Length detection sensor and telescopic suspension arm

Abstract

The utility model relates to the field of engineering machinery, and discloses a length detection sensor and a telescopic suspension arm, the length detection sensor comprises a line concentration wheel assembly and a wire guide wheel assembly, and the line concentration wheel assembly comprises a line concentration wheel used for collecting and winding a measured long line; the wire guide wheel assembly comprises a rotation amount conversion part, a wire guide wheel and a pressing wheel, the wire guide wheel and the pressing wheel are arranged adjacently in a pressing roller shape, the wire guide wheel can rotate freely, and the rotation amount conversion part is used for measuring the circumferential angle change value of the wire guide wheel; wherein the free end of the length measuring line penetrates through the space between the line guiding wheel and the pressing wheel to extend outwards, the pressing wheel is used for pressing the length measuring line on the outer side rim of the line guiding wheel, and the movement of the length measuring line can drive the line guiding wheel to rotate. According to the length detection sensor and the telescopic suspension arm, the measurement error of the moving length of the length measurement line can be effectively reduced, and the precision of detecting the telescopic length of the suspension arm is improved.

Description

Technical Field

[0001] The present application belongs to the field of engineering machinery, and specifically relates to a length detection sensor and a telescopic boom. Background Art

[0002] For engineering lifting equipment, the telescopic length of the boom is an important parameter for confirming the lifting capacity. When there is an error in the parameter, it will affect the lifting performance of the crane and even cause a safety accident. Therefore, exploring how to accurately detect the telescopic length data of the boom is of great significance to ensure the safety of the operation. At present, a draw-wire sensor is often used in this field to detect the telescopic length of the boom. Specifically, the extension length of the measuring cable is calculated by counting the number of rotations and angles of the draw-wire sensor, thereby indirectly measuring the telescopic length of the boom. However, the measuring cable in the draw-wire sensor usually has to be wound in multiple layers in the collection wheel. Due to the different distances between each layer and the main shaft axis, the rotational motion of the collection wheel and the linear motion of the measuring cable are not linearly related, which leads to measurement errors and affects the accuracy of the data. Summary of the invention

[0003] In response to at least one of the above-mentioned defects or shortcomings of the prior art, the present application provides a length detection sensor and a telescopic boom, which can effectively reduce the measurement error of the moving length of the measuring line, thereby improving the accuracy of detecting the telescopic length of the boom.

[0004] In order to achieve the above-mentioned object, the present application provides a length detection sensor on one hand, and the length detection sensor comprises:

[0005] The line collection wheel assembly includes a line collection wheel for collecting and winding long test lines;

[0006] The wire wheel assembly comprises a rotation amount conversion component and a wire wheel and a pressure wheel which are arranged adjacent to each other in the shape of a pressure roller, wherein the wire wheel can rotate freely, and the rotation amount conversion component is used to measure the circumferential angle change value of the wire wheel;

[0007] The free end of the length measuring line extends outward through between the wire wheel and the clamping wheel, and the clamping wheel is used to press the length measuring line against the outer wheel rim of the wire wheel, so that the movement of the length measuring line can drive the wire wheel to rotate.

[0008] In some embodiments, the wire collecting wheel rotates around the main axis, the wire wheel is mounted on the wire wheel shaft, the wire wheel shaft is arranged parallel to the main axis and spaced apart, and the length measuring line can drive the wire wheel and the wire wheel shaft to rotate synchronously.

[0009] In some embodiments, bearings are respectively installed at both ends of the wire wheel shaft.

[0010] In some embodiments, an axial long groove is formed on the guide wheel shaft, a convex key is formed on the inner rim of the guide wheel, and the guide wheel moves along the axial long groove in a sliding manner through the convex key.

[0011] In some embodiments, the wire wheel shaft is installed on a mounting frame in parallel and at intervals with the main shaft, a connecting rod is hinged on the mounting frame, the pressure wheel is hinged to the free end of the connecting rod, a compression spring is connected between the connecting rod and the mounting frame, and the compression spring is used to push the pressure wheel to press against the outer wheel rim of the wire wheel.

