Test bed and test method for fatigue life of steel cable of aircraft control system

Abstract

The invention discloses a test bed and a test method for fatigue life of a steel cable of an aircraft control system, in the test bed, a first hollow guide rail 2a for mounting a test pulley 8 is arranged at the upper part of a mounting bottom plate 3 of a support frame along a longitudinal center line, and two second hollow guide rails 2b for the second hollow guide rails 2b are symmetrically arranged along a transverse center line; a driving pulley in the driving control system is mounted at the bottom of the longitudinal center line of the mounting bottom plate 3; after the test steel cable 1 bypasses the test pulley 8 and the two auxiliary pulleys 13, the two ends of the test steel cable 1 are respectively connected with the two ends of the driving steel cable 11 wound on the driving pulley 12 through one tension regulator 10 to form a steel cable loop, and the driving steel cable 11 is fixedly connected with the driving pulley 12; the test bed adjusts the pulley wrap angle of the test steel cable 1 wound on the test pulley 8 through the mounting positions of the two auxiliary pulleys 13 and the test pulley 8 on the mounting bottom plate 3, and drives the test steel cable 1 to reciprocate around the test pulley 8 through the driving of the driving control system to the driving pulley 12, so as to perform a fatigue life test on the steel cable test piece. According to the technical scheme provided by the invention, the problems that the fatigue life of the steel cable under various working conditions needs to be obtained through a test mode due to the fact that the existing fatigue life test of the steel cable in the soft control system relates to the steel cable under various working conditions, the test workload is huge, and the cost input is relatively large are solved.

Description

Technical Field

[0001] The present invention relates to the field of ground test technology in aircraft design, but is not limited to it, and in particular to a test bench and a test method for fatigue life of steel cables in aircraft control systems. Background Art

[0002] The soft control system in the mechanical flight control system is also called the cable control system. It is a system that transmits mechanical control movements through flexible cables. It usually includes cable components, pulleys, rocker arms, and connectors. In order to ensure the safety of the soft control system during aircraft design, it is necessary to carry out life calculation and verification of the soft control system.

[0003] The life of the soft control system is mainly affected by the life of the cable loop system, and the life of other components in the cable loop system other than the cable is much longer than the life of the cable. Therefore, the life of the soft control system mainly depends on the fatigue life of the cable in the soft control system. Since the fatigue life of the cable in the soft control system is affected by many factors such as the pulley material, cable diameter, pulley diameter, system tension and pulley wrap angle, it can be considered that each soft control system contains cables under various working conditions. To obtain the fatigue life of the cable under various working conditions through testing, the test workload is huge and the cost investment is large. Summary of the invention

[0004] Purpose of the present invention: In order to solve the above-mentioned technical problems, the embodiments of the present invention provide a test bench and a test method for the fatigue life of steel cables in an aircraft control system, so as to solve the problem that the existing fatigue life test of steel cables in a soft control system involves steel cables in various working conditions, and the fatigue life of steel cables under various working conditions must be obtained through tests, which results in a huge workload and high cost investment.

[0005] Technical solution of the present invention: In a first aspect, an embodiment of the present invention provides a test bench for fatigue life of steel cables of an aircraft control system, comprising: a support frame, two auxiliary pulleys 13, a drive control system, and two tension regulators;

[0006] The support frame includes a support base 4 and a mounting base plate 3 installed on the upper end of the support base 4. A first hollow guide rail 2a is provided on the upper portion of the mounting base plate 3 along the longitudinal center line, and two second hollow guide rails 2b are symmetrically provided along the transverse center line, for installing a test pulley 8 through the first hollow guide rail 2a, and installing two auxiliary pulleys 13 through two symmetrically arranged second hollow guide rails 2b, and a driving pulley in a driving control system is installed at the bottom of the longitudinal center line of the mounting base plate 3;

[0007] After the test cable 1 passes around the test pulley 8 and the two auxiliary pulleys 13, the driving cable 11 passes around the driving pulley 12, and the driving cable 11 is fixedly connected with the driving pulley 12. The two ends of the test cable 1 are connected to the corresponding two ends of the driving cable 11 through a tension regulator 10 to form a cable loop.

[0008] The test bench for the fatigue life of the steel cable of the aircraft control system is used to adjust the pulley wrap angle of the test pulley 8 around the test steel cable 1 through the installation positions of the two auxiliary pulleys 13 and the test pulley 8 on the installation base plate 3, and drive the test steel cable 1 to reciprocate around the test pulley 8 by driving the driving pulley 12 through the drive control system, so as to perform a fatigue life test on the steel cable test piece.

[0009] Optionally, the test bench for fatigue life of steel cables of an aircraft control system as described above further comprises: three pulley mounting bases, namely, a test pulley mounting base 5 and two auxiliary pulley mounting bases 6;

[0010] The mounting base plate 3 mounts a test pulley 8 by slidingly nesting a test pulley mounting base 5 in the first hollow guide rail 2a, and mounts an auxiliary pulley 13 by slidingly nesting an auxiliary pulley mounting base 6 in each second hollow guide rail 2b;

[0011] The distances between the center lines of the pulley grooves of the test pulley 8, the two auxiliary pulleys 13 and the driving pulley 12 and the mounting base plate 3 are the same.

