JP2016052832A - forklift - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a forklift equipped with a theft detection system.SOLUTION: A rear axle 26 of a forklift is provided with rear wheels 21. When the forklift is towed in a theft, the resistance force that the rear wheels 21 receive from a ground plane changes so that the rear axle 26 oscillates. When the forklift is lifted by a crane in a theft, the rear wheels 21 are caused not to touch the ground so that the rear axle 26 oscillates by gravity force. Then, a controller receives the input from an oscillation angle sensor 28 for detecting the oscillation of the rear axle 26. Upon receipt of the input from the oscillation angle sensor 28 while recognizing the key-off and the on-state of a theft detection system, the controller executes the output to cause a rotary lamp to be actuated.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a forklift provided with a theft detection system.

  Conventionally, in order to suppress theft in an automobile, the development of a theft detection device as disclosed in Patent Document 1, for example, has been underway. In Patent Document 1, when it is determined that the car has been stolen and transferred while the main power is stopped, the position information acquisition means is operated to acquire the location information of the moving object and A theft detection device that can be transmitted to the public is disclosed.

Japanese Patent Laid-Open No. 2004-30043

  Against this background, it is desired to suppress theft even in forklifts. This invention is made | formed in view of the situation mentioned above, The objective is to provide the forklift provided with the theft detection system.

  A forklift that achieves the above object has a front wheel and a rear wheel, the rear wheel is installed on a movable member, and the movable member is displaced by a change in a drag force received from a ground contact surface of the rear wheel, while the rear wheel In a forklift that displaces by losing the drag received from the ground surface when the wheel stops touching, a detecting means for detecting the displacement of the movable member, a control device for receiving a detection result from the detecting means, and the control device are key-off And a notification means that operates when the control device receives an input from the detection means when recognizing that the theft detection system is on.

  According to this, when the vehicle is towed during theft, the drag that the rear wheel receives from the ground contact surface changes, and the movable member on which the rear wheel is installed is displaced. Further, the rear wheel is not grounded when the crane of the vehicle is lifted during theft, and the movable member is displaced by losing the drag from the ground surface. These displacements are detected by the detecting means even when the key is off. When the key-off and the theft detection system are on, the control device that has received the detection result can notify the outside that the theft has occurred by operating the notification means.

  In the forklift, the movable member is an axle provided to be swingable with respect to a machine base, the rear wheels are installed at both ends of the axle, and the detecting means is a swing for detecting the swing of the axle. A dynamic angle sensor may be used. According to this, since the axle can swing, if the rear wheel is insufficiently grounded, the swing of the forklift axle can be detected by the swing angle sensor.

  In the forklift, the rear wheel is a caster provided at a lower portion of the machine base, the movable member is a tilting member on which the caster is suspended, the detection means is provided on the tilting member, and the tilting member It is good also as a tilt angle sensor which detects the tilt with respect to the said machine base. According to this, when the caster is insufficiently grounded, the tilting member hangs down and the tilting angle sensor can detect the tilting.

  In the forklift, the control device may be connected to a main power source and a sub power source, and the control device may connect to the sub power source when detecting the interruption of the main power source. According to this, even if the main power supply is shut off for the purpose of theft, the theft detection function is not lost.

  In the forklift, the forklift may include a switching unit capable of switching on and off of the theft detection system. According to this, the worker can arbitrarily switch the theft detection system on and off.

  According to the present invention, the forklift can be provided with a theft detection system.

The side view which showed the whole counterweight type forklift. Schematic diagram of the rear axle of a counterweight type forklift. The block diagram which showed the input / output from a controller. The flowchart which showed the control flow of the controller. The side view which showed the whole reach type forklift. Schematic diagram of caster arm part of reach type forklift. The image figure which showed the communication state of an external management system and a forklift.

(First embodiment)
Hereinafter, a first embodiment embodying a forklift will be described with reference to FIGS. Here, when specifying the front-rear, left-right, up-down directions, the front means the direction in which the worker on the forklift is facing during the cargo handling operation. More specifically, the direction from the worker on board to the direction in which the fork is located is defined as the front. The rear is the opposite direction from the front as seen by the operator. Left and right means left and right with the operator facing forward. The top and bottom are defined as the head side is up and the foot side is down when the operator is on the forklift.

