英文文献.docx

1、英文文献SUCTION NOZZLE FOR A VACUUM CLEANER, COMPRISING A DUST FLOW DISPLAY DEVICEAbstractA suction nozzle for a vacuum cleaner that can be connected to a suction pipe and/or a suction tube of the vacuum cleaner includes a nozzle part （吸盘部分）that can be connected to the suction pipe or the suction tube b

2、y means of a tubular connection part. A dust sensor is arranged in the flow path of the vacuum cleaner, the signals thereof being evaluated by a battery-operated electronic control device that can be activated by a Low-pressure switch. During operation, said control device controls a display device

3、displaying the dust flow. The control device，the low-pressure switch, the display elements displaying the dust flow, and a battery compartment for receiving the batteries are arranged in a housing formed on the upper side of the tubular connection part. The dust sensor is arranged beneath the housin

4、g，inside the upper region of the connection part，in the dust air stream.FIELD OF THE INVENTION The present invention relates to a suction nozzle for a vacuum cleaner, said suction nozzle being connectable to a suction wand and/or to a suction hose of the vacuum cleaner, the suction nozzle having a n

5、ozzle part which is provided with a suction mouth and is connectable to the suction wand or to the suction hose of the vacuum cleaner via a tubular connection part, the suction nozzle including a dust-flow sensor which is disposed in the flow path of the vacuum cleaner and whose signals are analyzed

6、 by an electronic control device, and, during operation, the control device controlling an indicating device which indicates the dust flow.BACKGROUND For quite some time，there has been a desire to provide vacuum cleaners with a measuring and indicating device that allows the user to assess how the l

7、evel of cleanliness of the surface to be treated varies during the vacuum cleaning process. In fact，it would be of great help to the operator if he or she could see from an indicating device that，after a certain vacuum cleaning time，there remains hardly any dust-laden air being conveyed through the

8、flow- conveying system of the vacuum cleaner, so that the vacuum cleaning process is not unnecessarily prolonged. To remedy this，a number of proposals have been made in the patent literature，but these proposals have not yet led to any implementation that would be relevant in practice. For example，it

9、 is known from European publication EP 0231 419 A1 to provide an indicating and control device in the form of an attachment or accessory for a vacuum cleaner, said indicating and control device being installable in the flow-conveying system of the vacuum cleaner. This indicating and control device s

10、hould be activatable by a low-pressure switch and operate with optical dust-detecting means .It was also proposed to mount this unit on the vacuum cleaner or its parts (suction brush，suction wand, handle, suction hose) at a position adjacent to the suction region of the vacuum cleaner. That prior pu

11、blication does not include any specific information on how and where to install the sensor which is at the heart of such a system. There is no known practical implementation based on this design approach. A practical embodiment in which the dust-flow sensing and indicating device is mounted in a suc

12、tion nozzle is described in DE 93 11014 U1and DE 202 07 071 U1，respectively. Both design approaches have in common that the sensing and indicating device is located in the bottom part of the suction nozzle. In DE 93 11 014 U1，a removable sub-housing is provided above the bottom part of the suction n

13、ozzle to accommodate the sensor and the indicating elements .The sensor is formed by optical dust-detecting means provided in the inlet duct or in the inlet region of the bottom part of the suction nozzle. The floor nozzle depicted in that prior publication illustrates the drawbacks of this embodime

14、nt particularly well .Since the additional elements(sensor, battery-operated control device, and indicating devices) are accommodated directly in the bottom part of the suction nozzle，the size of the bottom par is inevitably increased. Therefore, it is no longer possible to move such a suction nozzl

15、e into the narrow free spaces under furniture .Moreover, in cases where the bottom part of the suction nozzle does disappear under a piece of furniture，the indicating device is no longer visible. Furthermore, the bottom part of the suction nozzle, in particular, is inevitably exposed to strong shock

16、s .This may easily lead to failures of the control electronics located in the bottom part and of the sometimes fragile sensor elements. These are certainly the crucial reasons why, up to the present time，no suction nozzle having an indicating and sensing device mounted directly in the bottom part of

