The present disclosure relates to a crawler monitoring system, a crawler apparatus, a crawler vehicle, and a crawler monitoring method.
As a related art, for example, JP2011011622A (PTL 1) describes a monitoring device capable of determining, based on detected vibration data detected by a sensor and predicted vibration data predicted based on product information stored in an IC tag, whether a rubber crawler is abnormal.
PTL 1: JP2011011622A
As a driving system of an elastic crawler, there is a system called a guide driving system. In the driving system, guide projections (drive projections) provided on an inner circumferential surface of the elastic crawler are pressed by drive pins provided on a drive sprocket, the drive sprocket rotates on the inner circumferential surface of the elastic crawler, and thus the elastic crawler is driven.
In the guide driving system, for example, when a large load is applied to the elastic crawler, the drive pins of the drive sprocket may ride over the guide projections of the elastic crawler. A phenomenon that the drive pins of the drive sprocket ride over the guide projections of the elastic crawler is also called “jumping”. The “jumping” may cause damage or dropout of the guide projections.
However, since the related art relates to the monitoring device for determining an abnormality of the elastic crawler, jumping cannot be prevented in advance.
The present disclosure is to provide a crawler monitoring system, a crawler apparatus, a crawler vehicle, and a crawler monitoring method capable of preventing jumping in advance.
A first aspect according to the present disclosure provides a crawler monitoring system configured to monitor a crawler apparatus including: an elastic crawler provided with a drive projection on an inner circumferential surface; and a drive sprocket including a drive pin capable of pressing the drive projection of the elastic crawler, and being rotatable along the inner circumferential surface of the elastic crawler, the crawler monitoring system including: a sensor configured to acquire information on a distance between the inner circumferential surface of the elastic crawler and the drive sprocket;
and a monitoring member configured to acquire the information from the sensor and monitor whether a measured value measured based on the information is a preset predetermined value or more.
A second aspect according to the present disclosure provides a crawler apparatus including: an elastic crawler provided with a drive projection on an inner circumferential surface; a drive sprocket including a drive pin capable of pressing the drive projection of the elastic crawler, and being rotatable along the inner circumferential surface of the elastic crawler; and the crawler monitoring system.
A third aspect according to the present disclosure provides a crawler vehicle in which a crawler apparatus is disposed on a vehicle front side and a vehicle rear side, the crawler apparatus including: an elastic crawler provided with a drive projection on an inner circumferential surface; and a drive sprocket including a drive pin capable of pressing the drive projection of the elastic crawler, and being rotatable along the inner circumferential surface of the elastic crawler, the crawler vehicle further including the crawler monitoring system, the sensor being provided in at least one crawler apparatus of the crawler apparatus on the vehicle front side and the crawler apparatus on the vehicle rear side.
A fourth aspect according to the present disclosure provides a crawler monitoring method for monitoring a crawler apparatus in which a drive projection provided on an inner circumferential surface of an elastic crawler is pressed by a drive pin provided on a drive sprocket and the drive sprocket rotates along the inner circumferential surface of the elastic crawler, the crawler monitoring method including: acquiring information on a distance between the inner circumferential surface of the elastic crawler and the drive sprocket; and monitoring whether a measured value measured based on the information is a preset predetermined value or more.
According to the present disclosure, it is possible to provide a crawler monitoring system, a crawler apparatus, a crawler vehicle, and a crawler monitoring method capable of preventing jumping in advance.
In the accompanying drawings:
A crawler monitoring system, a crawler apparatus, a crawler vehicle, and a crawler monitoring method according to an embodiment of the present disclosure will be described below with reference to the drawings.
In
In the present embodiment, the elastic crawler 31 is a coreless elastic crawler. The elastic crawler 31 is made of an elastic material. In this example, the elastic material is rubber. The elastic crawler 31 includes a crawler body 31a, drive projections 31b, and lugs 31c.