  A counterweight type forklift 10 shown in FIG. 1 (hereinafter simply referred to as a counterweight forklift 10) has a machine base 11. A driver seat 12 is provided on the upper part of the machine base 11. A steering wheel 13 is provided in front of the driver seat 12. A mast 15 is provided in front of the steering wheel 13. A fork 17 installed on the mast 15 is moved up and down by a lift cylinder 16. An instrument panel 14 provided at the lower portion of the steering wheel 13 is provided as a part of the machine base 11. A head guard 18 is provided above the driver seat 12. A rotating lamp 19 is provided on the top of the head guard 18. A pair of left and right front wheels 20 and a pair of left and right rear wheels 21 are provided at the bottom of the machine base 11. The front wheel 20 is supported by the axle and is provided in front of the lower part of the machine base 11. The rear wheel 21 is supported on the axle and is provided at the lower rear of the machine base 11. Here, the front wheel 20 plays the role of a drive wheel. On the other hand, the rear wheel 21 serves as a steered wheel. A controller 22 serving as a control device is provided inside the machine base 11. Further, a main power supply 24 and a sub power supply 25 are provided inside the machine base 11. During work, the main power supply 24 supplies energy to the counterweight forklift 10.

  The axle of the rear wheel 21 will be described with reference to FIG. The machine base 11 is provided with a rear axle beam 26 (hereinafter simply referred to as the rear axle 26) as an axle for supporting the pair of left and right rear wheels 21. The rear axle 26 supports the rear wheel 21 at both ends. The pair of left and right rear wheels 21 receive the vertical drag from the ground contact surface to maintain the balance and support the vehicle weight. The rear axle 26 has a center pin 27 that serves as a support point at the axial center of the rear axle 26. The rear axle 26 is a swinging member that can swing in the vehicle width direction of the machine base 11 around the center pin 27.

  The rear axle 26 is provided with a swing angle sensor 28 as detection means. The swing angle sensor 28 is provided from the rear axle 26 via the link member 29 and detects the swing of the rear axle 26. The swing angle sensor 28 shown here may simply detect an inclination or measure an actual angle, and any sensor may be used as long as it can detect the swing. The swing angle sensor 28 detects a swing of the machine base 11 caused by unevenness of the ground when the counterweight forklift 10 is used. The swing angle sensor 28 inputs the detection result to the controller 22. When the controller 22 receives an input from the swing angle sensor 28, the controller 22 performs swing control of the rear axle 26 to improve running stability.

  As shown in FIG. 3, the controller 22 is connected to the instrument panel 14, the angle sensor 30, the hydraulic sensor 31, the travel sensor 32, the operation output unit 33, the notification unit 34, the key 36, the main power supply 24, and the sub power supply 25. Electrically connected. The instrument panel 14 includes a display 14A and switches 14B. The instrument panel 14 can display characters and the like on the display 14 </ b> A by the output from the controller 22. The instrument panel 14 can input the operation result to the controller 22 by operating the switches 14B. The angle sensor 30 refers to a sensor capable of detecting displacement including the swing angle sensor 28. When the angle sensor 30 detects the displacement of the displacement detection target, the angle sensor 30 inputs the detection result to the controller 22. The hydraulic sensor 31 detects the oil pressure on the hydraulic circuit. When the oil pressure sensor 31 detects a change in oil pressure, the oil pressure sensor 31 inputs a detection result to the controller 22. The travel sensor 32 is a sensor mounted on a vehicle that detects vehicle speed, wheel rotation, and the like. The traveling sensor 32 of this embodiment inputs a detection result to the controller 22 when detecting a change in the vehicle speed. The operation output unit 33 performs operations such as running, stopping, turning, and cargo handling. The operation output unit 33 includes, for example, an engine, a mission, a rack and gear, a hydraulic pump, a hydraulic circuit, and the like. The operation output unit 33 receives an output from the controller 22. Conversely, information from the operation output unit 33 is input to the controller 22. The information from the operation output unit 33 includes, for example, the engine speed. The notification unit 34 includes a revolving light 19, an alarm device, and an external communication device. In the present embodiment, the rotating lamp 19 is used as the notification means. The notification unit 34 receives an output from the controller 22. The key 36 switches between key-on (the key is turned on) and key-off (the key is turned off). The key 36 inputs an operation result to the controller 22 by an operator's operation. The controller is electrically connected to the main power supply 24 and the sub power supply 25, and measures the voltage of each power supply.

