Fire Hose Cart

Abstract

To provide a fire hose car for loading a fire hose and conveying the hose to a fire extinguishing work site, the fire hose car that can reduce a burden of an operator as the electric motor traveling and the electrically-powered assist traveling and the human power traveling can be selected, and also can prevent it from performing self-traveling arbitrarily when the operator is absent and performing the self-traveling against the intention of the operator, and therefore is highly safe.SOLUTION: A fire hose car is provided in which a tensile force detection unit detects tensile force, and when the pressure being more than a threshold value is applied in a pressure sensor, an electric motor provided in a wheel is controlled so as to be driven.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a fire hose carrier that loads a fire hose and transports the hose to a fire fighting work site. Specifically, the fire hose carrier has an electric motor built into its wheels and can travel by driving the electric motor. It is a highly safe fire hose carrier that will not move on its own when the operator is absent or against the operator's intention.

Background Art

[0002] A fire hose carrier is loaded on a fire truck with a hose and transported to the vicinity of a fire site, and then unloaded. Firefighters then tow and move it to the fire fighting work site.

[0003] The basic configuration of a fire hose carrier consists of a loading platform for loading a fire hose (hereinafter referred to as "hose"), wheels provided on the loading platform, and a tow handle provided in the traveling direction of the loading platform.

[0004] Generally, a fire hose carrier is made mainly of stainless steel or aluminum pipe materials and plate materials. Moreover, since the loaded hose is quite heavy, the total weight of the fire hose carrier and the hose is usually very heavy, at 150 - 200 kg.

[0005] Firefighters who are familiar with towing a fire hose carrier through training can travel to the fire fighting work site without problems on flat roads. However, when the fire site is at the end of a narrow road where a fire truck cannot pass and the distance from the position where the fire hose carrier is unloaded to the fire fighting work site is very long, or even if the distance is short but the fire fighting work site is on a hill or in the middle of a mountain and there is a continuous uphill road, no matter how experienced the firefighters are, the physical burden during traveling will be very large, and there is a risk of being late in arriving at the fire fighting work site.

[0006] In view of such circumstances, a fire hose carrier equipped with an electric motor and a battery has been proposed for a long time.

[0007] However, a fire hose car equipped with an electric motor and a battery may accidentally be kicked or hit by an object while waiting after lowering the hose or before being loaded onto a fire truck, which may cause the electric motor to drive unintentionally and the car to move forward on its own.

[0008] If a fire hose car weighing 150 - 200 kg moves forward on its own, it is very dangerous as it may collide with firefighters standing nearby or run over them.

[0009] Therefore, there is a need to develop a highly safe fire hose car that can prevent itself from moving forward on its own when the operator is absent or against the operator's intention.

Prior Art Documents

Patent Documents

[0010]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0011] Patent Document 1 discloses a fire hose layer comprising at least a pair of drive wheels, drive means for rotationally driving the drive wheels, a steering handle, a fire hose mounting portion, and a power supply device, and the fire hose layer travels at a predetermined speed by operating a throttle grip.

[0012] However, the fire hose layer described in Patent Document 1 may supply electricity to the drive means and move forward on its own when the steering handle is kicked or hit by an object during standby for fire fighting operations.

[0013] The inventors of the present invention regarded solving the above problems as a technical challenge. As a result of repeated trial and error in many trial productions and experiments, they came up with a remarkable idea that if the operator pulls the tow rope and then grasps the pressure sensor provided on the tow rope with a pressure equal to or higher than the threshold value, the electric motor built into the wheels will be driven, making it a fire hose car that will not move on its own when the operator is absent or against the operator's intention. Based on this idea, they advanced the research to materialize it and completed the present invention.

Means for Solving the Problems

[0014] The above technical problems can be solved by the present invention as follows.

