Crank rocker mechanism with swing angle amplifying device

Abstract

The utility model belongs to the technical field of steel wire rope bending fatigue testing, and particularly relates to a crank rocker mechanism with a swing angle amplifying device, which comprises a motor, a coupler, a speed reducer, a crank, a connecting rod, a rocker and a rocker shaft. The device is characterized in that the shaft end of the rocker is further connected with a sector gear through a key, the sector gear is meshed with a circular gear arranged at the shaft end of a pulley, one end or two ends of the pulley shaft are connected with a driving pulley, and the pulley shaft is connected with a pulley support through two bearing seats. The utility model has the advantages that: 1) the purpose of increasing the swing angle of the reciprocating motion of the pulley is achieved, and the technical bottleneck that the bending fatigue test of the large-diameter steel wire rope cannot be realized because the required test stroke is too large is solved; 2) the structure can also be used in other occasions where the swing angle amplitude needs to be increased or the swing stroke of the swing mechanism needs to be increased;

Description

Technical Field

[0001] The utility model belongs to the technical field of steel wire rope bending fatigue testing, in particular to a crank rocker mechanism with a swing angle amplification device. Background Art

[0002] In the field of wire rope bending fatigue testing research, the bending fatigue characteristics of wire ropes have become a key indicator for evaluating the overall performance of wire ropes. Specific evaluation methods include double-pulley reciprocating bending fatigue and S-bend reciprocating bending fatigue testing. The purpose of the test is to allow the wire rope to move on a pulley of matching diameter for a distance greater than the circumference corresponding to a 180° wrap angle, in order to examine the bending fatigue life of the wire rope. Usually, the pulley diameter D is about 20-25 times the wire rope diameter d, and the wire rope movement distance is not less than πD / 2. Figure 1 , is a schematic diagram of the principle of the bending fatigue test of the double pulley of the wire rope. For the small diameter wire rope, the reciprocating swing of the double pulley can be achieved by adopting the crank connecting rod mechanism, and this movement distance is relatively easy to achieve. Figure 2 The figure is a schematic diagram of the principle of the S-bend bending fatigue test of a steel wire rope. It can be seen that the structure of the S-bend bending fatigue test device is more complicated. The steel wire rope (21) to be tested is wound onto the test pulley (22). The ends of the steel wire rope are fixed to the driving pulley (24) by means of pressure blocks (23). After the steel wire rope is fixed, the tensioning hydraulic cylinder (25) is started and the steel wire rope is tensioned at a constant tension according to the preset tension value of the test. At this time, the driving wheel is started and the driving wheel is made to swing back and forth according to the required swing angle through the power mechanism. At this time, the test section of the steel wire rope is bent back and forth on the tensioning pulley or the S-bend pulley to perform the bending fatigue test.

[0003] Chinese utility model patent application number 201721460028.9 discloses a structure for bending fatigue testing of torsion-resistant steel wire ropes. The structure includes a power pulley, a first drive device that rotates the power pulley, a driven pulley, a second drive device that moves the driven pulley along the line connecting the center points of the power and driven pulleys, and a pulley assembly disposed between the power and driven pulleys to form a wrap angle. This solution is suitable for bending fatigue testing of torsion-resistant steel wire ropes.

[0004] For bending fatigue tests of steel wire ropes with a diameter of 60 mm or more, achieving a movement distance of not less than πD / 2 is a difficult technical challenge to achieve in existing technical solutions. The key to the problem lies in how to increase the movement swing angle of the pulley and thus increase the running stroke of the steel wire rope under the condition of a certain pulley diameter. This has become a breakthrough in solving this problem, but has not yet been mentioned in the literature. Utility Model Content

[0005] The purpose of the utility model is to provide a crank rocker mechanism with a swing angle amplification device, which overcomes the shortcomings of the existing technology. By adding a swing angle amplification device on the pulley shaft, the purpose of increasing the reciprocating swing angle of the active pulley is achieved. The speed ratio of the active pulley can be adjusted according to the amplitude of the swing angle, solving the technical bottleneck of the inability to implement bending fatigue testing of large-diameter steel wire ropes due to the excessively large required test stroke.

