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Publication numberUS20070258827 A1
Publication typeApplication
Application numberUS 11/416,663
Publication dateNov 8, 2007
Filing dateMay 2, 2006
Priority dateMay 2, 2006
Publication number11416663, 416663, US 2007/0258827 A1, US 2007/258827 A1, US 20070258827 A1, US 20070258827A1, US 2007258827 A1, US 2007258827A1, US-A1-20070258827, US-A1-2007258827, US2007/0258827A1, US2007/258827A1, US20070258827 A1, US20070258827A1, US2007258827 A1, US2007258827A1
InventorsDaniel Gierke
Original AssigneeDaniel Gierke
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Sump pump system
US 20070258827 A1
Abstract
A programmed microcontroller based sump pump system includes multiple pumps that can be employed with one as a primary pump and one as a back-up, or can be employed in combination to increase the discharge rate. The microcontroller monitors the back-up battery condition, and computes and displays the battery life; monitors the system for clogs or vapor locks in the discharge piping; switches to an emergency periodic pumping mode of operation, when needed; and notifies the user by phone or e-mail of a system malfunction.
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Claims(20)
1. A sump pump system for removing liquid from a sump comprising:
a plurality of pumps for pumping liquid from the sump, said pumps being arranged to be selectively powered from a primary power source and a secondary battery back-up power source;
a battery back-up power source; and
a programmed microcontroller based controller unit for controlling said pumps and selecting said power source therefor.
2. The sump pump system of claim 1 wherein said controller unit is programmed to selectively operate said pumps either individually or in combination.
3. The sump pump system of claim 1 wherein said controller unit is programmed to selectively operate one of said pumps as a primary pump and to selectively operate one of said pumps as a secondary, back-up pump.
4. The sump pump system of claim 1 wherein said controller unit is programmed to selectively operate one or more of said pumps in an emergency mode by periodically cycling said respective pump ON and OFF.
5. The sump pump system of claim 1 wherein said controller unit is programmed to provide a display or alarm in the event of a malfunction.
6. A sump pump system for removing liquid from a sump comprising:
a pump driven by an electric motor for discharging liquid from the sump, said pump being arranged to be selectively powered from a primary electrical power source or a secondary battery back-up power source;
a battery back-up power source; and
means for computing the expected life of said battery back-up power source, said means including a programmed microcontroller.
7. The sump pump system of claim 6 wherein said means for computing said expected life of said battery back-up power source comprises:
selecting a starting value for said battery life;
determining the expected rate of power consumption by the sump pump system; and
computing said resultant expected battery life, wherein said computation is based on said starting value and said rate of power consumption.
8. The sump pump system of claim 7 further comprising adjusting said starting value of said battery life for recent usage of said battery.
9. The sump pump system of claim 6 further comprising:
display means for displaying said computed expected life of said battery back-up power source; and
alarm means for providing an alert and/or alarm in response to said computed expected battery life.
10. The sump pump system of claim 8 further comprising:
a secondary pump driven by an electric motor for discharging liquid from the sump, said secondary pump being arranged to be selectively powered from a primary electrical power source or a secondary battery back-up power source;
a programmed microcontroller based controller unit for controlling said pumps and selecting said power source therefor;
display means for displaying said computed expected life of said battery back-up power source; and
alarm means for providing an alert and/or alarm in response to said computed expected battery life.
11. A sump pump system for removing liquid from a sump comprising:
a pump driven by an electric motor for discharging liquid from the sump through discharge piping;
a programmed microcontroller based controller unit for monitoring and operating said pump and for monitoring the liquid level in the sump; and
means for sensing the electrical current flowing to said pump motor and thereby determining the existence of a vapor lock condition in said discharge piping, said means including said programmed microcontroller.
12. The sump pump system of claim 11 wherein said controller unit programming comprises:
switching OFF said pump on detection of a low current flow to said pump motor;
counting the ON/OFF cycles of said pump within a preset period; and
determining a vapor lock condition in response to said count of ON/OFF cycles.
13. The sump pump system of claim 11 further comprising means for detecting a discharge blockage, said means including monitoring by said microcontroller of the liquid level in the sump during operation of said pump.
14. The sump pump system of claim 13 wherein said means for detecting a discharge blockage includes a repeating cycle comprising:
monitoring the liquid level in the sump; and
operating said pump during a predetermined time interval following detection of a predetermined liquid level.
15. The sump pump system of claim 14 further comprising alarm means for providing an alert and/or alarm in response to a sensed vapor lock condition or a sensed discharge blockage.
16. A sump pump system for removing liquid from a sump comprising:
a pump for discharging liquid from the sump through discharge piping;
a programmed microcontroller based controller unit, said microcontroller being programmed to detect a notification event, operate a modem, and communicate with a remote computer;
a remote programmed computer system accessible by said microcontroller through a phone line connection; and
a modem under control of said microcontroller for providing a phone line communication connection to said remote computer.
17. The sump pump system of claim 16 wherein said programming of said microcontroller comprises:
detecting a possible notification event;
determining, in response to said detected event, whether communication to said remote computer system is required;
connecting to said remote computer system by placing a telephone call through said modem to a predetermined phone number; and
transmitting to said remote computer system a serial number for the sump pump system and a code for the notification event.
18. The sump pump system of claim 17 wherein said remote computer system is programmed to respond to said transmission from said microcontroller by accessing a database, retrieving an e-mail address from said database corresponding to said serial number of said sump pump system, and sending an e-mail notification through the internet to said e-mail address.
19. The sump pump system of claim 17 wherein said remote computer system is programmed to respond to said transmission from said microcontroller by accessing a database, retrieving a phone number from said database corresponding to said serial number of said sump pump system, and sending a notification in the form of a pre-recorded voice message to said phone number.
20. The sump pump system of claim 18 wherein said notification event includes one or more of the following: an electrical failure, a clog in the discharge piping, a vapor lock in the discharge piping, a pump failure or activation error, an electrical power failure, a failure of a sensor, or a disconnected battery.
Description
CROSS REFERENCE TO RELATED APPLICATIONS

