Tension clamp and screen system

Information

  • Patent Grant
  • 6179128
  • Patent Number
    6,179,128
  • Date Filed
    Friday, October 2, 1998
    26 years ago
  • Date Issued
    Tuesday, January 30, 2001
    23 years ago
Abstract
A clamp system has been invented for releasably securing a screen to a vibratory screen apparatus, the clamp system in one aspect having a front plate for abutting a portion of a vibratory screen apparatus, a first link movably connected to the front plate and having a first contact surface, a second link movably connected to the first link and having a second contact surface, a bolt with a first end projecting out beyond the second link and a second end projecting out beyond the front plate, the bolt tightenable in place by an adjusting nut on one end thereof, and the first link and the second link movable so that the first contact surface abuts the second contact surface and the links are then held releasably together. In one aspect the front plate and the first link are movably mounted together by two plate pinions, one on each side of two spaced-apart sides of the front plate; the second link and bolt stop member are movably mounted together by two swivel pinions, one on each of two spaced-apart sides of the second link; and first link and the second link are movably mounted together by two link pinions one on each of two spaced-apart sides of the links, and these link pinions are positioned so that when the first contact surface and the second contact surface are in abutting contact centers of the link pinions are below a line between centers of the plate pinions and centers of the swivel pinions. Methods have been invented for using such clamp systems and vibratory screen apparatus have been invented with one or more such clamp systems.
Description




BACKGROUND OF THE INVENTION




1. Field of the Invention




This invention is directed to tension clamping devices for screens mounted on vibratory screening system; to systems with such devices; and to methods of their use.




2. Description of Related Art




The prior art discloses a variety of devices and apparatuses for securing a screen to a vibratory screening apparatus. Many of the prior art systems employ a simple bolt, nut, and plate combination, with or without shock absorbing material. Tightening and loosening of the nut provides tension adjustment. Exemplary prior art patents include, but are not limited to, U.S. Pat. Nos. 4,303,509; 5,332,101; and 5,392,925.




U.S. Pat. No. 5,332,101 discloses a screen tensioning structure that includes body members with a cam arrangement whose movement creates a pulling effect when cam followers slide up camtracks. Certain commercially available embodiments require a special wrench to turn a movable adjustment nut. Often, the nut can only be effectively adjusted when the structure is in an unlocked position. With some prior art devices sliding surfaces must be lubricated regularly, otherwise the surfaces gall making high torque necessary, which in turn requires a high wrench load which can result in a bent tension bolt.




Certain prior art devices can result in insufficient tension on a screen when their springs collapse (take a set) reducing the total tension load produced by the spring. Many times the only way to then achieve proper tension on a screen is to collapse the spring completely and torque the spring adjusting nut.




There has long been a need for an efficient and effective screen tensioning clamp apparatus. There has long been a need for such an apparatus that can be used with existing vibratory system screen mounts without requiring changes and alternations to the vibratory system. There has long been a need for such an apparatus which is adjustable while in a locked position. There has long been a need for such an apparatus that reduces misalignment between the apparatus and structural members of the vibratory system.




SUMMARY OF THE PRESENT INVENTION




The present invention, in certain embodiments, is a screen tension clamping apparatus that has dual locking links rotatably connected to each other that selectively cam “past center” or “over center” to provide a stable locked mode for the apparatus. A front grip plate is rotatably mounted, in these embodiments, to a first locking link. The grip plate is releasably securable to a typical side mount on a vibratory screen system. The second locking link has, in one aspect, a swivel rotatably mounted to it and a portion of a bolt extends through the swivel, both links, and the front grip plate. A further portion of the bolt extends through the side mount and projects beyond a screen tension rail or screen mounting member. An end of the bolt abuts the tension rail so that tightening the nut at the bolts other end increases tension on the screen. Such tightening can be done after the dual locking links are moved to contact each other in a locked (yet releasable) position.