[0012] In some embodiments, the preload force of the compression spring is set to keep the angular velocity of the close contact section between the length measuring wire and the guide wheel consistent.

[0013] In some embodiments, a circumferential limiting groove for limiting the length measuring wire is formed on the outer rim of the guide wheel.

[0014] In some embodiments, the hub reel assembly includes a coil spring plate disposed within the hub reel.

[0015] In some embodiments, the rotation amount conversion component is at least one of a potentiometer and an encoder;

[0016] Alternatively, the rotation amount conversion component includes a magnet and a Hall sensor element, the magnet is mounted on the end of the wire wheel shaft, and the Hall sensor element is axially spaced apart at the end of the wire wheel shaft and spaced apart and aligned with the magnet.

[0017] A second aspect of the present application provides a telescopic boom, which includes the above-mentioned length detection sensor.

[0018] Through the above technical scheme, the length detection sensor of the present application can press the free end of the length measuring line on the line collection wheel onto the wire wheel, so that the length measuring line can drive the wire wheel to rotate synchronously when extending or retracting and ensure that there is no slippage between the two, so that the linear speed of the outer rim of the wire wheel is consistent with the moving speed of the length measuring line, and then the circumferential angle change value of the wire wheel is measured by the rotation amount conversion component and combined with its outer edge circumference data, so as to calculate the moving length of the length measuring line. In this way, the measured result is more direct and does not require correction. It can also avoid measurement errors caused by misalignment, jumping, accumulation, etc. of the length measuring line on the line collection wheel. Overall, the accuracy of calculating the moving length of the length measuring line is greatly improved, thereby realizing accurate feedback on the telescopic length of the boom and improving the safety of the boom operation.

[0019] Other features and advantages of the embodiments of the present application will be described in detail in the subsequent detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The accompanying drawings are used to provide a further understanding of the embodiments of the present application and constitute a part of the specification. Together with the following specific embodiments, they are used to explain the embodiments of the present application, but do not constitute a limitation on the embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without creative work. In the drawings:

[0021] Figure 1 It is a flowchart of a method for detecting the telescopic length of a boom in a specific implementation manner of the present application;

[0022] Figure 2 It is a cross-sectional schematic diagram of a length detection sensor in a specific embodiment of the present application, in which the rotation amount conversion component of the length detection sensor in the figure is a Hall sensor;

[0023] Figure 3 for Figure 2 A top view of a length detection sensor;

[0024] Figure 4 1 is a cross-sectional schematic diagram of another length detection sensor in a specific embodiment of the present application, in which the rotation amount conversion component of the length detection sensor is a potentiometer;

[0025] Figure 5 for Figure 2 Schematic diagram of the state when the measuring line of the length detection sensor is close to the wire wheel.

[0026] Description of Reference Numerals

[0027] 1 Mounting bracket 2 Cable collection wheel

[0028] 3 Wire reel 4 Length measuring line

[0029] 5 Spindle 6 Pressure wheel

[0030] 7 Wire reel shaft 8 Magnet

[0031] 9 Hall sensor element 10 Potentiometer DETAILED DESCRIPTION

[0032] The specific implementation of the present application is described in detail below in conjunction with the accompanying drawings. It should be understood that the specific implementation described here is only used to illustrate and explain the present application, and is not used to limit the present application.

[0033] The present application will be described in detail below with reference to the accompanying drawings and in conjunction with exemplary embodiments.

