Chain measuring device, chain measuring system, and method for calculating chain slack

Abstract

To provide a chain measuring device capable of easily and accurately measuring a chain.SOLUTION: A chain measuring device (2) measures a slack amount of a chain wound around a sprocket. The measuring device includes a body part (5) having an acceleration sensor (22) capable of detecting acceleration in the direction of gravity, and a mounting part (6) for mounting the body part (5) to the chain. The acceleration sensor (22) is configured to detect acceleration in the direction of gravity when the body (5) attached to the chain is lifted upward and then dropped within the range of the slack amount of the chain.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a chain measuring device, a chain measuring system, and a method for calculating chain slack. [Background technology]

[0002] In the case of a chain such as a drive chain, the chain elongation is measured to determine the chain's lifespan. Also, the amount of slack in the chain is measured to ensure that the chain is tensioned within an appropriate range. These measurements of chain elongation and slack are usually performed by an operator using a vernier caliper or a dedicated tool (see Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 61-42401 Summary of the Invention [Problem to be solved by the invention]

[0004] However, when measuring a chain with the above-mentioned vernier calipers, there is variation in measurement accuracy between workers. Also, when using a dedicated tool such as that shown in Patent Document 1, although the accuracy is improved compared to using vernier calipers, the worker still has to measure the chain visually, and there is room for further improvement in terms of measurement accuracy and operability.

[0005] SUMMARY OF THE PRESENT EMBODIMENTS An object of the present invention is to provide a chain measuring device, a chain measuring system, and a method for calculating the amount of slack in a chain, which are capable of measuring a chain simply and with high accuracy. [Means for solving the problem]

[0006] One aspect of the present invention is a chain measuring device for measuring the amount of slack in a chain wound around a sprocket, comprising a main body equipped with an acceleration sensor capable of detecting acceleration in the direction of gravity, and a mounting portion for attaching the main body to the chain, wherein the acceleration sensor is configured to detect the acceleration in the direction of gravity when the main body attached to the chain is lifted upward within the range of the chain slack and then dropped. Effect of the Invention

[0007] According to the present invention, chain measurements can be performed simply and with high accuracy. [Brief description of the drawings]

[0008] [Figure 1] 1 is a schematic diagram showing a chain measurement system according to an embodiment of the present invention; [Diagram 2] 1 is an exploded view of a chain measuring device according to an embodiment of the present invention. [Diagram 3] 1A is a plan view of the chain measuring device attached to a chain, (b) is a side view of the chain measuring device attached to a chain, and (c) is a cross-sectional view of a probe pin. [Figure 4] FIG. 2 is a schematic diagram showing a position sensor. [Diagram 5] FIG. 2 is a block diagram of a terminal device. [Figure 6] FIG. 11 is a flowchart showing a process for determining a life span of a chain. [Figure 7] FIG. 11 is a flowchart showing a chain slack determination process. [Figure 8] Schematic diagrams showing the operation when determining chain slack, where (a) is a diagram showing the state before the chain measuring device is installed, (b) is a diagram showing the state after the chain measuring device is installed, (c) is a diagram showing the state after the chain measuring device has been lifted upward, and (d) is a diagram showing the state after the chain measuring device has been dropped. [Figure 9]FIG. 13 is a diagram showing a modified example of the chain measuring device. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] <Outline of chain measurement system configuration> A chain measuring system 1 according to an embodiment of the present invention will be described below with reference to Figures 1 to 9. As shown in Figure 1, the chain measuring system 1 includes a chain measuring device 2 attached to a chain 4, and a terminal device 3 such as a smartphone. The chain measuring device 2 and the terminal device 3 are configured to be capable of wireless communication, and are configured so that the terminal device 3 determines the lifespan of the chain 4 and the amount of slack (looseness) of the chain 4 based on data measured by the chain measuring device 2. <Structure of chain measuring device>

[0010] 2, the chain measuring device 2 includes a main body 5 and an attachment portion 6 for attaching the main body 5 to the chain 4. The main body 5 includes a cylindrical housing 7, with a slide shaft 9 and a fixed shaft 10 protruding from both ends thereof. More specifically, the housing 7 includes a main body 7a and left and right end caps 7b, 7c, and the slide shaft 9 and fixed shaft 10 protrude from the end caps 7b, 7c, respectively.