Typical wrench flats, bosses, or recesses are provided on each of the locking links, in certain embodiments so that off-the-shelf wrenches may be used to move the links apart and together. To provide spring tension on the bolt, a spring or springs may be used between the nut and the swivel; between the grip plate and an enlarged bolt portion; or at any suitable location int he apparatus. In one aspect, spring discs (e.g. one, two, three, four, or more) are used between the nut and the swivel. Such spring discs or flange belleville springs are commercially available.




The swivel permits the links to align with the bolt to reduce or eliminate binding of the grip plate with the side mount of a vibratory screen apparatus.




Certain screens with integral tension rails or side members can also be secured with an apparatus according to the present invention.




The present invention, in certain aspects, provides a vibratory screen apparatus which includes; a basket for mounting of one or more screens; one or more screens releasably mounted to the basket with any tension clamping devices described above or herein; and one or more vibratory devices for vibrating the basket and/or screen.




What follows are some of, but not all, the objects of this invention. In addition to the specific objects stated below for at least certain preferred embodiments of the invention, other objects and purposes will be readily apparent to one of skill in this art who has the benefit of this invention's teachings and disclosures. It is, therefore, an object of at least certain preferred embodiments of the present invention to provide new, useful, unique, efficient, nonobvious screen tension clamping apparatuses, vibratory screen systems with such apparatuses, and methods of their use.




Certain embodiments of this invention are not limited to any particular individual feature disclosed here, but include combinations of them distinguished from the prior art in their structures and functions. Features of the invention have been broadly described so that the detailed descriptions that follow may be better understood, and in order that the contributions of this invention to the arts may be better appreciated. There are, of course, additional aspects of the invention described below and which may be included in the subject matter of the claims to this invention. Those skilled in the art who have the benefit of this invention, its teachings, and suggestions will appreciate that the conceptions of this disclosure may be used as a creative basis for designing other structures, methods and systems for carrying out and practicing the present invention. The claims of this invention are to be read to include any legally equivalent devices or methods which do not depart from the spirit and scope of the present invention.




The present invention recognizes and addresses the previously-mentioned problems and long-felt needs and provides a solution to those problems and a satisfactory meeting of those needs in its various possible embodiments and equivalents thereof. To one skilled in this art who has the benefits of this invention's realizations, teachings, disclosures, and suggestions, other purposes and advantages will be appreciated from the following description of preferred embodiments, given for the purpose of disclosure, when taken in conjunction with the accompanying drawings. The detail in these descriptions is not intended to thwart this patent's object to claim this invention no matter how others may later disguise it by variations in form or additions of further improvements.











DESCRIPTION OF THE DRAWINGS




A more particular description of embodiments of the invention briefly summarized above may be had by references to the embodiments which are shown in the drawings which form a part of this specification. These drawings illustrate certain preferred embodiments and are not to be used to improperly limit the scope of the invention which may have other equally effective or legally equivalent embodiments.





FIG. 1A

is a top view of a clamping apparatus according to the present invention.

FIG. 1B

is a side view of the apparatus of FIG.


1


A.

FIG. 1C

is a top view of part of the apparatus of FIG.


1


A.

FIGS. 1D and 1F

are end views of the apparatus of FIG.


1


C.

FIG. 1E

is a bottom view of part of the apparatus of FIG.


1


A.





FIGS. 2A and 2B

show the apparatus of

FIG. 1A

in a collapsed unlocked position.

FIGS. 2C and 2D

show the apparatus of

FIG. 1A

in an extended, closed, locked position.





FIG. 3A

is a side view in cross section of a swivel of the apparatus of FIG.


1


A.

FIG. 3B

is an end view of the swivel of FIG.


3


A.





FIG. 4A

is a side view of a link of the apparatus of FIG.


1


A.

FIG. 4B

is a bottom view of the link of FIG.


4


A.





FIG. 5A

is a side view of a link of the apparatus of FIG.


1


A.

