Tension monitor for chassis tracks in working machine

Abstract

A working machine (100), such as a tractor or skid loader, has a motion sensor (204) attached to a segment (132) of a continuous ground engaging track (110) in a chassis (105). A motion sensor (204) generates motion data indicative of a change in motion of the track segment as the track (110) rotates about the track assembly (108). An electronic controller (102) of the work machine (100) receives and evaluates the motion data, first identifies a position of the track segment (132) within the chassis (105), and then compares the motion data to expected motion data of the track segment (132) under normal track tension. The movement data exceeding the expected movement data range indicates an abnormal sag of the track (110), causing the electronic controller (102) to generate an alert to adjust track tension.

Description

Technical Field

[0001] This invention relates to a tension monitor for chassis tracks in a work machine. More specifically, this invention relates to a monitoring system that uses electronic motion sensors located within the tracks to detect tension changes within the ground tracks of the work machine. Background Technology

[0002] Working machines such as tractors, skid steer loaders, bulldozers, and excavators typically have continuous ground-engaging tracks on the left and right sides of the machine within its chassis. These tracks help provide traction to propel the machine and are usually composed of interconnected links linked together by pins to form a loop chain. Depending on the implementation, track plates within the tracks may have spikes to further enhance ground traction. Drive sprockets on the machine have teeth that engage with the chain, causing the tracks to rotate around one or more idler pulleys and track rollers, thus enabling the machine to move forward or backward.

[0003] For the machine to operate effectively, the track needs to maintain proper tension around the drive sprocket and idler pulley. Excessive track slack (potentially due to wear and tear on the track engagement components over time) can cause the track to slip off the drive sprocket or idler pulley. Replacing the track will cause machine downtime, resulting in costly losses and significant disruption. Conversely, insufficient track slack can subject the engagement components to stress and wear, leading to premature machine failure. Therefore, track tension needs to be monitored regularly and adjusted as necessary.

[0004] U.S. Patent No. 7,172,257 (“'257 Patent”) describes a method for monitoring track tension in a working machine. '257 Patent describes a track tension adjustment device comprising a tension adjustment cylinder driven by a hydraulic pump. A hydraulic sensor detects hydraulic pressure in the tension adjustment cylinder, which is coupled to the track. Deviations from a specified pressure range indicate a change in track tension, which is then adjusted by moving an idler wheel using the hydraulic pump. Among other things, by inferring track tension from the hydraulic pressure of an auxiliary pump, '257 provides an imprecise method for determining track tension, which may delay accurate identification of tension problems.

[0005] The examples of this invention are intended to overcome the shortcomings of such systems. Summary of the Invention

[0006] In one aspect of the invention, a system for monitoring the tension of an annular track of a machine includes a drive sprocket having teeth around a circular outer circumference; an idler wheel having an outer circumference; and an annular track engaging the teeth and the outer circumference to move at least across a span between the drive sprocket and the idler wheel. A motion sensor is attached to a segment of the annular track and configured to generate track data indicating changes in the motion of the motion sensor across the span. The system further includes a memory configured to store target data representing expected changes in the motion of the motion sensor across the span; and a controller configured to determine that the track data is outside the range of the target data. An actuator is configured to generate an alarm when the track data is outside the range of the target data.

[0007] In another aspect of the invention, a working machine includes an engine configured to provide propulsion for the working machine; and a chassis coupled to the engine for engaging the ground to move the working machine. The chassis includes a drive sprocket, an idler wheel, and a ground-engaging track engaged with the drive sprocket and idler wheel for movement at least over a span between the drive sprocket and idler wheel. Furthermore, the chassis has a motion sensor attached to a section of the ground-engaging track. The motion sensor is configured to generate tension data to indicate changes in motion of the motion sensor over the span. The working machine further includes a memory configured to store target data representing expected changes in motion of the motion sensor over the span; and an electronic controller communicatively coupled to the motion sensor. The electronic controller is configured to receive the tension data and to indicate an alarm when the tension data is outside the range of the target data.

[0008] In another aspect of the invention, a computer-implemented method for monitoring the tension of tracks within the chassis of a working machine is disclosed. The method includes receiving motion data from motion sensors within a track segment by a processor during track rotation around a track assembly within the chassis. The processor then compares a portion of the motion data indicating when the track segment is at a predetermined position offset from a drive sprocket with target motion data stored in a memory for that predetermined position. The method includes determining that the portion of the motion data does not match the target motion data and generating an alarm related to track tension. Attached Figure Description

[0009] Figure 1 This is a schematic side view of an exemplary tracked machine according to an example of the present invention.

[0010] Figure 2 It is an example of a tension detector according to the present invention. Figure 1 A partial schematic diagram of the chassis of the tracked machine shown.

[0011] Figure 3 This is an example according to the present invention. Figure 1 An exploded isometric view of an exemplary portion of the track assembly of the tracked machine shown.

[0012] Figure 4 Within the tension monitoring system according to an example of the present invention Figure 2 A partial side view of an exemplary track link is shown.

[0013] Figure 5 It is a description of monitoring according to an example of the present invention. Figure 1 The flowchart shows a method for adjusting the track tension of a tracked machine. Detailed Implementation

[0014] According to the principles of the present invention, a working machine with a chassis having ground-engaging tracks includes a tension detector attached to a track segment. The tension detector includes motion sensors configured to generate data indicating changes in motion of the continuous track during rotation of a track assembly within the chassis. An electronic controller, whether within the tension detector or elsewhere, can evaluate the motion data to determine the position of the track segment at a given moment and compare the changes in track segment motion with historical data stored in a memory. If there is a discrepancy between the track segment motion data and historical data indicating a properly tensioned track, the electronic controller can alert the working machine operator that track adjustment is needed. Several examples of implementing the principles of the invention are described below. Wherever possible, the same reference numerals are used in all figures to denote the same or similar parts.