[0006] To achieve the above objectives, the present invention is implemented through the following technical solutions:

[0007] A crank-rocker mechanism with a swing angle amplification device comprises a motor, a coupling, a reducer, a crank, a connecting rod, a rocker and a rocker shaft. The motor is connected to the reducer via a coupling, the output shaft end of the reducer is connected to the crank, the end of the crank is hinged to one end of the connecting rod, the other end of the connecting rod is hinged to the end of the rocker, and the rocker is connected to the rocker shaft via a key. The invention is characterized in that the rocker shaft end is also connected to a sector gear via a key, the sector gear is meshed with a circular gear provided at the pulley shaft end, one end or both ends of the pulley shaft are connected to an active pulley, and the pulley shaft is connected to the pulley bracket via two bearing seats.

[0008] Furthermore, the output shaft of the reducer is in the form of a hollow shaft, the crank is connected to the output shaft hole through the crank shaft, and the crank shaft and the output shaft are connected through a flat key, a double key or a spline.

[0009] Furthermore, the gear ratio between the sector gear and the circular gear is 2-3:1.

[0010] Furthermore, both ends of the rocker shaft are respectively connected to bearing seats, and the bearing seats are arranged on the pulley bracket.

[0011] Furthermore, the connecting rod and the rocker are connected via a joint bearing.

[0012] Furthermore, the pulley bracket is a combined structure of upper and lower parts.

[0013] Furthermore, a rope clamp for fixing the steel wire rope is provided on the rim of the active pulley.

[0014] Compared with the prior art, the beneficial effects of the present invention are:

[0015] 1) By adding a swing angle amplification device to the pulley shaft, the purpose of increasing the reciprocating swing angle of the pulley is achieved. The speed ratio of the pulley can be adjusted according to the amplitude of the swing angle, solving the technical bottleneck that large-diameter wire ropes cannot be subjected to bending fatigue testing due to the required test stroke being too large.

[0016] 2) The structure of the utility model can also be used in other fields of mechanical equipment where the swing angle amplitude needs to be increased or the swing mechanism needs to increase the swing stroke. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a schematic diagram of the principle of the double pulley bending fatigue test of a wire rope in the prior art;

[0018] Figure 2 This is a schematic diagram of the principle of the S-bend fatigue test of a steel wire rope in the prior art;

[0019] Figure 3 This is a schematic diagram of the three-dimensional structure of an embodiment of the utility model;

[0020] Figure 4 This is a schematic diagram of the planar structure of an embodiment of the utility model, in which the active pulley is not shown;

[0021] Figure 5 This is the initial position of the swing angle amplification device in the embodiment of the utility model;

[0022] Figure 6 It is the end position of the swing angle amplification device in the embodiment of the utility model.

[0023] In the figure: 1-motor, 2-coupling, 3-reducer, 4-crank, 5-connecting rod, 6-rocker, 7-sector gear, 8-circular gear, 9-pulley shaft, 10-driving pulley, 11-bearing seat, 12-pulley bracket, 13-crank shaft, 14-rocker shaft, 15-spherical bearing, 16-rope clamp, 17-base box, 21-wire rope, 22-test pulley, 23-pressure block, 24-driving pulley, 25-tensioning hydraulic cylinder. DETAILED DESCRIPTION

[0024] The technical solutions of the present invention will be described clearly and completely below in conjunction with specific embodiments. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments.

[0025] In order to more clearly illustrate the specific implementation methods of the utility model or the technical solutions in the prior art, the specific embodiments required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the specific embodiments described below are some implementation methods of the utility model. For ordinary technicians in this field, other specific embodiments can be obtained based on these specific embodiments without paying creative work.

[0026] The components of the embodiments of the present invention generally described and shown in the specific embodiments herein can be arranged and designed in countless different configurations. Therefore, the following detailed description of the embodiments of the present invention provided in the specific embodiments is not intended to limit the scope of the claimed invention, but rather merely represents selected embodiments of the present invention.

[0027] See Figure 3-6, is a schematic structural diagram of an embodiment of a crank-rocker mechanism with a swing angle amplification device according to the present invention. It includes a motor 1, a coupling 2, a reducer 3, a crank 4, a connecting rod 5, a rocker 6, and a rocker shaft 14. The motor 1 is connected to the reducer 3 via the coupling 2. The output shaft end of the reducer 3 is connected to the crank 4. The end of the crank 4 is hinged to one end of the connecting rod 5, and the other end of the connecting rod 5 is hinged to the end of the rocker 6. The connecting rod 5 and rocker 6 are connected by a spherical bearing 15. The rocker 6 converts the continuous rotational motion of the motor 1 and reducer 3 into reciprocating swinging motion.