[0011] Of the slide shaft 9 and fixed shaft 10, the fixed shaft 10 is fixed to the end cap 7c by a bolt 13. The slide shaft 9 is slidably supported by the end cap 7b and a stopper 17. The stopper 17 is a fixed member fixed to the main body 7a by a screw 18. A stopper nut 16 is attached to the slide shaft 9, and a coil spring 15 is provided between the stopper nut 16 and the stopper 17 as a biasing member. The slide shaft 9 is biased outward by the coil spring 15.

[0012] Furthermore, probe pins 11, 12 constituting the above-mentioned mounting portion 6 are attached to the slide shaft 9 and fixed shaft 10 in a direction intersecting the axis of the shaft. These probe pins 11, 12 are configured to be inserted between the rollers of the chain 4. Then, each of the probe pins 11, 12 is inserted between the rollers of the chain 4 and pressed against the outer diameter of the roller by the biasing force of the coil spring 15, whereby the chain measuring device 2 is attached to the chain 4.

[0013] Further, a bracket 20 is integrally formed with the stopper 17. The internal configuration within the housing 7 is sub-assembled with the stopper 17 and the bracket 20 at the center, and a position sensor 19 is attached to this bracket 20. Furthermore, a board 21 is attached to the bracket 20, and this board 21 is provided with an acceleration sensor 22 and a communication module 23 for wireless communication with the terminal device 3. In this embodiment, a resistive position sensor is mounted as the position sensor 19, a MEMS acceleration sensor is mounted as the acceleration sensor 22, and a Bluetooth (registered trademark) communication module is mounted as the communication module 23.

[0014] In addition, a power supply bracket 26 is attached integrally to the bracket 20 by a knock pin 25, and a battery holder 27 for mounting a battery (not shown) is attached to the power supply bracket 26.

[0015] Brackets 29, 30 for a power button are fixed to the main body 7a of the housing 7 with screws 31, 32, and a switch board 33 is attached to the brackets 29, 30. A power switch 35 made of a tactile switch is provided on the switch board 33, and the chain measuring device 2 is turned on / off when the user presses this power switch 35.

[0016] <Details of the mounting area> Next, a detailed configuration of the area surrounding the attachment portion where the chain measuring device 2 is attached to the chain 4 will be described. First, the guide function of the housing 7 will be described. As shown in Fig. 1, the chain 4 wound around a drive sprocket 51 and a driven sprocket 52 has a tight side 42 with high tension on the upper side and a slack side 41 with low tension on the lower side. Unlike the tight side 42, the slack side 41 is not covered by a chain case or the like, making it easy for the user to access, but it is curved downwards (a so-called catenary curve).

[0017] For this reason, if an acceleration sensor is simply attached to the slack side 41 of the chain 4, the curve of the chain 4 may cause the acceleration sensor to tilt, which may affect the measurement accuracy. Furthermore, even when measuring the elongation of the chain 4, if the chain is curved, it is difficult to accurately measure the length of the chain. For this reason, in this embodiment, as shown in Figures 3(a) and (b), tension is applied to the chain 4 between the probe pins 11 and 12 by the coil spring 15. As a result, even on the slack side 41 of the chain 4, a predetermined tension is applied between the probe pins 11 and 12 by the biasing force of the coil spring 15, so that the chain 4 can be stretched, and catenary (curvature) of the chain 4 can be suppressed.

[0018] Furthermore, when attaching the chain measuring device 2, the probe pins 11, 12 are inserted between the rollers of the chain 4 until the top surface 71 of the housing 7 abuts against the outer periphery of the chain 4, so that the top surface 71 of the housing 7 serves as a guide surface, allowing the posture of the main body 5 to be aligned with the chain 4 between the above-mentioned probe pins 11, 12. This makes it possible to suppress tilting of the main body 5 incorporating the acceleration sensor 22.

[0019] Next, we will explain the shapes of the tips 11t, 12t of the probe pins 11, 12. Note that the shapes of the tips 11t, 12t of the probe pins 11, 12 are substantially the same for the probe pin 11 and the probe pin 12, so in the following explanation, only the shape of the tip 12t of the probe pin 12 will be explained.

[0020] As shown in Figures 2 and 3, the probe pin 12 has a circular cross-sectional shape at its base 12b, which is press-fitted into a hole formed at the end of the fixed shaft 10, while its tip 12t, which is inserted between the rollers of the chain 4, has an irregular cross-sectional shape.

