JP5504249B2 - Hybrid rotary snowplow - Google Patents

Description

  The present invention relates to a rotary snowplow, and more particularly to a rotary snowplow employing a hybrid system.

In recent years, awareness of global environmental protection has increased, and the price of crude oil has soared, and hybrid passenger cars have been sold and gained popularity in the automobile field.
By the way, a rotary snowplow having a rotary snowplow attached to the front of the vehicle as a snowplow that removes snow on the road during winter snowfall is well known. It is disclosed. Conventional general rotary snowplows are equipped with diesel engines, but it is preferable that hybrids can also be realized in rotary snowplows for the purpose of efficient use of fossil fuels and reduction of carbon dioxide emissions. is there. Therefore, the present applicant has previously proposed a rotary snowplow adopting a hybrid system (Japanese Patent Application No. 2011-002956).

JP-A-6-81326

  In snow removal work with a rotary snowplow, the amount of snow and the state of snow often change depending on the location, and the snow removal load constantly fluctuates. In a conventional snow removal vehicle that drives a rotary snow removal device with power from an engine, when an overload operation is performed, the driver can easily detect it by a change in engine sound or the like.

  However, in a hybrid type snowplow that drives a rotary snow removal device with an electric motor, the electric motor has lower noise than the engine, and the sound and load of the engine are not linked, making it difficult to understand overload operation. There has been a problem that clogging (snow clogs in the blower and chute part of the snow removal device due to excessive snow removal load) has occurred.

  Although it is possible to check the decrease in the number of revolutions of the electric motor with instruments, in snow removal work with a rotary snowplow, the driver operates the steering wheel according to fluctuations in snow removal load, road surface conditions and surrounding traffic conditions, etc. The snow removal device must be controlled while adjusting the vehicle speed, and it is difficult to work while always checking the rotation speed of the electric motor with a meter.

  The present invention solves the above-described problems in a rotary snowplow adopting a hybrid system, and provides a hybrid rotary snowplow that can easily detect an overload operation and prevent a snow clog from occurring. Let it be an issue.

  According to the present invention, there is provided a hybrid system that includes a rotary snow removal device, outputs a power obtained by rotationally driving an electric motor with electric power generated by a generator driven by an engine, and In the hybrid type rotary snowplow that supplies the working power for driving the device and the driving power for running the vehicle from the hybrid system, the warning means notifies the operator while monitoring the driving load of the electric motor, and This is solved by reducing the vehicle speed by controlling the driving power.

  According to the rotary snowplow of the present invention, the driving load of the electric motor that outputs the power for running and snow removal work in the hybrid rotary snowplow is monitored, and when the load exceeds a predetermined value, warning means such as a buzzer is used. Since the operator is warned, overload operation can be detected easily and reliably even in a hybrid rotary snow plow that makes it difficult to understand overload operation, and snow clogging can be prevented in advance.

  According to the configuration of claim 2, since the vehicle speed is controlled to decrease when the driving load of the electric motor exceeds the second predetermined value, the vehicle speed is automatically adjusted before reaching the maximum load. Even an inexperienced operator can work without worrying about the snow removal load.

With the configuration of the third aspect, the vehicle speed can be automatically adjusted by appropriately controlling the hydraulic pump or hydraulic motor of the HST.
According to the configuration of the fourth aspect, it is possible to set an optimum load threshold value according to the location and time of snow removal work, environmental conditions such as temperature and humidity, snow accumulation amount and snow quality.

  According to the control method of the fifth aspect, the operator can easily and reliably detect an increase in the load, and the vehicle speed is automatically adjusted before reaching the maximum load. Therefore, even an inexperienced operator cares about the snow removal load. It is possible to work without having to do so.

  According to the control method of the sixth aspect, the vehicle speed can be automatically adjusted by appropriately controlling the hydraulic pump or hydraulic motor of the HST.

It is a schematic diagram which shows the structure of the drive system of the hybrid type rotary snowplow which concerns on this invention. It is a flowchart which shows the flow of the snow clog prevention control in embodiment. It is a block diagram which shows the structure which implements snow clogging prevention control.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a schematic diagram showing the configuration of a drive system of a hybrid rotary snowplow according to the present invention. As shown in the figure, the power generated by the hybrid system 10 that is a power generation source is transmitted to the work transmission 21 and the HST 30. The HST 30 is a continuously variable transmission using hydraulic pressure, at least one of which is composed of a variable displacement hydraulic pump 31 (HST pump) and a hydraulic motor 32 (HST motor), and controls the flow rate of the hydraulic pump or hydraulic motor. Control the running speed. Power from the HST 30 is transmitted to the front and rear wheels 43 and 44 through the front and rear differentials 41 and 42 via the traveling transmission 40.

  The working power for driving the rotary snow removal device reaches the transmission 22 from the work transmission 21 and is divided into two to drive the blower 23 and the other system drives the auger 25 via the chain transmission 24. A rotary snow removal device including an auger and a blower is the same as that conventionally known, and snow blown by the auger 25 and taken in from a chute (snow throwing cylinder) (not shown).