[0015] Figure 1 An exemplary tracked machine 100 consistent with examples of the present invention is shown. Tracked machine 100 can embody any machine that is driven, propelled, positioned, and / or manipulated by operating a “continuous” or annular tracked traction device. Such machines can include, for example, tracked tractors, skid steer loaders, bulldozers, excavators, backhoe excavators, tracked loaders, front shovels, rope shovels, or any other type of tracked maneuvering machine. Therefore, machine 100 typically includes working tools (not shown) for assisting in the performance of functions. For example, machine 100 can move auxiliary tools as needed, such as loaders, buckets, pallet forks, brooms, grinders, tillers, rakes, blades, or augers, etc.

[0016] Machine 100 typically includes an upper body 101 supported by a chassis 105. The upper body 101 includes a cab 106 configured to house the operator of the machine 100. As discussed further below, the cab 106 may include a workstation with various human-machine interfaces, such as controls, instruments, and indicators, for operating the machine 100 and receiving feedback on its behavior. An electronic control module (ECM) 102 and a communicator 103, discussed in more detail below, may be located within the upper body 101 and receive, process, and transmit electronic information related to the performance and configuration of the machine 100, some of which may be useful to the operator within the cab 106.

[0017] The upper body 101 further includes an engine 104. An engine, also known as a power source, generates and transmits mechanical power for various functions of the machine 100, such as the power required to propel the machine 100 and operate its various actuators and systems. Typically, engine 104 is an internal combustion engine, such as a diesel engine, a gasoline engine, an electric-gas hybrid engine, or any other configuration known to those skilled in the art. Alternatively or additionally, drive mechanism 122 may be embodied as an electric motor electrically connected to a power source and configured to convert at least a portion of electrical energy into mechanical energy. According to yet another example, engine 104 may include a hydraulic motor fluidly connected to a hydraulic pump and configured to convert pump-pressurized fluid into torque output. Other features of the engine may include a fuel system, an exhaust system, and a cooling system, which are not included in the illustrations and discussion for simplicity.

[0018] exist Figure 1 In the example, an engine 104 within the upper body 101 propels the machine 100 by moving at least one track assembly 108 within the chassis 105. As a right-side view, Figure 1 Only a single track assembly 108 is shown. Typically, at least one second track assembly corresponding to track assembly 108 is also located on the left side of machine 100. Typically, track assembly 108 includes track 110, drive sprocket 112, front idler sprocket 114, rear idler sprocket 116, multiple track rollers 118, and frame assembly 120. These components of track assembly 108 are merely exemplary and not intended to be limiting. Therefore, track assembly 108 may include additional and / or different components beyond those listed above.

[0019] The engine 104 of machine 100 sends power to drive sprocket 112 via drive mechanism 122. Drive mechanism 122 may include mechanical drive, hydraulic drive, electric drive, or a combination thereof. Drive sprocket 112 may be coupled to drive mechanism 122 via a shaft (not shown), which provides an interface for transmitting torque generated by engine 104 and drive mechanism 122 to drive sprocket 112, causing it to rotate. For example, drive sprocket 112 may be fixed (e.g., welded, bolted, thermally joined, etc.) to a hub associated with a shaft (not shown) so that drive sprocket 112 rotates in response to torque generated by drive mechanism 122. In some examples, drive sprocket 112 may be coupled directly to drive mechanism 122 via drive shaft. Alternatively, drive sprocket 112 may be coupled to drive mechanism via torque converter (such as gearbox, transmission, etc.) such that the rotation of drive sprocket 112 is proportional to the torque generated by drive mechanism 122.

[0020] The track 110 forms a continuous or annular loop structure, serving as the ground engagement portion of the machine 100. The track 110 is operatively coupled to a drive sprocket 112, a front idler 114, a rear idler 116, and track rollers 118. Typically, rotation of the drive sprocket 112 causes the track 110 to move around the outer periphery or circumference of the drive sprocket 112, the first idler 114, the track rollers 118, and the rear idler 116 to engage the ground, thereby propelling the machine 100 in a manner known in the art. Figure 1 The clockwise rotation of the central drive sprocket 112 and the track 110 will cause the machine 100 to move forward (along... Figure 1 The X-axis in the diagram is from left to right, while Figure 1 The counterclockwise rotation of the central drive sprocket 112 and the track will cause the machine 100 to move backward (along...). Figure 1 The -X axis in the diagram is from right to left.

[0021] In one example, track 110 includes a chain 123 formed by a plurality of interconnected track links 124. It should be understood that, as used herein, "track link" refers to any linking component of a continuous chain of a tracked machine. In one example, adjacent (e.g., consecutive) track links 124 may be coupled together via a plurality of track pin assemblies, further described below. Track links 124 engage with teeth 126 of drive sprocket 112 to drive the chain 123 of track 110 around drive sprocket 112, front idler sprocket 114, rear idler sprocket 116, and track roller 118. Figure 1 In the example, the length of track 110 is typically determined by the path of drive sprocket 112, front idler 114, track roller 118 and rear idler 116 around machine 100.

[0022] The track 110 within the track assembly 108 may include a plurality of track plates 128. Each track plate 128 may include a connecting portion configured to be secured to one or more track links 124, and a ground engagement portion configured to contact the ground. The ground engagement portion may include one or more features (e.g., spikes) to increase traction between the track plate 128 and the ground. However, it should be understood that any type of track plate forming part of the track assembly used in a tracked mobile machine can be implemented according to the invention. In some examples, the track plate 128 may be integrally formed with the track links 124. In other embodiments, the track plate 128 may be completely omitted from the track assembly 108, such that the surface of the track links 124 that would otherwise contact the track plate 128 can contact the ground below the machine 100.