[0021] More specifically, as shown in Fig. 3(c), the tip 12t of the probe pin 12 is cut out so that side surfaces 12t1 and 12t2 facing the link plates of the chain 4 are flat when the tip 12t is inserted between the rollers of the chain 4. In addition, the surfaces 12t3 and 12t4 coming into contact with the rollers of the chain 4 are curved. As a result, the cross-sectional shape of the tip 12t is formed so that the length L1 in a first direction corresponding to the width direction of the chain 4 when inserted between the rollers of the chain 4 is shorter than the length L2 in a second direction corresponding to the running direction of the chain 4.

[0022] Therefore, the chain measuring device 2 can be attached to a wide range of chains, from bicycle chains with narrow spacing between the link plates to motorcycle chains with wider spacing between the link plates than bicycle chains. Also, by making the length L2 in the second direction to which the tension of the coil spring 15 is applied longer than the length L1 in the first direction, the rigidity of the probe pin 12 is ensured and deflection of the probe pin 12 is suppressed. In addition, since the surface 12t4 that contacts the roller of the chain 4 is formed by a curved surface, the roller of the chain 4 and the probe pin 12 come into point contact, improving the measurement accuracy.

[0023] <Details of the chain elongation measurement mechanism> Next, a chain elongation measuring mechanism using the above-mentioned position sensor 19 will be described with reference to Figures 2 and 4. As shown in Figure 4, the position sensor 19 is configured so that a sensor lever 191 is inserted into the mounting groove 91 of the slide shaft 9, and this sensor lever 191 moves together with the slide shaft 9 to detect the position of the probe pin 11.

[0024] As described above, the position sensor 19 and the slide shaft 9 form a sub-assembly via the bracket 20 (see FIG. 2). When this sub-assembly is assembled into the housing 7, the stopper nut 16 attached to the slide shaft 9 is pressed against the end cap 7b, causing the coil spring 15 to be compressed from its natural length. On the other hand, before assembly into the housing 7, the position of the stopper nut 16 is not restricted by the end cap 7b. If, in the natural state of the coil spring 15, the position of the mounting groove 91 of the slide shaft 9 is located axially outward of the movement range of the sensor lever 191, when the sensor lever 191 is engaged with the mounting groove 91 of the slide shaft 9 during assembly of the sub-assembly, a reaction force from the coil spring 15 is applied to the sensor lever 191 before the sub-assembly is assembled into the housing 7.

[0025] For this reason, in this embodiment, the position sensor 19 is attached to the bracket 20 so that the position of the mounting groove 91 of the slide shaft 9 when the coil spring 15 is at its natural length is within the movable range of the sensor lever 191 or in the vicinity of the movable range of the sensor lever 191 (for example, the distance between the mounting groove 91 and the end of the movable range of the sensor lever 191 on the mounting groove 91 side is within 2 mm).

[0026] As a result, when assembling the sub-assembly, it is not necessary to fit the sensor lever 191 of the position sensor 19 into the mounting groove 91 of the slide shaft 9 with the slide shaft 9 pressed in with a finger, or the amount of pressing of the slide shaft 9 is reduced, improving the ease of assembly of the sub-assembly. Also, when the sub-assembly is assembled, the load applied to the sensor lever 191 can be reduced.

[0027] <Terminal device configuration> Next, the configuration of the terminal device 3 will be described. As shown in Fig. 5, the terminal device 3 of this embodiment is a portable computer such as a smartphone, and includes a CPU 301 as a calculation unit, and a ROM 302 and a RAM 303 that constitute a storage unit. The terminal device 3 also includes a communication module 305 that can communicate with the chain measuring device 2, a display 309, and a network interface 310. The CPU 301, ROM 302, RAM 303, communication module 305, display 309, and network interface 310 are connected to each other via a bus 307 so as to be able to communicate with each other.