[0012] Optionally, in the test bench for fatigue life of steel cables of aircraft control systems as described above, each pulley mounting base comprises: a manual adjustment knob 14, a screw 17 fixedly arranged at one end of the manual adjustment knob, after a bushing is inserted into the central bearing of the test pulley 8 or the auxiliary pulley 13, the test pulley 8 or the auxiliary pulley 13 is sleeved on the screw 17 together with the bushing, and the distance between the test pulley 8 or the auxiliary pulley 13 and the mounting base 3 is adjusted by the screw 17, and the test pulley 8 or the auxiliary pulley 13 is fixed on the screw 17 together with the bushing by two adjusting nuts 16 sleeved on the screw 17 and located on both sides of the pulley;

[0013] Each pulley mounting base has its screw rod 17 passing through the second hollow guide rail 2b, and the screw rod 17 is located on both sides of the mounting base plate 3 and is screwed with flange nuts 15; after the three pulley mounting bases are slid and adjusted to the specified position, two flange nuts 15 are used to fix the base position to fix the longitudinal position of the test pulley 8 or the lateral position of the auxiliary pulley 13;

[0014] The length of the bushing used is slightly greater than the bearing thickness of the test pulley 8 or the auxiliary pulley 13 to ensure that the test pulley 8 or the auxiliary pulley 13 can rotate freely after being fixed.

[0015] Optionally, in the test bench for fatigue life of steel cables of aircraft control systems as described above, the drive control system comprises: a drive pulley 12, a drive steel cable 11, a stepper motor 18 and a motor encoder controller 22;

[0016] Among them, the central axis of the driving pulley 12 is tightly fitted on the output shaft 18a of the stepper motor 18, and the driving pulley 12 is driven to rotate by the output shaft 18a of the stepper motor 18. The position of the driving pulley 12 on the output shaft 18a of the stepper motor 18 is fixed by two adjusting nuts 16 screwed on the output shaft 18a and located on both sides of the driving pulley 12; the motor encoding controller 22 controls the stepper motor 18 to drive the driving pulley 12 to reciprocate through a preset program, so that the driving pulley 12 drives the test steel cable 1 to reciprocate through the driving steel cable 11 fixed thereon.

[0017] Optionally, in the test bench for fatigue life of steel cables of aircraft control systems as described above,

[0018] Each tension adjuster 10 includes: an adjustable tensioning screw sleeve 21, and steel cable connecting ends connected to both ends of the adjustable tensioning screw sleeve 21, and the steel cable connecting ends at both ends are respectively fixedly connected to one end of the driving steel cable 11 and the test steel cable 1, and the steel cable tension in the test steel cable loop is adjusted by adjusting the tightness of the tensioning screw sleeve 21.

[0019] Optionally, the test bench for fatigue life of steel cables of aircraft control systems as described above further comprises: a recording and display system; three cable displacement sensors 9, a counting sensor 19, a counting induction magnet 20, and a display connected to the three cable displacement sensors 9 and the counting sensor 19 respectively;

[0020] Three wire-drawing displacement sensors 9 are fixedly mounted on the mounting base plate 3 and are correspondingly located at the ends of the three hollow guide rails. The wire-drawing end of the wire-drawing displacement sensor 9 is connected to the screw 17 of the test pulley mounting base 5 or the auxiliary pulley mounting base 6 on the hollow guide rail on which it is mounted. The three wire-drawing displacement sensors 9 are used to measure the distance position information of the three pulley mounting bases and display it on a display; wherein, the distance position information of the three pulley mounting bases is used to characterize the position distance information of the test pulley 8 and the two auxiliary pulleys;

[0021] The counting sensor 19 is fixedly mounted on the mounting base plate 3 at the position where the driving pulley 12 is mounted, the counting induction magnet 20 is fixed on the side of the driving pulley 12 facing the mounting base plate, and the counting sensor 19 and the counting induction magnet 20 are arranged opposite to each other, and the counting induction magnet 19 and the counting induction magnet 20 are used to record the number of reciprocating motions of the test rope 1 and display them on the display.

[0022] In a second aspect, an embodiment of the present invention further provides a test method for fatigue life of a steel cable of an aircraft control system, wherein a fatigue life test method is performed on a steel cable component to be tested using a test bench for fatigue life of a steel cable of an aircraft control system as described in any one of the above, wherein the steel cable test piece to be tested comprises: a test steel cable 1 and a test pulley 8; the fatigue life test method comprises:

[0023] Step 1, before the test, determine the test pulley 8, the test steel cable 1, the steel cable tension, the test pulley wrap angle and the steel cable movement frequency according to the test requirements;

[0024] Step 2, installing the test pulley 8 and two auxiliary pulleys 13 on the mounting base plate 3 of the support frame, and adjusting the position distance between the test pulley 8 and the two auxiliary pulleys according to the wrap angle of the test pulley;

[0025] Step 3, based on the distance between the center line of the pulley groove of the auxiliary pulley 13 and the installation base plate 3, adjust the installation distance between the test pulley 8 and the installation base plate 3;

[0026] Step 4, adjust the cable tension, after passing both ends of the test cable 1 around the test pulley 8 and the two auxiliary pulleys 13, the two ends are connected to the corresponding ends of the drive cable 11 through two tension adjusters 10, and then the adjustable tension screw sleeve 21 on the tension adjuster 10 is tightened until the cable tension reaches the tension value required by the test, forming a test cable loop;

[0027] Step 5, execute fatigue test, input the cable movement frequency required by the test into the motor encoder controller 22, start the stepper motor 18 to drive the entire cable loop to reciprocate according to a given program, and the test cable 1 performs reciprocating fatigue motion at the test pulley 8 according to the cable tension, pulley wrap angle and movement frequency required by the test, simulating the movement state on the aircraft, and completes the cycle counting of each movement through the counting sensor 19 and the counting induction magnet 20, and displays the record on the display.

