EP1693499A2 - Swingably suspended inner assembly of a washing machine, method for controlling a washing machine and use of an electronic sensor as a movement sensor in an inner assembly - Google Patents

Abstract

The inner assembly (2) is suspended such that it can vibrate in a laundry treatment machine. The assembly has a laundry drum (4) and a drive such as electric motor (8), for driving the laundry drum. A vibration sensor is rigidly coupled to a component of the internal unit. The vibration sensor is an electronic sensor. The vibration sensor is based on a measurement principle using capacitive effects and or inductive effects and or piezoelectric effects. A printed circuit board and the vibration sensor is a printed circuit board module on the printed circuit board. An independent claim is included for a method for controlling a washing machine and use of an electronic sensor as a movement sensor in an inner assembly.

Description

The invention relates to an oscillating suspended indoor unit of a laundry treatment machine, which comprises a laundry drum and designed as an electric motor drive the laundry drum. Furthermore, the invention relates to a method for controlling a laundry treatment machine, wherein the oscillatory movements of an internal unit of a laundry treating machine are measured and the use of an electronic sensor in the indoor unit.

The internal assembly of a washing or spinning machine usually comprises a tub with rotatably mounted laundry drum and a drive unit in the form of an electric motor which drives the laundry drum often via a reduction gear or a transmission. The indoor unit is suspended vibratory in a machine or machine housing and represents a damped oscillatory overall system, which is subject to unbalance dependent resonance phenomena in certain areas of the motor speed reduced speed of the laundry drum. This is due to oscillatory movements due to momentary imbalances in the loading of the laundry drum.

Such oscillating movements as a result of imbalances can be counteracted in the program sequence of a washing or spinning machine by means of a targeted laundry dispensing phase. For this purpose, the control program for the drum drive is only then switched to an increased speed for dehumidifying and spin-drying the laundry in the laundry drum, if in the course of such a laundry distribution phase the imbalances have been compensated or at least reduced to a level suitable for the introduction of increased speeds.

For detecting such an imbalance in the laundry drum, it is known from DE 37 41 791 C3 and EP 0 349 789 B 1, to use a so-called tachogenerator as a rotary encoder. This is connected to the motor shaft and generates a respective speed of the laundry drum corresponding signal voltage whose frequency is proportional to the speed. The signal delivered by the tachogenerator thus represents, so to speak, the actual speed of the laundry drum, which varies depending on the imbalance of the laundry in the laundry drum. Such a tachogenerator as a rotary encoder thus detects those components of a swinging motion of a swingably suspended internal assembly of a washing machine, which lead to a corresponding angular acceleration or torque fluctuation about this axis of rotation.

The invention has for its object to provide a particularly suitable device for detecting a swinging motion of a vibratory suspended indoor unit of a laundry treatment machine with an electric motor driven laundry drum and a corresponding method.

This object is achieved by the features of claim 1.

According to the device according to claim 1, an oscillating suspended indoor unit is provided, which comprises a laundry drum and designed as an electric motor drive. The indoor unit is preferably used in a washing machine, in a spin dryer, in a tumble dryer or in a laundry cleaning machine. The drive axis of rotation about which the laundry drum rotates during operation, is lying, standing or inclined, in particular at a 45 ° angle to a flat surface, arranged. The power transmission of electric motor to the axis of rotation of the laundry drum is advantageously carried out via a direct drive or an intermediate transmission gear with transmission belt, or the like. According to the invention, at least one vibration sensor is provided, which in its entirety is rigidly or substantially rigidly coupled to the internal unit.

In other words, the vibration sensor or parts thereof are not carried in the drive rotation of the laundry drum. The inventive construction has the advantage that a mechanically particularly störunanfällige sensors for receiving the oscillatory movements is formed.

In a preferred embodiment, the vibration sensor is designed as an electronic sensor, in particular as an acceleration sensor. The measuring principle of the sensor is based in particular on capacitive, inductive or piezoelectric effects. This design of the vibration sensor means that all mechanical components - if present at all - are insulated within a sensor housing relative to the environment and the vibration sensor is very insensitive to external mechanical and / or chemical influences. Suitable vibration sensors are z. From the company Star Micronics (New Jersey, USA) under the designations ACA302 (3-axis capacitive sensor) or APA 304 (3-axis piezo-ceramic sensor).

In an expedient development of the invention, the internal unit comprises a printed circuit board on which the sensor is arranged as a printed circuit board module. This development is based on the idea of using cost-effective PCB mountable sensors. Such a circuit board is rigidly or substantially rigidly coupled to the vibration system "internal unit". Preferably, the circuit board is coupled to a washing tub, which is part of the internal assembly, alternatively, the circuit board is fixed, for example, on and / or on the electric motor.