[0015] The present invention is a fire hose car capable of selecting electric motor driving, electric assist driving, and manual driving. The fire hose car comprises a load platform that travels on one or two or more wheels and a tow rope provided on the load platform. The load platform is equipped with a battery and a control board for the electric motor. Each wheel is equipped with an electric motor controlled by the control board. The tow rope consists of a steering handle, a shaft provided with a pressure sensor, and a tensile force detection unit. The tensile force detection unit detects the tensile force, and when a pressure equal to or higher than the threshold value is applied to the pressure sensor, the electric motor provided on the wheels is controlled to drive.

[0016] Moreover, the present invention is the above-mentioned fire hose car in which the pressure sensor is provided on the lower surface of the shaft.

[0017] Moreover, the present invention is the above-mentioned fire hose car in which the threshold value is a pressure higher than the pressure generated by the weight applied to the tow rope.

[0018] Moreover, the present invention is the above-mentioned fire hose car in which the tensile force detection unit detects the tensile force based on the change amount of the distance that the shaft moves in the front-rear direction.

[0019] The present invention also relates to the above-described fire hose cart that drives the wheels with a predetermined driving force when the electric motor driving mode is selected.

[0020] The present invention also relates to the above-described fire hose cart that adjusts the driving force of the electric motor according to the magnitude of the detected tensile force to assist the running when the electric assist driving mode is selected.

Advantages of the Invention

[0021] The fire hose cart according to the present invention is a fire hose cart in which an electric motor is driven by a two-step operation in which an operator pulls a tow rope and holds a pressure sensor provided on the axis of the tow rope with a pressure equal to or higher than a threshold value.

[0022] Therefore, even when the electric motor driving mode or the electric assist driving mode is selected, it is possible to prevent the electric motor from being driven and running automatically when the operator is absent or running automatically against the intention of the operator, so it is a highly safe fire hose cart.

[0023] In addition, if a pressure sensor is provided on the lower surface (ground side) of the shaft, it becomes a fire hose cart that can naturally hold the pressure sensor.

[0024] In addition, by setting the threshold value to a pressure higher than the pressure generated when supporting the dead weight applied to the tow rope, it becomes a safer fire hose cart.

[0025] In addition, if the method of detecting the tensile force is based on the change amount of the distance that the shaft moves in the front-rear direction, the magnitude of the tensile force can be accurately detected.

[0026] The fire hose cart according to the present invention drives the wheels with a predetermined driving force when the electric motor driving mode is selected, and adjusts the driving force of the wheels according to the magnitude of the tensile force of the operator when the electric assist driving mode is selected, thereby reducing the running burden on the operator and being a highly safe fire hose cart.

Brief Description of the Drawings

[0027]

Figure 1

Figure 2

Figure 3

Embodiments for Carrying Out the Invention

[0028] The present invention is a fire hose cart that can select electric motor driving, electric assist driving, and manual driving.

[0029] Under the selection of electric motor driving, since the electric motor built into the wheels drives with a predetermined driving force and runs by itself, the operator can run the fire hose cart only by operating the steering wheel.

[0030] It is preferable that the driving force of the electric motor can be adjusted by the operator in two steps of high and low or steplessly between high and low.

[0031] This is because the fire hose cart can be run at the desired speed of the operator.

[0032] Under the selection of electric assist driving, the driving force of the electric motor built into the wheels is adjusted, and the electric motor can assist the running so that the pulling force of the operator remains constant whether on a flat road, an uphill road, or a mountain road.

[0033] In the fire hose cart in the present invention, when the tensile force detection unit detects a tensile force and the pressure sensor provided on the shaft detects a pressure equal to or higher than a threshold value, the electric motor is driven.

[0034] By setting that the electric motor is not driven unless the operator pulls the tow rope and holds the pressure sensor with a force equal to or higher than the threshold value, it is possible to prevent unauthorized self-running when the operator is absent or self-running contrary to the intention of the operator.

[0035] Note that under the selection of electric assist driving, the electric motor may be driven without the operator gripping the pressure sensor, if desired by the operator.

[0036] Under the selection of electric assist driving, as long as the tensile force does not continue, the driving of the electric motor does not continue either. Therefore, the risk is lower compared to under the selection of electric motor driving.

