JP2007120384A - Hybrid type construction machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To secure safety by accurately notifying an operator of load condition replacing engine noise in both of a series and a parallel system and issuing an appropriate warning corresponding to a working condition in the series system. <P>SOLUTION: In a hybrid type construction machine driving a generator 2 by an engine 1, charging a battery device 3 by output of the generator 2 and compensating shortage of engine output to work load by the battery device 3, workload is determined by a controller 12 from DC voltage and DC current detected by both of a voltage and a current meters 13, 14, and pseudo-engine noise which is load information according to magnitude of work load instead of engine noise is displayed toward an operator by a display device 17. Also, alarm sound is issued to workers around the machine from the display device 17 during no engine operation in which work is done by only accumulated electric power of the battery device 3. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a hybrid construction machine that uses both engine power and power stored in a power storage device.

  Hybrid construction machines are divided into a series system and a parallel system depending on how the engine power and power storage are used.

  4 and 5 simply show the configuration of the drive system and the control system in both systems.

  In the series system, as shown in FIG. 4, the generator 1 is driven by the engine 1, and the power storage device 3 is charged by the power generated by the generator, and the motor 4 is driven by the power generator 2 and the power storage device 3. The hydraulic pump 5 is driven by the electric motor 4.

  The hydraulic pump 5 is connected to a hydraulic actuator (for example, in the case of an excavator, a boom, an arm, a bucket cylinder, a left / right traveling hydraulic motor, etc.) via a control valve 6, and is supplied from the hydraulic pump 5. These hydraulic actuators are driven by the pressure oil.

  On the other hand, in the parallel system, as shown in FIG. 5, the generator 1 and the motor function are performed by the hydraulic pump 5 and one unit via the power distribution device (power divider, sometimes referred to as PTO) 7 to the engine 1. The generator motor 8 to be performed is connected in parallel, and these are simultaneously driven by the engine 1.

  In such a hybrid system, the engine 1 is stably operated in the high efficiency region, the shortage of the engine output with respect to the work load is compensated by the power storage device 3, and the surplus power is generated by the generator 2 or the generator motor 8 to generate power. It is intended to perform energy-saving operation by storing electricity in the battery.

  Specifically, in the series method, when the work load is large, in addition to the generated power, the electric motor 4 is driven by the discharged power from the power storage device 3, and when the work load is small, the surplus generated power is stored. The device 3 stores electricity.

  Further, when the work load is equal to or less than the set value (light load) and the charge amount of the power storage device 3 is equal to or greater than the set value (large charge amount), the engine 1 is stopped. To drive.

  On the other hand, in the parallel system, when the work load is large, the generator motor 8 is made to act as a motor by the stored power of the power storage device 3 to supplement the engine output. When the required power is small, the generator motor is generated by the surplus of the engine output. The power storage device 3 is charged by causing the power generator 8 to perform a generator action.

Among such hybrid systems, a parallel system is disclosed in Patent Document 1, for example.
JP 2004-150305 A

  In a normal hydraulic excavator that does not employ a hybrid system, the engine sound changes according to the size of the work load, and the load is estimated by the operator listening to the engine sound and fed back to the operation. For example, if it is estimated that the load is large, an operation for reducing the load is performed.

  Also, surrounding workers recognize that the machine is operating by the engine sound and pay attention.

  That is, in the construction machine, the engine sound is important information for operation and safety for the operator and surrounding workers.

  However, in the hybrid system, both the series and parallel systems are basically configured to compensate for the shortage of engine output with the power storage device, so the engine sound changes regardless of changes in workload during hybrid work. No change in engine sound. That is, work information such as engine sound is not transmitted to the operator.

  For this reason, it becomes impossible to estimate the load, so the conventional method of feeding back the engine sound to the operation cannot be taken, and the illusion that the load is light or the machine itself is not powerful, etc. In this respect, the operability is poor.

  On the other hand, in the series system, when the predetermined engine stop condition (light load and large charge amount) is established as described above, the engine automatically stops and automatically performs engine-free work only by the power storage device power storage. Because it shifts, there is no engine sound.

  For this reason, since surrounding workers may not be aware that the machine is operating, there is a problem in terms of safety.

  By the way, Patent Document 1 discloses a technique for protecting surrounding workers from a machine.

  In this known technique, in the parallel system, the engine is automatically stopped at the lever neutral from the viewpoint of energy saving, and the engine is restarted when the lever is operated, and on this assumption, an alarm is issued at the lever neutral, The surrounding workers are alerted to “the machine starts to move when the lever is operated”.

