WO1980002187A1

WO1980002187A1 - Stationary siphon

Info

Publication number: WO1980002187A1
Application number: PCT/US1980/000329
Authority: WO
Inventors: R Steffero
Original assignee: R Steffero
Priority date: 1979-03-29
Filing date: 1980-03-31
Publication date: 1980-10-16
Also published as: EP0026206A1; JPS56500505A; EP0026206A4

Abstract

A stationary siphon assembly (44) for removing condensate from the floor (54) of a rotating steam-heated dryer (10). The siphon assembly (44) features continuous siphoning at minimum differential pressure, and the ability to maintain full flow even during small angular changes between the intake tube (46) and discharge tube (48) of the siphon assembly (44). The improved assembly comprises a novel pivot (60) that connects the intake tube (46) to the discharge tube (48) and which permits a small variation in angle therebetween with negligible reduction in flow and no loss of condensate back to the dryer. A self-positioning embodiment automatically positions the foot (52) of the intake tube (46) at the vertical center line (28) of the dryer (10), while an adjustable embodiment permits the tip-to-shell clearance (57) to be adjusted externally of the dryer (10) during operation.

Description

STATIONARY SYPHON

BACKGROUND OF THE INVENTION

Field of the Invention

The present invention is related to steam-heated rotary dryers and, more importantly, is directed towards a new and improved stationary siphon assembly for remov¬ ing condensate from the bottom floor of the rotating drum of a steam-heated dryer.

Description of the Prior Art

Steam-heated roll dryers are in wide use in such varied industries as paper, boxboard, textiles, rubber, plastics, and the like. Such dryers operate generally by introducing steam at high pressure into the interior of a rotating drum for drying the industrial product being drawn over the exterior of the drum. The steam introduced into the drum condenses into a liquid which, in turn, must be removed from the drum in order to maintain the desired high temperatures on the outer surface of the drum. It has been known for many years to provide a siphon tube extending through the main external bearing of the drum in order to remove the condensate which generally collects at the bottom of the drum. The early siphon designs, as evidenced by United States Patent 1,919,416, consisted simply of a curved pipe extending through the journal bearing down towards the floor of the drum, the open end of the pipe being generally stationarily positioned at the point where the condensate puddle collected while the drum rotated. It was soon realized that the distance between the open end or tip of the siphon pipe and the shell or floor of the drum was important in maximizing the effi¬ ciency of the condensate removal, since at faster drum speeds, the condensate would be forced against the sides of the dryer with ever increasing pressure, making it more difficult to remove.

Simple curved siphon pipes are still in use today, but suffer from several de iciencies. One deficiency is that, due to their great weight, they tend to sag into the journal, causing the latter to bend the pipe out of alignment. The pipe must then be removed from the dryer, rebent manually, and reinserted into the dryer, which can easily throw off the desired tip-to-shell clearance. Further, in order to remove or insert such a siphon tube, a mechanic must draw or push it through the journal which, in and of itself, can undesirably effect the curvature of the pipe. In addition, the weight of the pipe on the journal has been known to cause a portion of the pipe to break off, thereby requiring replacement. Finally, if the tip of the pipe is cut or positioned improperly, it can seal against the shell of the dryer to prevent condensate from being withdrawn at all. All of these deficiencies severely reduce efficiency by wasting tremendous amounts of heat, time and energy.

The need was therefore recognized to provide a more efficient and precision siphon for rotating steam dryers than would be afforded by a bent iron tube. An early example of an attempt to provide a siphon whose tip-to-shell clearance was adjustable is evident in the United States Patent to Young (1,953,525). However, this structure, as well as others like it, suffer from the^* deficiency of utilizing parts within the roll dryer which are too readily subjected to wear and tear, thereby requiring frequent replacement. Downtime on a rotary dryer in a large mill is extremely expensive, and every effort must be made to maximize durability and, hence, efficiency.