The crawler body 31a is formed in a shape of an endless belt. In the present embodiment, the crawler body 31a includes steel cord layers 32 and reinforcement plies 33 having one layer or a plurality of layer (three layers in the drawing as an example) which are embedded inside the crawler body 31a. Each of the steel cord layers 32 is formed of a plurality of steel cords 32a extending in parallel in the crawler circumferential direction. Each of the reinforcement plies 33 is disposed on an outer circumferential side of the crawler compared with the steel cord layers 32. The reinforcement ply 33 includes, for example, a plurality of cords inclined in the crawler circumferential direction. However, the reinforcement ply 33 may not be provided.
In the present embodiment, the elastic crawler 31 includes the plurality of drive projections 31b. Each of the plurality of projections 31b protrudes from the inner circumferential surface of the crawler body 31a toward the crawler inner circumferential side. In the present embodiment, the inner circumferential surface of the crawler body 31a corresponds to the inner circumferential surface 31f1 of the elastic crawler 31. In addition, the plurality of drive projections 3 lb are arranged at regular intervals in the crawler circumferential direction. In the present embodiment, the drive projection 31b are respectively disposed at a center of the crawler body 31a in the crawler width direction.
In the present embodiment, the elastic crawler 31 includes the plurality of lugs 31c. Each of the plurality of lugs 31c protrudes from the outer circumferential surface of the crawler body 31a toward the crawler outer circumferential side. In the present embodiment, the outer circumferential surface of the crawler body 31a corresponds to the outer circumferential surface 31f2 of the elastic crawler 31. The shapes and arrangement of the lugs 31c are not limited to those illustrated in the drawings, and any shape and arrangement thereof may be adopted.
In the present embodiment, the drive projections 31b and the lugs 31c can be formed integrally with the crawler body 31a. Further, the drive projections 31b and the lugs 31c can adhere to the crawler body 31a with vulcanization.
Referring to
The drive wheel 34 can spontaneously rotate around a rotational axis O using an internal combustion engine such as an engine or a motor as a driving source 10 (see
Referring again to
Referring to
The crawler apparatus 3 operates as follows, for example. As indicated by an arrow RD in
However, as described above, when a driving system of the elastic crawler 31 is a so-called guide driving system in which the drive pins 34b of the drive wheel 34 presses the drive projections 31b of the elastic crawler 31 to drive the elastic crawler 31, the drive pins 34b of the drive wheel 34 ride over the drive projections 31b provided on the elastic crawler 31, and thus a phenomenon called “jumping” may occur.
Since the “jumping” occurs when the drive pins 34b of the drive wheel 34 ride over the drive projections 31b of the elastic crawler 31, the “jumping” can be prevented in advance by monitoring of riding of the drive pins 34b over the drive projections 31b.
When the elastic crawler 31 is wound around the drive wheel 34, the inner circumferential surface 31f1 of the elastic crawler 31 is in contact with the outer circumferential surface 34f1 of the drive wheel 34. However, when the drive pins 34b of the drive wheel 34 try to ride over the drive projections 31b of the elastic crawler 31, a gap is formed between the inner circumferential surface 31f1 of the elastic crawler 31 and the outer circumferential surface 34f1 of the drive wheel 34, as indicated by reference numeral D1 in
Therefore, according to the present disclosure, a sensor 4a acquires information S on the distance D1 between the inner circumferential surface 31f1 of the elastic crawler 31 and the outer circumferential surface 34f1 of the drive wheel 34, thereby monitoring the occurrence of the “jumping”. In the present embodiment, the distance D1 is a gap between the inner circumferential surface 31f1 of the elastic crawler 31 and the outer circumferential surface 34f1 of the drive wheel 34.
The distance D1 can be calculated, as a measured value D, based on the information S acquired by the sensor 4a. When it is determined that the distance D1 calculated based on the information S is a preset predetermined value Dv1 or more, it is considered that “jumping” may occur, and a countermeasure is taken to prevent the “jumping”. As such a measure, for example, an operator is notified by visual means or auditory means that the rotation of the drive wheel 34 may be reduced or stopped or the “jumping” may occur.