[0028] The ROM 302 stores a lifespan determination program 321 for determining the lifespan of the chain 4 and a slack determination program 322 for determining the slackness of the chain 4 based on the measurement results of the chain measuring device 2 described above. The lifespan determination program 321 and the slack determination program 322 are executed by the CPU 301 to perform a lifespan determination process and a slack determination process for the chain 4. In this embodiment, the lifespan determination program 321 and the slack determination program 322 constitute a chain measurement application executed in the terminal device 3. The terminal device 3 is capable of downloading such a chain measurement application from the server device 400 via the network interface 310 and the Internet 320. The network interface 310 can be configured using a communication standard for wired communication such as IEEE 802.3, or wireless communication such as IEEE 802.11 and 802.15. The server device 400 is configured by a computer equipped with a storage device and a calculation unit that store the lifespan determination program 321 and the slack determination program 322.

[0029] <Lifespan Judgment Process> Next, the chain lifespan determination process will be described with reference to Figures 5 and 6. When the above-mentioned lifespan determination program 321 is executed, the CPU 301 functions as a lifespan determination unit 311 that determines the lifespan from the elongation of the chain 4, and executes the lifespan determination process. Specifically, as shown in Figure 6, when executing the chain lifespan determination process, the user first turns on the power switch 35 of the chain measuring device 2 and starts up a chain measurement app including the lifespan determination program 321 in the terminal device 3 (step S1 in Figure 6).

[0030] Next, when the chain measurement app on the chain measurement device 2 and the terminal device 3 is launched, the chain measurement device 2 and the terminal device 3 are paired (S2). Once the chain measurement device 2 and the terminal device 3 are paired, the user pushes the slide shaft 9 of the chain measurement device 2 into the housing 7. Once the slide shaft 9 is pushed in, the terminal device 3 obtains an initial value from the chain measurement device 2, and it is confirmed whether communication between the terminal device 3 and the chain measurement device 2 is normal (S3).

[0031] Once it is confirmed that communication is normal, the user operates the terminal device 3 to select the type of chain to be measured. In this embodiment, an appropriate chain size and seal type are selected from a plurality of selectable chain sizes and seal types (S4). Once the size and seal type of the chain 4 have been selected, the terminal device 3 is operated with the slide shaft 9 of the chain measuring device 2 in a released state (a state in which the slide shaft 9 is not pressed in) to perform calibration (S5). By performing calibration, the initial position of the probe pin 11 in the released state (hereinafter referred to as the calibration value) is calibrated, and the result is communicated to the terminal device 3.

[0032] When the calibration is completed, the LED 40 (see FIG. 3) serving as a display device of the chain measuring device 2 lights up red, and the user attaches the chain measuring device 2 to the chain 4 in this state (S6). Specifically, the user pushes in the slide shaft 9 so that the number of links between the probe pins 11, 12 is a specified number of links, and then attaches the chain measuring device 2 to the chain 4. Note that in this embodiment, the completion of the calibration is notified by the lighting of the LED 40, but the completion of the calibration may also be notified by, for example, displaying a message on the display of the terminal device 3. Also, the lighting of the LED 40 may be configured to notify that the power of the chain measuring device 2 has been turned on.

[0033] Then, when the chain measuring device 2 is attached to the chain 4, the user operates the terminal device 3 (for example, tapping the display 309) to start measurement (S7). When measurement of the position of the probe pin 11 (hereinafter referred to as the actual measurement value) is completed (S8), the chain measuring device 2 communicates the measured data to the terminal device 3.

[0034] When the terminal device 3 receives the measurement results from the chain measuring device 2, it obtains a zero correction value from the chain size and type information selected in step S4, calculates the difference between the actual measurement value and the calibration value corrected by the zero correction value, and regards this difference as the elongation (displacement) of the chain 4 (S9).

[0035] The above-mentioned zero correction value is a value that represents the difference between the designed position of the probe pin 11 in the absence of chain elongation and the initial position at which calibration was performed, and differs for each type of chain. Therefore, by correcting the calibration value with the zero correction value, it is possible to determine the designed position of the probe pin 11 in the absence of chain elongation, and the amount of elongation of the chain 4 can be determined by determining the difference between the actual measurement value and the calibration value corrected by the zero correction value.

[0036] Once the amount of elongation of the chain 4 has been determined, the terminal device 3 calculates the elongation rate, which is the ratio of the amount of elongation to the reference length of the selected chain 4, and judges the lifespan of the chain based on this elongation rate value. The determined result of the chain lifespan is then displayed on the display 309 of the terminal device 3, and the terminal device 3 communicates the judgment result to the chain measuring device 2 (S10). In this embodiment, the display 309 shows the elongation rate of the chain, as well as a three-level chain lifespan diagnosis result: "The chain is in good condition," "It is nearing the time to replace the chain," or "It is recommended to replace the chain."