FIG. 5B

is a bottom view and

FIG. 5C

is an end view of the link of FIG.


5


A.





FIG. 6A

is a side view partially in cross-section of a grip plate of the apparatus of FIG.


1


A.

FIG. 6B

is an end view and

FIG. 6C

is a bottom view of the plate of FIG.


6


A.

FIG. 6D

is a partial side view of the plate of FIG.


6


A.





FIG. 7

is a perspective view of a vibratory screen apparatus according to the present invention.





FIG. 8

is a perspective view of a vibratory screen apparatus according to the present invention.





FIG. 9A

is a perspective exploded view of a system according to the present invention.

FIG. 9B

is an enlargement of part of the system of FIG.


9


A.





FIGS. 10A-10E

are view of a system according to the present invention like those of

FIGS. 1A

,


1


B,


6


A,


6


B and


6


D, respectively.











DESCRIPTION OF EMBODIMENTS PREFERRED AT THE TIME OF FILING FOR THIS PATENT




Referring now to

FIGS. 1A-1F

a device


10


according to the present invention has a bolt


60


that extends through a plate


20


, a first link


30


, a second link


40


and a swivel


50


. A nut


66


threadedly mates with threads


69


to releasably hold the bolt


60


in position.




The bolt


60


has a shaft portion


63


that extends movably through a channel


23


in the plate


20


(see FIGS.


6


A-


6


D). On a front side of the plate


20


a raised portion


25


facilitates holding a head of the bolt


60


in a position to more easily engage a tension rail. An O-ring or other sealing member


67


(see

FIG. 1B

) is, optionally, disposed in a recess


23


within the raised portion


25


and seals against portion


62


of the bolt


60


.




An optional cylinder


29


projects from the rear side of the plate


20


and the channel


23


extends all the way through the plate


20


to the rear end of the cylinder


29


. As will be discussed below, the rear side of the cylinder


29


provides a stop against which movement of the swivel


50


is stopped.




Arms


28


and arm


24


releasably encompass a side mount plate


18


(see

FIGS. 2B

,


2


D), and a lip


27


extends releasably down in front of the side mount plate


18


which is secured to the basket side wall of a basket of a vibratory screen device (not shown).




A ridge


21


across the front of the plate


20


is sized, configured and disposed for pivoting against a flat part of the side mount plate


18


. Alternatively, one or more raised portions or bumps on the front of the plate


20


may be used for this purpose, including, but not limited to, two spaced apart nodules one on either side of the raised portion


25


or a series of three or more nodules across the plate. The ridge


21


allows the assembly to align itself with a tension bolt and inhibits binding of the bolt against parts it may contact.




Pinion holes


19


are located on two sides of the plate


20


for pinions


22


extend through the first link


30


and into the holes


10


to movably connect the plate


20


and the first link


30


. A corresponding recess or hole in the side mount plate


18


can accommodate the raised portion


25


. A seal member, e.g. an O-ring, may be used to seal the portion


25


/plate


18


interface. Alternatively the plate


20


is formed integrally of the link


30


. Pinions may be made of any suitable material, including metal, including, but not limited to hardened steel or stainless steel.




The first link


30


as shown in

FIGS. 1A

,


2


A,


4


A and


4


B has arms


36


with holes


34


therethrough for the pinions


22


. A bar


38


extends between and interconnects the arms


36


. A rear side of the bar


38


is movable to abut the arm


24


of the plate


20


, but the bar


38


may be sized and configured so that it can pass above the arm


24


. The bar


38


in the embodiment shown is spaced apart from the cylinder


29


of the plate


20


by the arms


36


so that the bar


38


does not touch the cylinder


29


. Alternatively a recess may be provided in the bar


38


to accommodate the cylinder


20


and the cylinder


29


may be extended further (further than as shown inn

FIGS. 1A

,


2


A) to the rear. Alternatively, the swivel


50


may, in other embodiments, be deleted and replaced with a block or member that does not swivel or pivot. In aspect in which the cylinder


29


is not used, a bolt has more freedom of movement, e.g. for alignment.