Two types of siphons have emerged as representative of the state of the art. Both types utilize a horizontal discharge tube which extends through the roll journal bearing of the drum, and include an intake tube which is angularly coupled to the discharge tube and extends to the inside surface of the drum. One of the types of siphons may be referred to as a stationary siphon, as evidenced by United States Patent 3,473,237 to McCourt, since the intake tube remains essentially stationarily positioned at the lowermost portion of the roll dryer. The other type of siphon is known as a rotary siphon since the open end of the intake tube rotates with the drum of the dryer, as evidenced by the Asfura et al Patent 3,948,283. Both types of known siphons have their advantages and disadvantages. For example, in a rotary siphon, when the drum stops rotating and the intake tube happens to be positioned at the top of the roll, it is impossible to withdraw any additional condensate from the drum, since the condensate will by gravity then be positioned at the bottom of the drum. Further, if constantly rotating, the tip of the intake tube of a rotary siphon may only be in the condensate puddle for a small portion of the total angular rotation of the siphon, thereby providing a discontinuous siphon flow through the exhaust tube, which can be inefficient by, for example, causing flashing in the siphon tube.

A major cause of failure of known rotary and stationary siphons continues to be mechanical malfunc- tion due to the tremendous amount of vibration and wear experienced during operation. A major element of a siphon assembly which is particularly subjected to mechanical failure is the elbow or hinge between the discharge tube and the intake tube. One design of an elbow in wide use today comprises a simple pin hinge that joins the discharge tube and intake tube. As typified by Figure 2 of the McCourt patent (3,473,237), such structures include a reduced orifice within the tubes for passage of condensate there- through, and a flanged hinge assembly mounted on the outside of the tubes which permits the intake tube to pivot freely with respect to the discharge tube. A major operational difficulty with such an elbow struc¬ ture is that when the intake tube pivots upwardly from its lowermost position, the reduced orifices become unseated, so that the condensate flowing up the intake tube falls back into the drum. Accordingly, at any time when the intake and discharge tubes are unseated with respect to one another, which occurs frequently due to the inherent vibration and irregu¬ larities in the drum roll surface, the siphon is working against itself by returning the condensate to the interior of the drum. McCourt recognized this problem in his patent and attempted to solve it by providing a rod through the discharge tube to fix the angle of the intake tube to prevent the same from becoming unseated from the discharge tube. The problem with this solution has been that some "give" or movement of the intake tube is desirable due to the inherent vibrations, and -since an overly rigid construction will be subject to failure upon encountering an obstruction in the wall of the roll dryer, or the like.

Another difficulty with the prior art hinged elbows is that their restricted or reduced orifices causes a pressure drop which, in -turn, can cause flashing in the elbow which can further restrict the free flow of condensate. It would clearly be desir¬ able if the cause of such flashing in the elbow could be eliminated.

A further rather obvious difficulty with the hinged elbow constructions of the prior art has been that they are relatively brittle and therefore are highly prone to mechanical failure. This is perhaps the most frequent cause of siphon breakdown in rotary dryers, and creates unnecessary and expensive downtime.

It would therefore be clearly desirable if the high mechanical failure rate of the prior art hinged elbows could be eliminated or reduced, the efficiency of the condensate removal increased, flashing eliminated and full flow of condensate maintained at the lowest possible differential pressure.

A still further deficiency of prior art rotary dryers has been an inability to easily and quickly change the temperature on the outer surface of the drum during operation. When working with certain materials, such as rubber, plastics, textiles, and the like, the normal technique is to reduce the steam pressure into the dryer to attempt to lower the steam temperature within the roll which, in turn, lowers the temperature on the surface of the drum. This involves a time-consuming process, since one must simply wait until the surface cools sufficiently as a result of the decreased steam pressure. It would clearly be desirable if it were possible to reduce^' the surface temperature of a rotary dryer without reducing incoming steam pressure and without neces¬ sitating a long wait.

It is towards overcoming these deficiencies and providing these advantages that the present invention is advanced.

In summary, the prior art United States patents in this general area of which I am aware include: 1,919,416; 1,953,525; 2,934,831; 3,473,237; and 3,948,283.

OBJECTS AND SUMMARY OF THE INVENTION

It is therefore a primary object of the present invention to provide a stationary siphon assembly which overcomes all of the disadvantages and defi- ciencies of the prior art structures described above.

Another object of the present invention is to provide a new and improved stationary siphon assembly which is easy to install in existing steam dryers.

