JP6749875B2 - Seat belt wearing detection device - Google Patents

Description

The present invention relates to a technique for detecting whether an operator of a construction machine is wearing a seat belt correctly.

From the viewpoint of safety, an operator who operates a construction machine such as a hydraulic excavator or a wheel roller needs to wear a seat belt when sitting in a driver's seat.

As a technique for detecting the seatbelt wearing state, there is disclosed a technique of not only detecting the seatbelt connecting state but also detecting the presence of a person who needs to be worn and determining the wearing state according to the conditions of both. Patent Document 1). According to Patent Document 1, the presence/absence of a human body is detected by a human body detection pressure sensor, the buckle coupling state is detected by a seat buckle sensor, and the presence or absence of a seatbelt is determined based on the detection signals of both. When not installed, the indicator light above the seat is turned on.

JP-A-2-102858

When the operator wears the seat belt, the belt is passed through the abdomen side of the operator, and then the connecting portion of the belt is inserted into the buckle. Then, by tightening the seat belt so that the operator and the driver's seat are integrated, the seat belt is properly worn. On the other hand, even if the operator is seated and the belt connecting portion is inserted into the buckle through the belt on the back side, in the above Patent Document 1, it is erroneously recognized that the operator correctly wears the seat belt.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a technique that enables an operator to detect whether or not a seatbelt is correctly worn.

In order to solve the above problems, a typical seatbelt wearing detection device of the present invention is a seatbelt wearing detection device that detects whether an operator is wearing a seatbelt, and a belt connecting portion is inserted into a buckle. A belt insertion detector that detects whether or not the belt is wound, a belt winding length detector that detects the winding length that is the length of the belt wound by the winding device, and a notification device that issues a warning. And the signal input from the belt insertion detector determines that the belt connecting portion is inserted, and is calculated based on the signal input from the belt winding length detector. If the withdrawal length of the belt withdrawn from the winding device is shorter than the first specified length, the notification device outputs a warning signal so that the notification device issues a warning, and the seating portion of the seat. A seating detector that detects whether the operator is seated, and the length of the belt pulled out from the winding device when the seat belt is mounted while the operator is seated, the reference mounting length. A storage unit for storing as, the control device further determines, based on a signal input from the seating detector, that the operator is not seated, and the withdrawal length is the reference. When it is longer than the length obtained by adding the third specified length to the mounting length, the notification device outputs a warning signal so as to issue a warning .

According to the present invention, it is possible to detect whether the operator is wearing the seat belt correctly.
Problems, configurations, and effects other than those described above will be clarified by the following description of the embodiments.

It is a side view showing a hydraulic excavator. It is a perspective view showing an example of a driver's cab of an embodiment. It is a block diagram showing composition of a seat belt wearing detection device of an embodiment. It is a flow chart which shows the 1st example of operation of the control device of an embodiment. It is a flow chart which shows the 2nd example of operation of the control device of an embodiment.

Hereinafter, the seatbelt wearing detection device according to the embodiment will be described with reference to the drawings. The X-axis, Y-axis, and Z-axis coordinate axes shown in FIGS. 1 and 2 indicate common directions. Further, the plus direction of the X axis is the left direction, the minus direction is the right direction, the plus direction of the Y axis is the up direction, and the minus direction is the down direction. The positive direction of the Z axis is the front and the negative direction is the rear. Each direction is defined based on the work posture shown in FIG.

FIG. 1 is a diagram showing a hydraulic excavator as an example of a construction machine. The hydraulic excavator 1 has a traveling body 7 and a revolving body 2 which is disposed on the traveling body 7 and constitutes a main body. Further, the hydraulic excavator 1 is equipped with a working device 3 which is attached to the revolving structure 2 and includes a boom 3a, an arm 3b, and a bucket 3c that are vertically rotatable.

A driver's cab 4 is provided at a front position of the revolving structure 2, and a counterweight 5 is provided at a rear position thereof. An engine compartment 6 and the like are arranged between the driver's cab 4 and the counterweight 5.

FIG. 2 is a perspective view showing the inside of the cab 4. A right operation lever 40R and a left operation lever 40L are provided on the left and right sides of the driver's seat 10, respectively. The right operation lever 40R is a lever for performing operations of raising and lowering the boom 3a and raising and lowering the bucket 3c. The left operation lever 40L is a lever for performing the operations of the dump and cloud of the arm 3b and the left and right rotation of the swing body 2. The correspondence between the operation direction of each lever and each operation is not limited to the above pattern.

A right side traveling lever 30R and a left side traveling lever 30L are arranged in front of the driver's seat 10. The right crawler of the traveling body 7 moves forward or backward by operating the right traveling lever 30R forward or backward. Further, the left crawler of the traveling body 7 moves forward or backward by operating the left traveling lever 30L back and forth. When the operator simultaneously operates the left and right levers 30R and 30L, both crawlers operate at the same time, and the hydraulic excavator 1 moves straight or reverse.