[0034] At present, the device commonly used in the field of engineering machinery to measure the telescopic length of the boom is a length sensor, which is mostly a pull-rope sensor. When the boom is telescopic, it can drive the length measuring cable to extend to different lengths, and at the same time drive the collection wheel to rotate. The telescopic length of the boom is indirectly calculated by measuring the angle and number of turns of the collection wheel. However, due to the limited width of the collection wheel, the length measuring cable in the collection wheel usually has to be wrapped around the collection wheel in multiple layers. Due to the different distances between each layer and the axis of the main shaft, the rotational movement of the main shaft and the linear movement of the length measuring cable are not linearly related. In order to compensate for the measurement errors caused by the existing technology, software interpolation compensation or writing of the measured conversion curve relationship is usually required to compensate for the loss of length measurement accuracy. For length sensors of different ranges, the number of winding layers and turns is different, and the required compensation data will also be different, and the workload of error compensation is large. Moreover, there will be slight differences in the length and winding method of the length measuring cable of the length sensor with the same range, which will also cause deviations in compensation correction, making it difficult to achieve accurate detection of the telescopic length of the boom.

[0035] In view of this, an exemplary embodiment of the present application provides a method for detecting the telescopic length of a boom, such as Figure 1 As shown, the method comprises the steps of:

[0036] S100: The fixed end of the length measuring wire 4 is wound and collected on the wire collecting wheel 2, and the free end of the length measuring wire 4 is extended outward through between the wire guide wheel 3 and the clamping wheel 6 which are arranged closely in a pressure roller shape and connected to the boom, so that the free end of the length measuring wire 4 moves with the boom extension and retraction and drives the wire guide wheel 3 to rotate synchronously;

[0037] S200: obtaining the circumferential angle change value of the wire wheel 3 within a length detection cycle;

[0038] S300: Calculate the moving length detection value of the length measuring wire 4 according to the circumferential angle change value of the wire wheel 3.

[0039] Specifically, in step S100, the free end of the length measuring wire 4 extends outward and is connected to the telescopic end of the boom, so that the boom can drive the length measuring wire 4 to extend synchronously, and at this time, the extension direction of the length measuring wire 4 is consistent with and parallel to the telescopic direction of the boom. Since the free end of the length measuring wire 4 passes through the adjacently arranged wire wheel 3 and the clamping wheel 6, the length measuring wire 4 is closely attached to the wire wheel 3 without sliding, so that during the movement of the free end of the length measuring wire 4, the linear movement of the length measuring wire 4 can be completely converted into the rotational movement of the wire wheel 3, realizing the synchronous rotation of the wire wheel 3.

[0040] In step S200, a length detection cycle can be a process in which the boom is extended or shortened from an initial length to a preset length. In this process, the boom drives the length measuring line 4 to move synchronously to a certain length, so that the guide wheel 3 rotates to a certain angle, so that the circumferential angle change value of the guide wheel 3 can be obtained, and the change value is the difference between the initial angle and the final angle of the guide wheel 3 within the cycle.

[0041] Therefore, when the boom is telescopically adjusted, the length measuring line 4 collected in the line collection wheel 2 can move synchronously with the boom, and the length measuring line 4 can drive the wire wheel 3 to rotate synchronously, so that the linear speed of the wire wheel 3 and the moving speed of the length measuring line 4 are consistent; after the boom stops telescoping, that is, after completing a length detection cycle, the wire wheel 3 also stops rotating, and the moving length detection value of the length measuring line can be calculated by obtaining the circumferential angle change value of the wire wheel 3, which can then be converted into the telescopic length of the boom, thereby completing the detection of the telescopic length of the boom. Thanks to the fact that the linear speed of the wire wheel 3 and the moving speed of the length measuring line 4 are always consistent, the error between the moving length detection value of the length measuring line 4 and the actual moving length is extremely small, thereby achieving accurate detection of the telescopic length of the boom.

[0042] It is understandable that in the next length detection cycle, the final value of the circumferential angle of the wire wheel 3 in the length detection cycle is subtracted from the final value of the circumferential angle of the previous length detection cycle to obtain the circumferential angle change value of the wire wheel 3 in the length detection cycle.