A further object of the present invention is to provide a unique stationary siphon assembly which avoids reduced orifices and thereby provides full condensate flow at minimum differential pressure.

A still further object of the present invention is to provide an improved stationary siphon assembly wherein the weight of the siphon is better supported within the roll journal to reduce bounce, vibration and twisting.

An additional object of the present invention is to provide a stationary siphon assembly which provides full flow, continuous siphoning of condensate at any differential pressure even when the intake tube is moving angularly with respect to the discharge tube.

Another major object of the present invention is to provide an improved siphon joint between the intake tube and the discharge tube which permits full flow siphoning at reduced differential pressures over a range of angles between the discharge tube and intake tube, without causing a "short circuit" or recycling of the condensate. *

A still further object of the present invention is to provide a stationary siphon assembly which reduces the chances of flashing occurring inside the siphon tube.

Another object of the present invention is to provide a siphon assembly for a rotating steam dryer which is self-positioning at the optimum location within the drum. A still additional object of the present invention is to provide an adjustable stationary siphon for a rotating steam dryer which permits controlled adjustment of the tip-to-shell clearance from outside the drum during operation for facilitating control of the outside surface temperature of the drum.

The foregoing and other objects are attained in accordance with one aspect of the present invention through the provision of an improvement to a stationary siphon assembly which is axially inserted into a rotary drum that is heated by steam. The drum has at its insertion end a main journal with an axial bore, and the siphon assembly includes a discharge tube - extending through the axial bore and angularly coupled to a downwardly extending intake tube for withdrawing condensate from the floor of the drum and transporting same to the discharge tube for removal. The improvement comprises means adapted to couple one end of the intake tube with one end of the discharge tube for ensuring continuous removal of the conendsate from the drum even during small changes in angle between the intake tube and the discharge tube.

In accordance with more specific aspects of the present invention, the means includes a main housing adapted to be connected to one end of one of the tubes, and knuckle means pivotally mounted to the main housing and adapted to be connected to the other one end of the other tube. The main housing preferably includes an outer concave cylindrical seat adjacent to which the knuckle means is positioned, and a longi¬ tudinal bore opening onto the seat. The inner diameter of the bore is preferably substantially the same as that of the adjoining one end of the tube and includes shoulder means for receiving same.

In accordance with other aspects of the present invention, the knuckle means has a substantially cylindrical outer surface for mating with the concave cylindrical seat of the main housing, and a conduit formed therewithin and defined by a first orifice opening on one portion of the. cylindrical outer sur¬ face and a second orifice opening on another portion of the cylindrical outer surface, the first and second orifices having non-coaxial axes. The diameter of the first orifice is preferably substantially the same as that of the bore in the main housing, while the diameter of the second orifice is substantially the same as the outer diameter of said one end of the intake tube so as to receive same therewithin. The diameter of the conduit is substantially equal to that of the first orifice.

In accordance with yet other aspects of the present invention, the main housing further includes first and^' second side arms extending parallel beyond the seat and having first and second coaxial apertures formed therein, while the knuckle means includes substantially planar end walls having first and second pivot studs extending respectively therefrom and into • the first and second coaxial apertures. Also preferably provided are means for limiting the rotation of the knuckle means with respect to the main housing, which preferably takes the form of pin means projecting outwardly from one of the end waifs of the knuckle means for engaging an edge of one of the side arms of the main housing.

In accordance with still other aspects of the present invention, means may be provided for adjusting the height of the intake tube above the floor of the drum and, in a preferred embodiment, may comprise spring means normally biasing the intake tube away from the drum floor. The height adjusting means may further include means actuable from the outside of the drum for overcoming the bias exerted by the spring means. More specifically, the spring means is coupled between the discharge tube and the intake tube and extends over the means* adapted to couple one end of the intake tube with one end of the discharge tube, while the means actuable from outside the drum comprises cable means attached at one end thereof to the intake tube and extending under the tubes through the bore to terminate in a means for locking same. In accordance with another aspect of the present invention, there is provided apparatus which comprises a rigid housing having an outer concave cylindrical seat and a first conduit having a first opening on one end of the housing and extending through the housing to a second opening on the seat. The apparatus further includes a rigid substantially cylindrical member pivotally coupled to the.housing and having an outer cylindrical surface a portion of which is adjacent the seat and having a second conduit formed therein with a third opening on one portion of the surface and a fourth opening on another portion of the surface. The first and second conduits are of substantially the same diameter, and the first and fourth openings define first and fourth axes, respectively, which are non-coaxial when the second opening is coaxially aligned with the third opening.