[0023] As is known to those skilled in the art, when the track 110 is mounted within the machine 100, it is under tension, which may vary over time. For example, the radii of the front idler 114 and the rear idler 116 may decrease due to metal-to-metal contact with the track links 124 or due to contact with abrasive debris in the environment. As these components wear, the circumferential track of the track 110 around the front idler 114 and the rear idler 116 decreases. Similarly, due to the same interactions, the radial thickness or height of the track links 124 may decrease, thereby increasing the internal circumferential length of the track 110 accordingly. These changes reduce the tension of the track 110, causing it to sag between the drive sprocket 112 and the front idler 114 (when traveling forward) and between the drive sprocket 112 and the rear idler 116 (when traveling backward).

[0024] Frame assembly 120 provides a housing for the components attached to and operated by the front idler sprocket 114, rear idler sprocket 116, and track roller 118. Additionally, in some examples, frame assembly 120 includes a track tension actuator 130. The track tension actuator 130 within frame assembly 120 is configured to adjust the sag and tension of track 110 by moving the front idler sprocket 114 away from or towards the rear idler sprocket 116. In other words, by adjusting the displacement using track tension actuator 130, the circumferential trajectory of chain 123 around drive sprocket 112, front idler sprocket 114, and rear idler sprocket 116 can be increased or decreased, thereby modifying the tension of track 110 to substantially match the internal circumferential length of chain 123.

[0025] In some examples, the track tension actuator 130 is a grease cylinder that extends to push the front idler 114 away from the rear idler 116 when grease is manually filled (i.e., along...). Figure 1 (X-axis in the middle). Conversely, when the grease is removed, the track tension actuator 130, which acts as a grease cylinder, tends to allow the front idler wheel 114 to move toward the rear idler wheel 116 (i.e., along the X-axis). Figure 1(X-axis in the image). Alternatively, actuator 28 may be a hydraulic cylinder having one or more chambers that are automatically filled with fluid pressurized by an on-board source, the pressurized fluid acting on the piston / rod assembly to move the front idler wheel 114. Other manual, automatic, linear, and / or rotary configurations of track tension actuator 130 may be considered, or alternatively, as needed.

[0026] While the tension of track 110 may decrease over time due to wear, adjusting it using track tension actuator 130 may also result in excessive tension on track 110. Sagging between drive sprocket 112 and front idler pulley 114 can be eliminated, thereby tautning chain 123. In this situation, track 110 may exert stress on its supporting components, such as drive sprocket 112, leading to undesirable wear and deterioration. Therefore, track tension actuator 130 needs to be readjusted to move the relative positions of front idler pulley 114 and rear idler pulley 116 to achieve acceptable tension on track 110 based on the operation of machine 100.

[0027] According to the principles of the present invention, in order to aid in the detection and adjustment of the tension of the track 110, at least a portion of the track 110 may be configured as a sensing segment 132. In such a way... Figure 1 In some of the examples shown, sensing segment 132 includes a track link or track plate that is positioned between drive sprocket 112 and front idler sprocket 114 as the machine 100 moves forward (i.e., traverses along the X-axis). In some examples, sensing segment 132 includes one or more electronic devices capable of and configured to detect its movement, thereby allowing the derivation of the spatial location of sensing segment 132, as described below. Figure 2-4 Further discussion.

[0028] Figure 2 yes Figure 1 A partial schematic diagram of the chassis 105 of the machine 100 is depicted. For the purposes of discussion, a portion of the track 110 extending between the drive sprocket 112 and the front idler sprocket 114 has been removed and replaced with a generalized illustration of the chain 123 with different tension values ​​in three cases. Figure 2 In the first case, marked "A", chain 123 has the expected tension suitable for operating conditions and machine 100, indicated by a slight sag between drive sprocket 112 and front idler sprocket 114. Figure 2 In the second case, marked "B", the chain 123 has almost no slack or sagging between the drive sprocket 112 and the idler sprocket 114, indicating a high tension in the track 110. Figure 2 In the third case marked "C", chain 123 is excessively slack or sagging, indicating low tension.

[0029] like Figure 2 Typically, the tension detector 202 can be located within the sensing segment 132 of the chain 123 (see [reference]). Figure 1 Tension detector 202 is an electronic circuit containing one or more components capable of and configured to sense changes in the motion of the device. Typically, tension detector 202 includes at least one motion sensor 204 to identify and process various motion modes, such as acceleration, vibration, impact, tilting, or rotation. In one example, motion sensor 204 is a MEMS (microelectromechanical system) component, which typically uses differential capacitors to detect one or more motion modes. Figure 2 As shown, the tension detector 202 can be configured as a circuit board containing a motion sensor 204 and associated electronic components, including a communication device 206 for interacting with a processing device such as ECM 102, and a battery 208 for powering the electronic components on the tension detector 202.

