Patent Application
20140328704
This application claims foreign priority benefits under 35 U.S.C. §119(a)-(d) to European patent application number EP 13166461.7 filed May 3, 2013, which is incorporated by reference in its entirety.
The disclosure relates to a motor pump assembly, in particular to a portable motor pump assembly.
In such motor pump assemblies, a standard method of construction has prevailed in which the oil housing is exposed in an unprotected manner, quasi bare in the respective operating position. This is partly justified by the fact that direct heat dissipation into the environment is to support the cooling effect of the cooling fan. Examples of such motor pump assemblies can be found in EP 0 198 250 A2, DE 38 39 689 A1, CH 596 697 A5, U.S. Pat. No. 6,589,029 B1, EP 1 731 762 A1, EP 0 284 746 A1.
In motor pump assemblies known from EP 1 045 143 A1 and EP 2 025 934 A1, the cooling fan is arranged respectively on an end of the closure lid closing the oil housing, coaxial to and driven by the shaft of the electric motor. The cooling fan is covered by a hood that overlaps the closure lid and deflects the cooling air initially directed towards the outer side of the closure lid and guides it along the side walls and the cooling fins arranged thereon. The side walls with their cooling fins are exposed.
In a motor pump assembly known from EP 1 179 677 A1, the massive-walled metal oil housing is closed at both ends by closure lids. The motor shaft passes through one closure lid. A cooling fan is mounted on the exterior of this closure lid, coaxial to the motor shaft and driven by the motor shaft. The cooling fan is covered by a hood that deflects the cooling air initially directed towards the closure lid and guides it along the side walls and between the cooling fins arranged there. The side walls with the cooling fins are exposed.
When a motor pump assembly with a hydraulically operated tool is used in the field, for example, with a torque wrench, a cable lug clincher, with metal sheet or accident scissors and the like, then the relatively slim object, which is long due to the cooling fan on the end sides, is not only cumbersome to transport and to set up, but it has shown that cooling efficiency is unsatisfactory where the cooling air flow of the cooling fan on the end side is relatively uncontrolled at the side walls. This leads to disadvantage, in particular during prolonged or continuous operation. A relatively large amount of heat is namely during operation of the motor pump assembly generated by the electric motor and also by the hydraulic oil heating up, which during operation collects in the motor pump assembly and needs to be efficiently dissipated to protect the seals and the oil itself as well as the electric motor. Under changing environmental conditions, the commonly finned oil housing tends to dirty relatively quickly whereby the cooling effect is reduced even further. In addition, the appearance is very strongly influenced by purely technical features and collisions that are in practice unavoidable during transport and operations possibly also result in damage to the cooling fins.
An object of the disclosure is to improve a motor pump assembly of the kind mentioned above in terms of the achievable cooling effect, in particular when operated in the field, of the outer appearance, and of protection against environmental influences.
The at least one cooling fan arranged on at least one outer side cools surprisingly better than at least one end-side cooling fan, also due to the fact that the outer housing furthers selective guidance of cooling air blown by the cooling fan against and not along the side wall. Overall, higher and more uniform cooling performance of the cooling fan results for the same energy input. The outer housing is a multifunctional outer housing, as it serves not only to guide the flow of cooling air, but also covers the cooling fan towards the exterior, prevents any access from the exterior to the cooling fan, protects against direct influence of dirt and weather upon the oil housing and, possibly protects sensitive equipment components, buffers collisions when operated in the field and keeps them away from the oil housing, and ultimately even conveys a pleasant appearance of the motor pump assembly due to its compactness. The arrangement of the cooling fan on the side wall further reduces the overall height of the motor pump assembly, which with the cladding of the outer housing overlaps the side walls, has an easily manageable size. Moreover, the outer housing can be well used for more auxiliary functions and it possibly improves the standing stability of the motor pump assembly.
In a preferred embodiment, the cooling fan is fitted with an electric drive motor behind inlets of the outer housing on the side wall of the oil housing. In this manner, cool air from the exterior is sucked in and distributed selectively on the side walls of the oil housing by the cooling fan and the outer housing, i.e., in a region in which the electric motor generating heat in the interior of the oil housing and the largest part of the oil reservoir containing the heat are disposed. The inlets can optionally be combined with an air filter in order to minimize contamination and wetting of the side walls of the oil housing, in particular of the cooling fins.
In an advantageous embodiment, the cooling fan has an outer casing (encapsulated design) and the outer housing, as a border of the cooling air inlets, has an inner frame encompassing the outer casing of the cooling fan. In this manner, inter alia improved air guidance is forced into the cooling fan.
In order to also account for high cooling demand, it is advantageous if even on two side walls of the oil housing facing away from each other, at least one cooling fan is respectively disposed in the interior of the outer housing. In this way, all the side walls of the oil housing can be cooled intensively and efficiently. One cooling fan is optionally used on each side wall.
In a favorable embodiment, the oil housing, having an approximately quadrangular, possibly slightly rounded outer contour, comprises cooling fins extending longitudinally on the outer side to provide the cooling air with as large a surface as possible. Preferably the respective cooling fan is with a supporting frame being C-shaped in cross-section positioned at a distance from the cooling fins and fixed with hooks latched behind cooling fins of two adjacent side walls. This simple but secure way of attachment also makes it possible to select the optimum position of the cooling fan in the longitudinal direction of the oil housing as needed.
In a favorable embodiment, the outer housing comprises two housing halves which can be designed substantially in mirror-image and three-dimensionally, and each of which comprises housing walls overlapping three adjoining side walls and the ends of the oil housing. In this way, the oil housing is largely covered by the outer housing and protected from external influences.