[0028] Optionally, in the above-mentioned test method for fatigue life of steel cables of an aircraft control system, step 2 comprises:

[0029] Adjust the positions of the test pulley mounting base 5 and the auxiliary pulley mounting base 6 and fix them. First, calculate and determine the plane relative position coordinates of the test pulley 8 and the two auxiliary pulleys 6 according to the pulley wrap angle, the test pulley 8 diameter size, and the auxiliary pulley 6 diameter size specified in the test requirements. Then, slide the test pulley mounting base 5 and the two auxiliary pulley mounting bases 6 on the corresponding hollow guide rails to the corresponding coordinate positions. During the adjustment process, measure and observe the distance values ​​through the pull-wire displacement sensor 9 and the display to ensure the accuracy of the coordinate positions of the three pulley mounting bases. Finally, fix the test pulley mounting base 5 and the two auxiliary pulley mounting bases 6 on the mounting base plate 3 through the flange nut 15.

[0030] Optionally, in the above-mentioned test method for fatigue life of steel cables of an aircraft control system, step 3 comprises:

[0031] Based on the distance between the center line of the pulley groove of the auxiliary pulley 13 and the mounting base plate 3, and on the premise of ensuring that the center line of the pulley groove of the test pulley 8 coincides with the center line of the pulley groove of the driving pulley 12, the distance between the end face of the test pulley 8 and the mounting base plate 3 is calculated according to the thickness of the test pulley 8. After installing and adjusting the position of the test pulley 8, the test pulley 8 is fixed together with the bushing to the corresponding position on the screw 17 in the test pulley mounting base 5 through two adjusting nuts 16.

[0032] Optionally, in the above-mentioned test method for fatigue life of steel cables of aircraft control systems,

[0033] In the step 5, during the fatigue test, the test steel cable 1 is subjected to reciprocating motion by the test bench until the test steel cable 1 is damaged by wire or strand breakage, and the number of motion cycles recorded on the display is read as the life of the steel cable; or, based on the number of reciprocating motions of the steel cable given in the fatigue test, the condition of the test steel cable 1 is detected after the test steel cable 1 is subjected to a corresponding number of reciprocating motions.

[0034] Beneficial effects of the present invention: The embodiment of the present invention provides a test bench and a test method for the fatigue life of a steel cable of an aircraft control system, in which a first hollow guide rail 2a for installing a test pulley 8 is provided on the upper portion of a mounting base plate 3 of a support frame along the longitudinal center line, and two second hollow guide rails 2b for installing a second hollow guide rail 2b are symmetrically provided along the transverse center line, and a driving pulley in a driving control system is installed at the bottom of the longitudinal center line of the mounting base plate 3; after the test steel cable 1 passes around the test pulley 8 and two auxiliary pulleys 13, its two ends are respectively connected to the two ends of a driving steel cable 11 wound on a driving pulley 12 through a tension regulator 10 to form a steel cable loop, and the driving steel cable 11 is fixedly connected to the driving pulley 12 at one point. By using the test bench provided by the embodiment of the present invention, on the one hand, the pulley wrap angle of the test pulley 8 around the test steel cable 1 can be adjusted by the installation positions of the two auxiliary pulleys 13 and the test pulley 8 on the installation base plate 3; on the other hand, the test steel cable 1 can be driven to reciprocate around the test pulley 8 by the driving control system through the driving of the driving pulley 12, so as to perform fatigue life test on the steel cable test piece. The technical solution provided by the present invention has the following beneficial effects:

[0035] (1) The present invention uses a test bench and test method independently developed for fatigue life test of control system cables, which can simulate the working conditions of control system cables on aircraft, and combine the movement speed and movement frequency of control system cables on aircraft to set a drive control process, automatically complete the fatigue life test of control system cables and test records, greatly improving the test efficiency;

[0036] (2) The test bench provided by the present invention can simulate the working conditions of the control system cables under all common factors such as pulley materials, cable diameters, pulley diameters, system tensions and pulley wrap angles in aircraft control systems, and can be reused, effectively saving test costs; the test bench has a simple and practical structure, is easy and intuitive to operate, and has promotion value. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] The accompanying drawings are used to provide a further understanding of the technical solution of the present invention and constitute a part of the specification. Together with the embodiments of the present application, they are used to explain the technical solution of the present invention and do not constitute a limitation on the technical solution of the present invention.

[0038] Figure 1 A front view of a test bench for fatigue life of steel cables of an aircraft control system provided by an embodiment of the present invention;

[0039] Figure 2 for Figure 1 A side view of a test bench for fatigue life of steel cables of an aircraft control system provided by the illustrated embodiment;

[0040] Figure 3 To adopt Figure 1The embodiment shown shows a front view of a test bench installed with a pulley wrap angle of 180°;

[0041] Figure 4 To adopt Figure 1 The embodiment shown shows a front view of the test bench installed with a pulley wrap angle of 0°;

[0042] Figure 5 for Figure 1 A schematic diagram of the installation of a pulley mounting base in a test bench provided in the illustrated embodiment;

[0043] Figure 6 for Figure 1 A schematic diagram of the installation of a drive system in a test bench provided by the illustrated embodiment;

[0044] Figure 7 for Figure 1 A schematic structural diagram of a tension regulator in a test bench provided in the illustrated embodiment;

[0045] Figure 8 A schematic diagram of the layout of the display system panels is provided for recording;

[0046] Fig. 9 Schematic diagram of the adjustment principle of two auxiliary pulleys arranged in a symmetrical structure in an embodiment of the present invention;

[0047] Fig.10 Schematic diagram of the adjustment principle of two auxiliary pulleys arranged in an asymmetric structure in an embodiment of the present invention.

