Simple supported beam bending fatigue testing machine horizontal loading system

Abstract

The application discloses a simply supported beam bending fatigue testing machine horizontal loading system, which comprises a fixed loading end and a movable loading end, the center line of the movable loading end is in the same level with the center line of the fixed loading end; the fixed loading end is fixedly connected with a workbench surface, the overall structure comprises a first rotating shaft system composed of a first precision mechanical main shaft and a precision electric main shaft, and a first loading shaft system rotating along the axis of the first precision mechanical main shaft; the movable loading end is horizontally slidably connected with the workbench surface through a guide rail, the overall structure comprises a second rotating shaft system composed of a second precision mechanical main shaft, and a second loading shaft system rotating along the axis of the second precision mechanical main shaft; a sample to be tested is clamped between the fixed loading end and the movable loading end. The application makes the loading force and the gravity of the main shaft system perpendicular to each other, eliminates the influence of the gravity of the main shaft system on the loading force and the test result, overcomes the defects of the original vertical loading system, and makes the test result more accurate and reliable.

Description

TECHNICAL FIELD

[0001] The present application relates to a fatigue testing machine, in particular to a simply supported beam bending fatigue testing machine horizontal loading system. BACKGROUND

[0002] The simply supported beam bending fatigue testing machine is a device for testing the bending fatigue limit of materials. At present, the loading mode of the same testing machine at home generally adopts vertical loading, and the mechanical spindle is usually supported at both ends, and the equal force arm is vertically loaded by the weight. The advantages of this loading mode are simple structure and easy implementation. The disadvantages are that the gravity of the spindle system is in the same direction as the loading force, so the gravity of the spindle system greatly disturbs the test results. The test shows that the dispersion of the test results is large. With the continuous improvement of the bending fatigue test standards of materials in the market, the disadvantages of the original vertical loading mode are becoming more and more prominent. SUMMARY

[0003] The present application provides a simply supported beam bending fatigue testing machine horizontal loading system to overcome the disadvantages of the existing bending fatigue testing machine vertical loading system, so that the gravity of the spindle system is perpendicular to the direction of the loading force, and the disturbance of the gravity of the spindle system to the loading force is overcome, and the accuracy of the test results is improved.

[0004] In order to achieve the above-mentioned purpose, the present application provides the following technical scheme:

[0005] A simply supported beam bending fatigue testing machine horizontal loading system, comprising a fixed loading end and a movable loading end, the center line of the movable loading end is level with the center line of the fixed loading end; the fixed loading end is fixedly connected with the workbench surface, and the overall structure comprises a first rotating shaft system composed of a first precision mechanical spindle and a precision electric spindle, and a first loading shaft system rotating along the axis of the first precision mechanical spindle; the movable loading end is horizontally slidably connected with the workbench surface through a guide rail, and the overall structure comprises a second rotating shaft system composed of a second precision mechanical spindle, and a second loading shaft system rotating along the axis of the second precision mechanical spindle; the test sample is clamped between the fixed loading end and the movable loading end.

[0006] Further, the first rotating shaft system comprises a fixed frame, a first precision mechanical spindle, a flexible coupling and a precision electric spindle; the fixed frame is fixed on the workbench surface; the first precision mechanical spindle and the precision electric spindle are arranged in the horizontal direction and connected through the flexible coupling; the first precision mechanical spindle is installed in the fixed frame.

[0007] Further, the first loading shaft system comprises a frame body, an upper cover, half shafts and bearing boxes, the frame body and the upper cover form a bearing seat body; coaxial upper and lower shaft holes are respectively formed on the frame body and the upper cover for mounting and fixing two half shafts; two bearing boxes are coaxially mounted on the shell of the first precision mechanical spindle, the bearings built in the bearing boxes cooperate with the upper and lower half shafts, the horizontal position of the upper half shaft can be finely adjusted for adjusting the coaxiality of the upper and lower bearings.

