latch elements hold the two filters together so that they may be handled as a unit. Such arrangement has been found to be quite satisfactory in practice. However, under some operating conditions, particularly where severe vibration is encountered, the elements of the latch may disengage and the filters may become separated. It also occurs at times that the operator, through carelessness or oversight maynot engage the latch elements completely or firmly, in which case the filters may become loosened from each other.

The present invention is intended and adapted to overcome the deficiencies in prior devices of the above type, it being among the objects of the invention to improve the structures of such devices so as to eliminate the possibility of accidental separation of nested filters.

It is also among the objects to provide a relatively simple device, easy to install, which is strong and reliable, and which results in a positive locking together of said filters and, at the same time, the device is readily accessible for separating the filters for cleaning, repair or replacement.

In practicing the invention, there is provided on the inner of said filters a laterally extending tongue having means for interlocking with a cooperating element on the outer filter. The latter has an upstanding projection with which is associated a slot, opening or shoulder which cooperates with an additional element. The latter may be a pin carried by a spring, which is biased so that when the filters are nested and the tension on the spring is released, the pinwill enter a keeper and positively lock the filters in position. To separate the filters, the spring is again placed under tension to draw the pin from the keeper, whereby the inner filter may be separated from the outer filter.

The invention is more fully described in connection with the accompanying drawings constituting a part hereof, in which like reference characters indicate like parts, and in which FIG. 1 is an exploded view of one form of the invention;

FIG. 2 is a top plan view thereof;

FIG. 3 is a fragmentary view along line 33 of FIG. 2;

FIG. 4 is a similar view showing the locked position;

FIG. 5 is a perspective view of a modified form;

FIG. 6 is a top plan view of the embodiment of FIG. 5;

FIGS. 7, 8 and 9 are enlarged, fragmentary views showing certain details of the construction;

FIG. 10 is an exploded view of a three-filter arrangement;

FIG. 11 is a top plan view of the assembled structure shown in FIG. 10;

FIGS. 12 and 13 are enlarged fragmentary views illustrating details of the structure of FIG. 10; and

FIG. 14 is a cross-sectional view taken along line 1414 of FIG. 13.

Referring to FIGS. 1-4, there is provided an outer filter 1 having a rim 2 having upstanding projections constituting opposed latches 3 and 4. An opening or hole 5 is formed in latch 3. Spaces 6 and 7 constitute slots forming latches. Inner filter 8 has a lower rim 9 of a diameter to fit into filter 1 at the bottom 10 thereof. An arcuate handle 11 is secured to the top of filter 8 and has a lateral tongue 12 adapted to enter slot 7. An opposite tongue 13 has notch 14 adapted to fit into slot 6.'Spring 15 of angular shape has a laterally extending pin 16.

In the nesting of filters 1 and 8, spring 15 is compressed, filter 8 is lowered into filter 1 until the tongues rest on rim 2. Filter 8 is then rotated until tongues 12 and 13 have been seated in Slots 7 and 6 respectively. The spring 15 is released causing pin 16 to enter hole 5. The filters are thus securely locked against accidental displacement.

In FIGS. 59 there is shown a modified form of locking arrangement in which there are two locks and the locks do not fit into holes but are held against shoulders on or notches in said projections. Handle 11 has on one side spring 15 and pin 16, and projection 4 has shoulder 5' instead of hole 5 against which pin 16 is held. Opposite spring 15 is spring 20 having a lateral flange 20'. Tongue 22 as well as tongue 13, has notch 23 to interfit in slots 6 and 7. Flange 20' abuts against shoulder 24 of projection 5.

To assemble the unit, springs 15 and 20 are grasped between the thumb and fingers and are compressed. Filter 8 is inserted into filter 1, is rotated clockwise until the latches are in place, and then the springs are released. They rest against shoulders 5' and 24 respectively.

FIGS. 1014 illustrate an embodiment in which three filters are interlocked into a single unit. Outer filter 1 has the same structure as above. Inner filter 8 has lateral tongues 12 and 13 with notches 25 to fit into slots 7 and 6. It also has springs 26 having extensions or pins 26'. Springs 26 have their bases 27 secured to the sides of rim 28 at the upper end of filter 8. Projections 7 and 6 are provided with holes 29 and 30 into which pins 26' enter to lock filters 1 and 8 together.

A central filter 31 fits into inner filter 8. It has an upper rim 32 onto which handle 11 is secured. Said handle has a pair of second tongues 33 and 34 in opposed relation and extending horizontally outward. The tongues have notches 35 and 36 which are adapted to fit into filter 8. The sides of handle 11 have springs 37 and 38 with extensions or pins 39 and 40. Filter 8 has second projections 4' and 5 forming slots similar to slots 6 and 7, and openings 41 and 42 are formed in said second projections.

The assembly is made by grasping springs 26 and compressing them. Filter 8 is lowered into filter 1, is twisted clockwise to firmly seat tongues 12 and 13 in projections 4 and 5, after which the springs are released so that pins 26 enter openings 29 and 30. Then springs 37 and 38 are compressed, filter 31 is lowered into filter 8, filter 31 is twisted clockwise to seat second tongues 33 and 34 in the slots of second projections 4' and Then second springs 37 and 38 are released so that pins 39 and 40 enter openings 41 and 42. All three filters are locked together and handle 11 serves as means for inserting the unit into filter casing (not shown).