The right pedal 20R is arranged at the base of the floor surface of the right traveling lever 30R, and interlocks with the movement of the right traveling lever 30R. The left pedal 20L is arranged at the base of the floor surface of the left traveling lever 30L, and interlocks with the movement of the left traveling lever 30L. That is, the right crawler and the left crawler can also perform forward/backward movements by pedaling the right pedal 20R and the left pedal 20L. Further, when the operator simultaneously depresses the pedals 20R and 20L, the hydraulic excavator 1 goes straight, and by making a step difference, the steering of the hydraulic excavator 1 can be controlled.

In this way, the operator operates the lever or the pedal by using the limbs, so that the hydraulic excavator 1 operates according to the operation of the operator.

The driver's seat 10 is roughly divided into a backrest portion 10A and a seating portion 10B, and a pressure sensor 106 (seating detector) for detecting the operator's seating is installed in the central portion of the seating portion 10B. On the right side of the driver's seat 10 is a buckle 60 that is connected to the connecting portion 51 of the belt 50, and on the left side is a retractor 70 that is a winding device that stores a part or the whole of the belt 50. ..

The gate lock lever 45 is a lever that controls the hydraulic excavator 1 so that the hydraulic excavator 1 does not malfunction even if the operating levers 40R and 40L are accidentally operated when getting on and off the vehicle. The operator operates the gate lock lever 45 to shut off the pilot pressure for operating the hydraulic excavator 1. This prevents the hydraulic excavator 1 from operating in conjunction with the operation levers 40R and 40L.

FIG. 3 is a block diagram of the seatbelt wearing detection device 100 of the present embodiment. The control device 101 is a control unit having a function of comprehensively controlling the operation of each device and sensor illustrated in FIG. 3, and includes an input unit 161, a calculation unit 162, a storage unit 163, and an output unit 164.

The input unit 161 inputs a switch signal corresponding to the operation of the gate lock lever 45, and also inputs an ON/OFF signal indicating the driving/non-driving state of the engine 152 from the ALT regulator signal detecting unit 103. Further, the input unit 161 inputs a detection signal indicating whether or not the connecting portion 51 of the belt 50 is inserted into the buckle 60 from the micro switch 104 incorporated in the buckle 60. That is, the micro switch 104 functions as a belt insertion detector that detects whether or not the belt 50 is in the tightened state.

The input unit 161 inputs the winding length of the belt 50 by the retractor 70 from the displacement sensor 105 (belt winding length detector) built in the retractor 70. The displacement sensor 105 detects the winding length, which is the length at which the retractor 70 is currently winding the belt 50, and outputs this winding length to the control device 101. The control device 101 determines the length of the belt 50 pulled out from the retractor 70 based on the winding length input via the input unit 161 and the total length (specified value) of the belt 50 stored in the storage unit 163. Can be derived. That is, the control device 101 derives the pull-out length of the belt from the retractor 70 by subtracting the winding length from the total length of the belt 50.

The input unit 161 inputs a detection signal indicating whether or not pressure is applied from the pressure sensor 106 built in the seating portion 10B of the driver's seat 10. That is, the pressure sensor 106 functions as a unit that detects whether the operator is seated in the driver's seat 10.

The arithmetic unit 162 performs arithmetic processing using control data and set value data in accordance with an operation control program stored in the storage unit 163. The operation of the flowchart described below is realized by the arithmetic unit 162 performing arithmetic processing. The output unit 164 outputs a warning signal to a notification device such as the monitor 111 or the buzzer 112 according to the result processed by the calculation unit 162. The warning signal may be, for example, a warning message (text data) for display or voice data for warning. In addition, the output unit 164 outputs a control signal to an ECU 151 (ECU: Engine control unit) that is an engine controller according to the result of the arithmetic processing performed by the arithmetic unit 162. The ECU 151 includes a microcomputer that electronically controls the engine 152. When a control signal is input from the output unit 164, the ECU 151 controls the rotation speed and torque of the engine 152 so that they are within specified values, and limits the engine output. Set up. The storage unit 163 includes a main storage device that is a volatile storage unit and an auxiliary storage device that is a non-volatile storage unit, and is a unit that stores data and programs.