Preferably, the circuit board fulfills a dual function and is at the same time designed as a motor control board, which preferably includes one or more power switches and / or a controller of the engine electronics, preferably designed as a microcontroller or DSP or CPU, for controlling, in particular for speed control of the electric motor. This embodiment has the particular advantage that the signal paths between the vibration sensor and the controller are very short and thus immune to interference and, for example, realized as strip conductors. Another advantage is the combination of the Motor control and the vibration sensor on a common circuit board in that the controller in a simple way the measured values of the vibration sensor and at the same feed and measured variables of the electric motor are supplied and in this way the basis for an optimal motion control of the electric motor is created.

In a preferred embodiment of the invention, the vibration sensor is realized and / or arranged such that rotational oscillatory movements of the internal assembly can be detected around a first axis of rotation. Preferably, the position of the first axis of rotation is arranged obliquely to the drive axis of rotation of the laundry drum, in particular so that there is an angle not equal to 0 ° between the first axis of rotation and the drive axis of rotation. Alternatively, the first axis of rotation and the axis of rotation of the drive can also be arranged skewed relative to one another, i. obliquely to each other, with imaginary extensions of the axes do not intersect. As a result of these refinements, rotational oscillatory movements are detected by the vibration sensor which contain a component which is independent of the rotational oscillatory movement about the drive rotational axis.

In a particularly preferred embodiment, the first axis of rotation is perpendicular or substantially perpendicular to the drive axis of rotation, so that a component of the rotational oscillatory motion is measured, which is independent of the rotational oscillatory movement about the drive axis of rotation. Here, the most critical to be regarded rotary oscillatory movements about axes perpendicular to the bearing or rotation axis of the drum - also referred to as pitching and yawing - - detected and thus recognized. For example, in a washing machine with a lying laundry drum, the yaw motions at increased amplitude for striking the tub and thus the internal unit of the washing machine on the side wall, while pitching movements can lead to striking the front of the washing machine. Accordingly, if at least one of these oscillatory motions is detected separately or additionally about an axis of rotation orthogonal to the drive axis of rotation, imbalances can be determined comparatively precisely and comparatively precisely controlled in response to the detected unbalance speed changes for a safe and effective operation of the laundry machine.

In a further development of the invention, a further vibration sensor, in particular a tachogenerator, as is known from the prior art, is additionally provided for measuring the rotary oscillatory movement about the drive axis of rotation of the laundry drum.

The invention is based on the consideration that a particularly reliable detection of the oscillatory movement of the internal unit of a laundry treatment machine can be achieved if, in addition to a reflected in the directly detectable speed change oscillatory motion about the axis of rotation and a swinging movement is detected by at least one further axis, which does not coincide with the drive rotation axis defined by the bearing shaft of the engine or the laundry drum. Thus, it is recognized that the laundry drum not only turns around this axis of rotation defined by its bearing axis, but also follows, depending on the position and the size of the unbalanced load, oscillatory movements in or about the axes orthogonal to the axis of rotation relative to a Cartesian coordinate system with axis of rotation lying on the x-axis represent the y- and z-axis.

In a further or alternative embodiment, the vibration sensor is realized and arranged such that rotational oscillatory movements about a second or a second and a third and a third axis of rotation are detectable. In particular, it is provided that the detection of the rotary rotational movements about two or three axes of rotation is effected by a single vibration sensor component. Alternatively or additionally, the vibration sensor is designed to detect linear oscillatory movements in up to three independent spatial directions.

In a preferred embodiment of the invention it is provided that the one or more sensors or oscillation sensors are connected to the controller. In particular, the internal unit is designed in terms of programming technology and / or circuit technology in such a way that the measured values of the sensors or vibration sensors are taken into account with regard to the control of the electric motor in terms of control technology and / or control engineering.

The object underlying the invention is further achieved by a method for controlling a laundry treatment machine according to the features of claim 13.

In this method, it is provided that the oscillatory movements of an internal unit of the laundry treatment machine are measured by one or more sensors. The internal unit comprises at least one laundry drum and a drive of the laundry drum designed as an electric motor. At least one of the measuring sensors is designed as an electronic sensor which is rigidly or substantially rigidly coupled in its entirety to the internal unit. As already explained above, the sensor is not carried along with the drive rotation movement of the laundry drum, but only with the vibrations of the internal unit. The measured values of the oscillation movement are transmitted to a controller, which can be used as a microcontroller or the like. is trained. The controller evaluates the measured values of the sensor (s) in real time and - also in real time - controls the electric motor as a function of the evaluated measured values. The inventive method offers substantially the same advantages as the device according to the invention according to claims 1 to 12.

mit:

S_max:

max. Auslenkung des Schwingungssensors am Motor und damit des Innenaggregats

f:

Trommeldrehfrequenz

a_{max_w}:

max. Beschleunigungswert des Schwingungssensors bei der Trommeldrehfrequenz f

In a preferred embodiment of the method, it is provided that, in addition to the measured value of the rotational oscillatory movement of the internal unit, the controller is also supplied with a current speed value-in the form of an actual and / or desired value-and a reference variable for the vibration deflection on the basis of these values of the aggregate is calculated. In the case of vibrating systems - assuming a harmonic vibration course - the following calculation formula is used, for example: $$S_{\mathrm{Max}}\alpha a_{\mathrm{Max}.w}/{\left(2\pi f\right)}^2$$

With:

S _max :

Max. Deflection of the vibration sensor on the engine and thus of the internal unit

f:

Drum rotational frequency

a _{max_w} :

Max. Acceleration value of the vibration sensor at the drum rotation frequency f

In an expedient development of the method is provided that also motor feed sizes, motor current, voltage, position signals o.ä. be considered in the evaluation of the measured values. In particular, it is provided that an internal unit according to one of claims 1 to 12 is used for the method.

The problem underlying the invention is finally solved by the use of an electronic sensor as a vibration sensor in an internal unit according to one of claims 1 to 12.

In a further development of the invention, the rotary oscillatory movement about the drive axis of rotation of the laundry drum is measured from the feed quantities for the motor or the speed fluctuations of the same.

Figur 1

eine rückseitige Ansicht einer Waschmaschine in schematischer Darstellung.

An embodiment of the invention will be explained in more detail with reference to a drawing. Showing:

FIG. 1

a rear view of a washing machine in a schematic representation.

FIG. 1 schematically shows a washing machine in an end view against the rear side of a machine housing 1 of the washing machine, wherein the rear side shown faces a loading opening (not shown) of the washing machine. In the machine housing 1, an inner unit 2 is suspended vibratory.

The inner unit 2 comprises a lye tub 3, a washing or laundry drum 4, a Trommelriemenrad 5, a transmission belt 6, a Motorriemenrad 7 and an electric motor 8. In other words, the inner unit comprises all the components with the rotating washing or laundry drum 4 a form a common vibration system, which is vibration-isolated and / or-damped by a suspension relative to the machine housing 1.

The drum-shaped Laugenbottich 3 is aligned in its longitudinal extent parallel to the bottom of the machine housing 1, that is arranged in the machine housing 1 lying. A first side wall of the tub Laugenbottichs 3 facing the loading opening, not shown. Above the schematic representation of the washing machine in Figure 1, a rectangular coordinate system 4 is drawn with three axes, wherein the axis marked X is aligned parallel to the longitudinal extent of the tub Laugenbottichs 3.

The washing or laundry drum 4 is arranged concentrically within the tub Laugenbottichs 3 and is in particular in the rear wall of the Laugenbottichs 3 - ie in the loading opening facing away from the second side wall of the Laugenbottichs 3 - rotatably mounted.

The washing or laundry drum 4 is rotatably connected to the Trommelriemenrad 5, which is arranged concentrically to the washing or laundry drum 4, but smaller in diameter than the washing or laundry drum 4 is formed. The Trommelriemenrad 5 is disposed on the side of the second side wall outside of the tub Lye 3. About the transmission belt 6, the drum pulley 5 is coupled to a motor pulley 7, which is arranged offset parallel to the drum pulley 5, but offset in the direction of the bottom of the machine housing 1. The motor pulley 7 is rotatably connected to the output shaft of the electric motor 8, so that the motor pulley 7 is driven by the electric motor 8. About the belt transmission consisting of the Motorriemenrad 7, the transmission belt 6 and the Trommelriemenrad 5, the washing or laundry drum 4 is rotated within the tub Lye 3 in rotation. In an alternative embodiment, the washing or laundry drum 4 is moved by a direct drive, wherein the direct drive is located at the location of the drum belt 5.

On the electric motor 8, an engine electronics 10, for example in the form of a planar or 3-D printed circuit board is provided, which is rigidly connected to the electric motor. The engine electronics 10 includes the power output stage for energizing the electric motor 8, a vibration sensor for receiving vibrations of the indoor unit and a controller for detecting the measured values the vibration sensor and for controlling the electric motor. The vibration sensor is designed such that it can measure rotations about the axes of the coordinate system 9 denoted by Y and / or Z and / or the angular accelerations associated with these rotations, ie in particular pitching movements of the internal assembly 2 (about the Y-axis) and / or yawing movements of the internal unit 2 (about the Z-axis). In addition, the vibration sensor can be designed such that vibrations are also registered about the X axis.