A wrench boss


31


projects from one of the arms


36


for use with any typical known commercially available wrench. Alternatively, a hex recess for an Allen wrench or “star” recess for a corresponding type wrench may be used. Also, a simple hole or projecting surface may be provided for engagement manually, by a hook, or by other similar devices. Alternatively, wrench bosses, engagement bosses or bars, and/or wrench recesses can be provided on both arms


36


.




Pinions


32


extend through holes


35


to movably connect the first link


30


to the second link


40


. As discussed below, a rear surface


37


of the bar


38


serves as a stop for a corresponding surface of the second link


40


. With the bolt


60


removed, the first link


30


can rotate about the pinions


22


past a longitudinal axis of the cylinder


29


.




The second link


40


(see

FIGS. 1A

,


2


A,


5


A and


5


B) has two arms


48


with holes


44


therethrough for the pinions


32


. The arms


48


are disposed within the arms


36


of the first link


30


. A bar


47


interconnects and extends between the arms


48


. A front surface


49


of the bar


47


is movable as the arms


48


rotate about the pinions


32


to abut and stop against the rear surface


37


of the first link


30


.




A wrench boss


41


is engageable by a known wrench to move the second link


40


. The wrench boss


41


may be replaced and/or used with any of the alternatives discussed above for the wrench boss


31


of the first link


30


.




Rear arms


45


have holes


46


for pinions


42


that movably connect the swivel


50


to the second link


40


. A cut out portion


41


in the bar


47


provides a space within which part of the swivel


50


, as discussed below, can rotate.





FIGS. 1A

,


1


D,


1


E,


3


A and


3


B show the swivel


50


. The swivel


50


has two arms


51


with holes


56


therethrough for the pinions


42


. A hole


54


in a member


57


accommodates the belt


60


and an inner surface


58


of a recess


17


provides a stop for the nut


66


. Alternatively, depending on the size of the nut


66


and the recess


52


, a rear surface of the member


57


can serve as a stop for the nut


66


. The surface


49


of the second link


40


may be slanted (downwardly from left to right in

FIG. 5B

) to permit full


360


° rotation of the swivel


50


about the pinions


42


but this degree of rotation is not required. In other aspects only that amount of rotation is needed that allows collapse of the device. The hole


54


may have a diameter slightly larger than the outer diameter of the bolt


60


to permit some movement of the bolt


60


with respect to the walls of the hole


54


.




As shown in

FIGS. 2B and 2D

an enlarged bolt end


61


extends through a hole


95


in and engages an inner surface of a tension rail


92


. The enlarged bolt portion


62


abuts an inner surface of a basket sidewall


91


of a screen-holding basket of a vibratory screening apparatus. The lip


27


of the plate


20


engages the side mount plate


18


. A screen


93


is engaged by the tension rail


92


and abuts a stop


94


secured to or formed integrally of the basket sidewall


91


.




As shown in

FIGS. 2A and 2B

, the apparatus


10


is in a collapsed open position and the screen


93


has not been completely tensioned by the combination of the apparatus


10


and the parts of the vibratory screening apparatus. The enlarged end


61


of the bolt


60


has been inserted through the hole


95


but the bolt


60


has not been turned to prevent the bolt end


61


from exiting the hole


95


(to the right in FIG.


2


B). A shaft portion


68


of the bolt


60


is in the hole


45


. The links


30


and


40


are in the open collapsed position. Arrows on the links in

FIG. 2A

indicate how the links will be moved to go to the closed extended position of

FIGS. 2C and 2D

. The bolt


66


has not been tightened against the swivel


50


in

FIGS. 2A and 2B

.