  Here, the alarm is issued only when the lever is neutral, and the alarm is not issued when the lever is operated, because the engine always operates when the lever is operated, and the worker can recognize that the machine is operating by the engine sound.

  However, with the series system, the normal construction machine and parallel system are called “no engine work” where the engine stops when a certain stop condition is set regardless of lever operation, and the machine moves by the stored power even when the engine is stopped. Because there is a special condition that does not exist in the hybrid construction machine that takes it, it is not possible to ensure the safety of workers if a known technique that does not give an alarm during lever operation is diverted.

  In other words, in the series system, although it is dangerous for the operator to operate the lever without moving the engine sound, the known technology cannot cope with this point. On the contrary, it becomes dangerous.

  As described above, in the conventional hybrid construction machine, it means that the work is being performed, and the information of the engine sound indicating the size of the work load is not transmitted to the operator or surrounding workers, or is not accurately transmitted. An inherent problem was happening based.

  Therefore, the present invention provides a hybrid construction machine capable of accurately transmitting load information in place of engine sound to an operator in both series and parallel systems.

  The present invention also provides a hybrid construction machine capable of ensuring safety by issuing an appropriate alarm according to a work state in a series system.

  The invention of claim 1 comprises an engine, a generator driven by the engine, and a power storage device charged by the output of the power generator, and the power storage device compensates for a shortage of engine output with respect to the work load. In the hybrid construction machine configured to generate power with the generator by the surplus and store in the power storage device, the workload is detected by the load detection means, and the magnitude of the detected workload is detected by the display means. The load information corresponding to is displayed for the operator instead of the engine sound.

  According to a second aspect of the present invention, in the configuration of the first aspect, the display means is configured to emit a sound corresponding to the magnitude of the work load as a pseudo engine sound.

  According to a third aspect of the present invention, in the configuration of the first aspect, the display means is configured to turn on or blink an indicator lamp having a color corresponding to the size of the work load.

  According to a fourth aspect of the present invention, a generator is driven by an engine and an electric motor is driven by the output of the generator to operate an actuator, while surplus power is stored in a power storage device, and a predetermined engine stop condition is satisfied. In the hybrid construction machine configured so that the engine can be stopped and the engineless operation can be performed only by the power stored in the power storage device, a warning is generated by the display means when the engine stop condition is satisfied. Is.

  According to a fifth aspect of the present invention, in the configuration of the fourth aspect, the display means is configured to emit an alarm sound.

  According to a sixth aspect of the present invention, in the configuration of the fourth or fifth aspect, the work load and the charge amount of the power storage device are detected, and the engine is stopped when the work load is less than the set value and the charge amount is greater than the set value. It is configured to shift to an engine-free working state.

  A seventh aspect of the present invention is the configuration according to any one of the first to sixth aspects, further comprising selection means for selecting activation / deactivation of the display means.

  According to the present invention, it is possible to solve an inherent problem based on the fact that the engine sound is not transmitted to the operator or surrounding workers, or is not transmitted accurately, and to improve safety or operability.

  That is, according to the first to third aspects of the present invention, load information corresponding to the detected work load is displayed to the operator instead of the engine sound. It is possible to make use of the technique that is normally used in construction machinery, which estimates the size and feeds back to the operation. Moreover, there is no possibility of falling into the illusion that the load is light or the machine itself is not powerful. In these respects, operability can be improved.

  In particular, according to the second aspect of the present invention, a pseudo engine sound that follows the engine sound is generated, so that there is less discomfort than a normal machine, and load information can be accurately grasped compared to visual display of characters, light, etc. In addition, the operability is further improved because it does not interfere with the operation.

  By the way, when working at night or when working in a residential area or the vicinity in the daytime, displaying the load information with sound may cause a noise problem.

  In this regard, according to the third aspect of the invention, the load information is displayed by lighting or blinking the work indicator lamp of a color corresponding to the magnitude of the work load (for example, the three color lamps are sequentially lit or blinked according to the load). Therefore, the noise problem can be cleared.

  The display using the pseudo engine sound and the display using the work indicator lamp may be arbitrarily selected according to the work environment.

  On the other hand, according to the inventions of claims 4 to 6, in the series system, when the engine stop condition is satisfied (in claim 6, when the work load is less than the set value and the charge amount is more than the set value), an alarm is issued. Since it is configured, it is possible to alert a surrounding worker by issuing an alarm even during a lever operation in which the machine moves without an engine sound. For this reason, a worker's safety can be improved.

  In this case, by issuing an alarm sound as in the invention of claim 5, the alarm effect is enhanced and the safety is further improved.

