Heaviness changing system

Abstract

To change heaviness of a pedal operation and a lever operation of a forklift truck or either of them in accordance with operation fatigue such as decrease in concentration.SOLUTION: A heaviness changing system S comprises a heaviness changing part 21, and an operation time storage part 303, and a change command part 309. The heaviness changing part 21 changes heaviness of a pedal 14 and a lever 15 of a forklift truck or either of them. The operation time storage part 303 stores continuous operation time. When the predetermined continuous operation time is reached, the change command part 309 controls the heaviness changing part 21 so as to change the heaviness of the pedal 14 and the lever 15 or either of them to second heaviness greater than first heaviness that is normal heaviness.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a weight change system for changing the weight of a pedal and a lever of a forklift or the weight of any one of them.

Background Art

[0002] Forklifts include types such as reach forklifts and counterbalanced forklifts. Forklifts are equipped with pedals and levers, and the number and functions thereof vary depending on the type of forklift.

[0003] As disclosed in Patent Document 1, a reach forklift is equipped with a brake pedal and a presence pedal. The presence pedal is configured to be able to stop traveling and cargo handling, and the driver cannot perform traveling and cargo handling unless the presence pedal is depressed. Further, as disclosed in Patent Document 2, a counterbalanced forklift is equipped with an accelerator pedal and a brake pedal, and an engine-type counterbalanced forklift is further equipped with a clutch pedal. Among battery-powered forklifts, an automatic forklift is further equipped with an inching pedal instead of a clutch pedal. By depressing the inching pedal, the driver can put the forklift in a semi-clutch state and cut off the driving power.

[0004] In addition, as disclosed in Patent Document 3, a reach-type forklift includes a lift lever for raising and lowering the forks, a tilt lever for changing the vertical angle of the forks, a reach lever for moving the lifting device forward and backward, and an accelerator lever for driving the forklift. Further, as disclosed in Patent Document 4, a counterbalanced forklift includes a tilt lever and an accelerator lever. Generally, as disclosed in Patent Document 5, a lever is configured to swing forward or backward from a neutral position and automatically return to the neutral position by a spring when not in operation. The invention disclosed in Patent Document 5 assists lever operation by an actuator when the operation amount of the operation lever exceeds a predetermined value in order to reduce the fatigue of the operator. In addition, for example, Patent Document 6 discloses a technique for assisting lever operation of a vehicle.

[0005] By the way, when it is desired to quickly perform pedal operation or lever operation, it is preferable that they are lighter in weight. However, the lighter the weight, the easier it is to lead to a large operation error unless the operation is performed more carefully. It would be ideal if careful operation could always be performed, but it is known that a person's concentration decreases due to fatigue from driving, and it is not always possible to exert maximum concentration.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Patent Document 5

Patent Document 6

Summary of the Invention

Problems to be Solved by the Invention

[0007] Therefore, the problem to be solved by the present invention is to provide a weight change system that can change the pedal operation and lever operation of a forklift or the weight of either of them in response to driving fatigue that causes a decrease in concentration.

Means for Solving the Problems

[0008] To solve the above problems, the weight change system according to the present invention used in a forklift includes a weight change unit that changes the weight of the pedal and lever of the forklift or either of them, a driving time memory unit that stores the continuous driving time, and a change command unit that, when a predetermined continuous driving time is reached, controls the weight change unit to change the weight of the pedal and lever or either of them to a second weight that is heavier than the first weight which is the normal weight.

[0009] Preferably, the weight change system further includes a driver identification unit that identifies the driver, and the driving time memory unit resets the continuous driving time when the driver is replaced by another driver.

[0010] Preferably, the weight change system further includes an interruption time memory unit that stores the driving interruption time, and the change command unit lightens the weight of the pedal and lever that have been made heavy or either of them when a predetermined driving interruption time has elapsed.

[0011] Preferably, the weight change system further includes a total operation time memory unit that stores the total operation time of a day, and the change command unit changes the weight of the pedal and lever or either of them to a third weight that is heavier than the second weight when a predetermined continuous driving time is reached and a predetermined total operation time is reached.

[0012] The above weight change system preferably further includes a change notice unit that notifies the driver that the weight of the pedal and the lever or either of them is changed.

[0013] The above weight change system preferably further includes a response receiving unit that receives the driver's response to the notice by the change notice unit, and after the response receiving unit receives the driver's response, the change command unit changes the weight of the pedal and the lever or either of them.

[0014] To solve the above problems, the forklift according to the present invention includes any one of the above weight change systems.