  The control process of the controller 22 that detects theft will be described with reference to FIG. First, in step S10, the controller 22 determines whether the theft detection mode is on or off, and further determines whether the counterweight forklift 10 is in a key-off state. If the condition that the theft detection mode is on and the key off is not satisfied in step S10, the process proceeds to step S20B. Here, the case where the condition that the theft detection mode is on and the key-off is not satisfied is, for example, a state where the counterweight forklift 10 is used in the factory, or the counterweight forklift 10 is stopped with the theft detection mode turned off. It is assumed that In step S20B, the detection result from the swing angle sensor 28 is input to the controller 22. Then, the control flow of the controller 22 proceeds to step S30B, and the controller 22 determines that the swing of the rear axle 26 is not due to unauthorized movement.

  Hereinafter, a case where the condition that the theft detection mode is on and the key is off in step S10 will be described. When the condition that the theft detection mode is on and the key is off is satisfied in step S10, the process proceeds to step S20A. In step S20A, when the swing angle sensor 28 detects the swing of the rear axle 26, the detection result is input to the controller 22. Then, the control flow of the controller 22 proceeds to step S30A, and the controller 22 determines that the swing of the rear axle 26 is due to unauthorized movement based on the input detection result. Then, the control flow of the controller 22 proceeds to step S40, and the controller 22 outputs an operation command to the notification means. In this embodiment, since the notification means is the revolving lamp 19, the controller 22 issues a command for turning on and rotating the revolving lamp 19 to the revolving lamp 19. Then, the control flow of the controller 22 proceeds to step S50, and the controller 22 issues an operation restriction command to the operation output unit 33. The operation restriction includes, for example, prohibiting engine start or performing ECU control so that acceleration cannot be performed. A series of control processes of the controller 22 is completed by the control flow described above.

  In the present embodiment, the theft detection mode can be switched on and off by a switching unit provided in the machine base 11. The switching unit is, for example, a display 14A or switches 14B provided in the instrument panel 14. The operator can arbitrarily switch the theft detection mode on and off by operating the display 14A and the switches 14B.

The effect | action by the said structure is demonstrated below. In the following description, it is assumed that the counterweight forklift 10 is in the theft detection mode and in the key-off state.
According to such a configuration, when the counterweight forklift 10 is stolen by towing, the balance of the vertical drag received by the left and right rear wheels 21 against the unevenness of the ground is lost. Then, the rear axle 26 swings to maintain the left and right balance. As a result, since the swing angle sensor 28 is provided via the rear axle 26 and the link member 29, the swing of the rear axle 26 is immediately detected. Since the swing angle sensor 28 is electrically connected to the controller 22, the detection result is immediately input to the controller 22. Receiving the input, the controller 22 operates the revolving light 19 as a notification means, assuming that the unauthorized movement has been performed. The revolving light 19 emits a warning light that informs the counterweight forklift 10 about the theft of the counterweight forklift 10 about the theft.

  Further, when the counterweight forklift 10 is stolen by lifting with a crane or the like, the rear wheel 21 does not receive vertical drag due to grounding. Then, the rear axle 26 is tilted toward one of the left and right rear wheels 21 around the center pin 27 by gravity. As a result, the swing angle sensor 28 immediately inputs the detection result to the controller 22. The subsequent control flow is the same as that for theft by towing, and is therefore omitted.

  Further, the controller 22 measures the voltage of the main power supply 24, and switches the energy supply source to the sub power supply 25 when the voltage of the main power supply 24 suddenly drops, for example, by shutting off the main power supply for the purpose of theft.

According to the embodiment described above in detail, the following effects are obtained.
(1) The rear axle 26 as a movable member provided with the rear wheel 21 swings when the contact between the rear wheel 21 of the counterweight forklift 10 and the ground contact surface is insufficient. The swing angle sensor 28 detects the swing of the rear axle 26 and inputs the detection result to the controller 22. In response to this, the controller 22 activates the rotating lamp 19 which is a notification means under the condition that the theft detection mode is on and the key is off. The revolving light 19 can notify the counterweight forklift 10 that the theft has been performed.

