US3044625A

US3044625A - Load indicator for centrifugal separator

Info

Publication number: US3044625A
Application number: US694241A
Authority: US
Inventors: William C Smith; Clyde K Henninger
Original assignee: Ametek Inc
Current assignee: Ametek Inc
Priority date: 1957-11-04
Filing date: 1957-11-04
Publication date: 1962-07-17
Anticipated expiration: 1979-07-17
Also published as: GB906270A; NL6403676A

Description

y 1 1962 w. c. SMITH ETAL 3,044,625

LOAD INDICATOR FOR CENTRIFUGAL SEPARATOR Filed Nov. 4, 1957 33 26 Fl G 3 L as ,-' 37 INVENTORS.

38 I as WILLIAM c. SMITH 5 y K. HENNINGER A TORNEY 7 3,044,625 LOAD INDICATOR FOR CENTRIFUGAL SEPARATOR William C. Smith, Moline, and Clyde K. Henmnger, Geneseo, Ill., assignors to Ametek, Inc., a corporation of Delaware Filed Nov. 4, 1957, Ser. No. 694,241 3 Claims. (Cl. 210-86) The present invention relates to centrifugal separators, and particularly to a new and improved load indicator for centrifugal separators. I

The operation of centrifugal separators often includes the controlledfeediug of a slurry or the like to the rotating basket of such a separator. The duration of feeding is often controlled in the cyclic operation of such separators by a timing device. In many instances, the

, solids concentration of the slurry may vary during the cyclic operation of a separator'so that a greater volume of solids is fed to the basket within a predetermined time preset on the timing device. In such instances, overloading of the basket may occur with the attending difiiculties of overloading the apparatus and/or the loss of such slurry through the discharge opening of the apparatus prior to its being centrifuged. 7

Many attempts have been made to provide load indi cators for centrifugal separators with varying degrees of success. One drawback of known indicators is the turbulence and splashing caused in the material .being treated when the indicating elements contact the material. This action produces excessive strains and stresses in the indicator which operate to reduce its efficiency and life. Additionally, it is often'desirable to avoid excessive turbulence of the material being treated, particularly where undesirable fumes and mist might be produced which upon escaping would constitute a hazard.

The principal object of this invention is to provide a load indicator of simple construction which will be effective to indicate the load of a centrifugal separator with: out disturbing the condition of the material being treated, while still being capable of efficient operation and long life. V

Another object of this invention is to provide a load indicator that can be adjusted for various densities of material to be treated so that a substantially uniform action of the indicator will occur regardless of the material being treated.

Another object of the invention is to provide a load indicator'thatcan be preset for a desired response to suit particular operating conditions. A

Another object of this invention is to provide a load indicator that will cause a centrifugal separator to which it is applied to process a maximum load of solids regardless of the solids concentration in the, slurry, so long as the feed timer is set to allow the collection of a full basket of solids when the slurry contains the minimum percentage of solids-concentration. v

'One aspect of the invention may be to provide an oscillatable shaft that vertically extends into the basket of V a centrifugal separator on which may be fixedly mounted of the oscillatable shaft may be provided with a rigid arm that may cooperate with a spring loaded microswitch or the like that may be normally closed, and adapt-ed to be opened when the oscillatable shaft is turned Unit States atent f I Patented July 17, 1962 by coaction between the thin blades and the material being treated. The micro-switch maybe connected into the timing circuit including the feed valve, so that should the load within the rotating basket become excessive during the preset timed interval on the timer, the feed valve can be closed off until the load is normal, at which time the feed valve may be reopened to continue the feed.

The above, other objects and novel features of the invention will become-apparent from the following specification and accompanying drawing which is merely exemplary.

In the drawing:

FIGURE 1 is a partial elevational view of a centrifugal separator to which the principles of the invention have been applied;

FIG. 2 is a top plan view of the load indicator and looking in the direction of the arrows along line 2 -2 of FIG. 1; and

FIG. 3 is an enlarged sectional elevational view taken substantially along line 33 of FIG. 1.

Referring to the drawing, and particularly to FIG. 1, the principles of the invention are shown as applied to a centrifugal separator of the bottom discharge type, although they may with equal facility be applied to any type of centrifugal separator. The separator shown may include a bed plate 10 on which are mounted three equally spaced pedestals 11 (only two being shown) that include mechanism for supporting a housing 12 for limited oscillatable movement. The housing 12 may have fixed to its sides brackets 13 that extend into the pedestals 11 for cooperation with supporting mechanism therein.

A basket 14 having a top opening 14' may be located within the housing 12 and may comprise a perforated cylindrical member for passing liquid therethrough, which liquid is collected within an annular chamber within the housing 12. The bottom of the basket 14 may be provided with discharge passages for gravitating solids collected within the basket incident to the centrifuging of the material being treated. v

The basket may be provided with a multiple V-belt sheave (not shown) on a vertically disposed spindle to which the basket 14 may be fixed. \l-belts 15 may connect the sheave on the basket spindle with another sheave (not shown) on the axis of rotation of an hydraulic motor 16 that is adapted to be operated at varying rates of speed for loading, separating and discharging material to be treated.

The top of the housing 12 may be provided with a top plate 17, and a cover plate 18 of semicircular form, mounted on a hinge pin 19, may cover a correspondingly shaped opening the top plate 17 to provide access to the interior of the basket 14.

A feed pipe 20 may extend from the exterior of housing 12 through the top plate 17 and open into the basket 14 along its vertical axis of revolution. The inner end of pipe 20 may extend through an opening 21 within the top of a truncated, conical distributing member 22 that may be fixed to the rotatable spindle that supports the basket 14 and, therefore, feed cone 22 rotates with the basket 14. The flow of material to be treated through the pipe, 20 may be started or stopped by the operation of a solenoid valve (not shown) which may be controlled by a preset timer (not shown).

