GB2324377A

GB2324377A - Weight sensing module with correction for inclination

Info

Publication number: GB2324377A
Application number: GB9807512A
Authority: GB
Inventors: Peter Thierbach; Roman Romes
Original assignee: Robert Bosch GmbH
Current assignee: Robert Bosch GmbH
Priority date: 1997-04-15
Filing date: 1998-04-07
Publication date: 1998-10-21
Also published as: ITMI980686A1; FR2762087A1; IT1298986B1; GB9807512D0; DE19715590A1

Abstract

A sensor module has a first sensor (7) for detecting a weight magnitude on a processing machine and having an evaluating unit (6, fig. 2) to evaluate the signal of the first sensor (7). The first sensor (7) is preferably a pressure sensor, sensing the pressure in a hydraulic system, and is accommodated together with at least one additional position/inclination sensor (9,10) for detecting the position or inclination of a tractor hopper, for example, and with the evaluating unit (6), within the casing (2, fig. 1) of the sensor module (1). The output signal of the sensor module (1) is the weight magnitude on the processing machine is ascertained by evaluating the signals of each of the sensors and thus the signal is corrected for inclination.

Description

1 Sensor Module State of the Art 2324377 The invention relates to a sensor

module, in particular for a processing machine in agriculture or in road construction m connection with which a plurality of position data or weight data are to be capable of being detected, according to the generic portion of the main claim.

With known processing machines, in the case of vehicles for spreading fertiliser m agriculture for example, the amount of fertiliser applied has to be determined by weight measurement. Likewise the acceleration and the inclined position of the vehicle have to be ascertained in order to ensure uniform application of the spreading material on the surface.

The data to be detected are conventionally detected at various places on the vehicle and processed in a central evaluating and controlling instrument. With a view to calibration and for the purpose of setting the initial position of the vehicle, each mdividual sensor has to be calibrated and balanced prior to the start of processing.

Advantages of the Invention With the features according to the invention as specified in the characterising portion of the main claim a sensor module of the type described in the introduction is advantageous in that, as a result of the complex structural concept of the sensor module, production of the necessary sensors and their installation into the processing machine are considerably simplified.

In a preferred embodiment, in an agricultural vehicle for example, there are present within the sensor module two acceleration sensors, one for the inclination of the vehicle in the direction of travel and one for the inclination at 2 right angles to the direction of travel, and also a pressure sensor for measuring the hydraulic pressure on the hydraulic system. Measurement of the inclination is effected here _by way of detection of the acceleration, the output signal of the acceleration sensor being the product of the acceleration due to gravity and the sine of the angle of inclination and consequently the angle of inclination being directly proportional to the inclination, to be incorporated into the weighing process, of the implement in the terrain.

In particular, the sensor module according to the invention enables, in straightforward manner, distortions of measured values to be avoided in connection with the weighing of a spreading material to be applied with the vehicle that arise due to an inclination of the machine m relation to the horizontal at the time when the weight magnitude in respect of the material to be weighed is being derived. Since an electronic evaluating unit is directly present within the sensor module, data in respect of the spreading material to be applied that are purged of distortions due to changes in the position/inclination of the vehicle are available at the output of the sensor module.

Attachment of the sensor module to the appropriate parts of the vehicle is effected in advantageous manner in such a way that inclination errors, due to mounting, of a few degrees at the installation site can be eliniinated, also in the installed state on the vehicle, by means of a simple internal software compensation. As a result there is no longer any need to bring the sensor module exactly into a horizontal position at the installation site.

By virtue of a suitable design of a support part within the sensor module the individual sensors can be fixed directly with simple mounting steps. The evaluating unit which is likewise accommodated within the sensor module comprises both the electronics for evaluation of the pressuresensor signal and an electronic computer chip which, as mentioned above, supplies the value corresponding exactly to the mass to be weighed by utilising the signals of the inclination sensor. Furthermore, the computer chip may also supply control 3 signals that act on a system for appropriate metering of the spreading material to be applied.

Other advantageous flirther developments of the invention are specified in the subclaims.