BRIEF DESCRIPTION OF THE DRAWINGS Various objects, features and attendant advantages of the present invention will be more fully appreciated as the same becomes better understood from the follow¬ ing detailed description of the present invention when considered in "connection with the accompanying drawings, in which: Figure 1 is a side-sectional view, partially fragmented, which illustrates a preferred embodiment of the stationary siphon apparatus of the present invention;

Figure 2 is a sectional view of the apparatus illustrated in Figure 1 and taken along line 2-2 thereof;

Figure 3 is an enlarged, side-sectional view of the improved joint of the present .invention;

Figure 4 is a top-sectional view of the improved joint of Figure 3 and taken along line 4-4 thereof;

Figure 5 is a side view of the improved joint of the present invention in another operative position; and

Figure 6 is a sectional view similar to Figure 3 but illustrating the structure thereof in another operative position.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring now to the drawings, wherein like reference numerals represent identical or- corresponding parts throughout the several views, and more particu¬ larly to Figure 1 thereof, reference numeral 10 indicates generally a rotatably mounted, steam-heated drum or roll dryer. Roll dryer 10 includes a cylindrical wall 12 over which the material t be dried is passed. The wall 12 is heated by steam introduced to the interior of the dryer 10 via steam conduit 20. Steam conduit 20 is formed by a roll journal 18 which extends from a standard journal hub 16 formed in an end wall 14 of the dryer 10.

The steam is introduced and the condensate is withdrawn from the roll dryer 10 by means of a substan¬ tially conventional steam rotary joint or union which is indicated generally by reference numeral 30. The union 30 may be modified slightly in accordance with an alternate embodiment of the present invention, as will be described in greater detail hereinafter. However, the conventional parts of the union 30 include a head 32 having an inlet 34 for steam and an outlet 36 for the siphoned condensate. The condensate from outlet 36 is fed to a suitable reservoir (not shown) . The joint 30 further includes a body or housing 38 which conventionally includes a seal 40 and a carbon guide 42 for supporting a quick-release nipple 26 therewithin. The same is coupled to the journal hub 16 via a journal flange 22 and a mating flange 24.

The elements described thus far are standard and conventional, and their construction is well-known in the art, and form no part of the present invention. The stationary siphon of the present invention is indicated generally in Figure 1 by reference numeral 44 and includes an intake tube 46 which is angularly coupled to and extends downwardly from a discharge tube 48. The intake tube 46 includes a lower free end or tip 50 which terminates in a pick-up foot indicated generally by reference numeral 52, the structure of which will be described in greater detail hereinafter. The purpose of pick-up foot 52 is to define a proper tip-to-shell distance between end 50 of intake tube 46 and the shell 54 of cylindrical wall 12 where the condensate collects. A preferred distance is, ^'for example, 0.15875 cm. The pick-up foot 52 is preferably positioned along the vertical center line 28 of the dryer 10, a position which may. be predetermined by judicious selection of the length of tubes 46 and 48, as well as the angle therebetween, taking into account the length and diameter of dryer 10. Referring briefly to Figure 2, there is illustrated an end view of a preferred embodiment of the pick-up foot 52 which may comprise a pair of substantially cylindrical quarter-section pipes 51 and 53 which are preferably constructed of stainless steel. The pipe sections 51 and 53 are pivotally coupled to the end 50 of pipe 46 by means of a pivot pin 55 to permit same to become aligned coaxially with pipe 46 during insertion and removal from the roll dryer 10. The height of space 57 between pipe sections 51 and 53 and end 50 of intake tube 46 defines the tip-to-shell clearance of the siphon when the intake tube 46 is in its full down position. The preferred tip-to-shell clearance is, as stated above, preferably 0.15875 cm. Referring back to Figure 1, the other end 56 of the intake tube 46 is joined to one end 58 of the discharge tube 48 by means of a novel pivotable elbow or joint of the present invention which is indicated generally by reference numeral 60 and will be described in greater detail hereinafter. The other end 62 of discharge tube 48 serves as a discharge orifice for the condensate and delivers same to outlet 36 of union 30. A support spider is indicated by reference numeral 61 and comprises three legs which are equi- angularly spaced about discharge tube 48 within roll journal 18 and include brass bearings 63 for riding and supporting the tube 48.