  Further, according to the invention of claim 7, since the operation of the display means can be selected by the selection means, for example, when load information is not particularly required in the inventions of claims 1-3, the inventions of claims 4-6 In this case, display / non-display can be arbitrarily selected according to the necessity of display and the desire of the operator.

  An embodiment of the present invention will be described with reference to FIGS.

First embodiment (see FIGS. 1 and 2)
In the first embodiment, a series system is adopted.

  In addition, in 1st Embodiment and 2nd Embodiment mentioned later, the same code | symbol is attached | subjected and shown to the part shown in FIG.4, 5, and the duplication description is abbreviate | omitted.

  In the series system, the output of the generator 2 is sent to the power storage device 3 via the generator controller 9 as shown in FIG.

  Further, the generator output and the output of the power storage device 3 are sent to the electric motor 4 via the electric motor controller 10, whereby the electric motor 4 rotates and the hydraulic pump 5 is driven.

  The charge amount of the power storage device 3 is detected by the charge state management device 11 and sent to the controller 12.

  In addition to the charge amount, the controller 12 includes a DC voltage and a DC current detected by a voltage sensor 13 and a current sensor 14 provided in a DC circuit connecting the generator controller 9 and the motor controller 10, and a generator voltage. Are input, and based on the input information, the operation / stop and rotation speed commands of the engine 1 to the governor 15 and the generator current command to the generator controller 9 are output.

  On the other hand, a lever operation detector 16 for detecting a lever operation amount is connected to the electric motor controller 10, and the operation / stop and rotation speed of the electric motor 4 (discharge amount of the hydraulic pump 5 = actuator speed) are controlled according to the lever operation amount. Is done.

  In this embodiment, a display device 17 is connected to the controller 12.

  The display device 17 includes a sounding body that emits a sound such as a buzzer or a chime. Based on the command signals I and II from the controller 12, an alarm or load information is sent from the display device 17 to the operator and surrounding workers. As a sound is emitted.

  This will be specifically described with reference to FIG.

  (i) When the work load is obtained from the DC voltage and direct current information by the controller 12, the work load is not more than the set value A (light load), and the charge amount is not less than the set value B (large charge amount). Regardless of the lever operation, the engine 1 is stopped and the engine 4 enters the non-engine working state in which the electric motor 4 is driven only by the stored power.

  FIG. 2 illustrates a case where the engine operation state is entered because the charge amount exceeds the set value B while keeping the work load at or below the set value A. Conversely, the charge amount is set to the set value B. Even when the work load drops from the set value A or more to the following while maintaining the above, the engine-less work state is entered. A set value C for the charge amount of the power storage device in FIG. 2 indicates a set value at which the engine 1 is restarted.

  At the same time when the engine-free operation state is entered, a command signal I is sent from the controller 12 to the display device 17. Based on the command signal I, the display device 17 enters the engine-free operation state, that is, “engine An alarm sound (for example, intermittent chime sound or buzzer sound) is generated saying that the machine is operating without sound.

  With this alarm sound, it is possible to inform surrounding workers that the engine is not working and to call attention. For this reason, a worker's safety can be improved.

  (ii) During the work performed while the engine 1 is operating, a command signal II associated with the work load is output from the controller 12 to the display device 17, and the pseudo engine sound is output from the display device 17 based on the command signal II. Is emitted.

  FIG. 2 illustrates a case where a pseudo engine sound whose volume continuously changes in accordance with the increase or decrease of the load is shown, but in addition, a continuous sound that increases in height as the load increases, You may make it emit the intermittent sound etc. in which an interval becomes small according to an increase.

  With this pseudo engine sound, it is possible to make use of a technique taken by a normal construction machine in which an operator estimates the magnitude of the load and feeds back the operation. Moreover, there is no possibility of falling into the illusion that the load is light or the machine itself is not powerful. In these respects, operability can be improved.

  In particular, because it is a sound display, there is less discomfort for operators accustomed to estimating the load with sound (engine sound), and it is easier to grasp load information accurately than visual display methods such as letters and light The operability is further improved because it does not interfere with the operation.

  Note that the alarm sound and the pseudo engine sound may be output from different sound generators, or may be generated as separate sounds that can be identified from the same sound generator.

  On the other hand, when the load information is not particularly required or when there is no worker to be alerted in the surroundings, the pseudo engine sound or the alarm sound may be wasted and may be distracted.

  Therefore, in this embodiment, as shown in FIG. 1, a selection means (for example, a switch) 18 is connected to the controller 12, and one or both of the command signals I and II are sent from the controller 12 to the display device 17 by the selection means 18. The operator can arbitrarily select whether to output one or both of an alarm sound during non-engine work and a pseudo engine sound during normal work from the display device 17.