Not Applicable

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

Not Applicable

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates generally to pumps used to remove water or other liquid from a sump or pit. More particularly, this invention relates to apparatus for monitoring and improving the reliability of a sump pump system, and in a further feature, to direct user notification of malfunctions or failures in the sump pump system.

2. Description of the Prior Art

It is well known in the prior art to provide a pump within a pit or sump that operates from an electrical power line power source. Moreover, to improve the reliability of such prior art pump system, it is also known to add a secondary back-up pump which is powered by a back-up battery power source. Consequently, when there is a power failure that causes the power to the primary pump to be interrupted, the battery powered back-up pump is automatically switched ON by appropriate relay circuitry.

These prior art systems, however, have presented several drawbacks:

(1) They have no way of increasing the pump discharge rate when a higher discharge is needed to keep pace with liquid flowing into the sump.

(2) There is no monitoring of the condition of the back-up battery or display to the user of the expected battery life.

(3) There is no monitoring of the plumbing and a clog or vapor lock in the discharge pipes will go undetected.

(4) Finally, the prior art systems have no way of notifying the user of a failure within the system.

SUMMARY OF THE INVENTION

The primary objects of the present invention include the following:

(a) providing a more reliable and versatile sump pump system;

(b) providing a sump pump system with an adjustable pump discharge rate;

(c) providing system monitoring and operational safeguards;

(d) providing direct notification to the user of malfunctions.

These and other objects are accomplished in the present invention by the following:

(1) A computer based controller unit is used to operate the sump pump system and includes a programmed microcomputer (microcontroller). Particularly, this controller unit monitors the plumbing, the battery, the pumps, and the liquid level in the sump; it controls the sump pump system; and it alerts and notifies the user.

(2) A multiple pump design under control of the controller unit includes a plurality of pumps arranged to be operated either on a power line electrical power source or on battery power, and to be operated either individually or in combination, as needed.

(3) A battery monitoring feature of the controller unit detects the battery condition, computes the expected battery life, and displays the expected battery life to the user.

(4) A plumbing monitoring feature of the controller unit detects outlet clogs and vapor locks in the system and provides an alert and/or alarm in response to a detected problem.

(5) An emergency mode of operation feature of the sump pump system provides for limited periodic pumping.