[0048] Description of reference numerals:

[0049] 1 test steel cable, 2a first hollow guide rail, 2b second hollow guide rail, 3 mounting base, 4 support base, 5 test pulley mounting base, 6 auxiliary pulley mounting base, 8 test pulley, 9 wire displacement sensor, 10 tension regulator, 11 drive steel cable, 12 drive pulley, 13 auxiliary pulley, 14 manual adjustment knob, 15 flange nut, 16 adjustment nut, 17 screw, 18 stepper motor, 18a stepper motor output shaft, 19 counting sensor, 20 counting induction magnet, 21 adjustable tensioning screw sleeve, 22 motor encoding controller, 23 displacement display, 24 counting display, 25 main power switch. DETAILED DESCRIPTION

[0050] In order to make the purpose, technical solution and advantages of the present invention more clear, the embodiments of the present invention will be described in detail with reference to the accompanying drawings. It should be noted that the embodiments and features in the embodiments of the present application can be combined with each other arbitrarily without conflict.

[0051] The above background technology has explained the necessity of conducting fatigue life tests on the soft control system in the mechanical flight control system; since the fatigue life of the steel cable in the soft control system is affected by many factors such as the pulley material, steel cable diameter, pulley diameter, system tension and pulley wrap angle, it can be considered that each soft control system contains steel cables under various working conditions. Therefore, in order to obtain the fatigue life of the steel cables under various working conditions through experiments, the experimental workload is huge and the cost investment is relatively large.

[0052] Therefore, it is necessary to design an efficient and reliable fatigue test method and test bench to improve test efficiency, shorten test cycle and reduce test cost.

[0053] In view of the above problems and needs, an embodiment of the present invention provides a test bench and a test method for the fatigue life of steel cables of an aircraft control system.

[0054] The present invention provides the following specific embodiments which can be combined with each other, and the same or similar concepts or processes may not be described in detail in some embodiments.

[0055] Figure 1 It is a front view of a test bench for fatigue life of steel cables of an aircraft control system according to an embodiment of the present invention; Figure 2 for Figure 1 The illustrated embodiment provides a side view of a test bench for fatigue life of steel cables of an aircraft control system.

[0056] The components of the test bench for fatigue life of steel cables of aircraft control systems provided in the embodiment of the present invention may include: a support frame, a test pulley mounting base 5, an auxiliary pulley mounting base 6, a drive control system, a recording and display system, two tension regulators 10 and two auxiliary pulleys 13. The specific structures and functions of the above components in the test bench provided in the embodiment of the present invention are described in detail as follows:

[0057] 1) The test piece in the embodiment of the present invention includes a test steel cable 1 and a test pulley 8; wherein the test steel cable 1 is passed around the test pulley 8 and two auxiliary pulleys 13, the driving steel cable 11 is passed around the driving pulley 12, and the center of the driving steel cable 11 is fixed on the driving pulley 12, and the two ends of the test steel cable 1 are connected to the corresponding two ends of the driving steel cable 11 through a tension regulator 10 respectively.

[0058] 2) The support frame is a steel frame structure, including a support base 4 and a mounting base plate 3. The support base 4 is used to fix the mounting base plate 3 and ensure that it is not deformed by force. Three hollow guide rails 2 are left on the mounting base plate 3, namely: a first hollow guide rail 2a is opened along the longitudinal center line of the upper part of the mounting base plate 3, and two second hollow guide rails 2b are symmetrically opened along the transverse center line. The first hollow guide rail 2a is used for sliding adjustment and fixing of the test pulley 8, and the two symmetrically arranged second hollow guide rails 2b are used for sliding adjustment and fixing of two auxiliary pulleys 13;

[0059] In addition, the driving pulley in the driving control system is installed at the bottom of the longitudinal center line of the mounting base plate 3, and the mounting base plate 3 is used to install the programmable stepping motor 18, the counting sensor 19 and the wire displacement sensor 8;

[0060] The mounting base plate 3 is also used for fixing and mounting some components of the driving system and the recording and display system.

[0061] 3) The test pulley mounting base 5 includes a manual adjustment knob 14 and a screw 17 fixedly arranged at one end of the manual adjustment knob. After a bushing is inserted into the center bearing of the test pulley 8, the test pulley 8 together with the bushing is inserted onto the screw 17, and then the distance between the test pulley 8 and the mounting base plate 3 is adjusted by the screw 17. Subsequently, the test pulley 8 together with the bushing is fixed to the screw 17 by two adjusting nuts 16 to maintain the distance between the test pulley 8 and the mounting base plate 3. The length of the bushing used is slightly larger than the thickness of the bearing of the test pulley 8 to ensure that the test pulley 8 can rotate freely after being fixed. The test pulley mounting base 5 passes through the first hollow guide rail 2a with its screw 17. The screw 17 is located on both sides of the mounting base plate 3 and is screwed with flange nuts 15. After the test pulley mounting base 5 is slid and adjusted to the specified position, it is fixed with two flange nuts 15 to fix the longitudinal position of the test pulley 8. During the process of adjusting the position of the test pulley mounting base 5, the position distance information of the test pulley 8 is measured and observed through the wire displacement sensor 9 and the displacement display 22.