[0008] Further, the first loading force arm rod is fixedly connected with the shell of the first precision mechanical spindle through the first loading shaft system for providing a loading torque with a fixed force arm length, the center line of the first loading force arm rod is parallel to the workbench surface and intersects and is perpendicular to the center line of the first precision mechanical spindle; the first supporting arm is fixed outside the fixed frame, the first loading force arm rod hangs loading weights through a fixed pulley on the first supporting arm through a steel wire rope, the fixed point of the first loading force arm rod and the contact point passing through the top of the fixed pulley are in the same height so that the steel wire rope between the two points keeps a horizontal state.

[0009] Further, the second rotating shaft system comprises a movable frame, a sliding block, a guide rail and a second precision mechanical spindle; the movable frame horizontally slides on the workbench surface through the sliding block and the guide rail; the second precision mechanical spindle is installed inside the movable frame.

[0010] Further, the second loading shaft system comprises a frame body, an upper cover, half shafts and bearing boxes, the frame body and the upper cover form a bearing seat body; coaxial upper and lower shaft holes are respectively formed on the frame body and the upper cover for mounting and fixing two half shafts; two bearing boxes are coaxially mounted on the shell of the second precision mechanical spindle, the bearings built in the bearing boxes cooperate with the upper and lower half shafts, the horizontal position of the upper half shaft can be finely adjusted for adjusting the coaxiality of the upper and lower bearings.

[0011] Further, the second loading force arm rod is fixedly connected with the shell of the second precision mechanical spindle through the second loading shaft system for providing a loading torque with a fixed force arm length; the center line of the second loading force arm rod is parallel to the workbench surface and intersects and is perpendicular to the center line of the second precision mechanical spindle; the second supporting arm is fixed outside the movable frame, the second loading force arm rod hangs loading weights through a fixed pulley on the second supporting arm through a steel wire rope, the fixed point of the second loading force arm rod and the contact point passing through the top of the fixed pulley are in the same height so that the steel wire rope between the two points keeps a horizontal state.

[0012] Further, the first precision mechanical spindle and the second precision mechanical spindle are both composed of a spindle, a shell, a front end cover, a rear end cover, a dust cover, a clamping nut, an ER chuck, a spacer ring, a spacer sleeve, a gasket, a front end bearing, a rear end bearing and a round nut; the front end bearing and the rear end bearing are arranged at both ends of the shell to form two supporting points of the shafting, and each adopts two sets of angular contact bearings back to back to form a bearing set; the spindle is installed in the shell, the front end cover and the rear end cover are positioned at both ends of the shell and are in labyrinth non-contact sealing with the spindle; the dust cover is arranged at the front end cover and is used for dust prevention at the front end of the spindle, and the sealing adopts a labyrinth non-contact sealing; the round nut is used for fixing the spindle and adjusting the axial clearance of the shafting; the ER chuck is installed at the front end of the spindle through the clamping nut; and the spacer sleeve, the spacer ring and the gasket are arranged between the shell and the spindle.

[0013] Compared with the prior art, the beneficial effects of the present application are:

[0014] The horizontal loading system of the simply supported beam bending fatigue testing machine of the present application makes the loading force and the gravity of the spindle system perpendicular to each other, eliminates the influence of the gravity of the spindle system on the loading force and the test results, overcomes the drawbacks of the original vertical loading system, and makes the test results more accurate and reliable. BRIEF DESCRIPTION OF DRAWINGS

[0015] Figure 1 It is a perspective view of the horizontal loading system of the simply supported beam bending fatigue testing machine of the present application.

[0016] Figure 2 It is a front view of the horizontal loading system of the simply supported beam bending fatigue testing machine of the present application.

[0017] Figure 3 It is a structure diagram of the fixed loading end of the present application.

[0018] Figure 4 It is a front view of the movable loading end of the present application.