[0030] In some examples, the motion sensor 204 within the tension detector 202 is a MEMS gyroscope configured to detect the sensor's angular rate of motion, i.e., rotation. As the machine 100 moves forward (i.e., along the X-axis), the chain 123 disengages from the drive sprocket 112, and the sensing segment 132 moves downward (i.e., along the X-axis). Figure 1 and Figure 2 When the Z-axis (in the chain) is oriented towards the front idler wheel 114, it will experience a motion angular rate. The degree or rate of this angular motion will vary based on the amount of sag of the chain 123, i.e., based on the tension of the track 110. For example, in Figure 2 In case A, chain 123 has what could be called optimal or desired tension, with a slight sag between drive sprocket 112 and front idler sprocket 114. As tension detector 202 moves away from drive sprocket 112, the motion rate of motion sensor 204 will change according to the expected amount. Conversely, in case B, where chain 123 is taut and there is almost no sag between drive sprocket 112 and front idler sprocket 114, the motion rate of motion sensor 204 will be smaller than in optimal case A. Similarly, in case C, where chain 123 is slack and there is a large sag between drive sprocket 112 and front idler sprocket 114, the motion rate of motion sensor 204 will be larger than in optimal case B. Therefore, motion sensor 204 within tension detector 202 provides an indication of relative sag within chain 123, which can be used to determine whether track 110 is at the preferred tension for maintaining engagement and minimizing wear within track assembly 108, or whether adjustment using track tension actuator 130 is required.

[0031] The motion sensor 204 can also use other types of detection to provide an indication of relative slack in the chain 123. For example, the motion sensor 204 could be an accelerometer (which detects linear motion as a change in velocity per unit time) or a vibration sensor. For example, a triaxial MEMS accelerometer could sense the rotation or tilt of its position in space, and thus also sense the position of the tension detector 202, thereby providing a basis for the travel path of the sensing segment 132 after it leaves the drive sprocket 112, whether it is situation A, situation B, situation C, or other tension conditions.

[0032] In addition to providing motion data indicating chain 123 sag, motion sensor 204 can also be used by machine 100 to determine the position of sensing segment 132 within chassis 105. As described above, when machine 100 moves forward and sensing segment 132 is located between drive sprocket 112 and front idler sprocket 114, the assessment of chain 123 sag or slack is most representative of the tension of track 110. In some examples, data from motion sensor 204 can be used to identify when the sensor is in that position. For example, using a gyroscope as motion sensor 204, motion angular rate data from motion sensor 204 can be compared with previously captured motion angular rate data of the device during its traverse around chassis 105. For example, data indicating moderate and repetitive angular changes can indicate that motion sensor 204 is passing through the path of track roller 118. For example, data indicating abrupt changes in angular motion can indicate that motion sensor 204 is moving around one of the wheels, namely drive sprocket 112, front idler sprocket 114, or rear idler sprocket 116. Motion data of the sensor segment 132 moving along a circular path within the chassis 105 can be collected and stored, and used as a template or standard to compare with new motion data, thereby identifying the position of the sensor segment 132 within the chassis 105 at any point in time, especially when the motion sensor 204 passes the drive sprocket 112 and moves forward idler 114.

[0033] In some examples, the tension detector 202 stores data related to a target sag curve of the chain 123 in the span between the drive sprocket 112 and the front idler sprocket 114 in a memory (not shown) for comparison with new data from the motion sensor 204. The target sag curve may correspond to a preferred amount of sag of the chain 123 in that span to avoid track slippage and excessive wear of the equipment within the track assembly 108. Although Figure 2Case A provides an example of a potential target sag curve, but the target sag curve may vary based on the characteristics, size, service life, and intended use of machine 100. Tension detector 202 can evaluate incoming motion data from motion sensor 204 based on the position determination of sensing segment 132, and compare the incoming motion data at the appropriate position of motion sensor 204 with predetermined and stored target sag data to determine whether track 110 meets the tension requirements.

[0034] To perform this data processing, the tension detector 202 may include circuitry configured to generate, receive, transmit, and / or modify signals and data indicative of motion detected by the motion sensor 204, as discussed above. For example, although Figure 2 Motion sensor 204 is shown, but other circuit components not shown may include signal conditioners, amplifiers, multiplexers, and / or converters (e.g., analog-to-digital (A / D) converters or digital-to-analog (D / A) converters). A controller (not shown), such as a low-power microcontroller, may process inputs received from motion sensor 204 and / or a memory device (not shown). The memory device may be any one or both of random access memory (RAM) and read-only memory (ROM), and may store information related to one or more inputs received from motion sensor 204, such as data related to the position of sensing segment 132 on its path around chassis 105, target sag curves, or incoming motion data. Alternatively or additionally, the memory device may store instructions used by one or more other components of tension detector 202 or by the controller.

[0035] like Figure 2 As indicated, the tension detector 202 includes a power source in the form of a battery 208 in one example. In other examples, the power source may alternatively or additionally include motion-based energy (such as a vibration-based energy harvesting system) to power one or more components of the tension detector 202, and / or may be used to charge the battery 208. In yet another example, the battery 208 is capable of wireless charging (e.g., near-field charging). In this way, the tension detector 202 can be embedded within the sensing segment 132 while being able to receive power from outside the track 110, thereby reducing the need for an onboard battery. It should be understood that these components are exemplary, and additional and / or alternative circuit components may be used depending on the configuration of the tension detector 202.

[0036] Although Figure 2Examples of specific components used in the tension detector 202 are shown, but the tension detector 202 is not limited to the configuration shown. Rather, consistent with the disclosure, the tension detector 202 may include other components, more components, or fewer components than described above. Furthermore, it is conceivable to implement one or more of the hardware components listed above, partially or entirely, using software. One or more such software components may be stored on a tangible, non-transitory computer-readable storage medium comprising computer-executable instructions that, when executed by a processor or other computer hardware, can perform methods and processes consistent with the disclosure.

[0037] Although Figure 2 The mounting of motion sensor 204 on the circuit board of tension detector 202 is schematically shown, but at least one tension detector 202 may further be mounted within or on sensing segment 132. In some examples, tension detector 202 is fixed to the outer surface of sensing segment 132. In other examples, tension detector 202 is at least partially embedded in the body of sensing segment 132, as described below. Figure 3 and Figure 4 Further explanation.