It can here be advantageous if each housing half is integrally formed, though assembling each housing half from several individual parts is not excluded.
In order not to damage the delicate cooling fins, it is advantageous to have the outer housing be attached to at least one end or even to both ends of the oil housing, preferably with screw feet on a mounting side end and with attachment screws on the opposite end. This sturdy way of attaching the outer housing increases the protective effect for the oil housing.
At least one console is advantageously attached to the outer housing with mounting screws fixing the outer housing at an upper end of the oil housing and comprises at least one suspension eye and/or a carrying handle. This improves handling of the motor pump assembly when operated in the field, for example, for transporting the motor pump assembly with a hoist onto the nacelle of a wind turbine, or for conveniently carrying it over long distances, where the compact and almost cube-shaped design of the motor pump assembly with the cooling fan housed at the side increases in the field [sic]. The outer housing could even have floor rollers.
Furthermore, the outer housing can assume another function in that it comprises external cable holders, for example, for an electrical connecting cable and/or a control cable connected to a remote control. The cable or cables can then be easily stowed during transport or when not in use.
The outer housing is advantageously made of plastic and/or metal, for example sheet metal. The design made of plastic can, for example, make use of injection-molded parts. A simple creased and/or screwed and/or welded construction is suitable for sheet metal or metal. The outer housing, in particular made of plastic, is very light but nevertheless sturdy due to the three-dimensional outer housing halves. A multi-material design of the outer housing is also possible.
The outer housing comprises at least one blow-out port for warm cooling air. A blow-out port is advantageously designed and arranged such that it externally encompasses the manifold block and a terminal box with an assembly control unit attached thereto, i.e., that the terminal block as well as the assembly control unit are accessible from the exterior and efficiently maintained cool by the cooling air flow blown out and the cooler external environment. Because magnets on the distribution block and the electronic control unit generate heat that is harmful to them.
Furthermore, it can be advantageous to provide a slot-like blow-out port in the outer housing also at the side wall of the oil housing facing away from the manifold block and extending in the longitudinal direction of the oil housing that preferably can extent approximately along the entire length of the oil housing and can provide the flow of a relatively high cooling air flow rate acting in a self-cleaning manner. The blow-out port or the blow-out ports can further be sized such that a dynamic pressure being optimal for the cooling effect forms in the interior of the outer housing.
In order to finally further increase the protective effect for the oil housing, elastic pads can be provided between the outer housing and the oil housing which not only with a thin-walled outer housing prevent any contact between the outer housing and the oil housing, but also stabilize the thin walls of the outer housing.
One embodiment according to the disclosure shall be explained with reference to the below drawings.
As required, detailed embodiments are disclosed herein; however, it is to be understood that the disclosed embodiments are merely exemplary and that various and alternative forms may be employed. The figures are not necessarily to scale. Some features may be exaggerated or minimized to show details of particular components. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a representative basis for teaching one skilled in the art.
On the outer housing 2, a console 1 is fixed to the upper side of the motor pump assembly M with attachment screws 33 that also provide for the attachment of the outer housing to an upper end 21 (
From the interior oil housing 18,
The outer housing 2 is composed, for example, of two substantially mirror-image housing halves 15, 16 made of plastic and/or sheet metal which are also at the lower end 21′ (
According to
At least one cooling fan G is according to an embodiment of the disclosure disposed on at least one side wall 19 between the upper and lower ends 21, 21′ and attached, for example, to the oil housing 18 or in the outer housing 2. The cooling fan G in an outer casing 22, for example, with a square end flange, comprises an electric drive motor 23 and a fan wheel—not further highlighted—and is mounted to a side wall 19. A C-shaped frame 24 can be used for mounting which is supported between cooling fins 20 and the side wall 19 and fixed with attachment hooks 25 latched behind cooling fins 20 of two adjacent side wall 19.
In the embodiment shown, even two cooling fans G are provided mounted on side walls 19 facing away from each other. The number and distribution of the cooling fans G on the side walls 19 can be higher or different than shown.
Cooling air inlets 26 (slots or holes) are formed in the outer housing 2, i.e., in each housing half 15, 16 in orientation towards the cooling fan G. An air filter can possibly be fitted in this region.
As indicated on the left housing half 16 in
Each housing half 15, 16 is formed three-dimensionally and advantageously in an integrally formed manner (for example, an injection-molded part), but can also be assembled from individual sections. In this, each housing half 15, 16 comprises walls 28, 31, 40, 30, 29 overlapping at least three side walls 19 of the oil housing 18, so that the oil housing 18 is practically enclosed on all sides. Alternatively, if appropriate, the lower end 21′ of the oil housing 18 could be not covered by the outer housing 2. The outer housing 2 can with openings 35 in the wall sections 29 additionally be fixed to the lower end 21′, i.e., not only with the console 1 and the attachment screws 33, to the upper end 21.
Elastic pads 34 are advantageously inserted between the outer housing 2 and the oil housing 18.
The front-side blow-out port Al with the edge 14 has already been explained with reference to
The assembled outer housing 2 is used not only for protecting the oil housing 18, but also for the selective distribution of cooling air at least on the side walls 19 in order to intensify the cooling effect when the cooling fan G is in operation.
While exemplary embodiments are described above, it is not intended that these embodiments describe all possible forms of the invention. Rather, the words used in the specification are words of description rather than limitation, and it is understood that various changes may be made without departing from the spirit and scope of the invention. Additionally, the features of various implementing embodiments may be combined to form further embodiments of the invention.
| Number | Date | Country | Kind |
|---|---|---|---|
| 13166461.7 | May 2013 | EP | regional |