  The hybrid system 10 includes an engine 1 as a power source, a generator (generator) 2 driven by the engine 1, and a first inverter (inverter for generator) that converts AC power generated by the generator 2 into DC power. 3. Second inverter (motor drive inverter) 4 for converting DC power into AC power for motor drive, electric motor 5 for outputting working and traveling power, battery (storage battery) 6 for storing DC power, boosting mechanism As a step-up chopper 7 or the like. The step-up chopper 7 and the battery (storage battery) 6 are connected in series between the first and second inverters 3 and 4.

  The engine 1 can employ an appropriate prime mover such as diesel or gasoline. In the embodiment, a diesel engine having an output of 73 kW / 2000 rpm (385 N · m / 1600 rpm) is used. In the embodiment, the generator 2 having a rating of 75 kW / 380 V / 135 A is used. In the embodiment, the electric motor 5 having a rating of 55 kW / 380 V / 101 A is used.

  The rating of the battery 6 is 108V / 150Ah. The step-up chopper 7 has an input of 108 V / output of 600 V and a battery assist maximum of 50 kW. In the hybrid system, the battery is the most expensive device, and in this embodiment, a booster mechanism is provided to reduce the number (capacity) of the batteries to be mounted. The step-up chopper 7 used in the embodiment boosts the voltage 108V of the battery 6 to 600V.

  The hybrid system 10 of the present embodiment configured as described above is based on a series hybrid system, and the engine 1 is used only as a power source for the generator 2, and all the power for traveling and snow removal work is supplied to the electric motor 5. It is a full-fledged hybrid system that can only provide output. Since the engine 1 is used only as a power source for the generator 2, operation at a low load is possible, enabling efficient use of fuel and reduction of CO2 emissions.

  Now, as described above, in this embodiment, the entire power for running and snow removal is performed only by the output of the electric motor 5. Since the electric motor has low noise compared to the engine, it is difficult to understand overload operation and easily causes snow clogging. Therefore, in the present embodiment, the driving load of the electric motor 5 is monitored, and when the load becomes a predetermined value (threshold A) or more, the operator is notified by warning means such as a buzzer. Further, when the load further increases and the load becomes a second predetermined value (threshold value B) or more, the swash plate of the hydraulic pump 31 of the HST 30 (or the hydraulic motor 32 when controlling the flow rate of the hydraulic motor 32). The vehicle speed is decreased by controlling the tilt angle, and the rotational speed of the electric motor 5 is prevented from being dropped due to overload. By setting the second predetermined value (threshold value B) to a value close to the maximum load of the electric motor 5, the vehicle speed can be automatically adjusted immediately before the load reaches the maximum value.

  FIG. 2 is a flowchart showing the flow of snow clogging prevention control in the present embodiment. In this flowchart, the load of the electric motor 5 is monitored (S1), and when the motor load exceeds a predetermined value (threshold A), a warning buzzer is sounded to give a warning (S2). When the load further increases and exceeds the second predetermined value (threshold value B) (S3), the command value of the HST hydraulic pump 31 is changed. In the embodiment, the pump command value = current command value− (current electric motor load−threshold B) × proportional constant is set to reduce the vehicle speed and prevent the electric motor 5 from dropping. If the motor load is less than the threshold value B in S3, the process proceeds to S6, and the HST hydraulic pump 31 is controlled in a normal control routine. If the motor load is less than the threshold A in S1, the warning buzzer is stopped (S5).

FIG. 3 is a block diagram showing a configuration for performing the above-described snow clogging prevention control.
In the figure, a control device 50 is a control means 51 such as a CPU, a ROM 52 which is a storage means for storing a control program, threshold values (A, B), etc., and a storage means for storing a hydraulic pump command value and the like. It is comprised from RAM52 grade | etc.,. Information on the electric motor 5, the HST hydraulic pump 31 and the hydraulic motor 32 is input to the control device 50, and those control signals are output from the control device 50. The warning buzzer 60 is also turned on and off by the control device 50.

  Based on the load information input from the electric motor 5 to the control device 50, it is determined whether or not the motor load has reached the thresholds A and B as described above. The pump command value for controlling the HST hydraulic pump 31 is stored in the RAM 52. As described above, when the load of the electric motor 5 is equal to or higher than the threshold value B, the pump command value is updated and updated. The pump command value is sent from the control device 50 to the hydraulic pump 31.

  An appropriate method can be adopted as a method for monitoring the drive load of the electric motor 5. For example, there are a method for determining the load based on the motor rotation speed, a method for monitoring the drive current, and the like. In addition, a method for monitoring the driving voltage of the motor, a method for determining the load based on the electric power calculated based on the current and voltage, and the like can also be employed.

  The relationship between the threshold values A and B is A <B (the load set as the threshold value B is larger than the load set as the threshold value A) in terms of the magnitude of the load. However, the relationship between the thresholds A and B that are actually set varies depending on the load monitoring method. For example, in the case of the motor rotation speed, the rotation speed decreases as the load increases. Therefore, the relationship between the thresholds A and B is A> B (the rotation speed set as the threshold B is higher than the rotation speed set as the threshold A). Is smaller). Further, in the case of the drive current, since it is determined that the load increases as the current increases, the relationship between thresholds A and B is set as threshold B from the current value set as threshold A. Current value is larger).