Referring now to Figures 3 through 5, the joint or elbow 60 of the present invention which joins one end 56 of the intake tube 46 with one end 58 of the discharge tube 48 is illustrated in greater detail. The elbow 60 comprises a rigid main housing 64 which includes top and bottom walls 65 and 67 which are joined by side walls 69 and 71. The main housing 64 includes a substantially cylindrical bore 66 extending longitudinally therein. The open end of housing 64 that receives end 58 of pipe 48 preferably includes an increased diameter portion 68 so that the inner diameters of end 58 and bore 66 are substantially equal. The other end of main housing 64 is formed in a concave, substantially cylindrical end surface or seat 70 for mating smoothly with the cylindrical outer surface 72 of a knuckle 74.

The knuckle 74 also includes a pair of parallel, opposed end walls 76 and 78 which have relatively large pivot studs 80 and 82 extending integrally therefrom. The pivot studs 80 and 82 support the knuckle 74 for rotation within a pair of circular apertures 84 and 86, respectively, which are formed _{n a} pair of support arms 88 and 90. Arms 88 and 90 may be secured to the side walls 69 and 71 of housing 64 by means of, for example, screws 92, or may be integral extensions of side walls 69 and 71. The planar abutment of end walls 76 and 78 of knuckle 74 with the inner surfaces of side walls 88 and 90 serves to help prevent side sway of knuckle 74 to keep the motion thereof in a single plane, as will become more clear hereinafter.

Knuckle 74 has a conduit or bore formed therewithin which includes an inlet portion 96 and an outlet portion 98. The entry orifice to«^*inlet portion 96 is formed on the cylindrical outer surface 72 of knuckle 74, as is the exit orifice from outlet portion 98. Although inlet and outlet portions 96 and 98 are indicated in Figure 3 as being substantially cylindrical, they could just as easily be formed of single or dual curved portions, as will become more clear hereinafter. As is also clear from Figure 3, the diameter of the conduit formed by inlet and outlet portions 96 and 98 is preferably substantially equal to the diameter of bore 66 in main housing 64 which is, in turn, preferably substantially equal to the inner diameter of both intake tube 46 and discharge tube 48, in such a manner so as to reduce the instances of discontinuities or restrictions in the condensate flow path. To this end, the inlet portion 96 of the conduit in knuckle 74 may include an increased diameter shoulder 102 for receiving the end 56 of intake tube 46.

In one embodiment of the present invention, which may be referred to as the self-positioning embodiment, a pin 104 (see Figure 5) extends from an end wall, such as end wall 78, of knuckle 74, and is adapted to abut against the lower edge 106 of adjacent arm 90 during clockwise rotation (as viewed in Figure 5) of knuckle 74 so as to define the "rest" angle of knuckle 74 and hence the rest position of intake tube 46 with respect to discharge tube 48. The placement pin 104 may obviously be selected to define any desired rest angle for the self-positioning embodiment. The selection of a particular rest angle will depend, ^' among other things, upon the diameter and length of the roll dryer 10, which in turn define the position of the vertical center line 28 of the dryer, as well as upon the length of pipes 46 and 48. In a model constructed to verify the principles of the present invention, the position of pin 10*4 was selected to define an angle between intake tube 46 and the horizontal of approximately 30 degrees. This, in turn, led to selection of angle 100 (Figure 3) between inlet portion 96 and outlet portion 98 of the conduit within knuckle 74 to be approximately 150 degrees. As stated above, the provision of such an angle 100 is not mandatory, since a curved conduit may be formed in knuckle 74 in lieu of two linear segments. In the case of a curved conduit, it may be appreciated that the angle 100 would be analogous to the angle of intersection between the respective axes of the entry orifice and the exit orifice on surface 72 of knuckle 74.