[0037] The fire hose carrier in the present invention is composed of a loading platform 1 capable of storing a fire hose and a handle 2 provided in the advancing direction of the loading platform.

[0038] The loading platform 1 is not particularly limited, and a loading platform similar to a known fire hose carrier can be used.

[0039] It is preferable to use square pipes (pipe materials) made of stainless steel (SUS304) and aluminum (A6063-T5) for the frame of the loading platform 1, and it is preferable to use a flat plate made of stainless steel (SUS304) for each panel.

[0040] The loading platform 1 is provided with one or more wheels. For the stability of the fire hose carrier, it is preferable to be provided with a pair of left and right wheels.

[0041] The wheel 3 is not particularly limited, but a non-puncture tire is preferable.

[0042] An electric motor is built into the wheel 3, and the driving of the electric motor is controlled by an electric motor control board provided on the loading platform.

[0043] The electric motor is not particularly limited, and a known electric motor can be used.

[0044] As an example of the electric motor, an in-wheel motor is exemplified.

[0045] The battery provided on the loading platform 1 can use a known battery, but a lithium battery is preferred.

[0046] The loading platform 1 is provided with a control board for the electric motor and a battery.

[0047] The control board for the electric motor and the battery are preferably provided outside the loading platform. This is to ensure the storage volume of the hose.

[0048] The handle 2 in the present invention is composed of a steering handle 4, a shaft 6 provided with a pressure sensor 5, and a tensile force detection unit 7.

[0049] The steering handle 4 is orthogonal to the shaft 6, and the operator can operate the steering handle 4 to control the fire hose car.

[0050] The steering handle 4 may be provided with a brake operation lever 8.

[0051] When the brake operation lever 8 is operated, a predetermined signal is sent to the electric motor control board, and the signal sent from the electronic speed controller (hereinafter referred to as "ESC") of the electric motor control board is forcibly stopped. The electric motor stops driving, the wheels 3 are in a free state, and can be physically stopped by a known disc brake.

[0052] (Detection of pressure) The shaft 6 constituting the handle 2 in the present invention is provided with a pressure sensor 5.

[0053] If a pressure sensor is provided on the steering handle, there is a risk of accidentally gripping the pressure sensor when pulling with the steering handle. If the pressure sensor is accidentally gripped and pulled, the electric motor will drive simultaneously when pulled. Therefore, under the selection of electric motor running, the fire hose car starts to run automatically against the operator's intention, which is dangerous.

[0054] The pressure sensor is preferably provided on the lower surface (ground side) of the shaft. This is because the fire hose cart has its center of gravity on the front side, and when it is on the lower surface, the pressure sensor can be naturally grasped.

[0055] The pressure sensor sets a threshold value to prevent malfunction.

[0056] The threshold value may be determined as desired. It may be the same value as the pressure generated to support the self-weight applied to the handle when the operator lifts the handle, or it may be a value of pressure greater than this pressure.

[0057] If the value of the pressure is set to be greater than the pressure generated to support the self-weight applied to the handle, it is possible to prevent the electric motor from being driven only by lifting the handle. Thus, the wheels can be prevented from being driven unless the operator intentionally grasps the pressure sensor.

[0058] Since the fire hose cart has its center of gravity in the front, the "self-weight applied to the handle" is the weight obtained by adding a part of the weight of the loading platform to the weight of the handle itself.

[0059] A known pressure sensor can be used as the pressure sensor.

[0060] Examples of the pressure sensor include a contact switch and a piezoresistive pressure sensor.

[0061] When a pressure equal to or greater than the threshold value is applied to the pressure sensor, a predetermined signal is transmitted to the electric motor control board.

[0062] (Detection of tensile force) The handle in the present invention is provided with a tensile force detection unit 7.

