Pump Arrangement with Speed Control

Abstract

A pump arrangement for bodies of water or containers with water subject to biological influences has at least one water pump and a control device controlling the speed of the water pump. At least one temperature sensor measures the water temperature and provides signals of the measured water temperature. The signals are processed in the control device and the speed of the pump water is controlled by the control device based on the signals.

Description

BACKGROUND OF THE INVENTION

The invention concerns a pump arrangement with at least one water pump and a control device for its speed, wherein the water pump is designed for circulating water in bodies of water subject to biological influences, for example, ponds, aquariums, or fountains. Such water pumps can be used for supplying filters as well as for operating water displays or fountains and/or, in other ways, improve gas exchange or oxygenation as well as, in winter, provide protection of the body of water from freezing by water circulation. Bodies of water or containers with water in which such water pumps are used can be subject to biological influences by changing ambient temperatures and water temperatures. Further biological effects are, for example, the turbidity of the body of water, possible contamination load, changes of the oxygen contents or the like.

At higher temperatures the biological reaction rate is increased also in a body of water and this causes an increased oxygen consumption. It is therefore expedient to operate such water pumps at an increased speed when higher temperatures are present so that the circulation rate of the water is accordingly adjusted. In conventional water pumps, this control of the speed is done manually, i.e., the operator of such a water pump monitors the biological effects on his body of water and controls then the speed of the water pump for adjusting the circulated water volume accordingly. Since this requires a continuous monitoring of the body of water and of the environmental effects, the water pump is often operated for most of the year underfull load, i.e., at maximum speed, because of laziness, without this being necessary. This consumes an unnecessary amount of energy.

SUMMARY OF THE INVENTION

The invention has therefore the object to provide a pump arrangement that makes possible energy savings and whose operating comfort is increased.

According to the invention this object is solved by a pump arrangement that is provided with at least one temperature sensor for measuring the water temperature, whose signals are processed in the control device and used for controlling the speed of the water pump. By using a temperature sensor and connecting it to the control device, the measured temperature values are directly and automatically employed for controlling the speed of the water pump. A fully automated operation of the water pump in optimal output and speed ranges is therefore possible throughout the year without requiring manual intervention.

The pump arrangement can be designed to be especially comfortable with regard to operation and flexible with regard to its application when the control device comprises control electronics and a data memory with control software. The control software can be exchanged as needed when basic conditions of the body of water, for example, its size, the number of fishes, the plant life, or other climatic or biologic conditions change significantly.

Preferably, in the data memory a temperature limit as a maximum temperature is stored; when this temperature limit is reached or surpassed, the control device causes the water pump to always run at maximum speed. For temperatures below the upper temperature limit, temperature limits for partial loads can be preset at which a stepped adaptation of the pump speed is realized. For a temperature increase of 10 Kelvin the biological reaction rate and thus also the oxygen consumption will double; the control is therefore designed preferably such that, because of this, the circulation rate, i.e., the speed, will be doubled also.

In order to ensure that at low temperatures, for example, operation in winter, an optimal gas exchange and the required oxygenation take place, and to also ensure protection from freezing over, it can be expedient to again increase the speed and thus the circulation rate of the water pump, instead of lowering it more, when the temperature drops below a minimum temperature stored within the data memory.

One possible energy-saving configuration of the water pump could be selected such that at water temperatures of 6 to 8 degrees Celsius a minimal water quantity of 3,500 l/h is circulated. At temperatures between 8 degree Celsius and 20 degree Celsius the water quantity and the rate of circulation could to be increased continuously or in a stepwise manner. For example, an average speed can be provided at temperatures between 15 and 18 degrees Celsius. Starting at a temperature limit of 20 degrees Celsius, the water pump should then be operated at maximum speed for maximum circulation.

Increase of the speed of the water pump at increasing water temperatures can be done in a linear fashion. As a result of the increase of the biological reaction rate, at least for some temperature ranges an exponential increase is however expedient in many cases.

The pump arrangement according to the invention is preferably utilized in water pumps with an electronically commutated drive (EC pumps). It is especially advantageous in this connection to integrate the control device and the temperature sensor directly into the water pump. However, it is also possible to provide external electronics and/or sensors that are also used in connection with conventional asynchronous or synchronous water pumps.

BRIEF DESCRIPTION OF THE DRAWINGS

One embodiment of a water pump with integrated control device will be explained in the following with the aid of one embodiment shown in the figures. It is shown in:

FIG. 1 a schematic cross-section of a water pump according to the invention; and

FIG. 2 a section in the direction II-II of the object of FIG. 1.