[0028] The rocker 6 is connected to the rocker shaft 14 through a key, and torque transmission is achieved through a flat key. The end of the rocker shaft 14 is also connected to a sector gear 7 through a key. The sector gear 7 is meshed with the circular gear 8 provided at the end of the pulley shaft 9 to form a pair of angle amplification gear sets, which can achieve the purpose of increasing the reciprocating swing angle of the driving pulley. There is no relative motion between the sector gear 7 and the rocker 6. By adjusting the speed ratio of the meshing gears, the swing angle amplitude of the pulley shaft is adjusted, thereby achieving the required motion stroke of the wire rope during the test.

[0029] The meshing speed ratio between the sector gear 7 and the circular gear 8 is 3:1. The meshing backlash of the circular gear 8 is reduced by improving the center distance accuracy between the input shaft and the output shaft and correcting the gear tooth profile to avoid severe impact during the reciprocating motion.

[0030] The other end of the pulley shaft 9 is connected to a driving pulley 10, and the two ends of the pulley shaft 9 are connected to a pulley bracket 12 through a bearing seat 11. One end or both ends of the pulley shaft 9 are connected to the driving pulley 10. A rope clamp 16 for fixing a wire rope is provided on the wheel rim of the driving pulley 10.

[0031] The output shaft of the reducer 3 is a hollow shaft, and the crank 4 is connected to the output shaft hole through the crank shaft 13. The crank shaft 4 and the output shaft can be connected by a flat key, a double key or a spline. The crank shaft 13 is connected to the base box 17 through two bearing seats.

[0032] Rocker shaft 14 is connected to bearing seats at both ends, which are mounted on pulley bracket 12. Pulley bracket 12 is a split upper and lower structure, making installation and commissioning easier. When rocker 6 reciprocates around rocker shaft 14, sector gear 7 rotates synchronously around rocker shaft 14, driving the pulley shaft containing circular gear 8 to reciprocate at multiples of the rocker shaft 14's swing angle. This achieves the purpose of amplifying the rotation angle and solves the technical bottleneck of bending fatigue testing of large-diameter wire ropes due to the excessive test stroke required.

[0033] Although the embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and variations may be made to these embodiments without departing from the principles and spirit of the present invention, and the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A crank-rocker mechanism with a swing angle amplification device, comprising a motor, a coupling, a reducer, a crank, a connecting rod, a rocker, and a rocker shaft. The motor is connected to the reducer via a coupling, the output shaft end of the reducer is connected to the crank, the end of the crank is hinged to one end of the connecting rod, the other end of the connecting rod is hinged to the end of the rocker, and the rocker is connected to the rocker shaft via a key. The rocker shaft end is also connected to a sector gear through a key, and the sector gear is engaged with a circular gear provided at the pulley shaft end. One end or both ends of the pulley shaft are connected to a driving pulley, and the pulley shaft is connected to the pulley bracket through two bearing seats.

2. A crank-rocker mechanism with a swing angle magnifying device according to claim 1, characterized in that: The output shaft of the reducer is in the form of a hollow shaft, the crank is connected to the output shaft hole through the crank shaft, and the crank shaft and the output shaft are connected through a flat key, a double key or a spline.

3. The crank-rocker mechanism with a swing angle magnifying device according to claim 1, characterized in that: The gear ratio between the sector gear and the circular gear is 2-3:

1.

4. The crank-rocker mechanism with a swing angle magnifying device according to claim 1, characterized in that: Both ends of the rocker shaft are connected to bearing seats respectively, and the bearing seats are arranged on the pulley bracket.

5. The crank-rocker mechanism with a swing angle magnifying device according to claim 1, characterized in that: The connecting rod and the rocker are connected via a joint bearing.

6. The crank-rocker mechanism with a swing angle magnifying device according to claim 4, characterized in that: The pulley bracket is a combined structure of upper and lower parts.

7. The crank-rocker mechanism with a swing angle magnifying device according to claim 1, characterized in that: A rope clamp for fixing the steel wire rope is provided on the wheel rim of the active pulley.

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