[0063] A contact type linear displacement sensor 71 is provided in the tensile force detection unit 7. Examples of the contact type linear displacement sensor include commercially available products (for example, "LP-10FBS-3" / manufactured by Midori Sokki Co., Ltd.) used for the control of various electric devices.

[0064] A description will be given with reference to FIG. 2 showing a state in which the towrope is being pulled by the operator in the traveling direction.

[0065] The shaft 6 can move back and forth by a distance of the effective stroke (L in FIG. 2).

[0066] When the operator pulls the towrope, the compression coil spring 74 contracts and the shaft 6 slides in the traveling direction by a distance corresponding to the tensile force, releasing the pressing on the tip of the contact type linear displacement sensor 71, and the tip of the contact type linear displacement sensor 71 extends by the compression coil spring 73 provided at the tip.

[0067] It is possible to detect that a tensile force is generated by the extension of the tip of the contact type linear displacement sensor 71, and it is also possible to detect the amount of force by which the towrope is pulled by the amount of extension of the tip.

[0068] When the tensile force detection unit 7 detects a tensile force, it transmits a predetermined signal to the electric motor control board.

[0069] It is preferable that the end face of the shaft 6 and the end face of the tip of the contact type linear displacement sensor 71 are always in contact via the compression coil spring 73 of the tip of the contact type linear displacement sensor 71 whether or not a tensile force is generated.

[0070] It is preferable to provide a shaft rotation restrictor 78 on the shaft 6. This is because by restricting the rotational movement, an accurate contact state between the end face of the shaft 6 and the end face of the tip of the contact type linear displacement sensor 71 can be maintained, and stable and accurate detection data can be obtained.

[0071] (Control mechanism of electric motor) The tensile force detection unit and the pressure sensor are connected to the electric motor control board. When the operator pulls the tow rope, a predetermined signal is transmitted from the tensile force detection unit to the control board of the electric motor. Also, when the operator grips the pressure sensor with a pressure equal to or greater than the threshold value, a predetermined signal is transmitted to the electric motor control unit.

[0072] While the pressure sensor is being gripped with a pressure equal to or greater than the threshold value, the electric motor control unit transmits a signal to the ESC and drives the electric motor with a constant output.

[0073] In the present invention, in case the power supply current value to the ESC on the electric motor control board rises above a certain value or drops below a certain value, the current detection sensor may detect the amount of current flowing through the electric motor and stop the transmission of the command signal of the ESC.

Embodiment

[0074] The embodiment was implemented according to the following specifications.

[0075] As the pressure sensor, a tape switch "OT-21BP-G" (manufactured by Osaka Automatic Electric Co., Ltd.) was used, and the threshold value was set to 3 N.

[0076] The pressure sensor was provided on the lower surface of the shaft.

[0077] For the contact type linear displacement sensor 71, "LP-10FBS-3" (effective stroke: 10 mm ± 0.5 mm, manufactured by Midori Sokki Co., Ltd.) was used, and the movable range (L) of the shaft 6 constituting the tow rope was set to 8 mm.

[0078] As the battery, a lithium battery "URB1270" (average voltage 25.6 V: 12.8 V × 2 (in series), capacity: 7.5 Ah) was used.

[0079] For the in-wheel motor built into the electric motor wheel 3, an in-wheel motor (specifications: 170 W / 24, torque = 10 N / m or more, KV value = 10.4, tire specifications: outer diameter 290 mm, width 90 mm, 6PR) was used.

[0080] (When the electric motor is running) Referring to FIGS. 2 and 3, when the tow bar is pulled by the operator in the traveling direction, the shaft 6 moves in the traveling direction, and the tip of the contact type linear displacement sensor 71 in contact with the rear end of the shaft 6 extends by the force of the compression coil spring 73.

[0081] When the tip of the contact type linear displacement sensor 71 extends, a predetermined signal is transmitted to the control board of the electric motor.

[0082] Also, when the operator grasps the pressure sensor 5 provided on the shaft 6 with a pressure equal to or higher than the threshold value, a predetermined signal is transmitted from the pressure sensor 5 to the control board of the electric motor.