[0037] Furthermore, upon receiving the judgment result, the chain measuring device 2 lights up the LED 40 to notify the user. The threshold value of the chain elongation rate for judging the chain lifespan described above is set to a different value depending on the type of chain. The chain lifespan diagnosis result may be shown on the display 309 using colors other than characters, and the chain lifespan may be shown on the display 309 as a percentage, for example.

[0038] <Sag Judgment Processing> Next, the chain slack determination process will be explained with reference to Figures 5, 7 and 8. When the above-mentioned slack determination program 322 is executed, the CPU 301 functions as a slack determination unit 312 that determines whether or not the slack of the chain 4 is within an appropriate range, and executes the slack determination process. Specifically, as shown in Figure 7, when executing the chain slack determination process, the user turns on the power switch 35 of the chain measuring device 2 and starts up a chain measurement application including the slack determination program 322 in the terminal device 3 (step S20 in Figure 7).

[0039] Then, when the chain measurement apps on the chain measurement device 2 and terminal device 3 are launched, the chain measurement device 2 and terminal device 3 are paired (S21). Once the chain measurement device 2 and terminal device 3 are paired, the user attaches the chain measurement device 2 to the chain 4 (S22, (a) to (b) in FIG. 8).

[0040] Once the chain measuring device 2 is attached to the chain 4, the user lifts the chain measuring device 2 to the top dead center (S23), as shown in Fig. 8(c). Once the chain measuring device 2 has been lifted to the top dead center, the accelerations in the X, Y and Z axes directions at this top dead center are communicated as initial values ​​from the chain measuring device 2 to the terminal device 3 (S24). This initial value is used for horizontal correction of the acceleration in the Z axis direction.

[0041] Once the initial acceleration value has been acquired, the user operates the terminal device 3 (e.g., taps on the display 309) to start measurement, and at the same time, releases the chain measuring device 2 to drop it (S25, see FIG. 8(d)). When measurement is started in step S25, the acceleration sensor 22 of the chain measuring device 2 measures the acceleration in the Z-axis direction (gravity direction) for a predetermined time (e.g., up to 0.5 sec in this embodiment), and transmits the measured acceleration to the terminal device 3 (S26).

[0042] The measured acceleration values ​​transmitted from the chain measuring device 2 are stored as time-series acceleration data in the memories 302, 303 of the terminal device 3, and the CPU 301 of the terminal device 3 detects the maximum acceleration value in this time-series data (S28).

[0043] When the maximum value of the acceleration is detected, it is assumed that the chain measuring device 2 has reached the bottom dead center at the time when the acceleration reaches its maximum value (the state in Figure 8(d)), and the CPU 301 of the terminal device 3 performs a double-order numerical integration of the Z-direction acceleration from the starting value to the maximum value (S29), and this double-order numerically integrated Z-direction acceleration value is used as an estimated value of the slack amount (slack displacement) of the chain 4 (S30).

[0044] Then, the CPU 301 of the terminal device 3 judges whether the calculated amount of slack of the chain 4 is within the appropriate slack range stored in the storage units 302 and 303, and displays the judgment result on the display 309. For example, in this embodiment, if the calculated amount of slack is within the appropriate range, "It is within the appropriate range." If the calculated amount of slack is outside the appropriate range on the side with less slack, "The chain is too tight, please loosen it" is displayed on the display 309 along with the judgment result, and an instruction for additional adjustment is displayed on the display 309. If the calculated amount of slack is outside the appropriate range on the side with more slack, "The chain is too slack, please tighten it" is displayed on the display 309 along with the judgment result. The terminal device 3 also communicates the judgment result to the chain measuring device 2, and notifies the user of the result using the LED 40 of the chain measuring device 2 (S31).

[0045] <Summary>

[0046] As described above, the chain measuring device (2) according to the present embodiment is a chain measuring device (2) for measuring the amount of slack in the chain (4) wound around the sprockets (51, 52), A main body (5) having an acceleration sensor (22) capable of detecting acceleration in the direction of gravity; and a mounting portion (6) for mounting the main body portion (5) to the chain (4), The acceleration sensor (22) is configured to detect the acceleration in the direction of gravity when the main body (5) attached to the chain (4) is lifted upward within the range of the slack in the chain (4) and then dropped.