[0038] Figure 3 This is an exploded view of a representative sensing segment 132 that forms part of the track 110. Figure 3 The sensing segment 132 includes four track links 124, a track pin assembly 302, and a track plate 128. For example... Figure 3 As shown, track links 124 may include track links 124A and track links 124B, which may be mirror images of each other and are disposed on opposite sides of track assembly 108. Therefore, track link 124A forms one side of track assembly 108 (e.g., Figure 3 The track assembly 108 is located on the side closer to the center of machine 100 and further along the Y-axis, while the track link 124B forms the opposite side of the track assembly 108 (e.g., the side of the track assembly further away from the center of machine 100).

[0039] Figure 3 The components shown can be assembled to form sensing segment 132. Specifically, a track pin assembly 302 can be used to connect four track links 124 (e.g., two track links 124A and two track links 124B). A track plate 128 can be connected to one track link 124A and one track link 124B. Another track plate 128 (not shown) can be connected to another track link 124A and another track link 124B.

[0040] Each track link 124 includes an inward-facing surface 304 and an outward-facing surface 306. The inward-facing surface 304 may be oriented towards the center of the chain 123 (e.g., towards a track link on the opposite side). Conversely, the outward-facing surface 306 may be oriented away from the center of the chain 123. Figure 2 As shown, track links 124A can be interconnected such that the inward-facing surface 304 is connected to the outward-facing surface 306 of the adjacent track link 124A. Similarly, track links 124B can be interconnected such that the inward-facing surface 304 is connected to the outward-facing surface 306 of the adjacent track link 124B. However, it should be understood that other track link configurations are also possible.

[0041] like Figure 2 As shown, each track pin assembly 302 connecting track links 124 may include a track pin 308 and a bushing 310. The bushing 310 may be disposed on the track pin 308 such that the bushing 310 rotates relative to the track pin 308. With this arrangement, the drive sprocket 112 ( Figure 1 The teeth 126 of the track pin 308 can engage with the bushing 310. As the teeth 126 exert force on the bushing 310, the track pin 308 can translate along the X-axis, thereby causing the track 110 to move and the machine 100 to move accordingly on the ground, as is known in the art.

[0042] Each track link 124A and 124B may include one or more through holes 312, while each track plate 128 may include a corresponding through hole 314. Each track link 124A and 124B may also include one or more openings 316 aligned with the through holes 312. With this arrangement, threaded fasteners such as bolts (not shown) can be disposed within the through holes 312 and 314 to attach the track plate 128 to the track links 124A and 124B, and corresponding threaded fasteners such as nuts (not shown) can be disposed at the ends of the bolts. The openings 316 may be shaped to facilitate placement or tightening of the nuts at the ends of the bolts, such as by adjusting their size, shape, or position to accommodate tools that can be used to tighten the nuts.

[0043] Each of track links 124A and 124B may define a plurality of additional through holes 318, 320, configured to receive at least a portion of the track pin assembly 302 in a manner known in the art. For example, through hole 318 may be configured to receive a portion of bushing 310, and through hole 320 may be configured to receive a portion of the free end of track pin 308. In this way, a pivot joint can be formed at track pin assembly 302, allowing chain 123 to move freely about drive sprocket 112, front idler sprocket 114, rear idler sprocket 116, and track roller 118 during operation.

[0044] Depending on the implementation requirements, the tension detector 202 can be mounted on or inside any structure of the sensing segment 132. In some examples, the tension detector 202 is adhered to the surface of the chain 123, such as the inward-facing surface 304 or the outward-facing surface 306 of track links 124A or 124B. The selection of track links 124A, 124B that include the tension detector 202 can depend on many factors, such as the position of the track links in the track assembly 108 and their orientation relative to the machine 100, and how the tension detector 202 is mounted to the selected track links 124. For example, if any of the track links 124A includes the tension detector 202, the tension detector 202 will be positioned closer to the machine 100 than if any of the track links 124B includes the tension detector 202. Similarly, if the tension detector 202 is mounted on or near the inward-facing surface 304 or the outward-facing surface 306, the orientation of the selected track link 124 will determine whether the tension detector 202 faces or turns away from the machine 100. These factors can be taken into account when determining the location of the track link 124, including the tension detector 202, based on the implementation of the machine 100.

[0045] Since machine 100 can operate in harsh environments, tension detector 202 can be advantageously embedded within the cavity of chain 123 to protect it from damage. Figure 3 As depicted, in one possibility, the outward-facing surface 306 of track link 124B includes a cavity 322, sized sufficiently to receive and retain the tension detector 202. Depending on the implementation requirements, the cavity 322 can alternatively be placed in the inward-facing surface 304 or in track link 124A. Regardless of its location, the cavity 322 can be formed in the track link by machining or manufactured by casting, forging, or other methods. Figure 3 In an alternative embodiment, the track plate 128 within the sensing section 132 may include a cavity 324 for retaining the tension detector 202. The track plate 128, in contact with the ground, is subjected to traction forces as the track 110 rotates. Nevertheless, in some implementations, mounting the tension detector 202 in an embedded position along the side of the track plate 128, or in another location within the track plate 128, may be an acceptable option. In yet another option, the track pin 308 within the sensing section 132 may include a cavity 326 for retaining the tension detector 202. Although as... Figure 3 As shown, at the axial end of track pin 308, cavity 326 can be located on the radial side of track pin 308, or any convenient location suitable for this implementation. Any other structure within sensing section 132 is also sufficient to accommodate tension detector 202.