[0019] Figure 5 It is a sectional view of the first loading shafting and the second loading shafting of the present application.

[0020] Figure 6 It is a sectional view of the first precision mechanical spindle and the second precision mechanical spindle of the present application.

[0021] BRIEF DESCRIPTION OF DRAWINGS:

[0022] 1, first precision mechanical spindle, 2, flexible coupling, 3, precision electric spindle, 4, fixed frame, 5, movable frame, 6, first loading arm rod, 7, first arm, 8, workbench, 9, loading weight, 10, test sample, 11, second precision mechanical spindle, 12, second loading arm rod, 13, second arm, 14, frame, 15, upper cover, 16, half shaft, 17, bearing box, 18, fixed pulley, 19, slider, 20, guide rail, 21, wire drag chain, 22, spindle, 23, shell, 24, front end cover, 25, rear end cover, 26, dust cover, 27, clamping nut, 28, ER chuck, 29, spacer ring, 30, spacer, 31, washer, 32, front end bearing, 33, rear end bearing, 34, round nut. DETAILED DESCRIPTION

[0023] In order to make the skilled in the art better understand the technical scheme of the present application, the present application will be further described in detail below with reference to the drawings and examples.

[0024] As Figures 1-6 shown, the simply supported beam bending fatigue testing machine horizontal loading system provided by the present application includes two parts of fixed loading end and movable loading end, two parts are respectively arranged with two same precision mechanical spindles, the center line of the movable loading end is level with the center line of the fixed loading end, and the two precision mechanical spindles are required to be strictly level with the center of the workbench 8, which is realized by assembly adjustment.

[0025] The fixed loading end is fixedly connected with the workbench 8, and the overall structure includes a first rotating shaft system composed of the first precision mechanical spindle 1 and the precision electric spindle 3, and a first loading shaft system rotating along the axis of the first precision mechanical spindle 1; the precision electric spindle 3 is required to be coaxial with the first precision mechanical spindle 1, which is realized by assembly adjustment to achieve flexible rotation.

[0026] The movable loading end is horizontally slidably connected with the workbench 8 through the guide rail 20, and the overall structure includes a second rotating shaft system composed of the second precision mechanical spindle 11, and a second loading shaft system rotating along the axis of the second precision mechanical spindle 11, the center height of the movable loading end remains unchanged during the whole movement process, which is realized by assembly adjustment.

[0027] The test sample 10 is clamped between the fixed loading end and the movable loading end.

[0028] Among them, as Figure 1 and Figure 2 shown:

[0029] The precision mechanical spindle includes the first precision mechanical spindle 1 and the second precision mechanical spindle 11, which is used to provide a stable rotating shaft system, requires high speed and low rotational inertia, can rotate around the axis of the spindle, and has small rotating friction torque.

[0030] Flexible coupling 2, used to transmit the rotational torque between the precision electric spindle 3 and the first precision mechanical spindle 1, requires flexible connection, can adapt to a certain different shaft degree, low rotational inertia.

[0031] Precision electric spindle 3, used to provide high-speed rotating power, requires high rotational speed, low rotational inertia, and large speed regulation range.

[0032] Fixed frame 4, used to support the driving end first precision mechanical spindle 1 and the precision electric spindle 3, with a first loading shaft structure rotating around the vertical direction (Z axis).

[0033] Movable frame 5, used to support the passive end second precision mechanical spindle 11, with a second loading shaft structure rotating around the vertical direction (Z axis), the movable frame can move freely along the horizontal transverse direction (X axis), and the friction force is small.

[0034] Loading arm rod, including first loading arm rod 6 and second loading arm rod 12, respectively connected with the first precision mechanical spindle 1 and the second precision mechanical spindle 11, providing a fixed arm length loading torque.

[0035] Support arm, including first support arm 7 and second support arm 13, respectively connected with the fixed frame and the movable frame, providing a fixed arm length reaction loading torque.

