CN210664982U - Wall surface deformation mechanism for resistance test - Google Patents
Wall surface deformation mechanism for resistance test Download PDFInfo
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- CN210664982U CN210664982U CN201922012335.6U CN201922012335U CN210664982U CN 210664982 U CN210664982 U CN 210664982U CN 201922012335 U CN201922012335 U CN 201922012335U CN 210664982 U CN210664982 U CN 210664982U
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- resistance test
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- 229920006335 epoxy glue Polymers 0.000 claims description 3
- 239000012948 isocyanate Substances 0.000 claims description 3
- 150000002513 isocyanates Chemical class 0.000 claims description 3
- 229910001220 stainless steel Inorganic materials 0.000 claims description 3
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- 238000000034 method Methods 0.000 description 3
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Abstract
The utility model discloses a warp wall mechanism that can be used to resistance test relates to resistance test technical field. The utility model discloses pass through the eccentric disc cam that a set of adjacent phase difference is 90 degrees on the plum blossom type shaft coupling drives the camshaft by step motor and rotate, thereby the rotation of eccentric disc cam makes the cam roller who links to each other rather than being reciprocating motion on the vertical direction, thereby make the elastic element compression make the motion of threaded rod pass to the wall that warp, because 5 eccentric disc cam phases differ, make the wall that warp that links to each other with first backup pad and second backup pad take place different motions at the same time, warp the wall and can export sinusoidal waveform. The utility model discloses a mechanism has easy operation, efficient, advantage with low costs, and can realize the sinusoidal motion of standard.
Description
Technical Field
The utility model relates to a resistance test technical field, concretely relates to warp wall mechanism that can be used to resistance test.
Background
Turbulent flow is a common flow form in fluid mechanics, viscous friction is commonly existed on the interface of different fluids, and viscous force on the solid-liquid interface is an important factor for forming the turbulent flow. With the continuous development of the current technological level, the performances of ships and underwater vehicles are increasingly perfect, and the number of the ships and underwater vehicles is also increasing. Therefore, how to effectively reduce the surface friction resistance of ships, underwater vehicles and the like becomes a breakthrough for creating new energy-saving technologies. Marine organisms such as raja can exert the drag reduction performance by utilizing the body functions and the self structure of the marine organisms, so that the marine organisms can swim rapidly underwater with extremely low resistance, and the bodies of the marine organisms are not attached by other marine organisms and microorganisms. This low energy, high efficiency swimming mode is desirable for any underwater vehicle to be able to. The development of bionic and wall drag reduction technologies requires us to understand and master physiological structures and internal motion mechanisms of fish, and realize low-resistance swimming to control the high efficiency of external flow. However, the methods such as numerical simulation and fluid experiment have the defect of long period, and are difficult to realize approximate simulation of the flow field of the actual marine environment, and many researches only stay at the theoretical level, so that the existing hydrodynamic drag reduction technology does not move to the engineering field.
SUMMERY OF THE UTILITY MODEL
In view of the problems existing in the prior art, the present invention provides a deformable wall mechanism for resistance testing, which has the advantages of simple operation, high efficiency, convenient disassembly, and capability of realizing standard sine movement.
The utility model provides a can be used to resistance test's deformation wall mechanism, includes the motor, the motor right-hand member is equipped with a pair of bearing support, its characterized in that: the bearing support is provided with a cam structure, the cam structure comprises a cam shaft, the cam shaft is provided with a group of eccentric disc cams with the adjacent phase difference of 90 degrees so as to output sine waveforms, a group of cam rollers are arranged in a way of being matched with the group of eccentric disc cams to do reciprocating motion in the vertical direction, each cam roller is fixed on a cam roller frame, each cam roller frame is provided with an elastic element upper foot pad and an elastic element lower foot pad, each cam roller frame is connected with the elastic element lower foot pad, an elastic element is arranged between the elastic element upper foot pad and the elastic element lower foot pad, a threaded rod is arranged on each elastic element upper foot pad, one end of each threaded rod is connected with the elastic element upper foot pad through a threaded pipe, the other end of the group of threaded rods is provided with a deformation wall surface, and the deformation wall surface is connected with the other end of the, the deformable wall surface comprises two wall surfaces, the joint of the two wall surfaces is fixed on the second support plate in the center, two ends of the deformable wall surface are set as movable ends, and the second support plates corresponding to the two movable ends are fixed with the deformable wall surface through the first support plate.
The wall surface deformation mechanism for resistance testing is characterized in that: the eccentric disc cam is 5 eccentric disc cams, and the cam roller is 5 cam rollers, and the threaded rod is 5 threaded rods, the threaded rod is the telescopic threaded rod.
