Construction machine with presence recognition system

[0001] The invention relates to a construction machine according to the preamble of claim 1 or a presence control method according to claim 14.

[0002] In practice it is determined that the operator of the working machine enjoys a high degree of work safety. This is ensured when the operator is not exposed to the danger of injury, or is warned in time against a threatening danger.

[0003] Also, the working machine must be signaled in time when the operator is no longer able to take action or when he is no longer able to drive the working machine correctly. This happens when warning signals are sent to the operator to draw his attention to possible danger.

[0004] A safety device that is suitable for rail vehicles is a deadman switch. The traction vehicle driver must activate it at certain intervals to indicate to the system that it is still fresh. If this button pressure does not occur, then the system issues an optical or acoustic warning. If this warning is ignored by the driver, then the system assumes that the driver of the vehicle is no longer able to take action and automatically performs automatic forced braking to prevent misfortune.

[0005] In road construction, especially in finishing machines, seat contact switches are used which determine whether the driver's seat of the vehicle is occupied. If the seat contact switch is activated, the finisher assumes that the operator is in the driver's seat, so that all operating functions are available to the operator. In contrast, all functions are blocked when the seat contact switch opens. At the same time, it is problematic that even in the event of small movements or lifting of the operator from above the driver's seat, the seat contact switch opens and thus interrupts the operation of the finisher. Sudden stoppages of working functions, however, lead to dents in the road pavement or damage to the asphalt surface.

[0006] It is also a delicate matter that the seat contact switch, which is built into the finishing machines, triggers a busy signal not only for persons, but also when other objects are stored on the surface of the seat. The operator can thus pretend to be in the driver's seat on the finisher while he is in another position on the finisher. So there is no more reliable operator guide for the finishing machine.

[0007] For example, DE 37 11 677 C2 describes a seat contact switch that is built into the driver's seat. As soon as two spaced contact surfaces are squeezed, the vehicle receives a signal that the driver of the vehicle is legally occupying the driver's seat. However, the disadvantage is the use of numerous mechanical springs, which are particularly susceptible to wear.

[0008] JP 2 034 434 A discloses a construction machine that is shaped to detect the presence of an operator. To this end, a sensor is placed on the operator panel to detect the operator. In case of

ΕΡ 2 407 705 Β1 sensor comes ο photoelectric sensor, which is shaped as a light source and at the same time as a light receiver. If the sensor detects that the operator is no longer present on the control handle, the construction machine is shut down. The disadvantage of this is that the sensor, which is provided on the operator panel, is easily susceptible to dirt and moisture. It can also happen that the sensor is damaged in harsh operating conditions.

[0009] GB 2 462 580 A describes a safety system for operating a construction machine. The safety system basically consists of a warning device, a control unit and detection units, which are preferably mounted in a personnel safety helmet. If the detection unit is detected by the driver of the vehicle via a warning device, then the construction machine can be started, and thus separate working functions can be freely switched on.

[0010] GB 2 353 180 A describes the presence detection system for a construction machine. This system includes a sensor that is located on the driver's cab housing above the driver's seat. If the sensor detects a code, picked up by the operator in any form, at a predetermined distance, then the construction machine is ready for operation. Otherwise, the work machine shuts off.

In view of the state of the art presented at the heart of the invention is the task of providing a construction machine with the use of simple construction means that provides both an improved dimension of work safety and also contributes to an improved quality of road construction. The task is also to develop a method that is used to control the presence of the operator on a construction machine, without too much restriction on the free movement of the operator.

[0011] The task set is solved by the features of claim 1 or claim 14. Improved developments are given by the dependent claims.