[0047] In this way, by attaching the chain measuring device 2 with the built-in acceleration sensor 22 to the chain 4 and lifting and dropping the chain measuring device 2 upward within the range of slack in the chain 4, it is possible to obtain the acceleration response value when the chain measuring device 2 is dropped within the above-mentioned slack range. Then, by performing second-order numerical integration on this acceleration time series data, it is possible to calculate the amount of slack in the chain 4. With this method, the amount of slack in the chain 4 can be measured simply by lifting and dropping the chain measuring device 2, which simplifies the measurement of the amount of slack in the chain 4 and also reduces errors between operators performing the measurement.

[0048] The attachment portion (6) is configured to attach the main body portion (5) to the endless chain (4), The main body (5) includes a housing (7) that extends in the running direction of the chain (4) when attached to the chain (4), The housing (7) has a guide surface that comes into contact with the chain (4) when the main body (5) is attached to the chain (4) by the attachment portion (6).

[0049] In this way, by making the housing 7 a guide surface that contacts the chain, when attaching the chain measuring device 2 to the chain 4, it is possible to attach the main body 5 containing the acceleration sensor 22 to the chain 4 with as little tilt as possible, thereby improving the measurement accuracy by the acceleration sensor 22.

[0050] The main body portion (5) is a first shaft (9) that protrudes from a first end in the extension direction of the housing (7) and is supported slidably; a second shaft (10) protruding from a second end of the housing (7) opposite to the first end in the extension direction; a biasing member (15) that biases the first shaft (9) in a direction protruding from the housing (7), The mounting portion (6) is a first member (11) extending from the first shaft (9) in a direction intersecting an axial direction of the first shaft (9); a second member (12) extending from the second shaft (10) in a direction intersecting the axial direction of the second shaft (10), The first and second members (11, 12) are inserted between rollers of the chain (4) at different positions in the traveling direction, whereby the main body portion (5) is attached to the chain (4).

[0051] Therefore, even if the chain measuring device 2 is attached to the slack side of the chain 4, the biasing member 15 can apply an appropriate tension between the first and second members 11, 12. Furthermore, this, combined with the fact that the top surface 71 of the housing 7 is a guide surface, can prevent the main body 5 from tilting during attachment.

[0052] In this embodiment, the biasing member 15 is formed using a coil spring, but any type of elastic member may be used as long as it can apply an appropriate tension to the chain 4, and the first and second members 11 and 12 do not necessarily have to be formed by probe pins. In this embodiment, the upper surface 71 is the guide surface, but the lower surface 72 (see FIG. 3(b)) may be the guide surface. In this case, the probe pins 11 and 12 are attached to the shafts 9 and 10 so as to extend in the direction of gravity (downward), and the main body 5 is attached to the chain from the upper side (inner circumference side). Furthermore, the shafts 9 and 10, the biasing member 15, the first member 11, and the second member 12 may be omitted, and a fastening member such as a magic band may be provided on the housing 7 as the attachment portion (6) to fix the housing 7 to the chain.

[0053] The main body (5) is provided with a detection sensor (19) for detecting the amount of elongation of the chain (4) based on the distance between the first member (11) and the second member (12).

[0054] In this way, by providing the detection sensor 19, it becomes possible to easily and accurately measure not only the amount of slack in the chain 4 but also the elongation of the chain 4 using the chain measuring device 2. In particular, it becomes possible to measure the elongation of the chain 4 in a state in which tension is applied to the chain 4 by the biasing member 15 and the catenary of the chain 4 is also suppressed by the guide surface 71 of the housing 7, so that the elongation of the chain can be measured with high accuracy. Note that in this embodiment, the detection sensor is configured by the position sensor 19 that detects the position of the probe pin 11 as the first member, but it may also be configured by, for example, a sensor that detects the distance between the probe pins 11, 12, etc.

[0055] The first member (11) and the second member (12) each have a tip portion (11t, 12t) to be inserted between rollers of the chain (4), The tip portions (11t, 12t) of the first member (11) and the second member (12) are When a direction corresponding to the width direction of the chain (4) when the tip portions (11t, 12t) are inserted between the rollers of the chain is defined as a first direction, and a direction corresponding to the running direction of the chain (4) when the tip portions (11t, 12t) are inserted between the rollers of the chain (4) is defined as a second direction, In the cross-sectional shape, the length (L1) in the first direction is shorter than the length (L2) in the second direction.