As shown in

FIGS. 2C and 2D

, the end


61


of the bolt


60


has been turned 90 degrees, releasably holding the bolt end against an inner surface of the tension rail


92


. The links


30


and


40


have been moved to a closed extended position and the nut


66


has been tightened (rotated and moved to the left as viewed in FIG.


2


D). The screen


93


has been pulled against the stop


94


and the top of the tension rail


92


has moved to abut the inner surface of the basket sidewall


91


.




As shown in

FIG. 2D

, the pinions


32


are disposed below a line L between the pinions


22


and


42


and the surface


49


of the bar


47


of the second link


40


has stopped against the surface


37


of the bar


38


of the first link


30


. Due to the “below center” position of the pinions


32


, the links


30


,


40


are releasably locked together. By using appropriate wrenches on the bosses


31


,


41


, the links may be selectively moved apart to selectively unlock them, permitting release of the screen


93


from the basket.




The size and configuration of the bolt


60


, in combination with the springs


64


and the nut


66


, permit adjustment of tension on the screen


93


after the links


30


,


40


are moved to the closed extended position of

FIGS. 2C

,


2


D. Alternatively, the pinions may be located and the stop surfaces of the links located so that the links meet “above center” for easier opening of the links.





FIG. 7

shows a vibratory separator system


110


with a plurality of apparatuses


10


according to the present invention releasably securing screens S and T within a basket B. One such a vibratory separator apparatus (with different screen securement apparatus) is disclosed in U.S. Pat. No. 4,735,712 incorporated fully herein for all purposes.





FIG. 8

shows a vibratory separator system


120


with a plurality of apparatuses


10


according to the present invention releasably securing screens V within a basket C. One such a vibratory separator apparatus (with different screen securement apparatus) is disclosed in U.S. Pat. No. 4,882,054 incorporated fully herein for all purposes.





FIG. 9A

shows a system


200


according to the present invention with two screen baskets


202


,


204


; vibrator apparatus


206


,


208


; heater beds


210


,


212


(one under each basket); heat transfer plates


214


; heated fluid supply line


220


; and fluid return line


222


. A plurality of clamp assemblies


10


according to the present inventions hold a screen or screens (not shown) in the baskets


202


,


204


. (Clamps


10


shown in place on top basket; clamps


10


connectible to, but not shown on, lower basket.) The lines


220


and


222


are connected to and in fluid communication with a heated fluid generating system, e.g. a steam boiler system G. Steam flows in a line


220


to a heat exchange bed


210


. Cooled fluid is returned via the line


222


which flows to a condenser CN and is pumped by a pump P back to the system G. The bed


212


may have its own system G or it may be in fluid communication with the system G. Similarly the heat transfer plates


214


have their own system SY with supply line L and return line M, but the heat transfer plates may be tied into the system G. In one aspect the system G raises the temperature of fluid (e.g. mud) introduced to the system


200


up to at least 70° F.; in another aspect, to at least 80° F., and in a particular aspect to 90° F. or higher. Any suitable heat exchange system may be used instead of the system G.





FIGS. 10A-10E

show an alternative embodiment


300


of the system


10


and like numerals indicate the same parts. The cylinder


29


of the system


10


is deleted and an area


302


for an O-ring


67


is larger than the recess


23


of the system


10


. A ridge


304


encircles the area


302


. A washer


306


is used with a nut


366


.




In conclusion, therefore, it is seen that the present invention and the embodiments disclosed herein and those covered by the appended claims are well adapted to carry out the objectives and obtain the ends set forth. Certain changes can be made in the subject matter without departing from the spirit and the scope of this invention. It is realized that changes are possible within the scope of this invention and it is further intended that each element or step recited in any of the following claims is to be understood as referring to all equivalent elements or steps. The following claims are intended to cover the invention as broadly as legally possible in whatever form it may be utilized. The invention claimed herein is new and novel in accordance with 35 U.S.C. § 102 and satisfies the conditions for patentability in § 102. The invention claimed herein is not obvious in accordance with 35 U.S.C. § 103 and satisfies the conditions for patentability in § 103. This specification and the claims that follow are in accordance with all of the requirements of 35 U.S.C. § 112. The inventor may rely on the Doctrine of Equivalents to determine and assess the scope of their invention and of the claims that follow as they may pertain to apparatus not materially departing from, but outside of, the literal scope of the invention as set forth in the following claims.