The present invention relates to a construction machine, in particular a finishing machine, with an operator panel, a driver's seat or a standing work place for the operator and a presence detection system which includes a sensor that is shaped to detect whether the operator is present in the driver's seat or standing workplace. As described previously, the seat contact switches are used in practice, which are directly connected to the driver's seat and react to the driver's seat load. In contrast, the sensor of the presence detection system according to the invention is incorporated into the control panel of the construction machine. At the same time, the sensor monitors the presence of the operator in the driver's seat or in a standing work place, while it allows the operator to move slightly. In the case of the invention, it is not possible to bypass the sensor as would be possible in the case of a seat contact switch through an object on the driver's seat. Another technical advantage of the invention is that the sensor built into the control panel is well protected and insensitive to the unevenness of the road surface on which the finisher moves. In contrast, the seat contact switch reacts sensitively to up and down movement of the driver's seat.

[0013] In a targeted embodiment, the sensor is shaped for contactless detection of whether an operator is present. For non-contact presence detection, no components are mechanically deformed, as is usually the case with traditional seat contact switches. Thanks to non-contact measurement, you don't have to deal with wear phenomena.

ΕΡ 2 407 705 Β1 [0014] Preferably, the sensor is a capacitive sensor, an induction sensor, an ultrasonic tube sensor and an infrared sensor. These sensors can easily detect the legal presence of the operator, while they respond reliably to different sizes of the operator's body.

[0015] It is also advantageous if the presence detection system is shaped to detect, based on measuring the distance, whether an operator is present. This offers a reliable and technically improved alternative to weight-based detection of the presence of a known seat contact switch.

[0016] Preferably, the presence detection system defines an average area of ​​approval which lies between the driver's seat or a standing work place and the operator's panel. The average approval area creates a framework condition for the presence detection system, which goes hand in hand with its reliable commissioning.

[0017] In a further purposeful embodiment of the invention, the presence detection system is designed to horizontally move the admission area, depending on the position of the driver's seat. As a result, the presence detection system is adapted to the position of the seat or the size of the operator.

[0018] Preferably, the sensor is shaped to determine the distance between the sensor and the operator, the distance defining the starting value. Also, no components are subjected to mechanical stress.

[0019] To guarantee the reliable and reliable activation of the presence detection system, the presence detection system is shaped to detect if the starting value, determined by the sensor, falls within the admission area. Thus, at the beginning a simple intelligibility check is carried out to determine whether the operator has actually taken up the driver's seat or is at a standing workplace. [0020] Preferably, the presence detection system is further shaped to determine from the start value an even tolerance range near the start value. By means of the tolerance range, it can be prevented that the construction machine or the finishing machine will be rapidly stopped when the operator moves slightly.

[0021] In addition, the sensor may be shaped to detect if the operator is within the tolerance range. In contrast to the contact switch, in which there are only two operating states, namely closed or unclosed, the sensor thus offers the technical advantage of allowing operator movement within a certain range.

[0022] Operator safety is further improved when the presence detection system is configured to send warning messages to the operator when the operator approaches the tolerance range. This allows the operator to be called to the correct posture when sitting, which is necessary for the safe operation of the construction machine. [0023] The operator and other present associates can be protected from independent movement of the construction machine, when the presence detection system is shaped to stop the use of the construction machine when the operator will leave the tolerance range.

[0024] The subject of the invention is also a method for controlling the presence of an operator in the driver's seat or in a standing place of work of a construction machine, whereby the presence detection system is activated, which includes a sensor incorporated into the operator's panel, then

ΕΡ 2 407 705 Β1 measurement with a sensor to determine the distance between the operator and the sensor and finally it is checked whether the distance is within the tolerance range.

Preferably, the operator has all the functions of a construction machine at his disposal, as long as the distance set by the sensor lies within the tolerance range.

[0026] The method may also include a method for determining a starting value, the starting value reflecting the distance of the operator relative to the sensor. With the optional check that the starting value is within the average admission area, determined by the presence detection system, it can be initially determined whether the operator has correctly taken the driver's seat or whether he is standing correctly in the standing work place.

[0027] Thus, the invention offers in particular a technical advantage that slight operator movements, whether in the driver's seat or in a standing work place, do not lead to a sudden stop of the construction machine, but depending on the tolerance range, small operator movements are allowed. They may be absolutely necessary for reliable operation of a construction machine or a finishing machine and for an impeccable work result.