(6) A direct user notification feature of the sump pump system notifies the user by phone and/or e-mail in the event of a malfunction, system failure or other defined notification event.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagrammatic elevation view of a sump pump system in accordance with the present invention.

FIG. 2 is a block diagram of the primary components of the sump pump system of FIG. 1.

FIG. 3 is a block diagram of the programming logic of the microcontroller for sensing a plumbing clog and alerting the user.

FIG. 4 is a block diagram of the programming logic of the microcontroller for sensing a vapor lock in the plumbing and alerting the user.

FIG. 5 is a block diagram view of the programming logic of the microcontroller for computing and displaying the expected battery life of the back-up battery.

FIG. 6 is a block diagram of the programming logic of the user notification routine of the controller unit.

FIG. 7 is a block diagram of the programming logic of the notification routine at the remote computer for receiving the error notification from the controller unit and notifying the user.

While the invention will be described in connection with a preferred embodiment, it will be understood that it is not the intent to limit the invention to that embodiment. On the contrary, it is the intent to cover all alternatives, modifications, and equivalents as may be included within the spirit and scope of the invention as defined by the appended claims.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Turning first to FIG. 1 there is shown a representation of a sump or pit 10 and a pump system in accordance with the present invention for evacuating liquid from the sump. (This pump system may be employed in addition to any other pump system currently in the sump or as the sole pump system in the sump.) Positioned within the sump 10, a first pump 12 and a second pump 14 are shown; but it is to be understood that multiple additional pumps may be employed in the same manner as herein described, and such is considered to be within the scope of this invention.

The pumps of the present invention are preferably identical electrical motor driven pumps of the usual submersible variety well known in the art for operation within a sump environment, and they are connected therein in the usual manner for pumping liquid from the sump when switched ON. For purposes of this description, the reference herein to a pump being switched ON, or being in an ON condition, shall mean the condition of having electrical power provided to its electric motor, such that the pump is operating, i.e., pumping. Conversely, the reference herein to a pump being switched OFF, or being in an OFF condition, shall mean the condition of not having electrical power provided to its electric motor, such that the pump is not operating, i.e., not pumping.

Also shown in FIG. 1 is discharge piping 16. This discharge piping is connected to the pumps in the usual configuration for conveying the liquid evacuated from the sump 10 by the pumps, and includes the usual check valves 18 a and 18 b for preventing backflow therein.

A back-up battery 20 (preferably a 12 volt, 105 amp, lead-type marine battery) is located proximate the sump 10 and provides back-up power to the sump pump system in the event of a failure in the main power line electrical power source. This battery is electrically connected to the pump motors in the usual manner and is arranged to be selectively switched into service by a programmed microcontroller based controller unit 22, more fully described below.

Providing the primary power to the entire sump pump system, including the pumps and the controller unit 22, is a power line electrical power source connection 24. This power source is monitored by the controller unit 22; and when a power failure is sensed, the controller unit switches the system to the aforesaid back-up battery as the power source.

To facilitate user notification (described in detail below), whereby the user is directly notified of an error or malfunction in the system, a telephone line 26 is also connected to the sump pump system. As will be more fully understood later, this user notification is accomplished by means of a programmed remote computer 30 arranged to be accessible to the controller unit 22 via the telephone line connection 26.

Positioned within the sump 10 for sensing the level of liquid therein is a liquid level sensor 32. In the present invention, this level sensor is arranged to provide an analog signal to the controller unit 22 when the level reaches a pre-selected high level for the initiation of a pumping cycle. The liquid level sensor used herein is a well known float-type reed switch designed for submersible use; but alternatively, this sensor may comprise any equivalent level sensing device known to the art for use in sump pump systems. When connected with the usual circuitry and in a manner well known to the art, the liquid level sensor herein provides a certain signal (a high voltage output) when the liquid level is high enough to float the switch. This signal is detected by the microcontroller of the controller unit, as hereinafter described.