Drawing An example of an embodiment of the sensor module according to the invention will be elucidated on the basis of the drawing. Illustrated are:

Figure 1: a view of a sensor module sealed with a casing; Figure 2: a first view of the inside of the sensor module, showing an evaluating unit and Figure 3: a second view of the inside of the sensor module, showing individual sensors.

Description of the Embodiment Example

In the example of an embodiment of a sensor module 1 according to Figure 1 a casing 2 is shown with a device 3 for attachment to a farm tractor, which is not represented here, by way of agricultural processing machine. Present on the casing 1 are a pressure port 4 for pressurising with the pressure of a hydraulic system and an electrical connector 5 for an analogue and/or digital signal output of the sensor module 1.

Shown in Figure 2 is the inside of the sensor module 1 with a view of an electronic evaluating device 6 and the location of a pressure sensor 7 by way of first sensor on a support part 8. The pressure port 4, which is not visible here, leads into the pressure sensor 7, it being possible in principle for a weight magnitude to be derived from the hydraulic pressure that is measured, for example at a storage container for a spreading material to be applied.

4 The view according to Figure 3 shows, for an assumed installation position with' a direction of travel of the vehicle in the y-direction, a first position/inclination sensor 9 for detecting the inclination m the direction of travel and a second position/inclination sensor 10 for detecting the inclination at right angles to the direction of travel, in the x-direction.

The electronic evaluating device 6 that can be seen in Figure 2 contains software-controlled electronic modules that digitise the possibly analogue signals of the individual sensors 7, 9 and 10 and link them together m such a way that m connection with the weighing of the spreading material to be applied with the vehicle, a measured-value distortion of the output signal of the pressure sensor 7 that arises due to an inclination of the vehicle in relation to the horizontal M the x- direction and also M the y-direction is eliminated.

Since the electronic evaluating unit 6 is likewise attached to the support part 8 with the individual sensors 7, 9 and 10 directly within the sensor module 1, the weight magnitudes in respect of the spreading material to be applied that are purged of distortions due to changes in the position of the vehicle are directly available at the connector 5.

The electronic evaluating unit 6 is flu-thermore provided with an electronic computer chip which can also make control signals available via the connector 5 that can act on an electromechanical system for appropriate metering of the material to be applied.

Claims

1. Sensor module, with - a sensor (7) for detecting a weight magnitude on a processing machine and with an evaluating unit (6) for the signal of the sensor (7), characterised in that - the first sensor (7) is accommodated, together with at least one additional position/inclination sensor (9, 10) for detecting the position of the processing machine and with the evaluating unit (6), within the casing (2) of the sensor module (1) and in that - an output signal of the sensor module (1) can be ascertained by evaluating all the signals of the sensors (7, 9, 10).

2. Sensor module according to Claun 1, characterised in that - the sensors (7, 9, 10) and the electronic evaluating device (6) are rigidly disposed on a common support part (8) within the casing (2) of the sensor module (1) and are capable of being calibrated prior to installation in the processing machine.

3. Sensor module according to Claim 1 or 2, characterised in that - the first sensor is a pressure sensor (7) with which a weight magnitude can be derived from a hydraulic pressure by incorporating the signals of the additional position/Mclination sensors (9, 10).

4. Sensor module according to one of the preceding claims, characterised in that - the additional position/inclination sensors (9, 10) are acceleration sensors with which, respectively, an inclination of the processing machine in a predetermined x-direction and/or y-direction can be derived from the acceleration values in 6 accordance with the folloWMg relationship: acceleration due to gravity sMe of the angle of inclination.

5. Sensor module according to one of the preceding claims, characterised in that - the evaluating unit (6) comprises an electronic computer chip for ascertaining control variables for the processing machine.

6. Sensor module according to one of the preceding claims, characterised m. that - the sensor module (1) is utilised for the purpose of measuring the weight of spreading material to be applied that is situated on an agricultural vehicle by way of processing machine.

7. A sensor module substantially as herein described with reference to the accompanying drawing.