Claims
  • 1. A screening system comprisinga screen mounting basket, at least one screen mounted to the basket, at least one clamp system clamping the at least one screen to the screen mounting basket, the at least one clamp system comprising a front plate for abutting a portion of a vibratory screen apparatus, a first link movably connected to the front plate and having a first contact surface, a second link movably connected to the first link and having a second contact surface, a bolt with a first end projecting out beyond the second link and a second end projecting out beyond the front plate, the bolt tightenable in place by an adjusting nut on one end thereof, and the first link and the second link movable so that the first contact surface abuts the second contact surface and the links are then held releasably together, the front plate and the first link movably mounted together by two plate pinions, one on each side of two spaced-apart sides of the front plate, the second link and bolt stop member movably mounted together by two swivel pinions, one on each of two spaced-apart sides of the second link, and first link and the second link movably mounted together by two link pinions one on each of two spaced-apart sides of the links, said link pinions positioned so that when the first contact surface and the second contact surface are in abutting contact centers of the said link pinions are below a line between centers of the plate pinions and centers of the swivel pinions.
  • 2. The vibratory screen system of claim 1 wherein the at least one clamp system is a plurality of spaced-apart clamp systems each releasably mounting the at least one screen to the screen mounting basket.
  • 3. The vibratory screen system of claim 1 wherein the at least one screen is a plurality of spaced-apart screens.
  • 4. The vibratory screen system of claim 3 wherein a first screen of the plurality of screens is above a second screen of the plurality of screens.
  • 5. The screening system of claim 1 further comprisingvibrator apparatus connected to the screen mounting basket.
  • 6. The screening system of claim 1 further comprisingheating apparatus for heating the at least one screen.
  • 7. The screening system of claim 1 wherein the first end of the bolt of the at least one clamp system has a threaded portion and the at least one clamp system further comprisingthe adjusting nut for threadedly engaging the threaded portion of the first end of the bolt, and a bolt stop member mountable between the adjusting nut and the second link and having a channel therethrough through which the bolt extends.
  • 8. The screening system of claim 7 wherein the bolt stop member is movably mounted to the second link.
  • 9. The screening system of claim 7 wherein the at least one clamp system further comprises spring means between the adjusting nut and the bolt stop member.
  • 10. The screening system of claim 9 wherein the spring means further comprises at least one disc spring around the bolt and disposed between the adjusting nut and the bolt stop member.
  • 11. The screening system of claim 1 wherein the bolt of the at least one clamp system has an enlarged portion for sealingly abutting a front exterior surface of the front plate and the at least one clamp system further comprisinga seal member between the enlarged portion of the bolt and the front exterior surface of the front plate.
  • 12. The screening system of claim 1 wherein the at least one clamp system further comprises manipulation means on at least one of the links for facilitating releasing of the links from contacting each other.
  • 13. The screening system of claim 12 wherein the manipulation means includes sub-means on each link.
  • 14. The screening system of claim 12 wherein the manipulation means comprises first wrench structure on the first link, and second wrench structure on the second link.
  • 15. The screening system of claim 14 wherein the first wrench structure and the second wrench structure is each a hexagonal operating boss projecting outwardly from its respective link and secured to or formed integrally of its respective link.
  • 16. The screening system of claim 8 wherein the bolt stop member is rotatable through 360°.
  • 17. The screening system of claim 1 wherein the front plate of the at least one clamp system has a ridge projecting out from a front surface of the front grip plate, the ridge sized and configured for contacting a side mount plate of a vibratory screening apparatus.
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Entry
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