DESCRIPTION OF PREFERRED EMBODIMENTS

The illustrated water pump has a housing 1 with an intake 2 through which the water enters the water pump and a pressure connector 3 through which the water exits from the water pump. The water is conveyed by means of impeller 4 that is driven through shaft 5 by means of an electric motor 6. The electric motor 6 has a rotor 7 that is caused to rotate by an electromagnetic field generated by coils 8. A can 9 separates the area 1′ of the housing 1 through which area water passes from the electric area 1″ of the housing 1 that is to be kept dry. Preferably, in the electric area 1″ the control electronics 11 are arranged by which the speed of the motor and thus of the water pump is controlled. In the interior of the housing, a temperature sensor 12 is also arranged that measures at the position of the arrow 13 the temperature of the water that is conveyed past the sensor. The temperature sensor 12 is connected to the control electronics 11 in a way not illustrated in the drawing.

Preferably, the temperature sensor 12 is arranged such that it receives as little as possible of the heat generated by the water pump in order to be able to measure a substantially unadulterated water temperature. An especially advantageous position of the temperature sensor 12 is illustrated in FIGS. 1 and 2. The arrangement of the temperature sensor 12 is selected such that it is located precisely at the transition between the area 1′ of the housing through which the waterflows and the electric area 1″ of the housing. In this way, the temperature can be measured in the area where the water flows through while a technically safe and dry connection to the control electronics 11 in the electric area 1″ of the water pump is possible. Advantageously, the temperature sensor 12 is received for this purpose in the flange of the can 9. This position is optimized in that the temperature sensor is to be arranged at a spacing as large as possible from any of the coils 8 of the pump motor 6. In the case of the star arrangement of the coils 8 as illustrated, such an advantageous position of the temperature sensor 12 is precisely centered within a free segment between two coils (see FIG. 2).

At the topside of the housing there is a switch 14 that is accessible from the exterior by which via a connection, not illustrated, to the control electronics 11 the control action as a function of the water temperature, measured by the temperature sensor 12, can be switched on or off. By means of this switch a change between manual control and automatic operation is possible.

In addition to the temperature sensor 12, the entire pump arrangement can have additional sensors, for example, for detecting water turbidity or the actual oxygen contents. These signals can also be evaluated by the control electronics and can be incorporated into the speed control through the control software. However, since the most important parameter is the water temperature, pump arrangements that have only a temperature sensor are already very effective and save, in comparison to conventional, manually controlled water pumps, a significant amount of energy as a result of an always optimal operation. Such pump arrangements can be operated all year long almost without any maintenance and expenditure. Their control software can be considered essentially an annual biological program because an automatic adaptation of the water pump performance to the seasons and the thus resulting operational necessities is achieved. In addition, the control software can take into account also further calendar-based or time-of-day-dependent parameters and, in this way, the water pump can be adapted even better to the needs of the operator and of the body of water in which it is used.

The specification incorporates by reference the entire disclosure of German priority application 10 2006 027 002.9 having a filing date of Jun. 8, 2006.

While specific embodiments of the invention have been shown and described in detail to illustrate the inventive principles, it will be understood that the invention may be embodied otherwise without departing from such principles.

Claims

1. A pump arrangement for bodies of water or containers with water subject to biological influences, the pump arrangement comprising:

at least one water pump;

a control device controlling a speed of the water pump;

at least one temperature sensor measuring water temperature and providing signals of the measured water temperature, wherein the signals are processed in the control device and the speed of the pump water is controlled by the control device based on the signals.

2. The pump arrangement according to claim 1, wherein the control device comprises control electronics and a data memory with a control software.

3. The pump arrangement according to claim 1, wherein in the data memory a temperature limit is preset, wherein the control device adjusts the water pump to operate at maximum speed when the temperature limit is reached.

4. The pump arrangement according to claim 2, wherein in the data memory temperature limits for partial loads of the water pump are provided, wherein the control device adjusts in steps the speed of the water pump based on the temperature limits.

5. The pump arrangement according to claim 2, wherein the control electronics control the speed of the water pump continuously.

6. The pump arrangement according to claim 2, wherein the control electronics control the pump speed lineraly at least for some water temperature ranges based on the measured water temperature.

7. The pump arrangement according to claim 2, wherein the control electronics control the pump speed exponentially at least for some water temperature ranges based on the measured water temperature.

8. The pump arrangement according to claim 1, wherein the control device is integrated into the pump.

9. The pump arrangement according to claim 1, wherein the water pump has a switch for actuating the control device, wherein the switch is accessible from the exterior of a housing of the water pump.

10. The pump arrangement according to claim 1, wherein the at least one temperature sensor is integrated into the water pump.

11. The pump arrangement according to claim 10, wherein the at least one temperature sensor is arranged in the interior of a housing of the water pump.

12. The pump arrangement according to claim 10, wherein water pump has a pump motor with coils, wherein the at least one temperature sensor is arranged within the housing of the water pump at a distance as large as possible from each of the coils of the pump motor.