[0062] 4) Two auxiliary pulley mounting bases 6 are provided, each of which includes a manual adjustment knob 14 and a screw 17 fixedly provided at one end of the manual adjustment knob. After a bushing is inserted into the center bearing of the test pulley 8, the test pulley 8 together with the bushing is inserted onto the screw 17, and then the distance between the auxiliary pulley 13 and the mounting base 3 is adjusted. Subsequently, the auxiliary pulley 13 together with the bushing is fixed to the screw 17 by two adjusting nuts 16. The length of the bushing used is slightly larger than the thickness of the bearing of the auxiliary pulley 13 to ensure that the auxiliary pulley 13 can rotate freely after being fixed. The auxiliary pulley mounting base 6 passes through the second hollow guide rail 2b with its screw 17. The screw 17 is located on both sides of the mounting base plate 3 and is screwed with flange nuts 15. After the test pulley mounting base 5 is slid and adjusted to the specified position, it is fixed with two flange nuts 15 to fix the lateral position of the auxiliary pulley 13. During the process of adjusting the position of the auxiliary pulley mounting base 6, the position distance information of the auxiliary pulley 13 is also measured and observed through the wire displacement sensor 9 and the displacement display 22.

[0063] 5) The driving control system includes: a driving pulley 12, a driving steel cable 11, a stepping motor 18 and a motor encoding controller 22. The central axis of the driving pulley 12 is fitted on the output shaft 18a of the stepping motor 18, and the driving pulley 12 is driven to rotate by the stepping motor 18. The position of the driving pulley 12 on the output shaft 18a of the stepping motor 18 is fixed by two adjusting nuts 16 screwed on the output shaft 18a. The motor encoding controller 22 controls the stepping motor 18 to drive the driving pulley 12 to rotate through a preset program, and the driving pulley 12 drives the test steel cable 1 to reciprocate through the driving steel cable 11 fixed thereon.

[0064] 6) The recording and display system includes: a wire displacement sensor 9, a displacement display 23, a counting sensor 19, a counting induction magnet 20, a counting display 24 and a main power supply.

[0065] Three wire displacement sensors 9 are fixedly mounted on the mounting base plate 3 at the ends of the three hollow guide rails 2, and the wire ends of the wire displacement sensors 9 are fixed on the screw rods 17 of the corresponding bases. The wire displacement sensors 9 and the displacement display 23 are used to measure and display the distance position information of the three pulley mounting bases;

[0066] The counting sensor 19 is fixedly mounted on the mounting base plate 3 at the position where the driving pulley 12 is mounted, the counting induction magnet 20 is fixed on the side of the driving pulley 12 facing the mounting base plate, and the counting sensor 19 and the counting induction magnet 20 are arranged opposite to each other, the counting induction magnet 19, the counting induction magnet 20 and the counting display 24 are used to record and display the number of reciprocating motions of the test steel cable; the main power supply is controlled by the main power switch 25 to provide power to the programmable stepping motor 18, the motor encoding controller 22, the wire displacement sensor 9, the displacement display 23, the counting sensor 19 and the counting display 24.

[0067] 7) Each tension adjuster 10 includes: an adjustable tensioning screw sleeve 21, and steel cable connecting ends connected to both ends of the adjustable tensioning screw sleeve 21, and the steel cable connecting ends at both ends are respectively fixedly connected to the driving steel cable 11 and the test steel cable 1, and the steel cable tension in the test steel cable loop can be adjusted by adjusting the tightness of the tensioning screw sleeve 21.

[0068] Based on the test bench for fatigue life of steel cables of aircraft control systems provided by the above embodiments of the present invention, the embodiments of the present invention further provide a test method for fatigue life of steel cables of aircraft control systems, wherein the test bench for fatigue life of steel cables of aircraft control systems provided by any of the above embodiments is used to perform a fatigue life test method on a steel cable assembly to be tested, wherein the steel cable test piece to be tested includes: a test steel cable 1 and a test pulley 8; the fatigue life test method provided by the embodiments of the present invention includes:

[0069] Step 1, before the test, determine the given parameters such as the test pulley 8, the test cable 1, the system tension, the test pulley wrap angle and the cable movement frequency (reflected by the movement speed per unit time) according to the test requirements.

[0070] Step 2, adjusting and fixing the positions of the test pulley mounting base 5 and the auxiliary pulley mounting base 6;

[0071] The implementation method of this step is: first, the plane relative position coordinates of the test pulley 8 and the two auxiliary pulleys 6 are calculated and determined according to the pulley wrap angle, the diameter size of the test pulley 8, and the diameter size of the auxiliary pulley 6 given by the test requirements, and then the test pulley mounting base 5 and the two auxiliary pulley mounting bases 6 are slid and adjusted to the corresponding coordinate positions on the corresponding hollow guide rails 2. During the adjustment process, the distance value is measured and observed by the pull-wire displacement sensor 9 and the displacement display 22 to ensure the accuracy of the coordinate position. Finally, the test pulley mounting base 5 and the two auxiliary pulley mounting bases 6 are fixed to the mounting base 3 by the flange nuts 15 respectively.

[0072] Step 3, installing the test pulley 8;

[0073] The implementation method of this step is as follows: it includes: based on the distance between the center line of the pulley groove of the auxiliary pulley 13 and the mounting base plate 3, on the premise of ensuring that the center line of the pulley groove of the test pulley 8 and the center line of the pulley groove of the driving pulley 12 coincide with each other, the distance between the end face of the test pulley 8 and the mounting base plate 3 is calculated according to the thickness of the test pulley 8, after installing and adjusting the position of the test pulley 8, the test pulley 8 is fixed together with the bushing to the corresponding position on the screw 17 in the test pulley mounting base 5 by two adjusting nuts 16.