[0043] In this embodiment, the length measuring wire 4 is composed of an inner core and an outer sheath. Figure 5 When the free end of the measuring wire 4 extending outward is in close contact with the wire wheel 3, the close contact section of the measuring wire 4 extends in an arc shape along the outer wheel rim of the wire wheel 3. By obtaining the circumferential angle change value of the wire wheel 3, the circumferential displacement of the outer wheel rim of the wire wheel 3 can be calculated from the circumferential angle change value. However, the measuring wire 4 in close contact with the wire wheel 3 itself has a certain diameter. Therefore, when calculating the circumferential displacement of the close contact section of the measuring wire 4, the influence of the diameter of the measuring wire 4 on the circumferential displacement should be considered.

[0044] Preferably, the distance from the central axis of the close-fitting section of the measuring wire 4 to the center of the wire wheel 3 is used as the rotation radius of the close-fitting section, that is, the diameter of the measuring wire 4 is added to the diameter of the wire wheel 3, so as to calculate the circumferential displacement of the close-fitting section of the measuring wire 4, which can be converted into the moving length detection value of the measuring wire 4.

[0045] Therefore, when the wire wheel diameter of the wire wheel 3 is D1, the cable diameter of the length measuring wire 4 is D2, and the circumferential angle change value of the wire wheel 3 is θ, the moving length detection value L of the length measuring wire 4 satisfies Formula 1:

[0046]

[0047] The length measuring line 4 can be a cable, which can not only measure the length, but also be used as a transmission line to transmit power or communication signals when necessary. Of course, in other embodiments, the cable used to measure the length of the boom can also be a rope such as a steel wire rope or a hemp rope, and this application does not limit this.

[0048] When the wire wheel 3 rotates n times, the moving length detection value of the length measuring wire 4 can be regarded as the full circle moving value L1, and L1 satisfies Formula 2: L1 = (D1 + D2) * π * n; when the wire wheel 3 rotates less than one circle, the circumferential angle change value of the wire wheel 3 can be regarded as the zero residual angle γ, and the moving length detection value of the length measuring wire 4 can be regarded as the zero residual moving value L2, and L2 satisfies Formula 3:

[0049] To this end, within a length detection cycle, obtaining the circumferential angle change value of the wire wheel 3 may include obtaining the number of rotations n of the wire wheel 3. When the wire wheel 3 rotates less than one circle, the zero residual angle γ of the less than one circle may be obtained. When calculating the moving length detection value of the length measuring wire 4, the moving length detection value L may be calculated by calculating the full circle movement value L1 and the zero residual movement value L2 of the length measuring wire 4, wherein the moving length detection value L satisfies: L=L1+L2. Substituting into the above formula 2 and formula 3, it can be known that the moving length detection value L satisfies formula 4:

[0050] Therefore, when the wire wheel 3 rotates less than one circle, it is only necessary to obtain the zero-residue angle γ of the wire wheel 3 to calculate the moving length detection value L of the measuring line 4 through Formula 3. At this time, the moving length detection value L is equal to the zero-residue movement value L2; when the wire wheel 3 rotates n circles, it is only necessary to obtain the number of rotations n of the wire wheel 3 to calculate the moving length detection value L of the measuring line 4 through Formula 2. At this time, the moving length detection value L is equal to the full circle movement value L1; when the wire wheel 3 rotates more than n circles but less than n+1 circles, it is necessary to simultaneously obtain the number of rotations n of the wire wheel 3 and the zero-residue angle γ to calculate the moving length detection value L of the measuring line 4 through Formula 4. At this time, the moving length detection value L is equal to the sum of the full circle movement value L1 and the zero-residue movement value L2.