[0046] Tension detector 202 may be located within cavity 322 and retained in a permanent or removable configuration. In one possibility, a housing mechanism (not shown), such as potting epoxy resin, may be introduced into cavity 322 to protect and hold tension detector 202 in place after curing to form a solid material. The housing mechanism may be selected to provide sufficient strength and physical protection for tension detector 202 while allowing electrical communication using communication device 206. In another option, tension detector 202 may be retained within a housing configured to be removably or permanently mounted within cavities 322, 324, or 326, such as using threads, positioning mechanisms, clips, etc. In some examples, the housing mechanism may include a cover (not shown) configured to seal openings to cavities 322, 324, or 326. For example, tension detector 202 may be secured in place by fasteners (e.g., threaded fasteners), and the cover may enclose tension detector 202 within cavities 322, 324, or 326 to protect tension detector 202 from damage. Although different cavities and containment mechanisms are depicted and described in the figures, it should be understood that there may be other methods to mount the tension detector 202 on or inside the track link 124, track plate 128, or track pin 308.

[0047] In some examples, the components within the tension detector 202 are kept to a minimum to save space, power, and processing capacity within the track 110. Therefore, the tension detector 202 may primarily comprise the motion sensor 204, communication device 206, and battery 208, along with auxiliary electronic components. In this arrangement, the tension detector 202 transmits data received from the motion sensor 204 to a processing device located outside the track 110. In this configuration, the processing capability for motion data from the motion sensor 204 may be located outside the tension detector 202 within the machine 100.

[0048] Figure 4 This is a schematic diagram illustrating a portion of a tension monitoring system 400 in which the tension detector 202 communicates with other electrical and processing components in machine 100 to form the machine. Figure 4 To illustrate, track link 124B is isolated from sensing section 132, and the tension detector 202 shown is mounted within cavity 322. In this example, tension detector 202 is mounted within cavity 322 of the outward-facing surface 306 of track link 124B and is communicatively connected to ECM 102 on machine 100. As discussed above and as... Figure 2As shown, the tension detector 202 includes a communication device 206, which is capable of and configured to receive and transmit signals to and from the tension detector 202. In addition to the communication device 206, the tension detector 202 may include one or more components for transmitting information signals, such as an antenna, transceiver, or transmitter. These functional elements may be integrated into the communication device 206, the motion sensor 204, or other integrated circuits within the tension detector 202. In most cases, the tension detector 202 will communicate wirelessly using industry protocols, such as the Bluetooth communication standard.

[0049] ECM 102 typically includes an antenna configured to receive signals from other devices, as well as a processor and memory suitable for receiving and evaluating data generated by motion sensor 204. In some examples, ECM 102 is capable of wirelessly communicating with tension detector 202 using Bluetooth or a similar protocol. Therefore, motion data generated by motion sensor 204 can be received intermittently or continuously by ECM 102. Upon receiving this motion data, ECM 102 can process the data, along with other machine data accessible to ECM 102, to determine positional parameters of sensing segment 136, such as its position within chassis 105 along track 110, its angular rate of change if motion sensor 204 is a gyroscope, its spatial position if motion sensor 204 is an accelerometer, its vibration frequency if motion sensor 204 is a vibration sensor, or other possible data. Alternatively, an onboard computer may be located within the dashboard of cab 106 and is adapted to wirelessly communicate with communication device 206 within tension detector 202. There may be other options within machine 100 for processing the data generated by motion sensor 204, as will be understood by those skilled in the art.

[0050] For example Figure 4 As shown, ECM 102 can additionally or alternatively share at least the motion data generated by motion sensor 204 with computing system 402 located remotely from machine 100. ECM 102 can communicate directly with a non-airborne computing system (such as computing system 402), or machine 100 can route communication via communicator 103 for longer-distance connectivity. Computing system 402 can be one or more servers, computers, or other non-airborne computing devices. For example, when machine 100 is located on a construction site, computing system 402 can be located in a back office or other location remote from machine 100, or remote from the entire construction site. Figure 4 As shown, the computing system 402 can wirelessly communicate with at least machine 100 via network 404.

[0051] Regardless of whether the motion data processing is performed in tension detector 202, ECM 102, computing system 402, or elsewhere, the processing can determine whether the tension of track 110 is within acceptable limits. It will be apparent to those skilled in the art that the received motion data can be compared with stored data related to the target sag curve to determine whether the sag of chain 123 over drive sprocket 112 when machine 100 moves forward is within acceptable limits. For example, when sensing segment 132 is in the horizontal direction (i.e., in...) Figure 1 and Figure 2 When the sensing segment 132 (along the X-axis) is at a predetermined distance from the top of the drive sprocket 112, this process can at least partially determine the vertical position of the sensing segment 132 relative to the top of the drive sprocket 112 (i.e., at...). Figure 1 and Figure 2 (along the Z-axis). In some examples, this vertical position is compared to an acceptable vertical position value at the corresponding stored horizontal position, which may correspond to the target sag curve. If the vertical position exceeds the acceptable tolerance range of the acceptable vertical position, the processing device can conclude that the tension of the track 110 needs to be adjusted. Obviously, the "acceptable" position or behavior of the motion sensor 204 will depend on the characteristics of the machine 100 and how it is implemented.

[0052] In some examples, if it is determined that track 110 needs tension adjustment, machine 100 will provide an alarm to the operator. In some examples, the alarm may be a visual warning provided on the dashboard of cab 106, an audible sound played within cab 106, or another mechanism conveying the conclusion to the operator. The alarm may indicate that tension adjustment is needed, or alternatively, indicate whether the tension is too high or too low. Upon receiving the alarm, the operator can adjust the tension of track 110 using track tension actuator 130 in a conventional manner. Alternatively, machine 100 may include a device that automatically adjusts the hydraulic pressure within track tension actuator 130 based on motion data provided by motion sensor 204.