Although the invention has been described by the use of several specific embodiments, the invention is not limited to such embodiments as they have been described to illustrate the nature of the invention but not to limit its scope. Many changes may be made in the details of the construction. For instance, the several springs need not be compression springs but they may be extension springs which bias radially inward to provide the locks. The springs need not be fiat but may be in other forms such as spring rods or wires or coils. The openings in the projections need not be holes but they may be slots of appropriate size and shape.

The filter elements are shown as being cylindrical, but they may vary, it being important that they nest together and are capable of rotation to lock them together. As another variation, a filter may be inserted into an outer filter until they nest, and without twisting, cause the pins to enter the keepers to lock the parts together. In some instances, the handle may be dispensed with and the movement of nesting filters may be performed by grasping the body of the filter with the hand.

These and other changes may be made within the spirit of the invention, which is to be broadly construed, and not to be limited except by the character of the claims appended hereto.

What is claimed is:

1. In a multi-element filterseparator comprising an outer substantially cylindrical filter and an inner concentric filter, an arcuate handle of inverted U-shape having its lower end secured to the inner filter, and cooperating means on said handle and said outer filter for latching said filters together, the improvement which comprises a tongue latch at the lower end of said handle extending laterally outward from said inner filter, a horizontal flange extending outwardly from the upper end of said outer filter, an upstanding projection on said outer filter, a horizontal slot in one of said tongue and projection, said projection extending above said flange and being secured to said outer filter, said tongue fitting into said projection on relative rotation of said filters, a spring having an attachment to an intermediate part of said handle and extending downwardly, an opening in one of said projection and spring, the lower end of said spring being adjacent to and in line with said projection, and cooperating means on the other of said projection and spring for entry into said opening, said opening and said cooperating means being in horizontal alignment when said tongue is in latched position in said slot.

2. A filter-separator according to claim 1 in which said spring is biased toward said projection.

3. A filter-separator according to claim 1 in which there are present springs on opposite sides of said handle and latches on opposite sides of said outer filter.

4. A filter-separator according to claim 1 in which said spring is a fiat plate.

5. A filter-separator according to claim 1 in which said opening is in said spring and said entry means is on said projection.

6. A filter-separator according to claim 1 which said entry means is an outstanding pin.

7. A filter-separator according to claim 1 in which said tongue extends from said handle.

8. A filter-separator according to claim 1 in which a central filter is concentric with and within said inner filter, a second tongue extending laterally from said central filter, an upstanding second projection on said inner filter, a slot in one of said second tongue and projection, said second tongue fitting into said second projection.

9. A filter-separator according to claim 8 in which there is a spring on said central filter and cooperating pin and hole on said spring and second projection to interfit when said tongue is in latched position.

10. A filter-separator according to claim 8 in which there are at least two sets of said second tongue and second projection spaced from the first set.

11. A filter-separator according to claim 8 in which there are at least two sets of said second tongue and second projection spaced in substantially diametrically opposed relation to the first set.

12. A filter-separator according to claim 1 in which said tongue has a notch at one edge, said notch fitting into said slot when said tongue is in latched position.

13. In a multi-element filter-separator in which a plurality of concentric inner and outer filters are in concentric arrangement and means for latching said filters together, the improvement which comprises a fiat substantially horizontal latch extending radially outward from said inner filter and along the top of said outer filter, an upstanding keeper on said top and having an open-ended slot for reception of said latch, a flat spring attached to said inner filter extending downward and outward, a radial projection on one of said keeper and the lower end of said spring, a complementary opening in the other of said keeper and spring, said spring being compressible inwardly to permit said latch and keeper to pass into latching position and upon release of said spring to allow said projection to enter said opening, whereby accidental unlatching thereof is prevented.

14. In a multi-element filter-separator according to claim 13 in which there is a pin on one of said spring and by-pass said latching means during latching movement, a notch at the lateral edge of said horizontal latch, said notch adapted to embrace said keeper at the inner edge of said slot.

15. In a multi-element filter-separator according to claim 13 in which there is a pin on one of said spring and keeper, and a hole in the other of said spring and keeper to interlock.

16. In a multi-element filter-separator according to claim 13 in which there is a second set of spring and keeper on the side of said multi-element opposite said first set.

References Cited UNITED STATES PATENTS 753,984 10/1903 King 210--473 X 1,115,379 10/1914 Bessent 2l0238 X 1,169,826 2/1916 Horan 2l0479 X 1,348,536 8/1920 Billings et al 2l0452 2,534,286 12/1950 Maitzen 2l0237 2,761,565 9/1956 Hutchinson 2l0479 X 2,792,118 5/1957 Kraissl 210-315 X 3,179,253 4/1965 McNeal 2l0315 3,211,535 10/1965 Hirahara 2l0479 X REUBEN FRIEDMAN, Primary Examiner.

P. SPEAR, Assistant Examiner,

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Referenced by
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US4138337 *Nov 17, 1977Feb 6, 1979Smith Robert GFilter cartridge
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CN103657218A *Sep 22, 2012Mar 26, 2014马英Method for fixing screen drum of residue-slurry separator
U.S. Classification210/238, 210/315, 210/342
International ClassificationB01D29/00
Cooperative ClassificationB01D29/0013, B01D29/0043, B01D29/58, B01D2201/4015
European ClassificationB01D29/58, B01D29/00A10L, B01D29/00A2