[0051] In an optional or preferred embodiment, the boom telescopic length detection method includes: obtaining the circumferential angle change value of the wire wheel 3 by using a potentiometer 10 or a Hall sensor. Specifically, when the potentiometer 10 is used, the rotating element of the potentiometer 10 can move with the rotation of the wire wheel 3, thereby changing the potential difference and resistance value of the potentiometer 10. By measuring the change in the resistance value of the potentiometer 10, the circumferential angle change value of the wire wheel 3 can be calculated. When the Hall sensor is used, it is necessary to install a magnet 8 that can rotate synchronously on the wire wheel 3, so that the Hall sensing element 9 is spaced from the magnet 8 so that the Hall sensing element 9 can accurately sense the change in the magnetic field. When the wire wheel 3 rotates, the magnet 8 will rotate accordingly, resulting in a change in the magnetic field. The Hall sensing element 9 will sense this change and output a corresponding electrical signal. By reading and analyzing these electrical signals, the circumferential angle change value of the wire wheel 3 can be calculated. The specific calculation method depends on the number and layout of the magnets 8 and the configuration of the Hall sensing element 9.

[0052] In an optional or preferred embodiment, the boom telescopic length detection method further includes:

[0053] During the length detection period, the circumferential angle change value η of the line collection wheel 2 is obtained. For example, the rotation angle of the line collection wheel 2 can be detected by a potentiometer 10 or a Hall sensor to obtain the circumferential angle change value η;

[0054] The initial winding radius r0 and the final winding radius r1 of the line collection wheel 2 within the length detection period are obtained, and the intermediate winding radius r2 is calculated, wherein the intermediate winding radius r2 satisfies:

[0055] According to the intermediate winding radius and the circumferential angle change of the line collection wheel 2, the estimated moving length L of the measuring line 4 is calculated. g ,satisfy:

[0056] Furthermore, the boom telescopic length detection method further includes:

[0057] In determining the moving length detection value L and the moving length estimation value L g When the calculated difference between the two values ​​falls outside the preset calculation error, an alarm signal is issued to prompt re-measurement, thereby reminding the operator to re-measure the moving length detection value L in time.

[0058] In an optional or preferred embodiment, the boom telescopic length detection method further includes: pushing the clamping wheel 6 to press against the outer wheel rim of the guide wheel 3 by means of a clamping spring.

[0059] Furthermore, the boom telescopic length detection method further includes: the preload force of the compression spring is set so that the angular velocity of the close contact section between the length measuring wire 4 and the wire wheel 3 is kept constant during the length detection period. In other words, the preload force of the compression spring is set so that the friction between the length measuring wire 4 and the wire wheel 3 is large enough so that the linear motion of the length measuring wire 4 can be completely converted into the rotational motion of the wire wheel 3, ensuring that the angular velocity ω of the close contact section of the length measuring wire 4 is kept constant during the length detection period. x Equal to the angular velocity ω of the wire wheel 3 c .

[0060] In an optional or preferred embodiment, the wire collection wheel 2 rotates around the main shaft 5, the wire wheel 3 is mounted on the wire wheel shaft 7, and the length measuring wire 4 can drive the wire wheel 3 and the wire wheel shaft 7 to rotate synchronously; wherein the wire wheel shaft 7 is arranged parallel to and spaced from the main shaft 5. Similarly, by obtaining the circumferential angle change value of the wire wheel shaft 7, and according to the circumferential angle change value of the wire wheel shaft 7, the moving length detection value of the length measuring wire 4 can also be calculated.

[0061] In addition, the measuring wire 4 is wrapped around the line collecting wheel 2. Ideally, the measuring wire 4 is tightly arranged from bottom to top, that is, after one layer is full, it will continue to be wound outside the layer until the free end of the measuring wire 4 is tightened. According to the actual measuring range requirements, 2 to 4 layers are usually wound. In this way, when the measuring wire 4 drives the line collecting wheel 2 to rotate and is pulled out of the line collecting wheel 2, the free end of the measuring wire 4 will produce a certain displacement along the axial direction of the main shaft 5, which will cause the measuring wire 4 to shake, and there is a risk of detaching from the wire wheel 3. To this end, further driven by the moving measuring wire 4, the wire wheel 3 is configured to be able to move along the axial direction of the wire wheel shaft 7, so that the wire wheel 3 can be kept at the same horizontal height as the measuring wire 4 pulled out of the line collecting wheel 2, effectively avoiding the shaking of the pulled out measuring wire 4 and ensuring the stability of the detection process.