Second embodiment (see FIG. 3)
In the second embodiment, a parallel system is adopted. Only differences from the first embodiment will be described.

  In the parallel system, the power storage device 3 is connected to the generator motor 8 via the inverter / converter 19, and charging / discharging of the power storage device 3 is controlled according to whether the generator output of the generator motor 8 is excessive or insufficient.

  Further, the inverter / converter 19 performs switching between the generator operation of the generator motor 8 and the motor operation, control of the generated power (the number of revolutions of the generator motor 8), torque control of the generator motor 8 based on a command from the controller 12, and the like. Do.

  In the case of the parallel system, the engine 1 is always operated during the operation as described above, and there is no engine-free operation state unlike the series system of the first embodiment.

  Therefore, in the second embodiment, a command signal associated with the work load from the controller 12 to the display device 17 according to the work load detected by the voltage and current sensors 13 and 14 during normal work (the command of the first embodiment). The display device 17 is configured to generate only a pseudo engine sound corresponding to the work load.

  Thereby, also in the parallel system, the operability can be improved in that the operator can estimate the magnitude of the load and reflect it in the operation, as in the first embodiment.

  By the way, it is desirable from the viewpoint of display effect that the alarm when the engine stop condition is satisfied and the load information according to the size of the work load are displayed as sound as in the above two embodiments. Even in the daytime, when working in a residential area or in the vicinity thereof, such as when working in a work environment where quietness is required, sound may cause a noise problem.

  Therefore, other display methods may be used in place of the sound display.

  For example, in the first embodiment, as an alarm when the engine stop condition is satisfied, an alarm lamp may be turned on or blinked by the display device 17 as indicated by a broken line in FIG.

  On the other hand, in both the first and second embodiments, as a display method of load information, as shown by a broken line in FIGS. It may be made to blink (as a specific example, the three color lights are sequentially turned on or blinked according to the load).

  Furthermore, display by sound and display by warning light or indicator light may be arbitrarily selected according to the work environment.

  Alternatively, depending on the work environment, sound display and other displays may be used in combination in order to further enhance the display effect.

  The warning light or indicator light may be installed in the cab or outside the machine. Alternatively, it may be installed both in the cab and outside the machine.

  When the indicator lamp is installed in the cab, the load level on the display may be changed, for example, the height of the bar graph may be changed according to the load.

It is a block diagram which shows the structure of the drive system and control system of the hybrid type construction machine concerning 1st Embodiment of this invention. It is a time chart for demonstrating the effect | action of 1st Embodiment. It is a block diagram which shows the structure of the drive system and control system of the hybrid type construction machine concerning 2nd Embodiment of this invention. It is a block diagram which shows simply the structure of the drive system of a series system in a hybrid type construction machine, and a control system. It is a block diagram which shows simply the structure of the drive system and control system of the parallel system.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Engine 2 Generator 3 Power storage device 4 Electric motor 5 Hydraulic pump 7 Power distribution device 8 Generator motor 11 Charging state management device constituting charge amount detection means 12 Controller 13 Voltage sensor constituting load detection means 14 Current sensor 17 Display device 18 Selection means

Claims (7)

  An engine, a generator driven by the engine, and a power storage device charged by the output of the generator; the power storage device compensates for a shortage of engine output relative to a work load; In the hybrid construction machine configured to generate electric power and store in the power storage device, the load detecting means detects the work load, and the display means displays the load information corresponding to the detected work load in the engine. A hybrid construction machine configured to display to an operator instead of sound.   2. The hybrid construction machine according to claim 1, wherein the display means is configured to emit a sound corresponding to the magnitude of the work load as a pseudo engine sound.   2. The hybrid construction machine according to claim 1, wherein the display means is configured to turn on or blink an indicator lamp having a color corresponding to a work load.   The generator is driven by the engine, and the motor is driven by the output of the generator to operate the actuator. On the other hand, the surplus power is stored in the power storage device, and the engine is stopped under a predetermined engine stop condition. A hybrid type construction machine configured to perform engine-free work only by the power storage of the apparatus, and configured to issue a warning by a display means when the engine stop condition is satisfied. Construction machinery.   The hybrid construction machine according to claim 4, wherein the display means is configured to emit an alarm sound.   It is configured to detect the work load and the charge amount of the power storage device, and to stop the engine and shift to a non-engine work state when the work load is less than the set value and the charge amount is more than the set value. The hybrid construction machine according to claim 4 or 5.   The hybrid construction machine according to any one of claims 1 to 6, further comprising selection means for selecting activation / deactivation of the display means.

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