The crawler monitoring system 4 is a system that monitors the crawler apparatus 3. Herein, the crawler monitoring system 4 includes not only a system that monitors at least one of the four crawler apparatuses 3 as a whole, but also individual crawler monitoring devices provided respectively in the four crawler apparatuses 3. The crawler monitoring system 4 includes a sensor 4a and a monitoring member 4b. The sensor 4a is a sensor configured to acquire the information S on the distance D1 between the inner circumferential surface 31f1 of the elastic crawler 31 and the drive wheel 34. The monitoring member 4b acquires the information S from the sensor 4a, and monitors whether the measured value D measured based on the information S is a preset predetermined value Dv or more. When the measured value D is the distance D1, an example of the predetermined value Dv1 may include a value Dv1 (hereinafter, also referred to as a “predetermined value Dv1”) corresponding to the gap between the inner circumferential surface 31f1 of the elastic crawler 31 and the outer circumferential surface 34f1 of the drive wheel 34 immediately before the drive pin 34b rides over the drive projection 31b. More preferably, an example of the predetermined value Dv1 may include a value corresponding to the gap between the inner circumferential surface 31f1 of the elastic crawler 31 and the outer circumferential surface 34f1 of the drive wheel 34 such that the drive pin 34b is pushed back by an elastic force of the drive projection 31b without riding over the drive projection 31b when a drive member 4c such as an engine is stopped.
An example of the sensor 4a may include a sensor configured to acquire information S on a distance Do to the inner circumferential surface 31f1 of the elastic crawler 31. An example of such a sensor may include a displacement sensor (displacement meter). According to the displacement sensor, it is possible to acquire not only the information S on the distance Do between the sensor 4a and the inner circumferential surface 31f1 of the elastic crawler 31 but also the information S on a displacement ΔD of the inner circumferential surface 31f1 of the elastic crawler 31 with respect to the sensor 4a, as the information S on the distance D1.
In the present embodiment, as illustrated in
However, as in the displacement sensor, it is preferable that the information S on the displacement ΔD when the inner circumferential surface 31f1 of the elastic crawler 31 is displaced with respect to the sensor 4a. In this case, the monitoring member 4b acquires the information S from the sensor 4a, sets the displacement ΔD measured based on the information S as the measured value D, and monitors whether the displacement ΔD is a preset predetermined value Dv2 or more. The displacement ΔD is a positional displacement (displacement amount) of the inner circumferential surface 31f1 of the elastic crawler 31 when the inner circumferential surface 31f1 of the elastic crawler 31 is displaced with respect to the sensor 4a. Referring to
In the crawler monitoring system 4, when determining that the measured value D is the predetermined value Dv or more, the monitoring member 4b preferably reduces or stops the rotation of the drive wheel 34, or notifies that the measured value D is the predetermined value Dv or more. In this case, the jumping of the drive wheel 34 can be forcibly or indirectly prevented in advance.
In the crawler monitoring system 4, the monitoring member 4b controls the drive member 4c and a notification member 4d based on the information S acquired from the sensor 4a to prevent the jumping in advance.
Referring to
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The notification member 4d includes an alarm device that issues an alarm to an operator (driver) in a driving cab 2a of the vehicle body 2. Examples of the alarm device may include perception devices, for example, a visual device and an auditory device. When the notification member 4d is a visual device, the monitoring member 4b controls the visual device to issue an alarm to the operator. The visual device displays visual information, for example, colors, letters, and symbols. Examples of the visual device may include a display, a monitor, and an alarm lamp disposed in the driving cab 2a. When the notification member 4d is an auditory device, the monitoring member 4b controls the auditory device to issue an alarm to the operator. The auditory device produces sounds such as voice. Examples of the auditory device may include a buzzer and a speaker.
In the present embodiment, the sensor 4a is located to be overlapped on a width direction end 31e of the elastic crawler 31 in the crawler width direction as viewed in the crawler circumferential direction.