The monitoring and control functions of this sump pump system are accomplished with a programmed microcontroller based controller unit 22 (see FIG. 2), which controller unit includes a programmed microcontroller device 34, switches or relays 36 for switching the pumps, current sensor circuitry 37 for monitoring the electrical current flowing to the pump motors, alarm means 38, display means 40, and a phone modem 42. In the preferred embodiment a PIC18 microcontroller (model PIC18F4620) is used for the microcontroller, and it is available commercially from Microchip Technology, Inc. (The employment, interconnection, and programming of this microcontroller is well known to the art.) Conveniently included with this microcontroller are a number of analog to digital converters which are accessible as analog inputs to the microcontroller 34. These analog inputs are used for directly monitoring the sump pump system, e.g., battery voltage, battery charge current, pump motor current, and liquid level sensor voltage.

The basic operation of the pumps is performed by the controller unit 22. When the level sensor provides a signal (high output voltage), that voltage is sensed at one of the aforesaid analog inputs to the microcontroller 34; and in response, under basic programming known to the art, the controller unit 22 causes the relays 36 to switch, thereby activating one or more pumps. In this manner, the controller unit may selectively employ the pumps in any one of a variety of configurations:

(a) Any one pump may be operated individually.

(b) Two or more pumps may be operated in combination, thereby selectively increasing the discharge rate for the sump pump system.

(c) One pump may be operated as a primary and one or more as secondary back-ups.

(d) One or more pumps may be operated in a periodic pumping cycle, as an emergency mode.

Monitoring of the condition of the battery is another one of the basic functions of the controller unit 22, and for that purpose the battery voltage is also detected at one of the aforesaid microcontroller analog inputs. During normal operation of the sump pump system using electrical power line power, when a low battery voltage is sensed by the microcontroller, it will selectively cause the battery to be charged from the power line source, thereby maintaining the battery in a fully charged condition. This detected battery voltage will also be used for tracking the power available from the battery and for computing the expected “battery life” (described below) in the event the battery is needed as a back-up power source.

In a further aspect of its monitoring function, the microcontroller 34 of the controller unit 22 detects, through one of its aforesaid analog inputs, the electric current being drawn by the pump motors during their respective operation. This current detection is performed in conjunction with current sensor circuitry 37, which circuitry is well known in the art; and the voltage output from this current sensor circuitry is fed to an analog input of the microcontroller 34 for monitoring. An analysis of this detected current by the microcontroller is then used to determine the condition of the plumbing pursuant to programming logic described hereinafter.

User feedback about the condition of the sump pump system and the plumbing is provided in the form of alerts, alarms, displays and direct notification. Particularly, alarm means 38, under control of the microcontroller 34, provides an alert and/or alarm for the user, and this alarm means 38 may be either audible or visual, or both. Similarly, display means 40 is utilized for providing feedback in the form of a display for the user, which display means is also controlled by the microcontroller 34. In the preferred embodiment, this display means 40 comprises a liquid crystal display, commonly known as an LCD, the connection and employment of which is well known to the art. Also under control of the microcontroller 34 for user notification is a phone modem 42. This modem is used for providing communication with the remote computer 30 through the phone line 26, and is employed for direct user contact by telephone and/or e-mail, as more fully described below.

In a further feature of the present invention, a blockage in the plumbing is determined upon the detection of the following condition: the pumps are operating and the liquid level sensor 32 is continually reporting a high level of liquid in the sump. Accordingly, there is provided herein means for detecting this discharge blockage, said means including monitoring by the aforesaid programmed microcontroller 34 of the liquid level in the sump during operation of the pumps. The programming of the microcontroller 34 of the controller unit 22 for this detection of a discharge blockage is depicted in the flow diagram of FIG. 3 and explained as follows.