The monitor 111 is a touch-operable panel that displays the operating status of the hydraulic excavator 1 and setting parameters for the operator. The monitor 111 may be a lamp that gives a warning by lighting or blinking. The buzzer 112 is a unit including a speaker that emits a voice announcement and a warning sound. Either or both of the monitor 111 and the buzzer 112 display a message warning the operator that the seatbelt is not properly seated or sound an alarm sound in response to the warning signal output from the control device 101. To do

Next, the control operation of the control device 101 will be described with reference to the flowchart. In detecting whether or not the seat belt is properly worn, first, a first operation example when the pressure sensor 106 of the driver's seat 10 is not used will be described, and then a second operation example when the pressure sensor 106 is used will be described. To do.

FIG. 4 is a flowchart showing the first operation example. The control device 101 determines whether the engine 152 is driven based on the signal from the ALT regulator signal detection unit 103 (S001). When the engine 152 is not driven (S001: No), the control device 101 does not warn (S003), and the process returns to step S001. When the engine 152 is driven (S001: Yes), the control device 101 determines whether the gate lock lever 45 is released (S002). When the gate lock lever 45 is not released, that is, when the mechanical operation of the hydraulic excavator 1 via the operation levers 40R, 40L and the like is suppressed (S002: No), the control device 101 does not warn. (S003), the process returns to step S001. In the present embodiment, when the hydraulic excavator 1 is in a stationary state or in a state in which the operation is suppressed as described above, it is treated that the seat belt need not be worn, and no warning is issued.

When the gate lock lever 45 is released and the mechanical operation of the hydraulic excavator 1 is possible (S002: Yes), the control device 101 controls the seat belt based on the signal input from the micro switch 104. It is determined whether or not is locked (S004). When the seat belt is removed (S004: No), the control device 101 outputs a warning signal (S006). As a result, the monitor 111 displays a warning message and the buzzer 112 sounds. Then, the control device 101 outputs a control signal to the ECU 151 in order to control the rotation speed and torque of the engine 152 so as not to exceed the specified values (S007).

When the seat belt is in the locked state (S004: Yes), the control device 101 pulls out from the retractor 70 based on the value (winding length) of the signal input from the displacement sensor 105 incorporated in the retractor 70. The length (pull-out length) of the belt 50 is calculated. The length of the belt 50 pulled out from the retractor 70 (in other words, the belt length that is not wound by the retractor 70) is referred to as the belt pull-out length.

The control device 101 determines whether the current belt withdrawal length is longer than La, which is the first specified length (S005). Here, the value obtained by adding the specified length (here, 10 cm) to the belt withdrawal length when the connecting portion 51 of the belt 50 is inserted into the buckle 60 in the vacant state where no one is seated is defined as the specified value La. .. The storage unit 163 stores the belt withdrawal length and the specified value La in the empty seat state in advance.

When the current belt withdrawal length is equal to or less than the specified value La (S005: No), it is considered that the belt 50 is worn through the operator's back side, and in the present embodiment, the belt is not properly worn. Treat as. In this case, warning and engine restriction operations are performed (S006, S007). Then, it returns to step S001.

When the current belt pull-out length is longer than the specified value La (S005: Yes), the control device 101 determines whether the current belt pull-out length is longer than the specified value Lb (second specified length) (S008). ). Here, the value obtained by adding the specified length (here, 70 cm) to the belt withdrawal length when the connecting portion 51 of the belt 50 is inserted and attached to the buckle 60 in the empty seat state is defined as the specified value Lb. The specified length of 70 cm is a length at which it can be considered that the operator is seated in the driver's seat 10 and the seat belt is correctly tightened through the abdomen side of the operator. Further, when the operator visually confirms, for example, the near side of the hydraulic excavator 1 or the rear of the vehicle, the operator needs to lean a little, but the prescribed length of 70 cm allows this leaning posture with the seat belt worn. It is also the length provided to do this.

If the current belt withdrawal length is longer than the specified value Lb (S008: Yes), the belt is treated as a launching posture that exceeds the allowable range, and warning and engine limiting operations are performed (S006, S007). On the other hand, when the current belt withdrawal length is equal to or less than the specified value Lb (S008: No), it is considered that the seatbelt is correctly worn or the vehicle is in a to-be-leaked posture, and the control device 101 does not give a warning. (S009), the process is returned to step S001.

FIG. 5 is a flowchart showing a second operation example using the pressure sensor 106 of the driver's seat 10. The operation of steps S001 to S007 shown in FIG. 5 is similar to that of steps S001 to S007 shown in FIG.

In step S005, when the current belt withdrawal length is longer than the specified value La (S005: Yes in FIG. 5), the control device 101 causes the operator to sit on the driver's seat 10 based on the signal input from the pressure sensor 106. It is determined whether or not (S101). If the user is seated (S101: Yes), the control device 101 returns the process to step S001 in FIG. 5 without giving a warning (S102).