The structure described thus far includes all elements of the self-positioning embodiment of the present invention. In operation, during insertion of the siphon assembly 44 into roll dryer 10, the pick-up foot 52 is initially adjusted so that its pipe sections 51 and 53 are pivoted to be concentric with the intake tube 46. With tubes 46 and 48 in substantial alignment, the siphon assembly 44 is inserted through the roll journal 18. When the joint 60 clears the end of roll journal 18, the knuckle 74 will rotate clockwise, as viewed in Figure 1, to the extent defined by pin 104. Since the optimum angle will be predetermined for a given dryer, as will the desired extent of insertion of tube 48 through journal 18, automatic placement of the pick-up foot 52 along the vertical center line 28 of the dryer will result. The joint 60 has the unique capability of being

OMPI able to withstand slight angular motion between intake tube 46 and discharge tube 48 while maintaining continuous condensate flow, i.e., without short circuitin any condensate. For example, illustrated in Figure 6 is the joint 60 of Figure 3 in an extreme angular position, i.e., one which is not kikely to occur during operation. Nevertheless, communication between pipe sections 56 and 58 is maintained without causing any condensate flowing therethrough to be redelivered to the inside of the dryer. The joint 60 of the present invention therefore has the ability to conform to or ride the actual surface of the shell or floor 54 of the roll dryer during rotation, and any irregu¬ larities in the surface 54 which cause movement of tube 46 will not affect the continuous flow characteris¬ tics of the siphon of the present invention. While, for the extreme configuration illustrated in Figure 6, the actual flow may be somewhat reduced, the flow will not be interrupted nor will any condensate be redelivered back to the inside of the drum. Since the pick-up foot 52 will be in substantially constant motion (in a vertical plane) during rotation of drum 10, the present invention has the unique ability to continue siphoning even during such motion. Further, in the normal position of the joint 60 illustrated in Figure 3, there are no reduced orifices or restrictions to either decrease flow or create a pressure drop which may cause flashing, as in the prior art joints. Any angular deviations from the normal position of Figure 3 during rotation of the drum are likely to be small, and will only minimally affect the full flow characteristics of the joint 60. Further, the components of the joint 60, being preferably constructed of stainless steel, are highly durable and are designed for years of trouble free operation. It should be understood that the design described thus far as a self-positioning embodiment is not one which encourages up and down movement of the foot 52, but is one which does not prevent such movement from taking place, and does not impede the continuous flow characteristics of the siphon when such movement occurs. For the 30 degree angle described above, a movement of plus or minus 5 degrees, for example, will not affect the continuous flow of condensate. Another unique feature of the stationary siphon of the present invention concerns the fact that, while the weight of the assembly is supported by the pick-up foot 52 riding on the floor 54 of the dryer, the force exerted on the floor 54 is negligible due to the pivotal action of the joint 60. The pick-up foot 52 will therefore not wear at any significant rate, since any sudden shocks will be absorbed by movement of the joint 60. This, in turn, eliminates a major cause. of failure of the rigid siphons of the prior art, and also reduces wear on the foot to a negligible level. These effects are also promoted by constructing the siphon assembly of a softer metal than the floor of the dryer.

Since the pick-up foot is positioned stationarily within the condensate puddle continuously during the dryer rotation, the residual condensate level in the dryer at any given time is reduced. This, in turn, reduces the overall weight of the dryer which, in turn, reduces the drive horsepower required that, in turn, reduces the total energy required. Further, for the intake and exhaust tubes, smaller tubing than normal is preferably employed (e.g., smooth bore number 10 ss tubing) to establish continuous flow and thereby reduce weight. The reduction in weight also reduces wear and tear on the bearings. To remove the siphon assembly 44 from dryer 10, the exhaust tube 48 is withdrawn through journal bearing 18. The intake tube will be rotated to horizont upon contacting the outer edge of bearing 18, and pick-up foot 52 may be rotated to its coaxial position by using, for example, an auxilia5y positioning rod (not shown) .