[0062] The present application also provides a length detection sensor. In a specific embodiment, see Figures 2 to 4 , the length detection sensor includes a collection wheel assembly and a conductor wheel assembly. Among them, the collection wheel assembly includes a collection wheel 2 for collecting and winding the measuring line 4; the conductor wheel assembly includes a rotation amount conversion component and a conductor wheel 3 and a clamping wheel 6 arranged closely in a pressure roller shape, the conductor wheel 3 can rotate freely, and the rotation amount conversion component is used to measure the circumferential angle change value of the conductor wheel 3. The fixed end of the measuring line 4 is connected to the collection wheel 2, and the free end extends outward through the conductor wheel 3 and the clamping wheel 6 to connect the telescopic end of the boom. The clamping wheel 6 is used to press the measuring line 4 against the outer wheel rim of the conductor wheel 3, and enable the movement of the measuring line 4 to drive the conductor wheel 3 to rotate.

[0063] It can be seen that the length detection sensor in this embodiment can press the free end of the measuring line 4 on the line collection wheel 2 onto the wire wheel 3, so that the measuring line can drive the wire wheel 3 to rotate synchronously when extending or retracting and ensure that there is no slippage between the two, so that the linear speed of the outer rim of the wire wheel 3 is consistent with the moving speed of the measuring line 4, and then the circumferential angle change value of the wire wheel 3 is measured by the rotation amount conversion component and combined with its outer edge circumference data, so as to calculate the moving length of the measuring line 4. In this way, the measured result is more direct and does not need to be corrected. It can also avoid measurement errors caused by misalignment, jumping, accumulation, etc. of the measuring line 4 on the line collection wheel. On the whole, the accuracy of calculating the moving length of the measuring line is greatly improved, thereby realizing accurate feedback on the telescopic length of the boom and improving the safety of the boom operation.

[0064] exist Figure 2 In the embodiment shown, the wire collection wheel 2 rotates around the main shaft 5, the wire wheel 3 is mounted on the wire wheel shaft 7, the wire wheel shaft 7 is arranged parallel to the main shaft 5 and spaced apart, and the length measuring line 4 can drive the wire wheel 3 and the wire wheel shaft 7 to rotate synchronously. Therefore, the circumferential angle change value of the wire wheel shaft 7 detected by the rotation amount conversion component can be converted into the circumferential angle change value of the wire wheel 3.

[0065] In order to realize the smooth rotation of the wire wheel shaft 7, bearings are respectively installed at both ends of the wire wheel shaft 7, the fixed part of the bearing is installed on the mounting frame 1, and the two ends of the wire wheel shaft 7 are respectively connected to the rotating part of the bearing.

[0066] In order to realize synchronous rotation of the wire wheel 3 and the wire wheel shaft 7, an axial long groove can be opened on the wire wheel shaft 7, and correspondingly, a convex key is set on the inner wheel rim of the wire wheel 3, and the key groove is used to cooperate so that the wire wheel 3 can drive the wire wheel shaft 7 to rotate synchronously when it rotates. In addition, the wire wheel 3 moves along the axial long groove by sliding with the convex key, so that when the length measuring line 4 is pulled out of the collection wheel 2 and produces a certain displacement along the axis direction of the main shaft 5, the wire wheel 3 can move along the axial long groove in time, so as to keep it at the same horizontal height as the length measuring line 4 pulled out of the collection wheel 2, effectively avoiding the violent shaking of the length measuring line 4, and ensuring the stability and smoothness of the detection process.