[0074] Step 4: After the installation of the test cable 1 is completed, adjust the cable tension.

[0075] The implementation method of this step is: first, the test steel cable 1 with rolled ends at both ends is passed around the test pulley 8 and two auxiliary pulleys 13, and then the two ends are connected to the corresponding two ends of the driving steel cable 11 through two tension adjusters 10, and then the adjustable tensioning screw sleeve 21 on the tension adjuster 10 is tightened until the tension of the steel cable reaches the tension value required by the test, forming a test steel cable loop.

[0076] Step 5, complete the adjustment of the drive control system and the recording and display system.

[0077] In this step, first turn on the main power switch 25 to supply power to the entire test bench, then input the cable movement frequency required by the test into the motor encoder controller 22, and then press the reset button on the count display 24 to complete the count reset.

[0078] Step 6: Perform fatigue life test on the steel cable test piece.

[0079] The implementation method of this step is: turn on the start button on the motor encoder controller 22, the programmable stepper motor 18 drives the entire cable loop to reciprocate according to a given program, and the test cable 1 performs reciprocating fatigue motion at the test pulley 8 according to the cable tension, pulley wrap angle and motion frequency required by the test, simulating the motion state on the aircraft, and at the same time, each motion cycle is counted through the counting sensor 19 and the counting induction magnet 20, and the record is displayed on the counting display 24.

[0080] During the fatigue test in step 6, the test cable 1 is reciprocated by the test bench until the test cable 1 is damaged by wire or strand breakage, and the number of movement cycles recorded on the counting display 24 is read as the cable life. Optionally, based on the number of reciprocating movements of the cable given in the fatigue test, the condition of the test cable 1 is detected after the test cable is reciprocated for a corresponding number of times.

[0081] An embodiment of the present invention provides a test bench and a test method for fatigue life of a steel cable of an aircraft control system. In the test bench, a first hollow guide rail 2a for installing a test pulley 8 is opened along the longitudinal center line on the upper portion of a mounting base plate 3 of a support frame, and two second hollow guide rails 2b for installing a second hollow guide rail 2b are symmetrically opened along the transverse center line, and a driving pulley in a driving control system is installed at the bottom of the longitudinal center line of the mounting base plate 3; after the test steel cable 1 passes around the test pulley 8 and two auxiliary pulleys 13, its two ends are respectively connected to the two ends of a driving steel cable 11 wound around a driving pulley 12 through a tension regulator 10 to form a steel cable loop, and the driving steel cable 11 is fixedly connected to the driving pulley 12 at one point. By using the test bench provided by the embodiment of the present invention, on the one hand, the pulley wrap angle of the test pulley 8 around the test steel cable 1 can be adjusted by the installation positions of the two auxiliary pulleys 13 and the test pulley 8 on the installation base plate 3; on the other hand, the test steel cable 1 can be driven to reciprocate around the test pulley 8 by the driving control system through the driving of the driving pulley 12, so as to perform fatigue life test on the steel cable test piece. The technical solution provided by the present invention has the following beneficial effects:

[0082] (1) The present invention uses a test bench and test method independently developed for fatigue life test of control system cables, which can simulate the working conditions of control system cables on aircraft, and combine the movement speed and movement frequency of control system cables on aircraft to set a drive control process, automatically complete the fatigue life test of control system cables and test records, greatly improving the test efficiency;

[0083] (2) The test bench provided by the present invention can simulate the working conditions of the control system cables under all common factors such as pulley materials, cable diameters, pulley diameters, system tensions and pulley wrap angles in aircraft control systems, and can be reused, effectively saving test costs; the test bench has a simple and practical structure, is easy and intuitive to operate, and has promotion value.

[0084] Further, the design principle of providing two auxiliary pulleys 13 in the embodiment of the present invention is described as follows:

[0085] The pulley wrap angle refers to the angle between the two points on the pulley that are tangent to the steel cable (the contact part between the pulley and the steel cable). It is an important indicator in the design process of the steel cable assembly and a key parameter that affects the life of the steel cable. The test has a specific pulley wrap angle, so the pulley wrap angle in the test assembly to be tested is required to be consistent with the pulley wrap angle in the actual on-board application scenario. Therefore, two auxiliary pulleys 13 are designed to meet the requirements of the test bench for the pulley wrap angle.

[0086] Example 1 is described by taking two auxiliary pulleys 13 as a symmetrical structure as an example. Fig. 9 Schematic diagram of the adjustment principle of two auxiliary pulleys arranged in a symmetrical structure in an embodiment of the present invention.

[0087] When the test requires a wrap angle of 60°, a symmetrical adjustment method can be used. At the same time, the plane relative position coordinates of the test pulley 8 and the two auxiliary pulleys 6 are calculated and determined according to the diameter size of the test pulley 8 and the diameter size of the auxiliary pulley 6. The positions of the two auxiliary pulleys 13 are adjusted as shown in the figure, so that the angle of the contact part between the adjusted test steel rope 1 and the test pulley 8 is 60°, that is, the wrap angle of 60° required by the test is achieved.

[0088] Example 2 is described by taking the two auxiliary pulleys 13 as an asymmetric structure as an example. Fig.10 Schematic diagram of the adjustment principle of two auxiliary pulleys arranged in an asymmetric structure in an embodiment of the present invention.