  (2) The rear axle 26 is provided for improving the stability when the vehicle travels, and has good response to the unevenness of the ground contact surface. Therefore, when the vehicle is towed during theft, the swing of the rear axle 26 in the vehicle width direction can be accurately detected by the swing angle sensor 28.

  (3) The rear axle 26 can swing even in the case where the vehicle itself moves in parallel, such as crane lifting. Crane lifting is sometimes used as a technique that prevents the angle sensor from reacting by lifting the vehicle in parallel during theft. However, in the present embodiment, the rear axle 26 is a member that can swing independently regardless of the inclination of the entire vehicle, so that it is possible to detect unauthorized movement at the same time that the rear wheel 21 leaves the contact surface.

  (4) The rear axle 26 as a movable member is mounted on the counterweight forklift 10. Therefore, a theft detection system can be introduced into the counterweight forklift 10 without additionally mounting a movable member.

  (5) Since the swing angle sensor 28 is originally mounted on the rear axle 26, a theft detection system can be introduced simply by rewriting the program of the controller 22.

(6) Since the auxiliary power supply 25 is provided, the function of the theft detection system is not lost even if the main power supply 24 is shut off for the purpose of theft.
(7) The operator can arbitrarily switch the theft detection mode on and off. Therefore, the theft detection mode can be turned off when the operator wants to move the vehicle in the key-off state for some reason including maintenance.

(Second embodiment)
A second embodiment will be described with reference to FIG. In addition, about the structure which is common in the said embodiment, description of the said embodiment is used and a code | symbol is used in common.

  The reach-type forklift 50 (hereinafter simply referred to as reach forklift 50) is provided with a machine base 51, and the machine base 51 is provided with a standing operation unit 52. A drive steering wheel 53 serving both as a drive and a steering is provided at the left rear of the lower part of the machine base 51. Further, a caster 54 as a driven wheel is provided at the right rear of the lower part of the machine base 51. Further, a mast 57 is provided in front of the machine base 51. A reach leg 58 is provided below the mast 57. A pair of left and right front wheels 59 are installed in the lower part of the reach leg 58. A steering wheel 55 and an instrument panel 56 are provided on the upper part of the machine base 51. Further, a controller 60 is provided inside the machine base 51. An alarm device 61 is provided as a notification means inside the machine base 51 and is connected to the controller 60.

  The right rear part of the lower part of the machine base 51 provided with the casters 54 will be described with reference to FIG. A lower link 62 is connected to the machine base 51. The lower link 62 moves together with the machine base 51. The lower link 62 is a member having a shape extending in the vehicle width direction of the machine base 51. Further, the lower link 62 is connected to the shaft 63. The shaft 63 is connected to the lower link 62 and the caster link 64. The caster link 64 is a member that can tilt with the shaft 63 as a support point, and the caster link 64 is suspended. The lower link 62 and the caster link 64 are connected to the elastic member 65, respectively. The elastic member 65 presses the lower link 62 and the caster link 64, respectively. That is, the elastic member 65 urges the caster link 64 in a direction away from the lower link 62. When the reach forklift 50 is stopped, the vertical drag that the caster 54 receives from the ground contact surface and the force that the elastic member 65 presses the caster 54 against the ground contact surface via the caster link 64 are balanced. The caster link 64 is provided with a tilt angle sensor 66 as detection means for detecting the tilt of the caster link. The tilt angle sensor 66 shown here may simply detect the tilt or measure the actual angle, and any sensor can be used as long as it can detect the tilt.

  The input / output to / from the controller 60 is the same as the input / output to / from the controller 22 of the first embodiment, and the control process of the controller 60 is the same as the control process of the controller 22 of the first embodiment, and is therefore omitted.