[0067] exist Figure 2 and Figure 3 In the embodiment shown, the wire wheel shaft 7 is installed on the mounting frame 1 in parallel and at intervals with the main shaft 5, a connecting rod is hinged on the mounting frame 1, a clamping wheel 6 is hinged on the free end of the connecting rod, a clamping spring is connected between the connecting rod and the mounting frame 1, and the clamping spring is used to push the clamping wheel 6 to press against the outer wheel rim of the wire wheel 3.

[0068] It can be understood that the preload force of the compression spring is set to keep the angular velocity of the close contact section between the length measuring line 4 and the wire wheel 3 consistent, thereby making the friction between the length measuring line 4 and the wire wheel 3 large enough, and the linear motion of the length measuring line 4 can be completely converted into the rotational motion of the wire wheel 3, ensuring that within the length detection period, the angular velocity of the close contact section of the length measuring line 4 is equal to the angular velocity of the wire wheel 3, effectively avoiding errors in the moving length detection of the length measuring line 4 due to speed loss.

[0069] exist Figure 2 In the embodiment shown, a circumferential limiting groove for limiting the length measuring line 4 is formed on the outer rim of the wire wheel 3. By limiting the length measuring line 4 by the circumferential limiting groove, it is possible to effectively ensure that the length measuring line 4 moves smoothly along the telescopic direction of the boom, and to prevent the length measuring line 4 from being separated from the wire wheel 3 or being offset to affect the smooth progress of the detection. Specifically, for example, when the diameter of the wire wheel 3 is large enough, the outer rim of the wire wheel 3 can be concave to form the above-mentioned circumferential limiting groove; when the diameter of the wire wheel 3 is small, two ring plates arranged in an axial direction can be provided on the outer rim of the wire wheel 3, and the two ring plates and the wire wheel 3 can be used to jointly enclose the above-mentioned circumferential limiting groove. For this reason, in actual application, the specific setting method of the circumferential limiting groove can be determined according to the size of the wire wheel 3, and this application does not limit this.

[0070] exist Figure 2 In the illustrated embodiment, the line collection wheel assembly includes a coil spring disk disposed inside the line collection wheel 2 , which can provide a reverse pre-tightening force for the line collection wheel 2 , thereby facilitating the recovery of the stretched length measuring line 4 .

[0071] exist Figure 2 In the illustrated embodiment, the rotation amount conversion component is a Hall sensor. Specifically, the Hall sensor includes a magnet 8 and a Hall sensing element 9. The magnet 8 is mounted on the end of the wire wheel shaft 7. The Hall sensing element 9 is axially spaced and arranged at the end of the wire wheel shaft 7 and aligned with the magnet 8. When the wire wheel 3 drives the wire wheel shaft 7 to rotate, the magnet 8 will rotate accordingly, resulting in a change in the magnetic field. The Hall sensing element 9 will sense this change and output a corresponding electrical signal. By reading and analyzing these electrical signals, the circumferential angle change value of the wire wheel shaft 7, that is, the circumferential angle change value of the wire wheel 3, can be calculated. The specific calculation method depends on the number and layout of the magnets 8 and the configuration of the Hall sensing element 9.

[0072] exist Figure 4In the illustrated embodiment, the rotation amount conversion component is a potentiometer 10. Specifically, the potentiometer 10 can be fixedly mounted on the end of the wire wheel shaft 7, and the rotating element inside the potentiometer 10 can move with the rotation of the wire wheel shaft 7, thereby changing the potential difference and resistance value of the potentiometer 10. By measuring the change in the resistance value of the potentiometer 10, the circumferential angle change value of the wire wheel shaft 7, that is, the circumferential angle change value of the wire wheel 3, can be calculated.

[0073] In other embodiments, the rotation amount conversion component may also be an encoder (not shown in the drawings), preferably an incremental encoder may be used to continuously measure the angle change of the wire wheel 3. The encoder may be arranged at the end of the wire wheel shaft 7, and when the encoder rotates a certain angle, a certain number of pulses will be generated. By calculating the number of received pulses, the circumferential angle change value of the wire wheel shaft 7 can be calculated, and thus can be converted into the circumferential angle change value of the wire wheel 3.