When the user is not seated (S101: No), the control device 101 then determines, based on the value from the displacement sensor 105, that the current belt withdrawal length is Lc( It is determined whether the length is longer by the (third prescribed length) (S103). Here, the seat-locked length is the belt withdrawal length when the operator is seated and the seat belt is correctly worn by passing the belt on the abdomen side. The specified value Lc is, for example, 30 cm, which is a belt withdrawing length for allowing the operator to take a slightly leaning posture while wearing the seat belt. In step S103, it is determined whether or not the current belt withdrawal length is longer than the length when the seat is locked and the specified value Lc is added. The length when the seat is locked is registered by the operator operating the monitor 111 in advance and stored in the storage unit 163. Alternatively, it may be overwritten and updated in the storage unit 163 every time the operator sits down and correctly wears the belt.

When step S103 is negative (S103: No), the process returns to step S001 of FIG. 5 without giving a warning in this embodiment (S106). On the other hand, if step S103 is affirmative (S103: Yes), in the present embodiment, the operator is considered to be in a posture in which he/she has embarked beyond the allowable range, and a warning or engine restriction operation is performed (S104, S105). Then, the process returns to step S001 in FIG.

In the present embodiment, a hydraulic excavator has been described as an example of the construction machine, but the present invention is not limited to this, and the aspect of the present embodiment can be applied to any vehicle in which a passenger wears a seat belt.

The numerical values shown in the above embodiment are merely examples. Further, the warning sound emitted by the buzzer 112 and the display content displayed by the monitor 111 may be different depending on the presence/absence of the operator's seating or the state of the leaning posture. Further, the first operation example shown in FIG. 4 and the second operation example shown in FIG. 5 may be combined with each other.

As described above in detail, in the aspect of the present embodiment, the withdrawal length of the belt from the retractor 70 is added to the determination element, and it is possible to detect whether the operator is properly wearing the seat belt based on the withdrawal length. it can. In addition, by allowing a slightly leaning posture for backward confirmation and the like, it is possible to prevent the warning from being frequently activated. Further, even when the engine 152 is stopped or the operation of the hydraulic excavator 1 is suppressed, the warning regarding the seat belt is not issued in the present embodiment. In the present embodiment, when the seat belt is not properly worn, in addition to the warning, the engine is controlled to have a low rotation speed and a low torque, so that safety is considered even if the vehicle operates. It can be the output of the engine.

1: Hydraulic excavator 4: Driver's cab 10: Driver's seat 45: Gate lock lever 50: Belt 51: Connection part 60: Buckle 70: Retractor 100: Seat belt wearing detection device 101: Control device 103: ALT regulator signal detection part 104 : Micro switch 105: Displacement sensor 106: Pressure sensor 111: Monitor 112: Buzzer 151: ECU
152: Engine

Claims (6)

A seat belt wearing detection device for detecting whether an operator wears a seat belt,
A belt insertion detector that detects whether or not the connecting portion of the belt is attached to the buckle,
A belt winding length detector that detects a winding length, which is the length of the belt wound by the winding device,
A notification device that issues a warning,
The signal input from the belt insertion detector determines that the connecting portion of the belt is inserted, and is calculated based on the signal input from the belt winding length detector. A controller that outputs a warning signal so that the notification device issues a warning when the withdrawal length of the belt withdrawn from the winding device is shorter than the first specified length;
A seating detector that detects whether the operator is seated on the seating portion of the seat,
A storage unit that stores the length of the belt pulled out from the winding device when the operator wears the seat belt in a seated state, as a reference wearing length,
The control device further determines, based on a signal input from the seating detector, that the operator is not seated, and the pull-out length is the reference mounting length plus a third specified length. The seatbelt wearing detection device is characterized in that it outputs a warning signal so that the notification device gives a warning when the length is longer than the predetermined length . The seat belt wearing detection device according to claim 1,
The control device outputs a warning signal so that the notification device issues a warning when the withdrawal length of the belt is longer than the second prescribed length which is longer than the first prescribed length. Seatbelt wearing detection device characterized by: The seatbelt wearing detection device according to claim 1 or 2 ,
The seat belt wearing detection device, wherein the control device further outputs a control signal for limiting the output of the engine to the engine controller when outputting the warning signal. The seat belt wearing detection device according to any one of claims 1 to 3 ,
The seatbelt wearing detection device, wherein the control device does not output a warning signal when the operation in the driver's cab is suppressed. The seat belt wearing detection device according to any one of claims 1 to 4 ,
The seatbelt wearing detection device, wherein the control device does not output a warning signal when the engine is not driven. The seat belt wearing detection device according to any one of claims 1 to 5 ,
The first specified length is defined based on the length of the belt pulled out from the winding device when the connecting portion of the belt is inserted into the buckle while the operator is not seated on the seat. Seatbelt wearing detection device characterized in that the seatbelt wearing detection device has a predetermined length.

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