[0015] To solve the above problems, the weight change program according to the present invention is a program used in a weight change system including a weight change unit that changes the weight of the pedal and the lever of the forklift or either of them, and a computer, wherein the computer is caused to store the continuous operation time, and when a predetermined continuous operation time is reached, the weight change unit is controlled to change the weight of the pedal and the lever or either of them to a second weight heavier than the first weight which is the normal weight.

Effect of the Invention

[0016] The weight change system according to the present invention can change the pedal operation and lever operation of the forklift or the weight of either of them according to the driving fatigue that causes the concentration to decrease.

Brief Description of the Drawings

[0017]

Figure 1

Figure 2

Figure 3

Embodiments for Carrying Out the Invention

[0018] Hereinafter, an embodiment of the weight change system according to the present invention will be described with reference to the accompanying drawings. The weight change system S according to this embodiment is configured to change the weights of both the pedal and the lever, but this is merely an example, and the weight change system according to the present invention may be configured to change the weight of either the pedal or the lever.

[0019] <Configuration of Forklift> FIG. 1 is a front view of a forklift 1 equipped with a weight change system S. First, the configuration of the forklift 1 will be described. The forklift 1 is a battery-powered counterbalanced forklift. As shown in FIG. 1, the forklift 1 includes a plurality of wheels 10, a vehicle body 11, a driver's seat 12, a head guard 13, a pedal 14 (see FIG. 2), a lever 15, left and right masts 16, left and right forks 17, a camera 18, a speaker 19 (see FIG. 2), a microphone 20 (see FIG. 2), a weight change unit 21 (see FIG. 2), and a control unit 30 (see FIG. 2).

[0020] The plurality of wheels 10 are provided on the four sides of the vehicle body 11. The driver's seat 12 is provided on the vehicle body 11, and the head guard 13 is provided above the driver's seat 12.

[0021] The pedal 14 has an accelerator pedal, a brake pedal, and an inching pedal, and is provided below the driver's seat 12. The "pedal" in the present invention may have at least one pedal such as an accelerator pedal, a brake pedal, and an inching pedal, and does not necessarily have all of these pedals.

[0022] The lever 15 has a lift lever and a tilt lever, and is provided at the front part of the driver's seat 12. The lever 15 may have a slide lever for sliding the fork 17 left and right. The "lever" in the present invention may have at least one lever such as a lift lever and a tilt lever, and does not necessarily have all of these levers.

[0023] The left and right forks 17 are configured to be able to move up and down via the left and right masts 16. The driver H operates the lift lever to raise and lower the fork 17 to perform a loading and unloading operation.

[0024] The camera 18 is fixed to the head guard 13 and is configured to photograph the face of the driver H getting into the forklift 1 and generate a face image. The face image generated by the camera 18 is transmitted to the control unit 30.

[0025] The speaker 19 emits a warning voice for notifying the driver H of a weight change to be described later. The warning voice may be, for example, "Will you increase the weights of the pedal and the lever?" when the weights of the pedal 14 and the lever 15 are increased, or "Will you decrease the weights of the pedal and the lever?" when the weights of the pedal and the lever are decreased.

[0026] The microphone 20 collects the voice of the driver H's speech, converts the collected voice into a voice signal, and transmits it to the control unit 30.

[0027] The weight change unit 21 changes the weights of the lever 15 and the pedal 14 during operation based on a command from a change command unit 309 (see FIG. 2) to be described later. The weight change unit 21 has a pedal weight change unit for changing the weight of the pedal 14 and a lever weight change unit for operating the weight of the lever 15. Note that when the weight change unit 21 is configured to change the weight of either one of the pedal 14 and the lever 15, it will have either one of the pedal weight change unit and the lever weight change unit.

[0028] The pedal weight changing unit changes the weight of the pedal 14 when the driver H steps on it based on the command of the change command unit 309. The pedal weight changing unit is constituted by, for example, a device that can adjust the weight by hydraulic pressure or a device that can adjust the weight by a spring.

[0029] Also, for example, the pedal weight changing unit may be an assist device that assists the stepping force of the pedal 14. In this case, the pedal weight changing unit may adjust the assist force based on the command of the change command unit 309 and substantially change the weight of the pedal 14 when the driver H steps on it.

[0030] Alternatively, the pedal weight changing unit may be configured to change the magnitude of the driving force or braking force of each device that responds to the stepping amount of the pedal 14 based on the command of the change command unit 309, for example. Thereby, the pedal weight changing unit substantially changes the weight of the pedal 14.

[0031] The lever weight changing unit is constituted by, for example, a device that can adjust the weight of the lever 15 by hydraulic pressure or a device that can adjust the weight of the lever 15 by a spring.