In the present embodiment, the sensor 4a is disposed on a sprocket frame 37. The sprocket frame 37 is used to fix the drive wheel 34 to the vehicle body 2. Referring to
Further, as illustrated in
In addition, as illustrated in
In the present embodiment, the sensor 4a is fixed to an inner side surface (side surface on the frame side) 37f1 of the sprocket frame 37. Thus, the sensor 4a can be prevented from being exposed to direct sunlight. Each of the heat insulating member 5 and the cushion member 6 preferably covers the entire sensor 4a excluding a detection member of the sensor 4a. In the present embodiment, the sensor 4a is fixed to the sprocket frame 37 through the heat insulating member 5 and the cushion member 6. In this case, the sensor 4a may be fixed to the sprocket frame 37 through at least one of the heat insulating member 5 and the cushion member 6. When the heat insulating member 5 and the cushion member 6 are laminated, the order of laminating the heat insulating member 5 and the cushion member 6 from the sprocket frame 37 is not particularly limited. Further, the heat insulating member 5 and the cushion member 6 can be configured by one member having both heat insulating performance and cushion performance (vibration-proof/vibration-damping performance). Examples of such a member may include a polyurethane foam member, a rubber member, and a silicon member.
The crawler monitoring method according to the present embodiment is performed in real time at a predetermined sampling frequency. The crawler monitoring method according to the present embodiment is initiated by starting the operation of the power source 10 such as an engine or a motor.
Referring to
In the present embodiment, the distance D1 is a gap between the inner circumferential surface 31f1 of the elastic crawler 31 and the outer circumferential surface 34f1 of the drive wheel 34. When D1≤0, the inner circumferential surface 31f1 of the elastic crawler 31 and the outer circumferential surface 34f1 of the drive wheel 34 are in contact with each other without a gap therebetween. On the other hand, when D1>0, the inner circumferential surface 31f1 of the elastic crawler 31 and the outer circumferential surface 34f1 of the drive wheel 34 are separated from each other with a gap formed therebetween.
In the present embodiment, the information S acquired by the sensor 4a is information on the positional displacement ΔD of the inner circumferential surface 31f1 of the elastic crawler 31 with respect to the sensor 4a. As described above, the displacement ΔD is a displacement of the inner circumferential surface 31f1 of the elastic crawler 31 with reference to the position (apex P) where the inner circumferential surface 31f1 of the elastic crawler 31 is in contact with the outer circumferential surface 34f1 of the drive wheel 34. A vector of the displacement is positive in a direction away from the sensor 4a. In the present embodiment, when ΔD≤0, the position of the inner circumferential surface 31f1 of the elastic crawler 31 is not displaced with respect to the sensor 4a. Therefore, it can be known from the information S acquired by the sensor 4a that the inner circumferential surface 31f1 of the elastic crawler 31 and the outer circumferential surface 34f1 of the drive wheel 34 are in contact with each other without a gap therebetween. On the contrary, in the present embodiment, when ΔD>0, the position of the inner circumferential surface 31f1 of the elastic crawler 31 is displaced with respect to sensor 4a in a direction away from the sensor 4a. Therefore, it can be known from the information S acquired by the sensor 4a that the inner circumferential surface 31f1 of the elastic crawler 31 and the outer circumferential surface 34f1 of the drive wheel 34 are separated from each other with a gap formed therebetween.
Next, in step 102, it is monitored whether the measured value D measured based on the information S is a preset predetermined value Dv or more.
As described above, the information S acquired by the sensor 4a is information on the distance (gap) D1 between the inner circumferential surface 31f1 of the elastic crawler 31 and the outer circumferential surface 34f1 of the drive wheel 34. For example, when the information S is information used to measure the distance D1, a predetermined value Dv1 is used as a predetermined value Dv. The predetermined value Dv1 is used to determine whether the distance D1 between the inner circumferential surface 31f1 of the elastic crawler 31 and the outer circumferential surface 34f1 of the drive wheel 34 is a gap that can cause jumping.
When the distance D1 is less than the predetermined value Dv1 (D1<Dv1), it is determined that there is a gap with which the drive pins 34b of the drive wheel 34 does not ride over the drive projections 31b of the elastic crawler 31. In other words, when D1<Dv1, it is determined that the distance D1 is a narrow gap that does not cause jumping. Therefore, in this case, it is determined that jumping does not occur, and the process returns to step 101.