The suspension of the inner unit 2 is realized in the ceiling region of the machine housing 1 by springs 11, which engage in each case with its one end in the ceiling-side corner regions of the machine housing 1 and with its other end to four different positions on the indoor unit 2, here at the top of Laugenbottichs 3, are attached. Further, the inner assembly 2 is supported by four friction damper 12 in the bottom portion of the machine housing 1, wherein the friction damper 12 are each supported with one end in the corner regions of the machine housing 1. The respective other end is attached to the bottom of the machine housing 1 side facing the inner unit 2, here at the bottom of the tub Laugenbottichs 3, at four different positions.

LIST OF REFERENCE NUMBERS

1

machine housing

2

indoor unit

3

wash tub

4

Washing or laundry drum

5

Trommelriemenrad

6

transmission belt

7

Motorriemenrad

8th

electric motor

9

coordinate system

10

engine electronics

11

feathers

12

friction damper

Claims (17)

Vibrationally suspended internal unit (2) of a laundry treatment machine which comprises a laundry drum (4) and a drive of the laundry drum (4) designed as an electric motor (8),
characterized,
in that at least one vibration sensor is provided, which in its entirety is rigidly or substantially rigidly coupled to the internal unit (2). Inner unit (2) according to claim 1,
characterized,
is formed in that the vibration sensor as an electronic sensor, in particular acceleration sensor. Inner unit (2) according to claim 2,
characterized,
is that the vibration sensor formed as a capacitive-use of effects and / or inductive effects and / or piezoelectric effects based measuring principle. Inner unit (2) according to one of the preceding claims,
marked
by a printed circuit board, wherein the vibration sensor is designed as a printed circuit board module on the printed circuit board (10). Inner unit (2) according to one of the preceding claims,
characterized,
that the vibration sensor to the electric motor (8) and / or with a washing tub (3) of the indoor unit coupled, directly or indirectly, in particular via the circuit board, rigid. Inner unit (2) according to claim 4 or 5,
characterized,
that the circuit board as a motor control board is formed (10), which preferably has a circuit breaker and / or a controller for controlling, in particular rotation speed control, the electric motor (8). Inner unit (2) according to one of the preceding claims,
characterized,
that the vibration sensor is arranged so constructed and / or in or on the indoor unit that rotary vibratory movements of the internal unit (2) are detectable around a first axis of rotation (X, Y, Z). Inner unit (2) according to claim 7,
characterized,
in that the first axis of rotation (Y, Z)) is arranged obliquely, in particular perpendicularly or substantially perpendicularly, to a drive rotational axis defined by the bearing shaft of the motor (8) and / or the laundry drum (4). Inner unit (2) according to one of the preceding claims,
characterized,
is provided that a further sensor, in particular a tachometer generator for measuring the rotary vibratory movement about the drive rotational axis (X). Inner unit (2) according to one of the preceding claims,
characterized,
in that the vibration sensor is designed and / or arranged in or on the inner assembly such that rotational oscillatory movements of the inner assembly are detectable about a second axis of rotation (X, Y, Z) and / or a third axis of rotation (X, Y, Z) Rotary axes (X, Y, Z) are arranged obliquely to each other, in particular perpendicular or substantially perpendicular to each other. Inner unit (2) according to one of the preceding claims,
characterized,
in that the vibration sensor is designed and / or arranged in or on the inner assembly such that linear oscillatory movements of the inner assembly along a first (X, Y, Z) and / or a second (X, Y, Z) and / or a third spatial direction ( X, Y, Z) are detectable. Inner unit (2) according to one of the preceding claims,
characterized,
in that the vibration sensor or sensors are connected to the controller for transferring the measured values of the vibration sensor (s) to the controller. Method for controlling a laundry treatment machine, wherein the oscillatory movements of an internal unit (2) of the laundry treatment machine comprising a laundry drum (4) and an electric motor (8) drive the laundry drum (4) are measured with one or more sensors and at least one of Sensor is designed as an electronic sensor which is rigidly or substantially rigidly coupled in its entirety with the inner unit (2), wherein the measured values are transmitted to a controller and wherein the controller evaluates the measured values of the sensor or sensors in real time and the electric motor (8) depending on the evaluated measured values. The method of claim 13, wherein the controller evaluates the current speed of the laundry drum (4), preferably by the controller from the current speed and the one or more measured values of the oscillating movement of the internal unit (2) the oscillation deflection of the indoor unit (2) or a proportional thereto Value calculated. The method of claim 13 or 14, wherein the controller additionally receives motor feed sizes and the control of the electric motor on the basis of a coupled evaluation of the motor feed and the measured values of the sensor or sensors. Method according to one of claims 13 to 15, characterized in that an internal unit (2) according to one of claims 1 to 12 is used. Use of an electronic sensor as a vibration sensor in an internal unit (2) according to one of Claims 1 to 12, preferably in a method according to one of Claims 13 to 16.

Images