The effect | action by the said structure is demonstrated below. In the following description, it is assumed that the reach forklift 50 is in the theft detection mode and in the key-off state.
According to this configuration, when the reach forklift 50 is stolen due to traction, the elastic member 65 expands and contracts against the change in the drag force caused by the unevenness of the ground, and tries to maintain the balance. The caster link 64 tilts as the elastic member 65 expands and contracts. Then, the tilt angle sensor 66 provided on the caster link 64 detects the tilt of the caster link 64 and inputs the detection result to the controller 60. Receiving the input, the controller 60 sounds an alarm 61 as a notification means, assuming that an illegal movement has been performed. The alarm device 61 informs by sound that a theft has occurred around the reach forklift 50 about to be stolen.

  Further, when the reach forklift 50 is stolen by lifting with a crane or the like, the caster 54 is not grounded. Since the caster link 64 does not receive a drag force from the ground contact surface unless the caster 54 is grounded, the caster link 64 hangs down below the machine base 51 by the urging force of the elastic member 65. As a result, the tilt angle sensor 66 immediately inputs the detection result to the controller 60. The subsequent control flow is the same as that for theft by towing, and is therefore omitted.

  Further, as in the first embodiment, the controller 60 measures the voltage of the main power supply 24. If the voltage of the main power supply 24 suddenly drops due to power supply for theft, the energy supply source is changed to the sub power supply 25. Switch to.

  According to this embodiment explained in full detail above, in addition to the same effect as (4), (6), (7) in 1st embodiment, there exist the following effects. In the first embodiment, the counterweight forklift 10 is replaced with the reach forklift 50, the swing angle sensor 28 is replaced with the tilt angle sensor 66, and the rear axle 26 is replaced with the caster link 64 (4), (6), The same effect as (7) can be obtained.

  (8) The caster link 64 as a movable member provided with the casters 54 tilts when the contact between the casters 54 of the reach forklift 50 and the ground contact surface is insufficient. The tilt angle sensor 66 detects the tilt of the caster link 64 and inputs the detection result to the controller 60. In response to this, the controller 60 activates the alarm device 61 as a notification means under the condition that the theft detection mode is on and the key is off. The alarm device 61 can inform the reach of the reach forklift 50 that the theft has been performed.

  (9) Since the tilt of the caster link 64 is detected by the tilt angle sensor 66, the vertical displacement due to the unevenness of the ground can be accurately detected when the vehicle is towed during theft.

  (10) Even when the vehicle itself moves in parallel, such as when the crane is lifted at the time of theft, the caster link 64 hangs down below the machine base 51 due to the urging force of the elastic member 65. Can be detected.

(11) A theft detection system can be introduced simply by attaching the tilt angle sensor 66 and rewriting the program of the controller 60.
In addition, you may change the said embodiment as follows. Moreover, about the structure which is common in the said embodiment, description of the said embodiment is used and a code | symbol is used in common.

  In the lift cylinder 16 provided on the mast 15 in FIG. 1, a hydraulic sensor 31 shown in FIG. 3 is provided below the lift cylinder 16. When vibration is applied to the vehicle during theft, the hydraulic pressure in the hydraulic circuit changes, so that the hydraulic sensor 31 can detect the change in hydraulic pressure. Therefore, in addition to the angle sensor 30 of the above-described embodiment, the hydraulic sensor 31 may be employed as the detection unit. By using these together, the accuracy of theft detection can be improved.

  FIG. 7 shows a plurality of forklifts on which the controller 22 or the controller 60 is mounted. The controller 22 or the controller 60 is electrically connected to a communication device (corresponding to the notification unit 34) as notification means. The communication device includes a transmitter and a receiver, and can communicate with a management computer 80 outside the forklift. A system including a plurality of or one forklift and the management computer 80 is called a management system. Since the transmitter and the receiver are also connected to the management computer 80, mutual reception with the controller 22 or the controller 60 is possible.

  When receiving an input from the angle sensor 30, the controller 22 or the controller 60 outputs a detection result to the communication device. The communication device transmits the output information to the external management computer 80 by radio waves or the like. The controller 22 or the controller 60 may activate the rotating lamp 19 or the alarm device 61 simultaneously with transmission.