On the other hand, when the measured value D is the predetermined value Dv or more (D≥Dv), it is determined that the drive pins 34b of the drive wheel 34 can ride over the drive projections 31b of the elastic crawler 31. In this example, when the distance D1 is the predetermined value Dv1 or more (D1≥Dv1), it is determined that there is a gap with which the drive pins 34b of the drive wheel 34 can ride over the drive projections 31b of the elastic crawler 31. In other words, when D1≥Dv1, it is determined that the distance D1 is a wide gap that can cause jumping. Therefore, in this case, it is determined that jumping may occur, and the process proceeds to step 103 to take a countermeasure to prevent the jumping. An example of the countermeasure may include a countermeasure to reduce or stop the rotation of the drive wheel 34 under control of the drive member 4c. Further, an example of the countermeasure may include a countermeasure to notify through the notification member 4d that the measured distance D1 is the predetermined value Dv1 or more, that is, jumping may occur. Alternatively, the operations of the drive member 4c and the notification member 4d can be used together.
Particularly, according to the present embodiment, the information S acquired by the sensor 4a in step 101 indicates the positional displacement ΔD of the inner circumferential surface 31f1 of the elastic crawler 31 when the inner circumferential surface 31f1 of the elastic crawler 31 is displaced with respect to the sensor 4a as described above. In step 102, the displacement ΔD measured based on the information S is set as the measured value D and the predetermined value Dv2 is used. In step 102, it is monitored whether the displacement ΔD is the preset predetermined value Dv2 or more. In this example, the predetermined value Dv2 is used to determine whether the displacement ΔD of the inner circumferential surface 31f1 of the elastic crawler 31 is a displacement that can cause jumping.
When the displacement ΔD is less than the predetermined value Dv2 (ΔD<Dv2), it is determined that the position of the inner circumferential surface 31f1 of the elastic crawler 31 is hardly displaced with respect to the sensor 4a. In other words, when ΔD<Dv2, as in the case where the distance D1 is considered as a gap between the inner circumferential surface 31f1 of the elastic crawler 31 and the outer circumferential surface 34f1 of the drive wheel 34, it is determined that the drive pins 34b of the drive wheel 34 do not ride over the drive projections 31b of the elastic crawler 31. Therefore, in this case, it is determined that jumping does not occur, and the process returns to step 101.
On the other hand, when the displacement ΔD is the predetermined value Dv2 or more (ΔD≥Dv2), it is determined that the drive pins 34b of the drive wheel 34 can ride over the drive projections 31b of the elastic crawler 31. In other words, when ΔD≥Dv2, it is determined that the displacement ΔD of the inner circumferential surface 31f1 of the elastic crawler 31 is a large displacement that can cause jumping. Therefore, in this case, it is determined that jumping may occur, the process proceeds to step 103 to take a countermeasure to prevent the jumping. As the countermeasure, the rotation of the drive wheels 34 can be reduced or stopped under control of the drive member 4c, as in the case where the distance D1 is considered. Further, as the countermeasure, it is possible to notify through the notification member 4d that the displacement ΔD as the measured distance is the predetermined value Dv2 or more, that is, jumping may occur. Alternatively, the operations of the drive member 4c and the notification member 4d can be used together.
The crawler monitoring method according to the present embodiment is executed when the information S acquired by the sensor 4a is input to the monitoring member 4b. In the present embodiment, a sampling frequency (Hz) at the time of acquiring the information S from the sensor 4a can be 1 Hz or more. Preferably, the sampling frequency (Hz) is equal to the number of times the drive projections 31b of the elastic crawler 31 pass through the sensor 4a per unit time. In this case, all of the drive projections 31b of the elastic crawler 31 can be monitored. For example, when the number of times the drive projections 31b of the elastic crawler 31 pass per unit time is 30 Hz, the sampling frequency is 30 Hz. More preferably, the sampling frequency (Hz) is an integral multiple of the number of times the drive projections 31b of the elastic crawler 31 pass per unit time. In this case, more detailed monitoring can be performed. For example, when the number of times the drive projections 31b of the elastic crawler 31 pass per unit time is 30 Hz, the sampling frequency can be 60 Hz or 90 Hz which is an integral multiple of 30 Hz.