[0056] In this way, by configuring the width in the first direction of the tip portions (11t, 12t) of the first member (11) and the second member (12) to be narrow, the chain measuring device 2 can be attached even to a chain with a narrow chain width, such as a bicycle chain.

[0057] In this embodiment, the chain measurement system (1) is configured by the chain measurement device (2) and a computer (3) configured separately from the chain measurement device (2), The chain measuring device (2) includes a communication module (23) capable of communicating with the computer (3), The terminal device (3) a storage unit (302, 303) for storing time series data of the acceleration in the direction of gravity detected by the acceleration sensor (22) when the main body (5) is lifted upward within the range of the slack of the chain (4) and then dropped; The apparatus further includes a calculation unit (301) for calculating the amount of slack in the chain (4) based on the time-series data of the acceleration stored in the memory units (302, 303).

[0058] In this way, the chain measuring device 2 can be manufactured at low cost by separately configuring the chain measuring device 2, which measures acceleration, and the computer 3, which calculates the amount of chain slack based on the time series data of acceleration measured by the chain measuring device 2. Also, the terminal device 3 can store log data 323, such as previously measured amounts of slack, in a memory unit, making it easy to check changes in the condition of the chain.

[0059] In addition, the calculation unit 301 of the computer 3 can also calculate the elongation of the chain based on the detection result of the detection sensor 19, so that the slack and elongation of the chain 4 can be measured and managed in an integrated manner by a single terminal device 3. The computer 3 may be configured as a smartphone, a desktop terminal, or the like. In addition to the above-mentioned smartphone, the computer may be configured as a server device 400 that can communicate with the terminal device 3. For example, the server device 400 may acquire measurement data (time series data of acceleration and data related to the elongation of the chain 4) of the chain measuring device 2 via the terminal device 3. The server device 400 may then calculate the amount of slack and data related to the amount of elongation of the chain based on the life determination program 321 and the slack determination program 322 stored in the storage unit by the calculation unit. In this case, the results calculated by the server device 400 are communicated to the terminal device 3 and displayed to the user. The chain measuring device 2 may indirectly communicate with the server device 400 via the terminal device 3, or may access an internetwork to directly communicate with the server device 400. In this manner, in this embodiment, regardless of whether the communication is indirect or direct, the chain measuring device 2 is said to be capable of communicating with the computer 400 via a communication module. Furthermore, various log information may also be stored in the server device 400.

[0060] In the method for calculating the amount of slack in the chain (4) according to this embodiment, the computer (3) executes the following processes. a) Obtaining time series data of the acceleration in the direction of gravity detected by an acceleration sensor (22) attached to the chain (4) when the chain (4) is lifted upward within the range of the slack in the chain (4) and then dropped. b) A second-order numerical integration is performed for a predetermined range of the acquired time series data of the acceleration in the gravity direction to calculate the amount of slack in the chain (4).

[0061] In this way, the amount of slack in the chain 4 can be calculated by performing second-order numerical integration on the time series data of the acceleration in the gravity direction.

[0062] A computer program (322) for causing a computer to execute the method for calculating the amount of slack in the chain (4).

[0063] In this way, by configuring the method for calculating the amount of slack in the chain (4) as a computer program 322, the method for calculating the amount of slack can be implemented, for example, in the form of a smartphone app. In this embodiment, the program 322 is stored in ROM 302, which is an example of a computer-readable recording medium.

[0064] Furthermore, in the above-described embodiment, the chain measuring device 2 and the terminal device 3 are provided separately, but, for example, the calculation unit 301 and the memories 302, 303 of the terminal device 3 may be provided on the chain measuring device 2 side. In this case, it is desirable that the chain measuring device 2 is provided with a display 100 as shown in FIG. 9 as a display device for displaying the calculated amount of slack and the elongation of the chain. Note that the chain measuring device 2 may naturally be provided with the display 100 even when the amount of slack and the elongation of the chain 4 are calculated using the terminal device 3. Furthermore, the inventions described in the above-described embodiment may be combined in any manner. [Explanation of symbols]