In certain applications, such as, for example, in drying rubber, plastic, textiles, and the like, a

10 lower temperature is required on surface 12 of dryer 10 than with, for example, boxboard. To lower the temperature in the dryer, the steam pressure is normally reduced in an effort to lower the steam temperature within the roll. As pointed out above, this requires

15 a^' long wait for the surface to cool, and is imprecise. An alternate embodiment of the present invention provides means for increasing the condensate level remaining in the dryer at any given time to thereby decrease the temperature of the surface 12 without

20 reducing the incoming pressure.

This adjustable embodiment employs a spring 10 which is preferably pre-bent at a 15 degree angle so that, in the position illustrated in Figure 1, it is bent an additional 15 degrees for a total of 30 degrees.

^~- The ends of spring 110 are loosely clamped within clamps 112 and 114 secured respectively to intake and exhaust tubes 46 and 48. The ends of spring 110 must be permitted longitudinal movement- within clamps 112 and 114. The pre-bending of the spring is to ensure 0 non-contact . with the joint 60 so as to not impede^" rotation thereof.

Spring 110 biases the intake tube 46 away from the floor 54 of dryer 10. To counteract such bias, a positioning rod or cable 116 extends from a clamp 118 5 positioned on the lower portion of intake tube 46

OMPI WI through guides 120 and 122 and union 30 to terminate in a pull ring 124. The end of the cable 116 adjacent pull ring 124 may be secured through a lock nut 126 which may be manually loosened and tightened to adjust the degree of force counteracting spring 110. That portion of cable 116 in the vicin ty of lock nut 126 may preferably be calibrated in terms of the resulting tip-to-shell clearance of pick-up foot 52.

In operation, if the roll dryer 10 is operating at an undesirably high temperature, the lock nut 126 is loosened, and the cable 116 is allowed to slack a sufficient amount to allow spring 110 to draw pick-up foot 52 upwardly 5 degrees for example. Lock nut 126 is then tightened about cable 116. The increased tip-to-shell distance between pick-up foot 52 and surface 54 permits more condensate to accumulate and thereby cools the outer surface 12 of the roll dryer 10. If a higher temperature is thereafter desired, lock nut 126 is again loosened and the pull ring 124 is pulled outwardly a calibrated distance to lower foot 52 and thereby remove more condensate. The continuous flow characteristics of the joint 60, at its median position and at slight angular variants from the median position, make such adjustability practical, feasible, and efficient without any return of condensate to the interior of the drum.

Obviously, numerous modifications and variations of the present invention are possible in light of the above teachings. For example, the knuckle 74 may be provided with a substantially linear conduit, while the housing 64 may be provided with a curved conduit or non-coaxial conduits. Also clearly, the knuckle portion 74 may be connected to the exhaust tube while the so-called housing portion may be connected to the intake tube. Further, one skilled in the art will recognize that the principles of the present invention may be adapted for use with rotary siphons as well. Therefore, I wish it to be understood that within the scope of the appended claims, the invention may be practiced otherwise than as specifically described herein.

Claims

I CLAIM AS MY INVENTION:

1. Apparatus, which comprises: a rigid housing having a concave cylindrical seat and a first conduit having a first opening on one end of said housing and extending through said housing to a second opening on said seat;_β a rigid substantially cylindrical member pivotally mounted to said housing and having an outer cylindrical surface adjacent said seat and having a second conduit formed therein with a third opening on one portion cf said surface and a fourth opening on another portion of said surface, said firsfand fourth openings defining first and fourth axes, respectively, which are non-coaxial when said second opening is coaxially aligned with said third opening,

2. In a siphon assembly for insertion into a drum to be heated by steam, said assembly including a discharge tube angularly coupled to a downwardly . extending intake tube for withdrawing condensate from the floor of said drum and transporting same to said dis- charge for removal from said drum, the improvement : .: which comprises: means adapted to couple one end of said intake tube with one end of said discharge tube for ensuring substantially continuous removal of said condensate from said drum, said means including a main housing adapted to be connected to_.one of said one ends, and knuckle means pivotally coupled to said main housing and adapted to be connected to the other of said one ends, said main housing having an outer concave cylindrical seat adjacent to which said knuckle means is positioned, said knuckle means having a substantially cylindrical outer surface for mating with said concave cylindrical seat of said main housing.