17、 the suction nozzle could be established in the market to an appreciable extent. All design approaches described above are based on providing a sensor in the form of an optical dust-detecting means which, for system-inherent reasons alone，has certain draw-backs. It is not very easy to provide an opt

18、ical measurement section in the confined mounting space in the flow channels of the air-conveying system of a vacuum cleaner. Moreover, an optical measuring system is not sufficiently reliable and accurate for certain purposes. A particular disadvantage of optical systems is that, in addition to the

19、 actual dust, they also respond to carpet fibers resulting from wear and tear of a carpet，but do not allow any conclusions about the level of cleanliness. In contrast, a design approach described in EP 0759 157 B1 is particularly advantageous in that it uses a piezoelectric sensor device which allow

20、s even minute dust particles to be reliably detected without the signal being affected so much, for example，by carpet fibers. The embodiment described in that patent proposes for the piezoelectric sensor to be mounted in the inlet tube or in an inlet connector of the vacuum cleaner. When the dust pa

21、rticles present in the air-flow path hit the piezoelectric sensor they transfer part of their energy to the sensor, the piezoelectric sensor converting the kinetic energy into a corresponding electrical signal (piezoelectric voltage). That prior publication does indeed describe the physical sensor s

22、ystem and the electronic control system in detail，but it does not provide any details on where and how to install the individual elements-sensor, control electronics, indicating device and, possibly, a battery provided for power supply.SUMMARY OF THE INVENTION It is an object of the present inventio

23、n that a sensing and indicating device be accommodated in the air-flow path of the vacuum cleaner in such a manner that the components involved in the overall system are installed in a space-saving and ergonomically favorable manner. A further or alternate object is to find an installation location

24、for the sensor, whichhas favorable flow characteristics and ensures trouble-free and reliable operation. The present invention provides a suction nozzle for a vacuum cleaner, said suction nozzle being connectable to a suction wand and/or to a suction hose of the vacuum cleaner, the suction nozzle ha

25、ving a nozzle part which is provided with a suction mouth and is connectable to the suction wand or to the suction hose of the vacuum cleaner via a tubular connection part, the suction nozzle including a dust sensor which is disposed in the flow path of the vacuum cleaner and which is located in the

26、 dust-air stream inside the upward portion of the connection part and whose signals are analyzed by an electronic control device, during operation，the control device controlling an indicating device which indicates the dust flow, the indicating elements indicating the dust flow being disposed in a h

27、ousing or receiving chamber formed on the upper side of the tubular connection part, wherein the dust sensor is insertable underneath the housing through an opening formed on the upper side of the connection part and protrudes into the dust-air stream near the upper wall area of the connection part.

28、 Advantageous embodiments and refinements of the present invention will become apparent from the claims（权利要求书）. The present invention also provides an accessory or retrofit solution in the form of a separate connection part，which can be connected，as an independent part，directly to a floor nozzle of

29、the vacuum cleaner. The present invention provides significant advantages .It was found that especially the upwardly directed connection part of the suction nozzles is particularly suitable for accommodating the sensor, control and indicating system. Nevertheless，the bottom part or the suction mouth

30、 part of the suction nozzle can still be of flat construction. In addition, by forming an attachable housing on the upper side of the connection part or the upward connector member, all components can be accommodated in a manner which is ergonomically favorable and compatible with styling requiremen

31、ts. The battery compartment，for example，is easily accessible， and the batteries are very easy to replace. Moreover, the indicating elements，which indicate the condition of the suction air stream in the generally known manner by means of indicating LEDs，can be installed such that they are easily risi

32、ble to the user. This display window is always in the direct line of sight of the user, because during vacuum cleaning，he or she is always looking along the suction wand toward the suction nozzle area. Another, particularly essential features are that the piezoelectric sensor（压电传感器） is mounted on th

33、e lower side of the upper wall of the connection part. This decisively contributes to the special method of operation of the system. When heavy parts and particles are still present in the suction air stream, these are conveyed by the dust-air stream generally beneath the sensor and into the collecting chamber system of the vacuum cleaner. T