When the pre-selected liquid level for the initiation of the pumping cycle is detected, the controller unit 22 turns ON the first pump 12 (pump #1) if it is not already ON and continues to monitor the liquid level through the liquid level sensor 32. If the liquid level, as indicated by the level sensor, remains high, then the controller unit will turn ON the second pump 14 (pump #2), thereby increasing the discharge rate from the sump. (In the example described herein, two pumps are employed, but it should be noted that similar logic applies whether one pump is being employed or whether multiple pumps are being employed, and this invention is not to be limited to the use of any particular number of pumps.) In the present embodiment, with both pumps ON the controller unit continues to monitor the liquid level and keeps the pumps ON for a defined first interval of pumping time, e.g., one minute. After such defined first interval of time, and with both pumps operating, if the liquid level still remains high, then a clog is suspected; and, by means of the aforesaid alarm means, an alert and/or alarm is generated to indicate that the plumbing is possibly clogged. (Additionally, and as a further aspect of this clog detection feature, a direct notification to the user may be initiated, as more fully described below.) If the above liquid level sensing and pumping cycle routine is still being repeated after a defined second time interval, e.g., two hours, the existence of the clog is now confirmed; then by way of the aforesaid alarm means, another alert and/or alarm is triggered signaling a confirmed plumbing blockage. Finally, the pumps are shut OFF. (It should be noted that the time allotted for pumping until final shutdown will depend on whether the pumps are being powered by the battery back-up or the electrical power line.) After shutdown of the pumps, the controller unit preferably switches the pump operation to the emergency mode discussed below and initiates a direct user notification.

Similar to a clog, a vapor lock will also prevent effective operation of the pumps. A vapor lock condition occurs when air is trapped in the pipe between a pump and the check valve. A typical pump installation provides a small hole in the pipe near the bottom of the sump to alleviate this condition; but still, due to either faulty installation or clogging of the hole, vapor locks sometimes develop in the discharge pipes. Consequently, when a pump is switched ON and a vapor lock occurs in the piping, the pump (in a typical prior art system) will run continuously but will not remove liquid from the sump.

The sump pump system of the present invention comprises means for sensing the electrical current flowing to the respective pump motors and thereby determining the existence of a vapor lock in the discharge piping, said means including the programmed microcontroller 34. Particularly, it has been determined that the flow of electrical current to a pump motor is significantly higher when the pump is pumping liquid than when there is no liquid being pumped, whether due to an empty sump or the existence of a vapor lock. As a result, the amount of electrical current determined by the microcontroller as flowing to a pump motor will indicate the possible presence of a vapor lock. Therefore, the controller unit 22, through the programmed microcontroller 34, determines a possible vapor lock by sensing a low electrical current flow to the pump motor. This current flow is monitored at one of the aforesaid analog inputs of the microcontroller 34, as previously described, and analyzed by the microcontroller 34.

The sequence of the programmed logic for vapor lock detection is illustrated in the flow diagram of FIG. 4 and described as follows. The liquid level sensor 32 first senses the preset depth of the liquid for initiation of pumping and its signal is detected by the microcontroller 34 of the controller unit 22, thereby causing a pump to be switched ON. (The same logic and sequence of events described here applies to each pump when it is switched ON.) When the pump is switched ON, the controller unit automatically starts monitoring the electrical current being drawn by the respective pump motor. Upon detection of a low current condition for that pump, the microcontroller switches the pump OFF and starts a timer. If the pump turns ON again within this first time interval, a suspected vapor lock condition is declared, and by way of the aforesaid alarm means, an alert and/or alarm is provided to the user. After a defined second interval of time and a preset number of repeated ON/OFF switching cycles, a vapor lock condition is confirmed; and by way of the aforesaid alarm means, a confirming alert and/or alarm is triggered. A direct notification of this event can also be sent to the user through the remote computer, as described below. Finally, after a pump is determined to have a vapor lock, that pump is shut OFF and, optionally, may be switched to the emergency mode described below.

During the operation of this sump pump system, it is expected that the power line electrical power source will occasionally fail; and during such times the controller unit 22 is programmed to switch the power source for the sump pump system to the battery back-up, store information on battery usage, compute the expected battery life, and display that information for the user. For this purpose, means for computing the expected life of the battery back-up power source is employed, wherein said means includes the aforesaid programmed microcontroller 34 of the controller unit 22. (The logic of the programming of the microcontroller for performing this function is shown in FIG. 5 and described below.)

As illustrated in the logic flow diagram of FIG. 5, the computation program begins with an initial starting value for the battery life. This initial value represents the power or charge available from the battery and depends upon the specific battery being used. The microcontroller then checks for the charge status of the battery and any recent use or power draw on the battery and adjusts the initial value accordingly. Next, the microcontroller determines the expected rate of consumption of the battery charge based on the known requirements of the pumps, the level sensor, and the controller unit; and it uses that rate of consumption and the anticipated power available from the battery to calculate its effective life. While the sump pump system remains on battery power, this expected battery life calculation routine is repeated periodically, e.g., every fifteen minutes; and the resulting expected battery life is displayed by the display means 40. In the event that the charge remaining in the battery is too low and the expected battery life is too short, an alert and/or alarm is provided by the alarm means 38. Finally, in order to maintain the operation of the controller unit for as long as possible, when the battery charge reaches a predetermined low level, the pumps will no longer be switched ON, and all remaining power will be conserved for use by the controller unit.