A plate 23, having an opening 24 therein, may be fixed to the top plate 17 in a manner such that opening 24 coincides with a similar opening 25 within the top plate 17. A load indicator L may be mounted on plate 23 and extend vertically into the basket 14 through its top opening 14.

Referring to FIG. 3, the load indicator L may include a tubular support 26 that may be held in a predetermined vertical position by

releasable clamping members

27 and 28. One of the

members

27 or 28 may be fixed to plate 23, while the other may be unattached, but clamped around the tubular member 26 and held to the other member by bolts 29 and 30.

The tubular support 26 may be counterbored at each end to receive aligned

bearing glands

31 and 32 which may be of any material such as bronze, babbitt, nylon or the like. A cylindrical shaft 33 may extend through the support 26 and be held in vertically adjustable position by a collar 34 fixed thereto and resting on the flange of gland 32.

The lower end of shaft 33 is reduced in diameter providing a shoulder 35, and a plurality of thin blades 36 may be fixed to shaft 33 by a key 37. Spacers 38 may be employed to separate the blades 36, and a washer 39 may be removably fastened to the lower end of shaft 33 in a manner to hold the assembly of blades 36 and spacers 38 in proper relationship. The arcuate extent of the blades 36 may be varied, as may the vertical spacing and number thereof, to suit the operating conditions which prevail.

A bracket 40 may be fixed to plate 23, and it may support a normally closed switch 41 of the so-called micro-switch variety. An operating arm 42 having a roll 43 thereon may extend from switch 41 into the arcuate path of movement of a lever 44 fixed to the collar 34 which, in turn, is fixed to the shaft 33. A collar 45, fixed to the stationary tubular support 26, may support spaced

pins

46 and 47 defining the extent of arcuate movement of the lever 44. Resilient means 41 may force the arm 42 in a clockwise direction (FIG. 2), holding switch 41 closed and arm 44 against stop 47. This is the condition before blades 36 contact the material in the basket.

The switch 41 may be wired in series into the timing circuit of the solenoid valve that controls the feeding of material to be centrifuged through the feed pipe 20. With the apparatus in the condition shown in FIG. 1, the material fed through the pipe 20 is distributed through the opening 22 of the feed cone 22 by centrifugal force. It exits from opening 22 in the form of a thin, circular sheet which is directed against the side walls of the rotating basket 14, where it moves upwardly and downwardly until an annular layer of the material to be treated covers the inner side wall surface of the perforated basket 14. This annular wall increases in thickness as more material is fed through the pipe 20. The timer for the solenoid valve is usually preset so that a known quantity of material for a given batch is treated. However, should the thickness of the annular layer of material on the inner wall of basket 14 increase at a too rapid rate so that the apparatus would tend to become overloaded, or fail to drain as fast as it is being fed through pipe 20, the inner peripheral surface of this rotating annular layer of material will Wipe over the blades 36, causing the shaft 33 and arm 44 to move in a clockwise direction (FIG. 2) thereby moving arm 42 in a counterclockwise direction, whereupon switch 41 is opened and the solenoid valve for controlling the feed of material through the pipe 20 is closed until such time as the inner peripheral surface of the rotating material recedes from blades 36 when the switch will automatically close, re-energizing the feed solenoid and continuing the feed of the material through the pipe 2t).

Although the various features of the new and improved load indicator have been shown and described in detail to fully disclose one embodiment of the invention, it will be evident that numerous changes may be made in such details, and certain features may be used without others without departing from the principles of the invention.

What is claimed is:

1. In a centrifugal separator having a rotatable basket, means for feeding material into said basket; means for rotating said basket as said material is fed thereinto, whereby said material is rotated and forms an annular shell on the inside of said basket; a load indicator extending into said basket, said indicator including a shaft; separately removable oscillatable thin blades keyed to said shaft; spacers between said blades for maintaining them in spaced planes normal to the inner peripheral surface of said shell of material; removable means at the one end of said shaft for maintaining said blades and spacers on said shaft, whereby the number of blades may be varied to provide a predetermined sensitivity of said indicator for materials having different densities; and means responsive to the engagement between said blades and said shell for oscillating said blades for stopping the feeding of material to said basket.

2. A load indicator for a centrifugal separator com prising in combination, a tubular support; aligned bearings within said tubular support; a shaft journaled in said bearings and extending beyond both of said bearings; a plurality of separately removable thin blades keyed to the one end of said shaft and extending radially therefrom in aligned relation and in parallel spaced planes; separately removable spacers between said blades; removable means at the one end of said shaft for: maintaining said blades and spacers on said shaft, whereby the number of blades may be varied to provide a predetermined sensitivity of said indicator for materials having different densities; and a switch operating arm fixed to the opposite end of said shaft.

3. Apparatus comprising in combination, a support; a tubular member adjustably clamped to said support and extending through an opening therein; aligned bearings within said tubular member; a shaft journaled in said bearings and extending beyond both of said bearings;

separately removable thin blades arranged in aligned relation keyed to one end of said shaft; separately removable spacers between said blades; removable means at the one end of said shaft for maintaining said blades and spacers on said shaft, whereby the number of blades may be varied to provide a predetermined sensitivity of said indicator for materials having different densities; an arm fixed to the other end of said shaft; and a switch mounted on said support and including an arm resiliently urged into engagement with the arm on said shaft.

Steps Jan. 11, 1938 Hertrich May 3, 1955