[0028] The subject of the invention is explained based on the drawings. And so they show:

figure 1 measurement of presence detection, represented by detection of the operator on the driver's seat, with a sensor incorporated in the operator's panel, and figure 2 schematic view to visualize the average area of ​​admission of the presence detection system, and figure 3 measurement of presence detection, shown at a standing work place of a construction machine.

[0029] Figure 1 shows an operator who sits in front of the operator panel 1 in a construction machine on the driver's seat 2. The control panel 1 has various control functions. In addition, in the figure

1 the presence detection system 3 is illustrated, which includes a sensor 4 incorporated into the operator panel

1. Through the lines, directed from the operator panel 1 towards the operator, the measurement of sensor 4 is shown, which is to check whether the operator is sitting in the driver's seat 2. In addition, figure 1 shows the starting value 5, which is measured by the sensor 4. The starting value 5 indicates the distance between the sensor 4 and the operator. Depending on the body size or operator's body circumference, the starting value is different 5. In addition, in Figure 1 the tolerance range 6 is shown. The tolerance range 6 is oriented according to the starting value 5 and extends uniformly from the starting value 5 in a positive or negative direction, i.e. looking to the right or left of the starting value 5. [0030 ] Figure 2 shows the control panel 1 and the driver's seat 2, with no operator sitting on the driver's seat 2. In addition, the average clearance area 7 is visible in figure 2. The average approval area 7 is the framework condition for activating the presence detection system 3. The presence detection system 3 can be started when the starting value 5 falls into the medium approval area 7.

[0031] Figure 3 shows an operator who stands in front of the operator panel 1 of a construction machine at a standing work place. In addition, the sensor 4 is visible, which is located in the operator panel 1 and is part of the presence detection system 3. Sensor 4 measures the distance from each other to the construction machine operator.

EP 2 407 705 Β1

In this case, the presence detection system 3 determines whether the operator is correctly standing in the standing workplace or whether the measured distance is within the tolerance range 6. If the sensor 4 measures the distance which is within the tolerance range 6, then the operator has all the available working functions of a construction machine. In contrast, the measured distance outside the tolerance range leads to the stop of all working functions, because the presence detection system 3 assumes that the operator has left the standing workplace.

[0032] When the ignition key is turned or the main travel switch is activated, the presence detection system 3 can be activated. Then the sensor 4 controls whether the operator is sitting in the driver's seat 2 or whether he is standing in a standing work place. If the starting value 5 is determined by the sensor 4, which falls within the medium approval area 7, the presence detection system 3 is activated. In order to offer the operator sufficient freedom of movement, but without allowing him to leave the driver's seat 2 or standing place of work, an approximate start value of 5 is determined in the range of tolerance 6. When operating a construction machine, sensor 4 measures the distance from each other to the operator. The presence detection system 3 compares the distance measured by the sensor 4 with the tolerance range 6 and checks whether the operator remains within the tolerance range 6 during the operation of the construction machine or the finishing machine. If this is the case, then the system 3 detects that the operator is positioned correctly in front of the operator panel on the driver's seat 2. As the operator moves, the distance measured by sensor 4 changes. If the presence detection system 3 finds that the measured distance is approaching the limit of tolerance 6, then an acoustic or optical signal is issued, which prompts the operator to take the place again in the driver's seat 2 or to position himself correctly in a standing workplace. However, if the distance measured by sensor 4 lies outside the tolerance range 6, then this means that the operator has left the driver's seat 2 or a standing workplace, after which all the functions of the construction machine are turned off.

[0033] Presence detection system 3 can also be used without problems in other construction machines that are operated by a standing operator. With the presence detection system 3, for example in the case of a shaker, it can be prevented that it continues working when the operator has left it. Thus, work safety can be increased, which reduces work injuries.

EP 2 407 705 Β1