Upon detection of a plumbing blockage, vapor lock, sensor failure, or other event which prevents normal operation of the sump pump system or makes normal operation inadvisable, the controller unit 22 is programmed to switch the pumps to an emergency mode. In this emergency mode, one or more pumps are operated periodically, i.e., by cycling one or more of said pumps ON and OFF at timed intervals. In the preferred embodiment any pump that is switched to emergency mode is operated (switched ON) for a preset interval of time every few minutes, and then switched OFF.

In addition to feedback by alarm and display, the sump pump system of the present invention includes direct notification to the user. This notification is accomplished by phone and/or e-mail and will be initiated by the controller unit 22 upon the detection of an error, alert, or other notification event, e.g., a blockage in the discharge piping, a vapor lock in the discharge piping, a disconnected battery, a failure of the liquid level sensor, a pump failure or activation error, or an electric power failure. A flow diagram of the call notification sequence is shown in FIGS. 6 and 7 and starts with the detection of the notification event. Following a determination by the controller unit that a call to the remote computer system is required, the programmed microcontroller 34 enables the phone modem 42 and initiates a telephone call to a predetermined phone number. (The phone modem 42 is of the type commonly used for computer-to-computer communication, the employment and programming requisite therefor being well known in the art.) That call is automatically answered by the similarly programmed remote computer 30 via a complementary phone modem 45 (said programming of this remote computer also being well known in the art). After the call is answered by the remote computer, a serial number and error codes are automatically transmitted by the controller unit 22 through the phone line to the remote computer. When this serial number and error code information is received, the remote computer (FIG. 7) looks-up the serial number in a database of registered user information and, upon verification of the registered user, returns an acknowledgment through the modems and the phone line 26 to the microcontroller 34 of the controller unit. On receipt of this acknowledgment, the microcontroller disconnects the phone line connection and resumes its other programmed functions.

At the remote computer 30, the e-mail address and phone number of the registered user is retrieved from the database and one or both of the following automated notifications are sent to the user describing the problem encountered by the sump pump system. To the user's e-mail address, an automated e-mail notification is sent in the usual manner via the internet, the means and technique of e-mail transmission being now well known in the art. This internet based e-mail transmission may be accomplished by the employment of the phone line connection to the internet or other equivalent means known to the art. Preferably, the e-mail notice includes specific identification of the user's sump pump system as well as information on the error occurring at the site. To the user's phone number, an automated voice call is made, audibly identifying the sump pump system and the error. This voice call is accomplished by means of a device commonly referred to in the computer industry as a “voice board.” When installed with the programmed remote computer 30, this voice board enables the computer initiated phone call to deliver a realistic voice recording to the user, identifying both the system and the problem. This remote computer 30 initiated phone call hardware and programming is also currently well known in the art.

From the foregoing description, it will be apparent that modifications can be made to the apparatus and method for using same without departing from the teachings of the present invention. Accordingly, the scope of the invention is only to be limited as necessitated by the accompanying claims.

Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US7762788 *Jul 31, 2007Jul 27, 2010Seiko Epson CorporationFluid conveyance system and fluid conveyance device
US7849890 *Jul 1, 2005Dec 14, 2010Lockheed Martin CorporationApparatus for and methods of draining an enclosure
US7934279 *Oct 31, 2007May 3, 2011Lg Electronics Inc.Method for sensing a supply of water to a water-droplet generator of a laundry machine
US20110311370 *Jun 17, 2011Dec 22, 2011Sloss Jeffrey ASump pump system with remote control and monitoring
Classifications
U.S. Classification417/6, 417/411, 417/44.11, 417/36
International ClassificationF04B49/06, F04B41/06
Cooperative ClassificationF04D13/068, F04D15/029
European ClassificationF04D15/02F