[0053] from Figure 1-4 The architecture of the machine 100 shown includes options for chassis track tension monitoring. Figure 5This is a flowchart of a representative method 500 for monitoring track tension using motion sensors located within the track. Process 500 is shown as a logic flowchart, where operations represent a sequence of operations that can be implemented in hardware, software, or a combination thereof. In a software context, these operations represent computer-executable instructions stored on one or more computer-readable storage media, which, when executed by one or more processors, will perform the operations. Typically, computer-executable instructions include routines, programs, objects, components, data structures, etc., that perform a specific function or implement a specific data type. The described order of operations is not intended to be construed as limiting, and any number of the operations can be combined in any order and / or in parallel to implement the process.

[0054] exist Figure 5 In step 502, example method 500 includes: during rotation of the track around the track assembly in the chassis, a processing device on the machine or other electronic controller or processor receives motion data from the track segment. Figure 1-4 As shown, for example, when track 110 rotates, a computer processor or controller embodied in ECM 102 can collect motion data from motion sensor 204 embedded or otherwise attached to sensing segment 132. Motion sensor 204 can be a MEMS gyroscope or MEMS accelerometer, for example, located within the circuit board of tension detector 202. Tension detector 202 is capable of sending signals to ECM 102 including the motion data generated by motion sensor 204. Alternatively, the processor or controller can be implemented within tension detector 202 itself.

[0055] In the second step of 504, the processing equipment determines the position of the track section relative to a reference point on the chassis. In some examples, the reference point on the chassis 105 of the machine 100 may be the vertical top of the drive sprocket 112 (i.e., along...). Figure 1 or Figure 2 The Z-axis (located at the 12 o'clock position of the circular drive sprocket 112) is where the chain 123 disengages from the tooth 126. For example, the ECM 102 can evaluate motion data received from the sensing segment 132 to identify a motion pattern consistent with the movement of the sensing segment 132 as it passes the top of the drive sprocket 112. The ECM 102 can then identify when the sensing segment 132 reaches the position of interest based on the speed of the track 110. As discussed above, this position of interest could be the position where the track 110 experiences maximum sagging between the drive sprocket 112 and the first idler pulley 114 as the machine 100 moves forward.

[0056] Figure 5Step 506 of the method involves comparing motion data at the location of interest with target data for that location. Therefore, after a controller (such as ECM 102) determines that sensing segment 132 has at least reached the location of interest (possibly the area of ​​maximum sag of track 110), ECM 102 can compare the motion data received from motion sensor 204 with stored data indicating acceptable motion of chain 123 at that location. It will be apparent to those skilled in the art that the data indicating acceptable motion at that location can be collected from previous trial runs or simulations of machine 100 and may vary based on the characteristics of machine 100, its intended use, and the environment.

[0057] After comparing the motion data with the stored data, in step 508, the processing device determines that the motion data at the location of interest does not match the target data for that location. The controller within ECM 102 or tension detector 202 may conclude that the received motion data indicates that the degree or type of motion of sensing segment 132 does not match the stored target data, either too high or too low. For example, the motion angular rate of motion of motion sensor 204 at the location of interest may be substantially higher than the acceptable motion angular rate for that location, i.e., exceeding the upper limit of the tolerance range, indicating that the chain 123 is too slack. Conversely, the motion angular rate received at the location of interest may be substantially lower than the expected or acceptable motion angular rate for that location, i.e., exceeding the lower limit of the tolerance range, indicating that the chain 123 is too tight. It should be understood that tolerance ranges, "substantially higher," and "substantially lower" may vary depending on the implementation of machine 100 and are within the scope of routine experimentation for those skilled in the art.

[0058] In the final step 510, the processing device generates an alarm for non-compliant track tension to the operator. If the ECM 102 or similar processing device concludes in step 508 that the motion data does not match the stored target data, the ECM 102 will at least issue an alarm to the operator of machine 100. The alarm can be visually displayed on the dashboard of cab 106 via an actuator (not shown), audibly sounded in cab 104, signaled to the off-board computing system 402, or otherwise indicated. Upon receiving the alarm, the operator can increase or decrease the tension of track 110 as needed using track tension actuator 130.

[0059] Those skilled in the art will understand that the principles of the invention are not limited to the specific examples discussed or shown in the figures. For example, while a tension detector has been shown and discussed for track 110 on one side of machine 100, a separate tension detector may also be used for additional tracks (including one or more tracks on the opposite side of machine 100). Furthermore, it should be understood that more than one tension detector may be used within track 110. While a monitor for monitoring track tension in the underframe of a working machine has been discussed in the context of slack between the drive sprocket and the front idler during forward movement, slack may also be assessed in other spans, such as slack between the drive sprocket and the rear idler during reverse movement. Moreover, while the invention relates to a chassis having a drive sprocket, a front idler, a rear idler, and track rollers, implementations with more or fewer track guide rollers are also contemplated. Furthermore, the disclosed principles are not limited to implementations on working machines with chain tracks. Any vehicle using annular tracks or belts as a propulsion device, or any other device using belt or chain drives and potentially experiencing tension variations, may benefit from the disclosed and claimed examples and technologies.

[0060] Industrial applicability

[0061] This invention provides a system and method for monitoring the tension of the chassis tracks of a work machine, thereby providing an opportunity to adjust track tension and prevent excessive wear. Work machines such as tractors or skid steer loaders have motion sensors attached to a section of a continuous ground-engaged track within the chassis. The motion sensors generate motion data indicating changes in the movement of the track section as the track rotates around the track assembly. The work machine's electronic controller receives and evaluates the motion data, first identifying the position of the track section within the chassis, and then comparing the motion data to expected motion data for the track section under normal track tension. Motion data exceeding the expected range indicates abnormal track sagging, triggering an alarm from the electronic controller to adjust track tension. Therefore, incorrect track tension can be automatically and accurately detected, corrected, and track slippage or chassis wear can be prevented.