[0074] The present application also provides a telescopic boom, which includes the above-mentioned length detection sensor. Obviously, the telescopic boom has all the technical effects brought by the above-mentioned length detection sensor, so they will not be repeated here.

[0075] In practical applications, the telescopic boom may be a telescopic boom of a crane or a telescopic boom of other engineering machinery, and this application does not limit this.

[0076] In the description of the present application, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of the present application, "plurality" means at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0077] In this application, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, or communication with each other; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0078] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0079] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations on the present application. Ordinary technicians in this field can change, modify, replace and modify the above embodiments within the scope of the present application.

Claims

1. A length detection sensor, characterized in that: The length detection sensor comprises: The line collection wheel assembly comprises a line collection wheel (2) for collecting and winding the long measuring line (4); A wire wheel assembly, comprising a rotation amount conversion component and a wire wheel (3) and a pressure wheel (6) arranged adjacent to each other in the shape of a pressure roller, wherein the wire wheel (3) can rotate freely, and the rotation amount conversion component is used to measure the circumferential angle change value of the wire wheel (3); The free end of the length measuring wire (4) extends outward through between the guide wheel (3) and the clamping wheel (6), and the clamping wheel (6) is used to press the length measuring wire (4) against the outer wheel rim of the guide wheel (3), so that the movement of the length measuring wire (4) can drive the guide wheel (3) to rotate.

2. The length detection sensor according to claim 1, characterized in that: The line collecting wheel (2) rotates around the main shaft (5), the wire wheel (3) is mounted on the wire wheel shaft (7), the wire wheel shaft (7) is arranged parallel to the main shaft (5) and spaced apart, and the length measuring line (4) can drive the wire wheel (3) and the wire wheel shaft (7) to rotate synchronously.

3. The length detection sensor according to claim 2, characterized in that: Bearings are respectively installed at both ends of the wire wheel shaft (7).

4. The length detection sensor according to claim 2, characterized in that: The guide wheel shaft (7) is provided with an axial long groove, the inner wheel rim of the guide wheel (3) is provided with a convex key, and the guide wheel (3) moves along the axial long groove in a sliding manner through the convex key.

5. The length detection sensor according to claim 2, characterized in that: The guide wheel shaft (7) is installed on the mounting frame (1) in parallel and at intervals with the main shaft (5); a connecting rod is hinged on the mounting frame (1); the pressure wheel (6) is hinged on the free end of the connecting rod; a pressure spring is connected between the connecting rod and the mounting frame (1); the pressure spring is used to push the pressure wheel (6) to press against the outer wheel rim of the guide wheel (3).

6. The length detection sensor according to claim 5, characterized in that: The preload force of the compression spring is set so that the angular velocity of the close contact section between the length measuring wire (4) and the guide wheel (3) remains constant.

7. The length detection sensor according to claim 2, characterized in that: A circumferential limiting groove for limiting the position of the length measuring wire (4) is formed on the outer wheel rim of the guide wheel (3).

8. The length detection sensor according to claim 2, characterized in that: The line collection wheel assembly comprises a winding spring disc arranged inside the line collection wheel (2).

9. The length detection sensor according to any one of claims 2 to 8, characterized in that: The rotation amount conversion component is at least one of a potentiometer (10) and an encoder; Alternatively, the rotation amount conversion component comprises a magnet (8) and a Hall sensor element (9), wherein the magnet (8) is mounted on the end of the wire wheel shaft (7), and the Hall sensor element (9) is arranged axially at intervals at the end of the wire wheel shaft (7) and is aligned with the magnet (8) at intervals.

10. A telescopic boom, characterized in that: The telescopic boom comprises a length detection sensor according to any one of claims 1 to 9.

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