  By adopting such a configuration, not only the vicinity of the forklift but also an outside worker can be notified that the theft has been detected. The communication apparatus can transmit data other than the input from the angle sensor 30 as long as it is input to the controller 22 or the controller 60. That is, if the input from the engine in the operation output unit 33 is transmitted to the management computer 80, it is possible to list the operating states in a forklift factory or the like. Further, it becomes possible for the operator to switch on and off the forklift theft detection system at a remote place from the management computer 80.

  In the controller 22 or the controller 60, a step in which the controller determines the degree of abnormality may be newly provided between step S20A and step S30A in FIG. For example, if the amount of change of the angle sensor exceeds the threshold value, it is determined that there is an abnormality, and the process proceeds to step S30A. Alternatively, it may be determined that an abnormality occurs when the angle change has occurred more than a predetermined number of times within a predetermined time, and the process proceeds to step S30A. If not, a step may be newly provided that returns to step S20A.

  The forklift includes an internal rechargeable forklift provided with a charging device inside the machine base 11 or the machine base 51. The charging device of the internal rechargeable forklift is provided with an insertion port into which a charging plug is inserted. When the charging plug is inserted, the controller 22 or the controller 60 receives an input during charging.

  If a theft detection system is introduced to such a forklift, detection of unauthorized movement can be realized with a simpler configuration. That is, when charging is performed in a state where the theft detection mode is on and the key is off, it is possible to make the notification means work when the charging plug is removed. The act of removing the charging plug here corresponds to the detection of the displacement of the movable member in the embodiment.

  The sub power supply 25 may be integrated with the main power supply 24. Here, the term “integrated” includes incorporating the sub power source 25 in the main power source 24 or mounting a type of capacitor having a large capacity in the main power source 24.

  In the first embodiment, the notification means is the revolving light 19, but an alarm device may be used as the notification means, or the revolving light 19 and the alarm device may be used in combination. In the second embodiment, the notification means is the alarm device 61. However, the notification device may use a revolving light, or the alarm device 61 and the revolving light may be used in combination.

  In a forklift other than the counterweight forklift 10 and the reach forklift 50, the forklift having a movable member can have an angle sensor attached to the movable member. Thereby, the same effect as the above-mentioned embodiment can be obtained.

The rocking angle sensor 28 may be attached to the link member 29.
A sensor that detects expansion and contraction of the elastic member 65 provided in the movable member may be used as the detection means.
The detection accuracy of the angle sensor may be changed manually by operating the display 14A.

○ A separate movable member may be attached to the forklift.
The management system may include a portable terminal, and the state of the forklift may be referred to at a terminal registered by the management computer 80.

  DESCRIPTION OF SYMBOLS 10 ... Counterweight forklift, 14 ... Instrument panel, 19 ... Revolving light as a notification means, 20 ... Front wheel, 21 ... Rear wheel, 22, 60 ... Controller as control apparatus, 24 ... Main power supply, 25 ... Sub power supply, 26: Rear axle as a movable member (axle), 28: Swing angle sensor as detection means, 54: Casters, 62: Caster link as movable member (tilting member), 66: Tilt angle sensor as detection means.

Claims (5)

Having a front wheel and a rear wheel, the rear wheel being installed on a movable member;
While the movable member is displaced by a change in drag received from the ground contact surface of the rear wheel,
In the forklift that loses the drag received from the contact surface and displaces when the rear wheel stops contacting,
Detecting means for detecting displacement of the movable member;
A control device for receiving a detection result from the detection means;
A notification means that operates when the control device receives an input from the detection means when the control device recognizes that the key-off and the theft detection system are on;
A forklift characterized by having. The movable member is an axle provided to be swingable with respect to the machine base;
The rear wheels are installed at both ends of the axle;
The forklift according to claim 1, wherein the detecting means is a swing angle sensor that detects the swing of the axle. The rear wheel is a caster provided at the lower part of the machine base,
The movable member is a tilting member on which the casters are suspended,
The forklift according to claim 1, wherein the detection unit is a tilt angle sensor that detects a tilt of the tilting member with respect to the machine base. The control device is connected to a main power source and a sub power source,
The forklift according to any one of claims 1 to 3, wherein when the control device detects the interruption of the main power source, the control device is connected to a sub power source.   The forklift according to any one of claims 1 to 4, wherein the forklift has a switching unit capable of switching on and off of the theft detection system.