[0036] Workbench 8, used to support the installation of components such as fixed frame 4 and movable frame 5.

[0037] Loading weight 9, used to provide a loading torque, and a corresponding number of weights are hung according to different test requirements.

[0038] Tested sample 10, a simply supported beam part to be measured.

[0039] Specifically, the fixed loading end is as shown in Figure 3 .

[0040] The first rotating shaft system includes the fixed frame 4, the first precision mechanical spindle 1, the flexible coupling 2 and the precision electric spindle 3; the fixed frame 4 is fixed on the workbench; the first precision mechanical spindle 1 and the precision electric spindle 3 are arranged in the horizontal direction and connected through the flexible coupling 2; it is required that the first precision mechanical spindle 1 and the precision electric spindle 3 are installed and adjusted to ensure coaxiality, connected through the flexible coupling 2 to achieve small friction resistance and low rotational inertia; the first precision mechanical spindle 1 is installed inside the fixed frame.

[0041] The center line of the first loading shaft system intersects and is perpendicular to the center line of the first precision mechanical spindle 1, and is perpendicular to the workbench.

[0042] As shown in Figure 5As shown, the first loading shaft system includes a frame 14, an upper cover 15, half shafts 16 and bearing boxes 17, the frame 14 and the upper cover 15 constitute a bearing seat body; coaxial upper and lower shaft holes are respectively formed on the frame 14 and the upper cover 15 for mounting and fixing two half shafts 16; two bearing boxes are coaxially mounted on the shell of the first precision mechanical spindle 1, the bearings built in the bearing boxes cooperate with the upper and lower half shafts 16, the horizontal position of the upper half shaft can be finely adjusted for adjusting the coaxiality of the upper and lower bearings. The assembly of the loading shaft system ensures that the upper and lower half shafts are strictly coaxial and rotate flexibly, the center line of the loading shaft system is the center line of the upper and lower half shafts, and the center line is achieved by adjusting the adjusting screw on the upper cover 15.

[0043] The first loading arm rod 6 is fixedly connected with the shell of the first precision mechanical spindle 1 through the first loading shaft system for providing a fixed length of loading arm for providing a fixed length of loading arm, the center line of the first loading arm rod 6 is parallel to the workbench surface, intersects and is perpendicular to the center line of the first precision mechanical spindle 1; the first loading arm rod 6 is hung with the loading weight 9 through the fixed pulley 18 on the first supporting arm 7 through the steel wire rope, the steel wire rope is fixed at the end of the first loading arm rod 6, the fixed point to the center line of the first precision mechanical spindle 1 is a fixed value (set to 200mm in the embodiment of the present application), the steel wire rope at the fixed point of the first loading arm rod 6 is in the same height with the contact point around the top of the fixed pulley 18, so that the steel wire rope between the two points remains horizontal.

[0044] The Z-axis direction is the center line of the loading shaft system, that is, the center line of the upper and lower half shafts, the loading arm is fixedly connected with the shell of the precision mechanical spindle and is horizontally arranged, and the loading horizontal direction load can make the precision mechanical spindle rotate along the Z-axis to generate a loading torque.

[0045] The movable loading end is as shown in Figure 4 .

[0046] The second rotating shaft system includes a movable frame 5, a sliding block 19, a guide rail 20, a wire drag chain 21 and a second precision mechanical spindle 11; the movable frame slides horizontally on the workbench surface through the sliding block and the guide rail; the second precision mechanical spindle 11 is installed inside the movable frame 5.