  In this embodiment, a buzzer is used as a means for warning the operator when the motor load exceeds a predetermined value (threshold A). However, the warning means is not limited to a buzzer, and a warning lamp may be used. A buzzer and a lamp may be used in combination.

  Further, the thresholds A and B may be configured so that the operator can set them. In this case, the threshold values A and B may be stored in the RAM 52. What is necessary is just to comprise the threshold value setting, for example so that it may input from the operation panel etc. which were provided in the snowplow driver's seat. By adopting such a configuration, it is possible to set an optimum threshold value according to the location and time of snow removal work, environmental conditions such as temperature and humidity, the amount of snow and the snow quality.

  As described above, according to the rotary snowplow of this embodiment, the driving load of the electric motor 5 is monitored, and when the load exceeds a predetermined value (threshold value A), the warning means notifies the operator. Therefore, the operator can easily detect the situation where the load of the electric motor is likely to reach the maximum load, and by adjusting the vehicle speed to an appropriate vehicle speed, the occurrence of snow clogging can be prevented in advance. .

  When the load of the electric motor 5 further increases and becomes greater than or equal to the second predetermined value (threshold value B), the hydraulic pump 31 of the HST 30 (or the hydraulic motor 32 when controlling the flow rate of the hydraulic motor 32). ) Is controlled to reduce the vehicle speed and prevent the rotation speed of the electric motor 5 from dropping due to overload. That is, by automatically adjusting the vehicle speed immediately before the load of the electric motor reaches the maximum load, even an inexperienced operator can perform snow removal work without worrying about the snow removal load.

  Since the snow clog prevention control according to the present invention can be carried out only by the control method, it is possible to prevent the occurrence of snow clogs while minimizing the increase in cost as much as possible without requiring a configuration change or addition of equipment in the hybrid rotary snow plow. .

  As mentioned above, although this invention was demonstrated by the example of illustration, this invention is not limited to this. An appropriate method can be adopted as a method of monitoring the load of the electric motor. In addition, an appropriate system can be adopted as the hybrid system, and the system configuration can be changed as appropriate. As the configuration of the drive system of the snow removal vehicle, the configuration of the HST, and the configuration of the rotary snow removal device, appropriate ones can be adopted. Furthermore, the present invention can be applied not only to a rotary snowplow traveling on a road but also to a track snowplow that performs snow removal on a track.

1 Engine 2 Generator
5 Electric motor 10 Hybrid system 21 Work transmission 25 Auger 30 HST (hydraulic continuously variable transmission)
31 Hydraulic pump 32 Hydraulic motor 40 Traveling transmission 50 Control device 60 Warning buzzer (warning means)

Claims (6)

Equipped with a rotary snow removal device,
Equipped with a hybrid system that outputs the power obtained by rotating the electric motor with the electric power generated by the generator driven by the engine,
In the hybrid rotary snowplow that supplies the working power for driving the rotary snow removal device and the driving power for running the vehicle from the hybrid system,
A hybrid-type rotary comprising: load detection means for detecting a drive load of the electric motor of the hybrid system; and warning means for warning when the load detected by the load detection means exceeds a predetermined value. Snowplow.   2. The control unit according to claim 1, further comprising a control unit configured to control the vehicle speed to be decreased when a load detected by the load detection unit becomes equal to or greater than a second predetermined value larger than the predetermined value. Hybrid rotary snowplow. A hydraulic continuously variable transmission (HST) including at least one of a variable displacement hydraulic pump and a hydraulic motor, and configured to output driving power via the HST;
The control command value for the hydraulic pump or hydraulic motor of the HST is a value calculated by the following equation when the load detected by the load detection means is equal to or greater than the second predetermined value. 2. A hybrid rotary snowplow described in 2.

  4. The hybrid rotary snowplow according to claim 2, further comprising setting means for setting the predetermined value and the second predetermined value. Supplied from the hybrid system that outputs the power obtained by rotating the electric motor with the electric power generated by the generator driven by the engine, the working power for driving the rotary snow removal device and the driving power for running the vehicle In the control method of the hybrid rotary snowplow that
The driving load of the electric motor of the hybrid system is monitored, and when the driving load of the electric motor exceeds a predetermined value, a warning is given by a warning means, and the driving load of the electric motor is larger than the predetermined value. A control method for a hybrid rotary snowplow, wherein the vehicle speed is controlled to decrease when the vehicle speed exceeds a predetermined value. The traveling power is configured to be output via a hydraulic continuously variable transmission (HST), at least one of which includes a variable displacement hydraulic pump and a hydraulic motor,
6. The control command value of the hydraulic pump or hydraulic motor of the HST is a value calculated by the following formula when the driving load of the electric motor becomes equal to or greater than the second predetermined value. The hybrid rotary snowplow control method described.

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