US 3115096 A
Description (OCR text may contain errors)
Dec. 24, 1963 K. B. WALL 3,115,096
PUMP UNIT Filed Feb. 1, 1961 2 She ets-Sheet 1 W WTIWHQ 55 J 21a 1 I[ 15 21 l 11 Dec. 24, 1963 K. B. WALL ,1
PUMP UNIT Filed Feb. 1, 1961 2 Sheets-Sheet 2 United States Patent 3,115,896 PUMP UNIT Karl Berti! Wall, Jonkoping, Sweden, assignor to Jonkopings Mekaniska Werkstads AB, .lonkoping, Sweden Filed Feb. 1, 1961, Ser. No. 86,431 Claims priority, application Sweden Feb. 3, 1960 Claims. (Cl. 10387) This invention relates to a pump unit of the type comprising a vertical centrifugal or turbine pump, a motor or another driving means located above the pump and coupled thereto, and a supporting device carrying the driving means and interconnecting the pump and said driving means.
Centrifugal pumps of existing types, such as pumps with single-sided or double-sided suction, pumps with one or more runners, and pumps having axially or ra dially divided pump casing are, to a great extent journalied horizontally. When this is the case, the pump and its associated motor are mounted on a common base plate. Such a pump unit suffers, however, from certain drawbacks. For example, the base plate often requires a large floor space and/ or necessitates a special bed of concrete. Furthermore, it is necessary to adapt the base plate, for one and the same type of pumps, to motors of diiferent sizes, which involves recurrent amendments of drawings and perhaps extensive alterations of design. On account of this, procuring and installing such a pump unit is relatively expensive.
On account of this and other circumstances a vertical mounting of pumps has been preferred, to some extent and this offers several advantages. For instance the floor space required is reduced, and special beds of concrete are, in most cases, not necessary. Furthermore the motor gets such a position that it runs much less risk of becoming splashed or flushed with the fluid pumped in case of leakage. On the other hand it has not been possible to obviate some deficiencies. Thus the pump casing is often mounted on a socle of cast iron provided with a base plate and adapted to serve, at the same time, as a suction pipe, which results in a complex and expensive construction.
Pumps are also known in which the pump casing, or a housing for a suction inlet and bearings, are formed as a holder for supporting means for the motor, which increases the costs of manufacture. etaching of the pump necessitates, in the constructions of the prior act, dismounting of the entire pump unit, when the pump carries the motor, and even the removal of such vital parts as the impeller or pump wheel and the bearing devices thereof, involves usually great difficulties and can sometimes necessitate removal of the entire pump unit from the tube line. Due to the complex design of vertical pumps of the prior art, these ordinarily become more expensive than horizontal pump units. The pump casing of other pumps has a bottom cap or cover and is cast integrally with a supporting means for the drive motor and with a bearing shell, thereby making the runner or rotor wheel accessable, but such a construction is complicated and not entirely reliable.
The prime object of the invention is to provide a pump unit of the kind described in which all these drawbacks are removed in a simple Way.
With this and other objects in view the pump unit according to the invention is characterized in that the supporting means is formed as a frame extending below the pump and in which the pump is removably suspended, so that pump and driving means are removable individually; that the shafts of the pump and the driving means, which shafts are at least approximately aligned with each other, are united by means of an universally articulated, removable intermediate shafts; and that a bearing shell 3,115,696 Patented Dec. 24, 1963 provided with bearings for the pump shaft is secured to a cover forming the upper portion of the pump casing, said bearing shell being liftable upwards together with the pump wheel as one rotor unit, when the intermediate shaft is detached, and then removable in transverse direction through an opening in the frame.
One embodiment of a pump unit according to the invention will be described more in detail below with reference to the accompanying drawing, in which FIG. 1 is a side view of a one stage pump unit, partly in section; and
PEG. 2 is a section on line IIII in FIG. 1.