[0047] The center line of the second loading shaft system intersects perpendicularly with the center line of the second precision mechanical spindle 11 and is perpendicular to the workbench surface 8, as shown in Figure 5As shown, the second loading shafting is same as the first loading shafting, including the frame body 14, the upper cover 15, the half shaft 16 and the bearing box 17, the frame body 14 and the upper cover 15 constitute a bearing seat body; the frame body 14 and the upper cover 15 are respectively formed with coaxial upper and lower two shaft holes for installing and fixing two half shafts 16; two bearing boxes 17 are coaxially installed on the shell of the second precision machine main shaft 11, the bearing in the bearing box is matched with the upper and lower two half shafts, the horizontal position of the upper half shaft can be finely adjusted for adjusting the coaxiality of the upper and lower bearings. The assembly of the loading shafting ensures that the upper and lower two half shafts are strictly coaxial, rotating flexibly, which is realized by adjusting the adjusting screw on the upper end cover.

[0048] The second loading arm rod 12 is fixedly connected with the shell of the second precision machine main shaft 11 through the second loading shafting for providing a fixed length of loading arm length; the center line of the second loading arm rod 12 is parallel to the workbench surface 8 and intersects and is perpendicular to the center line of the second precision machine main shaft 11; the second arm 13 is fixed outside the movable frame 5, the second loading arm rod 12 hangs the loading weight through the fixed pulley 18 on the second arm 13 through a steel wire rope, the steel wire rope is fixed at the end of the second loading arm rod 12, the fixed point to the center line of the second precision machine main shaft 11 is a fixed value (set to 200mm in the embodiment of the present application), the steel wire rope at the fixed point of the second loading arm rod 12 and the contact point around the top of the fixed pulley is in the same height, so that the steel wire rope between the two points remains in a horizontal state.

[0049] As shown in the figure, Figure 6 As shown, the first precision machine main shaft 1 and the second precision machine main shaft 11 are both composed of a main shaft 22, a shell 23, a front end cover 24, a rear end cover 25, a dust cover 26, a clamping nut 27, an ER chuck 28, a spacer ring 29, a spacer sleeve 30, a gasket 31, a front end bearing 32, a rear end bearing 33 and a round nut 34; the front end bearing 32 and the rear end bearing 33 are arranged at both ends of the shell 23 to form two support points of the shafting, each of which adopts two sets of angular contact bearings back to back to form a bearing set; the main shaft 22 is installed in the shell 23, the front end cover 24 and the rear end cover 25 are positioned at both ends of the shell 23 and adopt a labyrinth non-contact seal with the main shaft 22; the dust cover 26 is arranged at the front end cover 24 for dustproof of the front end of the main shaft 22, the seal adopts a labyrinth non-contact seal; the round nut 34 is used for fixing the main shaft 22 and adjusting the axial clearance of the shafting. The ER chuck 28 is installed at the front end of the main shaft 22 through the clamping nut 27. The spacer sleeve 30, the spacer ring 29 and the gasket 31 are arranged between the shell 23 and the main shaft 22.

[0050] After the above adjustment is completed, the loading test can be carried out, the appropriate ER chuck is selected according to the size of the sample and connected with the precision machine main shaft, the loading is carried out from low speed to high speed and small load to large load, and the test procedure is entered.