3. The apparatus as set forth in Claim 2, wherein said knuckle means further includes a conduit formed therewithin and having a first orifice opening on one portion of said outer surface and a second orifice opening on another portion of said outer surface, said first and second orifices having non-coaxial axes.

4. The apparatus as set fofth in Claim 2, wherein said main housing further includes side arm means extending adjacent said knuckle means for pivotally supporting the latter, said knuckle means having substantially planar end walls positioned adjacent said side arm means for preventing lateral movement of said knuckle means in said main housing.

5. In a stationary siphon assembly for axial insertion into a rotary drum to be heated by steam, the drum having at the insertion end a main journal with an axial bore, said assembly including a discharge tube extending through said axial bore and angularly coupled to a downwardly extending intake tube for withdrawing condensate from the floor of said drum and transporting same to said discharge tube for removal from said drum, the improvement which comprises: means adapted to couple one end of said intake tube with one end of said discharge tube for ensuring continuous removal of said condensate from said drum even during small changes in angle between said intake tube and said discharge tube, said means including a main housing adapted to be connected to one of said one ends and knuckle means pivotally mounted to said main housing and adapted to be connected to the other of said one ends, said main housing including an outer concave cylindrical seat adjacent to which said knuckle means is positioned, and a longitudinal bore opening onto said seat, and wherein said knuckle means has a substantially

O. PI cylindrical outer surface for mating with said concave cylindrical seat of said main housing, and a conduit formed therewithin and having a first orifice opening on one portion of said outer surface and a second orifice opening on another portion of said outer surface, said first and second orffices having non-coaxial axes.

6. The improved siphon assembly as set forth in Claim 5, wherein the inner diameter of said bore is substantially the same as that of said one of said one ends and includes shoulder means for receiving same.

7. The improved siphon assembly as set forth in Claim 5, wherein the diameter of said first orifice is substantially the same as that of said bore, while the diameter of said second orifice is substantially the same as the outer diameter of said other of said one ends so as to receive same therewithin.

8. The improved siphσn assembly as set forth in Claim 7, wherein the diameter of said conduit is substantially equal to that of said first orifice.

9. The improved siphon assembly as set forth in Claim 5, wherein said main housing further includes first and second side arms extending parallel beyond said seat and having first and second coaxial apertures formed therein, while said knuckle means includes substantially planar end. walls having first and second pivot studs extending respectively therefrom and into said first and second coaxial apertures.

10. The improved siphon assembly as set forth in Claim 9, further comprising means for limiting the rotation of said knuckle means with respect to said main housing.

11. The improved siphon assembly as set forth in Claim 10, wherein said rotation limiting means comprises pin means projecting outwardly from one of said end walls of said knuckle means for engaging an edge of one of said side arms of said main housing.

12. The improved siphon assembly as set forth in Claim 5, further comprising means for adjusting the height of said intake tube abβve the floor of said drum.

13. The improved siphon assembly as set forth in Claim 12, wherein said height-adjusting means includes spring means for normally biasing said intake tube away from said drum floor.

14. The improved siphon assembly as set forth in Claim 13 wherein said height-adjusting means further includes means actuable from outside said drum for overcoming the bias exerted by said spring means.

15. The improved siphon assembly as set forth in Claim 14, wherein said spring means is coupled between said discharge tube and said intake tube and extends over said means adapted to couple one end of said intake tube with one end of said discharge tube.

16. The improved siphon assembly as set forth in Claim 15, wherein said means actuable from outside said drum comprises cable means attached at one end thereof to said intake tube and extending under said tubes through said bore to terminate in a means for locking same.

17. Apparatus, which comprises: a rigid housing having an outer concave cylindrical seat and a first conduit having a first opening on one end of said housing and extending through said housing to a second opening on said seat; a rigid substantially cylindrical member pivotally coupled to said housing and having an outer cylindrical surface a portion of which is adjacent said seat and having a second conduit formed therein with a third opening on one portion of said surface and a fourth opening on another portion of said surface, said first and second conduits being of substantially the same diameter, said first and fourth openings defining first and fourth axes, respectively, which are non-coaxial when said second ©pening is coaxially aligned with said third opening.