[0089] When the test requires a wrap angle of 90°, an asymmetric adjustment method can be used. At the same time, the plane relative position coordinates of the test pulley 8 and the two auxiliary pulleys 6 are calculated and determined according to the diameter size of the test pulley 8 and the diameter size of the auxiliary pulley 6. The positions of the two auxiliary pulleys 13 are adjusted as shown in the figure, so that the angle of the contact part between the adjusted test steel rope 1 and the test pulley 8 is 90°, that is, the wrap angle of 90° required by the test is achieved.

[0090] Although the embodiments disclosed in the present invention are as above, the contents are only embodiments adopted to facilitate understanding of the present invention and are not intended to limit the present invention. Any technician in the field to which the present invention belongs can make any modifications and changes in the form and details of implementation without departing from the spirit and scope disclosed in the present invention, but the patent protection scope of the present invention shall still be subject to the scope defined in the attached claims.

Claims

1. A test bench for fatigue life of steel cables of aircraft control systems, characterized in that: include: Support frame, 2 auxiliary pulleys (13), drive control system, 2 tension regulators; The support frame comprises a support base (4) and a mounting base plate (3) mounted on the upper end of the support base (4); a first hollow guide rail (2a) is provided on the upper portion of the mounting base plate (3) along the longitudinal center line, and two second hollow guide rails (2b) are symmetrically provided along the transverse center line, for mounting a test pulley (8) through the first hollow guide rail (2a), and mounting two auxiliary pulleys (13) through the two symmetrically arranged second hollow guide rails (2b); and a driving pulley in a driving control system is mounted at the bottom of the longitudinal center line of the mounting base plate (3); After the test steel cable (1) passes around the test pulley (8) and the two auxiliary pulleys (13), the driving steel cable (11) passes around the driving pulley (12), and the driving steel cable (11) and the driving pulley (12) are fixedly connected at one point, and the two ends of the test steel cable (1) are connected to the corresponding two ends of the driving steel cable (11) through a tension regulator (10) to form a steel cable loop; The test bench for the fatigue life of a steel cable of an aircraft control system is used to adjust the pulley wrap angle of the test pulley (8) around the test steel cable (1) by adjusting the installation positions of two auxiliary pulleys (13) and a test pulley (8) on a mounting base plate (3), and to drive the test steel cable (1) to reciprocate around the test pulley (8) by driving a driving pulley (12) through a driving control system, so as to perform a fatigue life test on a steel cable test piece.

2. The test bench for fatigue life of steel cables of aircraft control systems according to claim 1, characterized in that: Also includes: Three pulley mounting bases, namely, a test pulley mounting base (5) and two auxiliary pulley mounting bases (6); The mounting base plate (3) is used to mount a test pulley (8) through a test pulley mounting base (5) that is slidably nested in the first hollow guide rail (2a), and to mount an auxiliary pulley (13) through an auxiliary pulley mounting base (6) that is slidably nested in each second hollow guide rail (2b); The distances between the center lines of the pulley grooves of the test pulley (8), the two auxiliary pulleys (13) and the driving pulley (12) and the mounting base plate (3) are the same.

3. The test bench for fatigue life of steel cables of aircraft control systems according to claim 2, characterized in that: Each pulley mounting base comprises: a manual adjustment knob (14), a screw rod (17) fixedly arranged at one end of the manual adjustment knob, after a bushing is inserted into the central bearing of the test pulley (8) or the auxiliary pulley (13), the test pulley (8) or the auxiliary pulley (13) together with the bushing is inserted onto the screw rod (17), and the distance between the test pulley (8) or the auxiliary pulley (13) and the mounting base plate (3) is adjusted by the screw rod (17), and the test pulley (8) or the auxiliary pulley (13) together with the bushing is fixed onto the screw rod (17) by two adjustment nuts (16) which are sleeved on the screw rod (17) and located on both sides of the pulley; Each pulley mounting base has a screw rod (17) passing through the second hollow guide rail (2b), and the screw rod (17) is located on both sides of the mounting base plate (3) and is screwed with flange nuts (15); after the three pulley mounting bases are slid and adjusted to the specified position, two flange nuts (15) are used to fix the base position to fix the longitudinal position of the test pulley (8) or the lateral position of the auxiliary pulley (13); The length of the bushing used is slightly greater than the bearing thickness of the test pulley (8) or the auxiliary pulley (13), so as to ensure that the test pulley (8) or the auxiliary pulley (13) can rotate freely after being fixed.

4. The test bench for fatigue life of steel cables of aircraft control systems according to claim 2, characterized in that: The driving control system comprises: a driving pulley (12), a driving steel cable (11), a stepping motor (18) and a motor encoding controller (22); The central axis of the driving pulley (12) is tightly sleeved on the output shaft (18a) of the stepping motor (18), and the driving pulley (12) is driven to rotate by the output shaft (18a) of the stepping motor (18). The position of the driving pulley (12) on the output shaft (18a) of the stepping motor (18) is fixed by two adjusting nuts (16) screwed on the output shaft (18a) and located on both sides of the driving pulley (12); the motor encoding controller (22) controls the stepping motor (18) to drive the driving pulley (12) to reciprocate through a preset program, so that the driving pulley (12) drives the test steel cable (1) to reciprocate through the driving steel cable (11) fixed thereon.

5. The test bench for fatigue life of steel cables of aircraft control systems according to claim 1, characterized in that: Each tension regulator (10) comprises: an adjustable tension screw sleeve (21), and steel cable connecting ends connected to both ends of the adjustable tension screw sleeve (21), and the steel cable connecting ends at both ends are respectively fixedly connected to one end of the driving steel cable (11) and the test steel cable (1), and the steel cable tension in the test steel cable loop is adjusted by adjusting the tightness of the tension screw sleeve (21).