The pump casing 1 which is provided with one-sided inlet and outlet 2 and 3 respectively is supported by a frame or framework comprising three tubular legs 4, 5 and 6 respectively of forge iron or steel. To the lower end of each tube 4, 5, 6 a respective foot plate 7, 8 and 9 respectively is secured as by means of welding. Said plates have openings for bolts by means of which the legs are secured to the fioor or another base.
The lower portion of each leg is vertical, and the upper portions of the legs are bent slightly inwards. The upper ends of the legs are welded to a common ring 10 onto which an electric motor is fastened by means of bolts 12. During the welding a fixture may be utilized for assuring an exact positioning of the legs with respect to each other. The pump casing is cast with three radially projecting shoulders 13 for its suspension thereby upon the legs to which the pump casing is secured by means of bolts 14 and washers 15 with angular contact surfaces facing the legs, so that the pump casing is freely suspended above the base. As appears from FIG. 2 the legs 4, 5, 6 are located at the corners of a triangle, the spacing between the legs being determined by the facts that the shoulders 13 should have a suitable location on the pump casing, and that at least one of the interspaces between the legs has to be wider than the diameter of the cover of the pump casing, so that the cover may be easily removed. As each leg 4, 5, 6 is clamped in three points the frame gets great rigidity in spite of its low Weight.
The pump wheel 16 is fastened upon the free end of the pump shaft which is journalled in one upper antifriction bearing 18 and two lower anti-friction bearings 19. These bearings are mounted in turn outs or recesses in the end portions of a tubular bearing shell 20 and are retained, at the upper end, by a flange 21 rigidly fastened to the shaft 17 and, at the lower end, by an annular socket 2-2 supporting a packing ring 23 and a sealing device 24. The socket 22 has a peripheral, radially projecting flange 25 which is clamped, by means of bolts, between a flange projecting from the bearing shell 20 and supporting shoulders 26 on the cover 27 of the pump casing. If the fluid to be pumped should leak through or penetrate the scaling device 24 it is drained off through a drilled hole 28 in the socket 22 to prevent fluid from penetrating the packing ring 23 and reaching the antifriction bearings.
The cover of the pump casing is secured thereto by means of bolts 29 and is provided with a lower collar 30 which is directed outwardly and co-operates with a flange 31 projecting from the pump wheel. Sealing between socket 22 and cover 27 may be obtained in any suitable manner known per se.
The motor shaft and the pump shaft are connected by an intermediate shaft comprising two members 32, 33 which are telescopically slidable in relation to each other and provided with guides preventing angular displacement of the shaft members with respect to each other. The member 33 is connected to the pump shaft by means of an universally articulated end portion 36 and a plate 21a rigidly attached thereto, and secured to the flange 21 by means of bolts, and the member 32 is similarly connected to a coupling 34 fastened to the motor shaft. A protective wire screen 35 or the like is arranged around the shafts connected in this way.
As appears from the drawing it is possible, after loosening the bolts 29 and the universal joints to remove the intermediate shaft, and then lift up the pump wheel 16, the pump shaft 17, the cover 27, the socket 22 with its seals, and the bearing shell 20 as one unit and remove this unit in transverse direction without having to loosen the motor or the tube lines. Thus, it is easy to inspect these vital parts of the pump replace damaged parts by new ones. Such a unit or certain parts thereof may be kept in reserve for quick mounting, if a defect should arise.
On account of the intermediate shaft in the form of a universal driving shaft or a flexible shaft there is no need of the pump shaft and the motor shaft being exactly coaxial, and therefore careful adjustment of the motor in relation to the pump shaft is not necessary.
The spacing in vertical direction between pump and motor is also permitted to vary within certain limits, due to the telescopicity of the intermediate shaft. On account of this design the function of the unit will not be jeopardized by small mutual displacements of the parts after a dismounting.
