US2114101A - Stuff treatment apparatus - Google Patents

Description

Apru 12, 1938. L T COGHLL 2,114,101

STUFF TREATMENT APPARATUS Filed March 28,'1954 A INVENTOR l c/Zzmes T @fg/LU rlp/MM4- /ATToRNEYs Patented Apr. 12, 1938 UNITED STATES;

STUFF 'FREATMIIEIN'I"v APPARATUS .lames T. Coghill, Hoosick Falls, N. Y., assgnor, by mesne assignments, to The Noble & Wood Machine Co., Hoosick Falla, N.v Y., a corporation of New York Application March 28, 1934, Serial No. 717,719.

2 Claims.

'Ihe present invention relates to an improvement in feed pressure control apparatus for treatment machines wherein the stock is admitted under pressure and passed in fluid form or in a fluid medium, through a treatment zione and there subjected to the desired or necessary forces.

One object among others of my invention, has been to provide apparatus whereb-y the pressure and amount of the material fed to a machine having a constant or regulatable throughput may be automatically controlled and maintained within practical limits of variation.

One embodiment of my invention in a form acceptable for use in connection with the treatment or preparation of paper stock or the like is illustrated in the accompanying drawing attached to and forming a part of the present specification and in which- Figure 1 is a diagram illustrating a form of feed pressure control as appli-ed to a suitable mill or other machine for treating the material; and

Figure 2, a detail in section showing a form, of return control or pressure relief valve adapted for use with the apparatus shown in Figure 1.

For effective operation, apparatus of the kind to which this invention is applicable is preferably supplied by feeding mechanism capable of delivering material for treatm'ent at a substantially constant pressure and adjustableto feed the material at different substantially constant pressures within a suitably wide range. These controls more particularly affect the capacity or rate of throughput of the treatment machines, altho they may also under favorable circumstances be utilized in connection with control over the quality and/or extent of treatment in the machine. So far as the feed pressure is adjustable over a Wide range, the capacity of the treatment machine is widely flexible and capable of satisfying different volume demands; and so far as the controls maintain a given pressure substantially constant, the capacity or throughput remains substantially uniform. In the deiibering, refining, finishing, fibrillation or hydration of wood pulp, for example, these features are especially important, both in actual productio-n and in their relation to economy in plant equipment.

As shown in the drawing, stock is fed to suitable treating apparatus, here shown as a mill A having a feed inlet opening 26 which admits stuit to the feed chamber 23 from a supply chest 20| through a stock supply conduit |5| by means of a suitable pump |52. An outlet conduit 21 discharges treated stock from a discharge chamber 24. A gauge |53 registers pressure in said conduit which includes a T section having one outlet opening toward the mill, or other apparatus, and another toward a return or relief conduit |55 positioned to discharge excess stuff into said chest 20|.

For automaticallyv regulating the feed pressure of the material fed to mill A, a partition or wall across one arm of said T section |60 provides an opening or relief port |6-I, Figure 2, into the stock return conduit |55. In a preferred embodiment, said opening is made in a wall in eifect continuous with the conduit wall and is square in shape. A suitable valve gate |62 movable across said opening is actuated by a piston |63l having a head |64 mounted in cylinder |65. An opening |66 admits uid under pressure into said cylinder at one side of said head and another opening |61 admits uid under pressure at the other side thereof. In the device shown, the valve including gate |62 produces an effective area of the opening |6| which varies as the square of the extent of gate movement, thus adapting the construction for eicient operation when handling both large and small quantities of by-passed stock and for most effectively handling stock varying in conslstency.

To actuate or produce feed controlling movement of said gate- |62, a supply of fluid under pressure is admitted to the cylinder through opening |66 by a pipe |68 and through opening |61 by a pipe |69, the direction of flow or pressure through said pipes being controlled by pilot valve |10 having a Waste vent |1| and a supply inlet pipe |12. The neutral position of the ports in pilot valve |10 is determined by the position of a balance beam |13 pivoted at |14 and having a slidable weight |15. A fulcrum |16 is arranged with one end engaging the underside of beam |13 and the other end resting on the diaphragm' |11 extending across a chamber |18 which is connected by a feeler pipe |19 directly to the feed pressure chamber 23 of mill A. A needle valve admits a suitable supply of water to said feeler pipe |19 from the water main |8| in such volume and at such pressure as to maintain said pipe constantly full of water from said main at substantially all operating pressures in the feed chamber. Thus a moving and constantly renewed head of water in line |19 operates in effect as a flexible link or connecting element through which pressure changes ln the feed chamber are transmitted to the diaphragm |11. Under these circumlstances, the material in the feed chamber is prevented from backing or pushing up into the open end of pipe |19.

In operation, the position of weight |15 along beam |13 will be set to maintain any desired feed pressure in feed chamber 23, indicated for example by a gauge |53. If the feed pressure rises, the increase is transmitted through the water supply in line |19 to diaphragm |11 which moves up and in so doing raises the free end of beam |13. It will be understood that the volume and pressure of water normally supplied in said line |19 are such that no material passes into said line from feed chamber 23, thus preventing clogging in said line by paper pulp or other stuif in said feed chamber. A link or stem |83 connects said beam with the moving part of pilot valve |18 so that when beam |13 moves upwardly supply water under pressure is admitted through a port of valve |10 to pipe |68 which raises gate |62, thus allowing a sufficient amount of stock to by-pass through opening to restore the balance between the weighted beam and the feed pressure. If the feed pressure falls below the balanced value, adjustment in the opposite sense is effected. With the arrangement above described any predetermined suitable feed box pressure may be automatically and positively maintained within a satisfactory range of variation. The extent of movement of the free end of beam |13 may be limited by adjustable stops |84 and |85. A pin |86 projects from the beam laterally and in position to be engaged with a cam action by a curved portion of one arm |81 of a lever pivoted at |88, the other arm |89 being provided with a weight which in one position locks the beam out of operation, and in the other permits the beam to move freely between the stops |84 and |85.

From the foregoing description and stated mode of operation of one form of apparatus embodying my invention, it appears that the feed control so provided is automatic and positive.

Furthermore, the system may also be hand controlled by closing valve 200 and manually regulating the effective opening of valve |88.

Although shown in connection with a mill of the colloid type, i. e., wherein material is treated by film shearing, it is contemplated that my control apparatus may be effectively applied to control feed pressure in the operation of other kinds of material treating or handling devices wherein, for example, solid material in solution, mixture, or suspension in a fluid is fed thereto under pressure.

I claim:

l. Feed pressure control apparatus for a conduit adapted to feed paper pulp or the like which includes in combination a diaphragm, a feeler pipe having one end opening at one side of said diaphragm and the other end opening into said conduit for transmitting static pressure in the conduit to said diaphragm, a source of water pressure independent of pressure in the conduit and a water supply pipe connected to admit a controlled volume of water from said independent source to said feeler pipe between said end openings.

2. Feed pressure control apparatus for a conduit adapted to feed paper pulp or the like which includes in combination a diaphragm, a feeler pipe having one end opening at one side of said diaphragm and the other end opening into said conduit for transmitting static pressure in the conduit to said diaphragm, a source of water pressure independent of pressure in the conduit, and means for controllably delivering into said feeler pipe a supply of water from said independent source to act as a moving and renewable static pressure transmitting element between said diaphragm and material under pressure in said conduit.

JAMES T. COGHILL.

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