[0051] The above examples are only used to illustrate the technical solutions of the present application, and are not intended to limit the present application; although the present application has been described in detail with reference to the foregoing examples, those skilled in the art should understand that the technical solutions recorded in the foregoing examples can be modified, or some technical features can be replaced by equivalent features, but these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A simply supported beam bending fatigue testing machine horizontal loading system characterized by, The device comprises a fixed loading end and a movable loading end, the center line of the movable loading end is level with the center line of the fixed loading end; the fixed loading end is fixedly connected with the workbench, and the overall structure comprises a first rotating shaft system composed of a first precision mechanical spindle and a precision electric spindle, and a first loading shaft system rotating along the axis of the first precision mechanical spindle; the movable loading end is horizontally slidably connected with the workbench through a guide rail, and the overall structure comprises a second rotating shaft system composed of a second precision mechanical spindle, and a second loading shaft system rotating along the axis of the second precision mechanical spindle; the tested sample is clamped between the fixed loading end and the movable loading end; The first rotating shaft system comprises a fixed frame, a first precision mechanical spindle, a flexible coupling and a precision electric spindle; the fixed frame is fixed on the workbench; the first precision mechanical spindle and the precision electric spindle are arranged horizontally and connected through the flexible coupling; the first precision mechanical spindle is installed in the fixed frame; The first loading arm rod is fixedly connected with the shell of the first precision mechanical spindle through the first loading shaft system, and is used for providing a fixed arm length loading torque; the center line of the first loading arm rod is parallel to the workbench, intersects and is perpendicular to the center line of the first precision mechanical spindle; the first loading arm rod is hung with a loading weight through a fixed pulley on a first supporting arm through a steel wire rope, and the fixed point of the steel wire rope on the first loading arm rod is level with the contact point around the top of the fixed pulley, so that the steel wire rope between the two points is kept in a horizontal state; The second rotating shaft system comprises a movable frame, a sliding block, a guide rail and a second precision mechanical spindle; the movable frame is horizontally slidably arranged on the workbench through the sliding block and the guide rail; the second precision mechanical spindle is installed in the movable frame; The second loading arm rod is fixedly connected with the shell of the second precision mechanical spindle through the second loading shaft system, and is used for providing a fixed arm length loading torque; the center line of the second loading arm rod is parallel to the workbench, intersects and is perpendicular to the center line of the second precision mechanical spindle; the second loading arm rod is hung with a loading weight through a fixed pulley on a second supporting arm through a steel wire rope, and the fixed point of the steel wire rope on the second loading arm rod is level with the contact point around the top of the fixed pulley, so that the steel wire rope between the two points is kept in a horizontal state.

2. The simply supported beam bending fatigue test machine horizontal loading system of claim 1, wherein, The first loading shaft system comprises a frame body, an upper cover, a half shaft and a bearing box, and the frame body and the upper cover constitute a bearing seat body; coaxial upper and lower shaft holes are formed on the frame body and the upper cover respectively, and are used for mounting and fixing two half shafts; two bearing boxes are coaxially mounted on the shell of the first precision mechanical spindle, bearings in the bearing boxes are matched with the upper and lower half shafts, and the horizontal position of the upper half shaft can be finely adjusted, so as to adjust the coaxiality of the upper and lower bearings.

3. The simply supported beam bending fatigue test machine horizontal loading system of claim 1, wherein, The second loading shaft system comprises a frame body, an upper cover, a half shaft and a bearing box, and the frame body and the upper cover constitute a bearing seat body; coaxial upper and lower shaft holes are formed on the frame body and the upper cover respectively, and are used for mounting and fixing two half shafts; two bearing boxes are coaxially mounted on the shell of the second precision mechanical spindle, bearings in the bearing boxes are matched with the upper and lower half shafts, and the horizontal position of the upper half shaft can be finely adjusted, so as to adjust the coaxiality of the upper and lower bearings.

4. The simply supported beam bending fatigue test machine horizontal loading system of claim 1, wherein, The first precision machine spindle and the second precision machine spindle are both composed of a spindle, a shell, a front end cover, a rear end cover, a dust cover, a clamping nut, an ER chuck, a spacer ring, a spacer sleeve, a gasket, a front end bearing, a rear end bearing and a round nut; the front end bearing and the rear end bearing are arranged at both ends of the shell to form two supporting points of the shafting, each of which adopts two sets of angular contact bearings back to back to form a bearing set; the spindle is installed in the shell, the front end cover and the rear end cover are positioned at both ends of the shell and are in labyrinth non-contact sealing with the spindle; the dust cover is arranged at the front end cover and is used for dust prevention at the front end of the spindle, and the sealing is in labyrinth non-contact sealing; the round nut is used for fixing the spindle and adjusting the axial clearance of the shafting; the ER chuck is installed at the front end of the spindle through the clamping nut; the spacer sleeve, the spacer ring and the gasket are arranged between the shell and the spindle.

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