[0083] When the control board of the electric motor receives the two predetermined signals of the tensile force and the pressure, it transmits a predetermined signal to the electric motor built in the wheel and drives the electric motor so as to reach the predetermined speed set by the operator.

[0084] (When the electric assist is running) Referring to FIGS. 2 and 3, when the tow bar is pulled by the operator in the traveling direction, the shaft 6 moves in the traveling direction, and the tip of the contact type linear displacement sensor 71 in contact with the rear end of the shaft 6 extends by the force of the compression coil spring 73.

[0085] When the tip of the contact type linear displacement sensor 71 extends, a predetermined signal is transmitted to the control board of the electric motor.

[0086] Also, when the operator grasps the pressure sensor 5 provided on the shaft 6 with a pressure equal to or higher than the threshold value, a predetermined signal is transmitted from the pressure sensor 5 to the control board of the electric motor.

[0087] When the electric motor control board receives the two predetermined signals of the tensile force and the pressure, it transmits a predetermined signal to the electric motor built in the wheel and drives the electric motor.

[0088] Further, the tensile force detection unit 7 transmits a voltage level signal corresponding to the amount of elongation at the tip of the contact type linear displacement sensor 71 to the electric motor control board, calculates the amount of tensile force applied to the towbar based on the transmitted voltage level signal, and transmits it as a speed command signal to the ESC. The ESC controls each in-wheel motor of the wheel 3 according to the transmitted speed command signal to adjust the driving force of the human power and the electric motor and assist in running.

Industrial Applicability

[0089] In the fire hose car according to the present invention, under the selection of electric motor driving, the wheels are driven with a predetermined driving force, and under the selection of electric assist driving, the driving force of the wheels is adjusted according to the magnitude of the tensile force of the operator. Therefore, the burden on the operator during running can be reduced. In addition, when the operator pulls the towbar and holds the pressure sensor provided on the towbar with a pressure equal to or higher than the threshold value, the electric motor built into the wheel is driven. Since the electric motor is driven only when the operator is pulling and operating the towbar, it is a highly safe fire hose car that can prevent the vehicle from running on its own when the operator is absent or running unintentionally according to the operator's intention. Therefore, the present invention is an invention with high industrial applicability.

Explanation of Signs

[0090] 1 Loading platform 2 Towbar 3 Wheel 4 Operating handle 5 Pressure sensor 6 Shaft 7 Tensile force detection unit 8 Brake operation lever 71 Contact type linear displacement sensor 73 Compression coil spring at the tip of the contact type linear displacement sensor 74 Compression coil spring 78 Shaft rotation restrictor

Claims

1. A fire hose cart capable of selecting electric motor driving, electric assist driving, and manual driving, wherein the fire hose cart comprises a platform driven by one or more wheels and a handle provided on the platform, the platform is provided with a battery and a control board for an electric motor, each of the wheels is provided with an electric motor controlled by the control board, the handle comprises a steering wheel, a shaft provided with a pressure sensor, and a tensile force detection unit, a fire hose cart in which the tensile force detection unit detects a tensile force, and when a pressure equal to or higher than a threshold value is applied to the pressure sensor, the electric motor provided on the wheel is controlled to drive.

2. The fire hose cart according to Claim 1, wherein the pressure sensor is provided on the lower surface of the shaft.

3. The fire hose cart according to Claim 1 or 2, wherein the threshold value is a pressure higher than the pressure generated by the dead weight applied to the handle.

4. The fire hose cart according to any one of Claims 1 to 3, wherein the tensile force detection unit detects a tensile force based on a change amount of the distance by which the shaft moves in the front-rear direction.

5. The fire hose cart according to any one of Claims 1 to 4, which drives the wheels to travel with a predetermined driving force under the selection of electric motor driving.

6. The fire hose cart according to any one of Claims 1 to 4, which assists traveling by adjusting the driving force of the electric motor according to the magnitude of the detected tensile force under the selection of electric assist driving.

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