[0065] 2: Chain measuring device 4: Chain 5: Main body 6: Mounting part 22: Acceleration sensor 51,52: Sprocket

Claims

1. A chain measuring device for measuring the amount of slack in a chain wound around a sprocket, comprising: A main body portion including an acceleration sensor capable of detecting acceleration in the direction of gravity; an attachment portion for attaching the main body portion to the chain, The acceleration sensor is configured to detect the acceleration in the direction of gravity when the main body attached to the chain is lifted upward within the range of the slack of the chain and then dropped. A chain measuring device comprising:

2. The attachment portion is configured to attach the main body portion to the endless chain, The main body includes a housing that extends in a running direction of the chain when attached to the chain, The housing has a guide surface that comes into contact with the chain when the main body is attached to the chain by the attachment portion.

2. The chain measuring device according to claim 1.

3. The main body portion is a first shaft protruding from a first end in an extension direction of the housing and supported slidably; a second shaft protruding from a second end of the housing opposite to the first end in the extension direction; a biasing member that biases the first shaft in a direction protruding from the housing, The mounting portion is a first member extending from the first shaft in a direction intersecting an axial direction of the first shaft; a second member extending from the second shaft in a direction intersecting an axial direction of the second shaft, The first and second members are inserted between rollers of the chain at different positions in the running direction, thereby attaching the main body to the chain.

3. The chain measuring device according to claim 2.

4. The main body includes a detection sensor for detecting an amount of elongation of the chain based on a distance between the first member and the second member.

4. The chain measuring device according to claim 3.

5. the first member and the second member each have a tip portion that is inserted between rollers of the chain, The tip portions of the first member and the second member each have When the direction corresponding to the width direction of the chain when the tip portion is inserted between the rollers of the chain is defined as a first direction, and when the direction corresponding to the running direction of the chain when the tip portion is inserted between the rollers of the chain is defined as a second direction, In the cross-sectional shape, the length in the first direction is shorter than the length in the second direction.

5. The chain measuring device according to claim 3 or 4.

6. a storage unit that stores time series data of the acceleration in the direction of gravity detected by the acceleration sensor when the main body attached to the chain is lifted upward within a range of the slack of the chain and then dropped; a calculation unit that calculates a slack amount of the chain based on the time series data of the acceleration stored in the memory unit, 6. A chain measuring device according to claim 1, wherein the chain measuring device is a first measuring device.

7. A chain measuring device according to claim 1; A computer, The chain measuring device includes a communication module capable of communicating with the computer, The computer includes: a storage unit that stores time series data of the acceleration in the direction of gravity detected by the acceleration sensor when the main body is lifted upward within the range of the slack in the chain and then dropped; a calculation unit that calculates a slack amount of the chain based on the time series data of the acceleration stored in the memory unit, A chain measurement system comprising:

8. The attachment portion is configured to attach the main body portion to the endless chain, The main body portion is a housing having a guide surface that extends in a running direction of the chain when attached to the chain and that comes into contact with the chain when the main body is attached to the chain by the attachment portion; a first shaft protruding from a first end in an extension direction of the housing and supported slidably; a second shaft protruding from a second end of the housing opposite to the first end in the extension direction; a biasing member that biases the first shaft in a direction protruding from the housing, The mounting portion is a first member extending from the first shaft in a direction intersecting an axial direction of the first shaft; a second member extending from the second shaft in a direction intersecting an axial direction of the second shaft, The first and second members are inserted between rollers of the chain at different positions in the running direction, thereby attaching the main body to the chain.

8. The chain measurement system of claim 7.

9. the main body portion includes a detection sensor capable of detecting a change in a distance between the first member and the second member, The calculation unit calculates an amount of elongation of the chain based on a detection result of the detection sensor.

9. The chain measurement system of claim 8.

10. A method for calculating a slack amount of a chain, comprising the steps of: a) acquiring time series data of acceleration in the direction of gravity detected by an acceleration sensor attached to the chain when the chain is lifted upward within the range of the slack of the chain and then dropped; b) performing second-order numerical integration for a predetermined range of the acquired time series data of the acceleration in the gravity direction to calculate the amount of slack in the chain; A method for calculating the amount of slack in a chain.

11. A computer program for causing a computer to execute the method for calculating the amount of slack in a chain according to claim 10.

12. A computer-readable recording medium having the computer program according to claim 11 recorded thereon.

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