Due to the movability or flexibility of the intermediate shaft the requirements as to the fastening of the pump casing are not so rigorous. As furthermore the frame according to the invention extends below the pump, it is not necessary to provide the pump casing with any means for supporting the motor. Therefore the pump casing may be designed primarily with regard to the specific hydraulic conditions and hereby becomes very simple, light and inexpensive in manufacture. As is evident from the embodiment described above the pump casing may be made without any supporting flanges cast integrally therewith, which flanges involve increased weight and necessitate complex mandrels. The movability or fiexability of the intermediate shaft also reduces the requirements with regard to the rigidity and accuracy of the pump casing thus permitting the selection of a flexible construction which is simple and cheap in manufacture and may be easily adapted to different sizes of the motor. In the embodiment described the rings 10 may be kept in stock in dimensions corresponding to the motor sizes utilized, and tubes for the legs 4, 5, 6 may be stored ready-bent so that only possible cutting is required before their welding together to a frame. Pumps of different types, such as one stage pumps with double-sided inlet, may also be suspended in the frame, which may easily be adapted to pumps of different sizes or types by this standardization. Instead of an electric motor it is also possible to use another driving means of any suitable kind. Vertical pumps of the prior art have, as a rule, a frame of substantially semi-circular cross section between pump and motor thereby permitting the removal of the rotor unit in one direction only, which necessitates the manufacture of right hand pumps as well as left hand pumps. In contradistinction to this the frame of the assembly according to the invention may be made, as a rule, in such a manner, that the rotor unit can be removed in two or three different directions thereby requiring only one design of the pump and assuring independence of local conditions.
The disclosed embodiment of the pump unit may be further modified in various ways within the scope of the invention. Thus, the pump may have only one leg secured to the base, and this leg may branch into two or more shanks supporting pump and motor. The suction inlet may also open into the pump from below, although the inlet is lateral in the embodiment described. It is also possible to arrange a gearing, a hydraulic coupling or the like between pump and motor to meet the increased demand for a speed control. In lieu of the universal joint shaft shown in the drawings it is also possible to utilize a shaft which is flexible or elastical in its entirety, or a shaft the ends of which are detachably fastened to the motor and pump shafts by means of elastical coupling means, thus providing axial as well as bending and torsional elasticity. In the last mentioned case the telescopic means may be dispensed with. Furthermore it is obvious that the invention may be applied even in those cases when the centrifugal pump is adapted to transport or circulate a gas instead of a liquid and thus constitutes a fan or blower.
What I claim is:
1. A pump unit comprising in combination:
a vertical centrifugal pump provided with a pump casing;
a pump wheel located in said casing; a pump wheel shaft to which said pump wheel is secured;
a removable driving means located above the pump and provided with a shaft;
a supporting frame provided with at least one opening and carrying the driving means;
suspension means in said frame in which suspension means said pump is removably suspended, said pump and said driving means thus being removable independently of each other;
a coupling means, including a removable intermediate shaft, non-rigidly interconnecting the shafts of the pump wheel and the driving means, which shafts are approximately aligned with each other;
a cover forming the upper portion of said pump casing; and
a bearing shell provided with bearings for the pump shaft and removably secured to said cover, said bearing shell being liftable upwards together with the pump wheel as one rotor unit when the intermediate shaft is detached, and then removable in transverse direction through said opening.
2. A pump unit as claimed in claim 1, in which the frame comprises tubular legs jointly supporting the pump and provided, at their lower ends, with foot plates having means for anchoring the legs in a base.
3. A pump unit as claimed in claim 2, in which said legs are bent and each comprise an upper inclined portion and a lower substantially vertical portion, said inclined portions diverging outwards-downwards from each other.
4. A pump unit as claimed in claim 1, in which said intermediate shaft is a universal joint shaft.
5. A pump unit as claimed in claim 1, in which the intermediate shaft is united with the shaft of said driving means and said pump shaft by means of elastic connecting means.
References Cited in the file of this patent UNITED STATES PATENTS 1,552,056 Iversen Sept. 1, 1925 1,704,481 Lawaczeck Mar. 5, 1929 1,767,535 Lannert et al. June 24, 1930 1,991,761 McHugh Feb. 19, 1935 2,265,940 Forrest Dec. 9, 1941 2,939,402 Ygge June 7, 1960 2,947,260 Hornschuch Aug. 2, 1960