[0062] As mentioned above Figure 1-5As shown, an example system for monitoring the tension of the annular track of machine 100 typically includes a drive sprocket 112, an idler pulley 114, and an annular track 110 engaged with the drive sprocket and idler pulley, the track moving at least over the span between the drive sprocket and the idler pulley. A motion sensor 204 is attached to a segment 132 of the annular track and configured to generate track data indicating changes in the motion of the motion sensor over the span. A memory is configured to store target data representing expected changes in the motion of the motion sensor 204 over the span, while a controller 102 is configured to determine when the track data is outside the range of the target data. When the track data is outside the range of the target data, an actuator generates an alarm to adjust the track tension.

[0063] In an example of the invention, motion sensor 204 may be a gyroscope, accelerometer, vibration sensor, or similar device for sensing changes in motion, providing precise indication of the path of chain 123 within track 110. When motion data is provided from motion sensor 204, electronic controller 102 may first identify the position of motion sensor 204 based on previously captured historical data stored in memory. Then, as the motion sensor passes a span where track 110 would typically sag, the electronic controller may compare the motion data with expected motion data for that span. When a deviation occurs, an alarm may indicate to the operator that the tension of track 110 needs to be adjusted, either tighter or looser. Automatic detection provides more accurate detection of tension deviations compared to visual inspection or hydraulic assessment. Automatic detection also enables periodic (such as at the start of each workday) safety checks of tension without interfering with the operator's daily operations, and may even simplify operations. Therefore, the tension of track 110 can be maintained at an appropriate level within machine 100, preventing dangerous slippage of chain 123 and premature wear of components of track assembly 108.

[0064] Unless explicitly excluded, the use of the singular to describe a component, structure, or operation does not preclude the use of multiple such components, structures, operations, or their equivalents. As used herein, the word "or" refers to any possible permutation of a set of items. For example, the phrase "A, B, or C" refers to at least one of A, B, or C, or any combination thereof, such as A; B; C; A and B; A and C; B and C; A, B, and C; or multiples of any item, such as A and A; B, B, and C; A, A, B, C, and C, etc.

[0065] Approximate terms are intended to include a range of values ​​for a function or result that does not change the disclosed structure or process. For example, the term "approximately" generally refers to a range of values ​​that a person skilled in the art would consider equivalent to or have the same function or result as the stated value. Similarly, the aforementioned word "substantially" means to a large extent, but not exactly the same form, manner, or degree, and that a particular element will have a range of configurations that a person skilled in the art would consider to have the same function or result. As an example, "substantially parallel" does not need to be exactly 180 degrees, but can also include minor variations of a few degrees depending on the context.

[0066] While aspects of the invention have been specifically shown and described with reference to the above embodiments, those skilled in the art will understand that various additional embodiments can be conceived by modifying the disclosed systems and methods without departing from the spirit and scope of the disclosure. Such embodiments should be understood to fall within the scope of the invention as defined by the claims and any equivalents.

Claims

1. A system for monitoring the tension of an annular track (110) of a machine (100), comprising: A drive sprocket (112) has teeth (126) around a circular outer periphery. The idler wheel (114) has an outer circumference; An annular track (110) engages with the teeth (126) and the outer circumference to move over at least the span between the drive sprocket (112) and the idler wheel (114); A motion sensor (204), which is attached to a segment (132) of the annular track (110), is configured to generate track data indicating changes in the motion of the motion sensor (204) over the span; A memory configured to store target data representing expected motion changes of the motion sensor (204) over the span; Controller (102), configured to determine that the track data is not within the range of the target data; as well as An actuator configured to generate an alarm in response to the track data not being within the range of the target data.

2. The system of claim 1, wherein the annular track (110) comprises a continuous chain (123) formed by track links (124) joined together by track pins (308), and the motion sensor (204) is attached to one of the track links (124).

3. The system according to claim 2, wherein the motion sensor (204) is embedded in a cavity (322) of one of the track links (124).

4. The system of claim 1, wherein the annular track (110) includes track plates (128) attached to the track links (124), the track links (124) being engaged together by track pins (308), and the motion sensor (204) being embedded in a cavity (324, 326) of one of the track plates (128) or one of the track pins (308).

5. The system according to claim 1, wherein the motion sensor (204) is a gyroscope and the track data includes the motion angular rate of the motion sensor (204).

6. The system of claim 1, wherein the motion sensor (204) is an accelerometer and the motion includes a change in the velocity of the motion sensor (204).

7. A computer-based method for monitoring the tension of tracks (110) within the chassis (105) of a working machine (100), comprising: During the rotation of the track (110) around the track assembly (108) in the chassis (105), the processor (102) receives motion data from the motion sensor (204) within the track (110) segment; The processor (102) compares the motion data portion indicating when the track segment is at a predetermined position offset from the drive sprocket (112) with the target motion data of the predetermined position stored in the memory; It was determined that the motion data portion did not match the target motion data; as well as An alarm related to the tension of the track (110) is generated.

8. The computer implementation method according to claim 7, further comprising: Based at least in part on the motion data, the processor (102) determines when the track segment is at the predetermined position.

9. The computer implementation method according to claim 8, wherein determining when the motion sensor (204) is located at the predetermined position comprises: Based on the motion changes indicated by the motion data, the processor (102) identifies when the track segment passes the drive sprocket (112).

10. The computer implementation method according to claim 7, further comprising: During the previous rotation of the track (110) around the track assembly (108), the processor (102) receives initial motion data from the motion sensor (204); At least some of the initial motion data are stored in the memory as the target motion data.

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