In the crawler monitoring system 4, the sensor 4a may communicate with the monitoring member 4b in a wired or wireless manner, the monitoring member 4b may communicate with the drive member 4c in a wired or wireless manner, and the monitoring member 4b may communicate with the notification member 4d in a wired or wireless manner.
Examples of a power supply for the crawler monitoring system for the crawler monitoring system 4 may include a vehicle power supply (vehicle battery) mounted on the vehicle body 2 and an external power supply separately provided for the crawler monitoring system 4. However, as the power supply for the crawler monitoring system, the vehicle power supply is preferably used. In this case, the crawler monitoring system 4 can be activated at the same time when the power is supplied to the vehicle. In addition, when the external power supply is used, the power to be supplied to the crawler monitoring system 4 is limited, and it is necessary to replace the external power supply. However, when the vehicle power supply is used, since a battery is charged during use of the vehicle, it is not necessary to replace the power supply as a power supply for the crawler monitoring system.
In order to confirm data at a later date, the crawler monitoring system 4 can save the data in the storage member 4b2. Alternatively, the crawler monitoring system 4 may further include a storage medium such as a data logger independent of the storage member 4b2. In this case, the data can be saved in the storage medium.
Referring to
In the crawler monitoring system 4, when determining that the measured value D (D1, ΔD) is the predetermined value Dv (Dv1, Dv2) or more, the monitoring member 4b reduces or stops the rotation of the drive wheels 34 under control of the drive member 4c, or notifies through the notification member 4d that the measured value D (D1, ΔD) is the predetermined value Dv (Dv1, Dv2) or more. In this case, the jumping can be prevented in advance by the control of the rotation of the drive wheels 34 or the advance notification of the jumping for the purpose of preventing the jumping.
Referring to
Referring to
In the crawler monitoring system 4, the sensor 4a preferably includes a plurality of sensors disposed in the crawler circumferential direction. In this case, the behavior of the inner circumferential surface 31f1 of the elastic crawler 31 is monitored in more detail, and thus jumping can be detected in advance with higher accuracy.
Referring to
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In the crawler vehicle 1, the sensor 4a is preferably provided in at least one crawler apparatus having a large applied load of the crawler apparatus 3 on the vehicle front side and the crawler apparatus 3 on the vehicle rear side. In this case, it is possible to detect jumping in the crawler apparatus 3, which tends to cause jumping, in advance. For example, when the crawler vehicle 1 is a tractor, a working machine called an implement is attached to the vehicle rear side to pull. In this case, a large load is applied to the rear side of the crawler vehicle 1. Accordingly, in this case, the sensor 4a is preferably provided at least the crawler apparatus 3 on the vehicle rear side.
In the crawler vehicle 1, the sensor 4a is preferably provided in every crawler apparatus 3. In this case, jumping in all of the four crawler apparatuses 3 can be detected in advance. Referring to
The crawler monitoring method described with reference to
The crawler monitoring method described with reference to
The crawler monitoring method described with reference to
Referring to
According to the present disclosure, it is possible to provide the crawler monitoring system, the crawler apparatus, the crawler vehicle, and the crawler monitoring method capable of preventing the jumping in advance. Further, according to the present disclosure, the countermeasure is taken to prevent the jumping in advance, and thus it is possible to eliminate downtime of the crawler apparatus 3 and the crawler vehicle 1 including the crawler apparatus 3 caused by repairs of the damaged drive projections 34b.
Although the exemplary embodiment of the present disclosure has been described above, various changes can be made without departing from the scope of claims. As described above, the term “crawler monitoring system” in the present disclosure is synonymous with the “crawler monitoring device”. The crawler vehicle 1 is applicable to an agricultural machine (for example, a tractor or a combine). In addition, the crawler vehicle 1 is applicable to a construction machine (for example, an excavator, a dump car, a crane truck, or an aerial work platform).
Number | Date | Country | Kind |
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2020-149691 | Sep 2020 | JP | national |