[0032] Also, for example, the lever weight changing unit may be an assist device that assists the operation on the weight of the lever 15. In this case, the lever weight changing unit may adjust the assist force based on the command of the change command unit 309 and substantially change the weight of the lever 15 when the driver H operates it.

[0033] Alternatively, the lever weight changing unit may be configured to change the magnitude of the driving force of each device that responds to the operation amount of the lever 15 based on the command of the change command unit 309, for example. Thereby, the lever weight changing unit substantially changes the weight of the lever 15.

[0034] The control unit 30 is composed of a computer arranged inside the vehicle body 11, and has an arithmetic unit, a storage device, and a memory. The storage device stores a weight change program to be executed as a driver identification unit 302, a driving time storage unit 303, an interruption time storage unit 304, an accumulated time storage unit 305, a weight determination unit 306, a change notice unit 307, a response reception unit 308, and a change command unit 309, which will be described later for the computer.

[0035] <Functional Configuration of Weight Change System> Next, the functional configuration of the weight change system S will be described. As shown in FIG. 2, the control unit 30 includes a storage unit 301, a driver identification unit 302, a driving time storage unit 303, an interruption time storage unit 304, an accumulated time storage unit 305, a weight determination unit 306, a change notice unit 307, a response reception unit 308, and a change command unit 309.

[0036] The storage unit 301 stores face images of a plurality of drivers H.

[0037] The driver identification unit 302 refers to the face image generated by the camera 18 and the face images stored in the storage unit 301, and identifies the driver H who is about to board the vehicle from the plurality of drivers H stored in the storage unit 301.

[0038] The driving time storage unit 303 stores the continuous driving time during which the identified driver H drives continuously. Note that this continuous driving time may include, for example, a driving stop time of less than 5 minutes. Thereby, for example, a time different from an actual break such as a toilet break can be included in the continuous driving time.

[0039] Also, when the driver H is replaced by another driver, the driving time storage unit 303 resets the continuous driving time. The forklift 1 may have the driver H replaced for rest. Therefore, even in this case, if the continuous driving time is continuously stored, it is not preferable as it is different from the actual continuous driving time. Therefore, the driving time storage unit 303 prevents this by the above configuration.

[0040] The interruption time memory unit 304 stores the driving interruption time of 5 minutes or more. This interruption time is set to include, for example, meal breaks, breaks until starting overtime after regular working hours, breaks between operations, etc.

[0041] The cumulative time memory unit 305 stores the cumulative driving time from the start of the day's work. For example, when driver H starts work in the morning, takes a lunch break, and then starts afternoon work, the cumulative time memory unit 305 stores the morning working time excluding the lunch break and the afternoon working time as the cumulative driving time.

[0042] Note that the cumulative time memory unit 305 stores the cumulative driving time for each driver H. Thus, even when driver H is replaced, the actual cumulative driving time can be stored.

[0043] When the continuous driving time of driver H reaches a predetermined continuous driving time, the weight determination unit 306 determines to set the weights of the pedal 14 and the lever 15 to a second weight that is heavier than the first weight, which is the normal weight. The predetermined continuous driving time may be, for example, 1 hour. However, this predetermined continuous driving time is merely an example, and the predetermined continuous driving time in the present invention is not limited thereto. For example, the predetermined continuous driving time may be set differently for each driver H. In this case, the younger the age, the longer the predetermined continuous driving time may be set.

[0044] Further, when the cumulative driving time of the driver H reaches a predetermined cumulative driving time and upon reaching the predetermined cumulative driving time, the weight determination unit 306 determines to make the weights of the pedal 14 and the lever 15 heavier than the second weight to a third weight. The predetermined cumulative driving time may be, for example, 4 hours. However, this predetermined cumulative driving time is merely an example, and the predetermined cumulative driving time in the present invention is not limited thereto. For example, the predetermined cumulative driving time may be set differently for each driver H. In this case, the younger the age, the longer the predetermined cumulative driving time may be set. When the cumulative driving time of the driver H reaches the predetermined cumulative driving time and upon reaching the predetermined cumulative driving time, it is considered that the fatigue of the driver H has accumulated considerably. At this time, the weight determination unit 306 determines to make the weights of the pedal 14 and the lever 15 heavier than the second weight to an even heavier third weight.

[0045] Furthermore, when the driving is interrupted and the driving interruption time of the driver H elapses a predetermined driving interruption time, the weight determination unit 306 determines to make the weights of the heavier pedal 14 and lever 15 or either of them lighter. The predetermined driving interruption time may be set to 30 minutes. However, this predetermined driving interruption time is merely an example, and the predetermined driving interruption time in the present invention is not limited thereto.