6. The test bench for fatigue life of steel cables of aircraft control systems according to any one of claims 1 to 5, characterized in that: Also includes: A recording and display system; three wire displacement sensors (9), a counting sensor (19), a counting sensing magnet (20), and displays respectively connected to the three wire displacement sensors (9) and the counting sensor (19); Three wire displacement sensors (9) are fixedly mounted on the mounting base plate (3) and are correspondingly located at the ends of the three hollow guide rails. The wire ends of the wire displacement sensors (9) are connected to the screw rods (17) of the test pulley mounting base (5) or the auxiliary pulley mounting base (6) on the hollow guide rails on which they are mounted. The three wire displacement sensors (9) are used to measure the distance position information of the three pulley mounting bases and display it on a display; wherein the distance position information of the three pulley mounting bases is used to characterize the position distance information of the test pulley (8) and the two auxiliary pulleys; The counting sensor (19) is fixedly mounted on the mounting base plate (3) at the position where the driving pulley (12) is mounted, the counting induction magnet (20) is fixed on the side of the driving pulley (12) facing the mounting base plate, and the counting sensor (19) and the counting induction magnet (20) are arranged opposite to each other. The counting induction magnet (19) and the counting induction magnet (20) are used to record the number of reciprocating movements of the test steel rope (1) and display them on a display.

7. A test method for fatigue life of steel cables in aircraft control systems, characterized in that: A fatigue life test method is performed on a steel cable component to be tested using a test bench for fatigue life of a steel cable of an aircraft control system according to any one of claims 1 to 6, wherein the steel cable test piece to be tested comprises: a test steel cable (1) and a test pulley (8); the fatigue life test method comprises: Step 1, before the test, determine the test pulley (8), the test steel cable (1), the steel cable tension, the test pulley wrap angle and the steel cable movement frequency according to the test requirements; Step 2, installing a test pulley (8) and two auxiliary pulleys (13) on the mounting base plate (3) of the support frame, and adjusting the position distance between the test pulley (8) and the two auxiliary pulleys according to the wrap angle of the test pulley; Step 3, adjusting the installation distance between the test pulley (8) and the installation base plate (3) based on the distance between the center line of the pulley groove of the auxiliary pulley (13) and the installation base plate (3); Step 4, adjusting the tension of the steel cable, after the two ends of the test steel cable (1) are passed around the test pulley (8) and the two auxiliary pulleys (13), the two ends are connected to the corresponding two ends of the driving steel cable (11) through two tension adjusters (10), and then the adjustable tension screw sleeve (21) on the tension adjuster (10) is tightened until the tension of the steel cable reaches the tension value required by the test, thereby forming a test steel cable loop; Step 5, executing the fatigue test, inputting the cable movement frequency required by the test into the motor encoder controller (22), starting the stepper motor (18) to drive the entire cable loop to reciprocate according to a given program, and the test cable (1) performs reciprocating fatigue motion at the test pulley (8) according to the cable tension, pulley wrap angle and movement frequency required by the test, simulating the movement state on the aircraft, and completing the cycle counting of each movement through the counting sensor (19) and the counting induction magnet (20), and displaying the record on the display.

8. A test method for fatigue life of steel cables of aircraft control systems according to claim 7, characterized in that: The step 2 comprises: The positions of the test pulley mounting base (5) and the auxiliary pulley mounting base (6) are adjusted and fixed. First, the plane relative position coordinates of the test pulley (8) and the two auxiliary pulleys 6 are calculated and determined according to the pulley wrap angle, the diameter size of the test pulley (8) and the diameter size of the auxiliary pulley 6 specified in the test requirements. Then, the test pulley mounting base (5) and the two auxiliary pulley mounting bases (6) are slidably adjusted to the corresponding coordinate positions on the corresponding hollow guide rails. During the adjustment process, the distance values ​​are measured and observed through the pull-wire displacement sensor (9) and the display to ensure the accuracy of the coordinate positions of the three pulley mounting bases. Finally, the test pulley mounting base (5) and the two auxiliary pulley mounting bases (6) are fixed to the mounting base plate (3) through the flange nut (15).

9. A test method for fatigue life of steel cables of aircraft control systems according to claim 7, characterized in that: The step 3 comprises: Based on the distance between the center line of the pulley groove of the auxiliary pulley (13) and the mounting base plate (3), the distance between the end face of the test pulley (8) and the mounting base plate (3) is calculated according to the thickness of the test pulley (8) on the premise that the center line of the pulley groove of the test pulley (8) and the center line of the pulley groove of the driving pulley (12) coincide with each other. After the position of the test pulley (8) is installed and adjusted, the test pulley (8) is fixed together with the bushing to the corresponding position on the screw (17) in the test pulley mounting base (5) by two adjusting nuts (16).

10. A test method for fatigue life of steel cables of aircraft control systems according to claim 7, characterized in that: In the step 5, during the fatigue test, the test steel cable (1) is subjected to reciprocating motion by means of the test bench until the test steel cable (1) is damaged by wire or strand breakage, and the number of motion cycles recorded on the display is read as the life of the steel cable; or, based on the number of reciprocating motions of the steel cable given in the fatigue test, the test steel cable (1) is subjected to a corresponding number of reciprocating motions, and the condition of the test steel cable (1) is then detected.

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