[0046] In addition, in the present embodiment, when the weight determination unit 306 elapses a predetermined driving interruption time, it determines to make the weights of the pedal 14 and the lever 15 the first weight. This is also merely an example, and when the weight determination unit 306 elapses a predetermined driving interruption time and the immediately previous weight is the third weight, it may determine to make the weights of the pedal 14 and the lever 15 the second weight.

[0047] Further, the weight determination unit 306 determines that a predetermined driving interruption time has elapsed and the weights of the pedal 14 and the lever 15 are to be made lighter. When the weights of the pedal 14 and the lever 15 are changed accordingly, thereafter, the weight determination unit 306 may determine to maintain the weights of the pedal 14 and the lever 15 for a predetermined time. Thereby, it is possible to prevent the weights of the pedal 14 and the lever 15 that have been lightly changed from being immediately changed to a heavy weight. This predetermined time during which the weights of the pedal 14 and the lever 15 are maintained may be between 30 minutes and 1 hour, but this is not particularly limited either.

[0048] If the weights of the pedal 14 and the lever 15 determined by the weight determination unit 306 are different from the weights of the pedal 14 and the lever 15 at that time, the change notification unit 307 determines that it is necessary to change the weights of the pedal 14 and the lever 15. Then, when the change notification unit 307 determines that it is necessary to change the weights of the pedal 14 and the lever 15, the change notification unit 307 notifies the driver H of the change in the weights of the pedal 14 and the lever 15 by voice through the speaker 19. However, it is not preferable that the weights of the pedal 14 and the lever 15 are frequently changed. Therefore, the change notification unit 307 is configured to leave an arbitrary interval until the next notification after giving the notification. This interval may be set, for example, between 5 minutes and 30 minutes.

[0049] The response reception unit 308 receives a predetermined response of the driver H notified by the change notification unit 307 via the microphone 20. For example, the predetermined response may be words such as "yes", "I understand", "acknowledged". When the response reception unit 308 receives a predetermined response from the driver H, the response reception unit 308 transmits a response signal to the change command unit 309.

[0050] When receiving the response signal, the change command unit 309 controls the weight change unit 21 to change the weights of the pedal 14 and the lever 15 to the weights determined by the weight determination unit 306. Thereby, even if the concentration of the driver H fluctuates due to driving fatigue, the weight change system S can change the weights of the pedal 14 and the lever 15 according to the continuous driving time and the total driving time.

[0051] As a result, when the concentration of the driver H is high, the weight change system S can make the operations of the pedal 14 and the lever 15 quick by reducing the weights of the pedal 14 and the lever 15. Further, when the driver H gets tired, the weight change system S can prevent major operation mistakes by increasing the weights of the pedal 14 and the lever 15.

[0052] <Flow of the weight change system> Next, while referring to the flowchart of FIG. 3, the operation of the weight change system S according to the present embodiment will be described again.

[0053] (1) First, the weight change system S identifies the driver H by referring to the face image of the driver H (see S (step) 1 in FIG. 3).

[0054] (2) Next, the weight change system S stores the continuous driving time, the driving interruption time, and the cumulative driving time (see S2 in FIG. 3).

[0055] (3) Next, when a predetermined continuous driving time has elapsed (Yes in S3 in FIG. 3) and a predetermined cumulative driving time has not elapsed (No in S4 in FIG. 3), the weight change system S determines to set the weights of the pedal 14 and the lever 15 to the second weight (see S5 in FIG. 3). Further, when a predetermined continuous driving time has elapsed (Yes in S3 in FIG. 3) and a predetermined cumulative driving time has elapsed (Yes in S4 in FIG. 3), the weight change system S determines to set the weights of the pedal 14 and the lever 15 to the third weight (see S6 in FIG. 3). Furthermore, when the driving is interrupted (No in S3 in FIG. 3) and a predetermined driving interruption time has elapsed (Yes in S7 in FIG. 3), the weight change system S determines to set the weights of the pedal 14 and the lever 15 to the first weight (see S8 in FIG. 3).

[0056] (4) Next, if the determined weights of the pedal 14 and the lever 15 are different from the weights of the pedal 14 and the lever 15 at that time, the weight change system S determines that a change is necessary and notifies the driver H of the change in the weights of the pedal 14 and the lever 15 (see S9 in FIG. 3).

[0057] (5) Next, when the weight change system S receives permission for the change from the driver H (Yes in S10 of FIG. 3), the change command unit 309 changes the weights of the pedal 14 and the lever 15 (see S11 of FIG. 3). Further, until the weight change system S receives permission for the change from the driver H (No in S10 of FIG. 3), the weight change of the pedal 14 and the lever 15 is suspended, and the driver H is notified of the weight change of the lever 15 again after a predetermined time. Thereby, the weight change system S can prevent frequently changing the weights of the pedal 14 and the lever 15 and suddenly changing the weights of the pedal 14 and the lever 15 during the cargo handling work of the driver H.

[0058] As described above, the weight change system S changes the weights of the pedal 14 and the lever 15 based on the driving time of the driver H that affects the level of the driver H's concentration. As a result, when the driver H has a high level of concentration, the operations of the pedal 14 and the lever 15 can be performed quickly, and when the driver H has a low level of concentration, major operation mistakes can be prevented.

[0059] As described above, one embodiment of the weight change system S according to the present invention has been described. However, the present invention is not limited to this embodiment. The weight change system S according to the present invention may be implemented, for example, according to each of the following modification examples or a combination of the modification examples.

[0060] <Modification Example> · The forklift 1 may be a reach forklift. In this case, the pedal 14 may include a presence pedal. Also, the forklift 1 may be an engine-powered forklift. In this case, the pedal 14 may include a clutch pedal. Further, when the forklift 1 is a reach forklift, the lever 15 may include an accelerator lever. Also, as described above, the "pedal" in the present invention includes at least one of the above pedals, the "lever" includes at least one of the above levers, and the weight change system according to the present invention changes the weight of at least one of the above lever and pedal.

[0061] · Any configuration of the control unit 30 may be configured by, for example, a server computer provided on the cloud. In this case, the weight change system S communicates with this server computer to change the weight of the pedal 14 and the lever 15 or either of them.

[0062] · The method for identifying the driver H by the driver identification unit 302 is not particularly limited. For example, the driver identification unit 302 may identify each driver H by reading a card or the like possessed by each driver H.

[0063] · The forklift 1 is provided with a monitor instead of the speaker 19, and the change notification unit 307 may notify the change of the weight of the lever 15 and the pedal 14 or either of them by this monitor.

[0064] · The forklift 1 is provided with a button instead of the microphone 20, and the response reception unit 308 may receive a response from the driver H via the button.

Explanation of Signs

[0065] S Weight change system H Driver 1 Forklift 10 Wheels 11 Vehicle body 12 Driver's seat 13 Head guard 14 Pedal 15 Lever 16 Mast 17 Fork 18 Camera 19 Speaker 20 Microphone 21 Weight change unit 30 Control unit 301 Memory unit 302 Driver identification unit 303 Driving time memory unit 304 Interruption time memory unit 305 Total operation time memory unit 306 Weight determination unit 307 Change notice unit 308 Response receiving unit 309 Change command unit

Claims

1. A weight change system used in a forklift, comprising: a weight change unit that changes the weight of the pedal and lever of the forklift or either of them; an operation time storage unit that stores the continuous operation time; a change command unit that, when a predetermined continuous operation time is reached, controls the weight change unit to change the weight of the pedal and the lever or either of them to a second weight that is heavier than a first weight which is the normal weight.

2. Further comprising a driver identification unit that identifies a driver, wherein the operation time storage unit resets the continuous operation time when the driver is replaced by another driver. The weight change system according to Claim 1.

3. Further comprising an interruption time storage unit that stores the operation interruption time, wherein the change command unit lightens the weight of the pedal and the lever or either of them that has been made heavy when a predetermined operation interruption time has elapsed. The weight change system according to Claim 1.

4. Further comprising a total operation time storage unit that stores the total operation time of one day, wherein the change command unit changes the weight of the pedal and the lever or either of them to a third weight that is heavier than the second weight when a predetermined continuous operation time is reached and a predetermined total operation time is reached. The weight change system according to Claim 1.

5. Further comprising a change notice unit that notifies the driver that the weight of the pedal and the lever or either of them is to be changed. The weight change system according to Claim 1.

6. Further comprising a response receiving unit that receives the driver's response to the notice by the change notice unit, wherein the change command unit changes the weight of the pedal and the lever or either of them after the response receiving unit receives the response from the driver. The weight change system according to Claim 5.

7. The forklift comprising the weight change system according to any one of Claims 1 to 6.

8. A program used in a weight change system comprising a weight change unit that changes the weight of a pedal and lever of a forklift or either of them and a computer, wherein the computer is caused to: store the continuous operation time; when a predetermined continuous operation time is reached, control the weight change unit to change the weight of the pedal and the lever or either of them to a second weight that is heavier than a first weight which is the normal weight. A weight change program.

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