The wall surface deformation mechanism for resistance testing is characterized in that: the second backup pad is 5 second backup pads, all is equipped with deep groove ball bearing in every second backup pad, and the wall that warp links to each other with 5 threaded rods through the deep groove ball bearing in 5 second backup pads, ensures the controllability of threaded rod height.
The wall surface deformation mechanism for resistance testing is characterized in that: the wall that warp is the rectangle wall, adopts and presss from both sides stainless steel meshwork offset plate, the junction of two walls passes through epoxy glue and arranges additive isocyanate and fixes in the second backup pad of positive center, the second backup pad that two expansion ends correspond passes through first backup pad joint at two expansion ends.
The wall surface deformation mechanism for resistance testing is characterized in that: each cam roller is the same as each eccentric disc cam in thickness, a threaded hole is formed in each cam roller, the cam rollers are connected with the cam roller frame through hexagon bolts, relative sliding or deformation is avoided, the cam rollers are just clamped below each cam roller frame, and the cam rollers are prevented from rolling relatively.
The wall surface deformation mechanism for resistance testing is characterized in that: elastic element is cylindrical spring, every elastic element goes up the callus on the sole and passes through hexagon head bolt and screwed pipe connection, and every elastic element is lower the callus on the sole and is passed through hexagon head bolt and roller frame and link to each other for the unbalanced length that the stroke difference brought about the eccentric disc cam of compensation, the screwed pipe is provided with the internal thread, be used for with the external screw thread fit of threaded rod one end in order to change the amplitude of waveform output, realize the change of screw rod length, thereby change the curvilinear amplitude of waveform, the diversified sine wave form of being convenient for is exported.
The wall surface deformation mechanism for resistance testing is characterized in that: the bearing support comprises an upper bearing support and a lower bearing support, a waterproof deep groove ball bearing is arranged in the bearing support, the upper bearing support is fixed with the lower bearing support through a cylindrical hexagon head bolt, one end of the camshaft penetrates through the waterproof deep groove ball bearing and the end cover and is connected with the motor through a quincunx coupler, and the other end of the camshaft is sealed in a sealed end cover of the bearing support.
The wall surface deformation mechanism for resistance testing is characterized in that: the eccentric disc cam is used as a driving link and is connected with the cam roller, the sine waveform is set to have two curve stages of pushing and two return strokes, the two curve stages can be assembled from two ends to the center, a group of eccentric disc cams are arranged on the cam shaft according to a phase difference of 90 degrees, the eccentric disc cams are fixed in the circumferential direction by the sleeves and simultaneously transmit torque, the eccentric disc cams are fixed in the radial direction by common flat keys, and when the motor moves, the cam shaft is driven to move and the eccentric disc cams fixed on the cam shaft rotate, so that the circular reciprocating motion of the cam roller is realized.
The wall surface deformation mechanism for resistance testing is characterized in that: the motor is fixed on the base through a hexagon head bolt, the motor is a stepping motor, and the pair of bearing supports are fixed on the left side and the right side of the base respectively through the hexagon head bolt.
The utility model has the advantages that:
1) by the device of the utility model, the occupied space of the laboratory hydrodynamic experiment device can be reduced, the standard sinusoidal motion can be realized, the period and the amplitude can be effectively adjusted, and the experimental diversity is increased;
2) the utility model discloses whole device interchangeability is strong, and is with low costs, has reduced the trouble that the repair brought simultaneously, has improved the efficiency that the researcher carries out hydrodynamic test.
3) Through the utility model discloses, for the researcher who is dedicated to the development of drag reduction technique provides the reliable and accurate technological parameter of experiment on numerical simulation's basis, promote drag reduction technique to further development.
Drawings
Fig. 1 is a schematic structural view of the present invention;
FIG. 2 is a schematic structural view of a camshaft and a cam according to the present invention;
FIG. 3 is a schematic view of the bearing seat structure of the supporting structure of the present invention;
fig. 4 is a schematic view of the roller structure and the telescopic threaded rod structure of the present invention;
fig. 5 is a schematic view of the structure of the supporting plate and the deformed wall surface of the present invention.
In the figure: 101-a stepper motor; 102-plum blossom type coupling; 103-an upper bearing support; 104-lower bearing support; 105-an eccentric disc cam; 106-a camshaft; 107-waterproof deep groove ball bearing; 108-hexagon head bolt; 109-a closed end cap; 201-cam roller; 202-roller frame; 301-elastic element lower foot pad; 302-a resilient element; 303-a foot pad on the elastic element; 304-a threaded pipe; 305-a threaded rod; 401 — deformed wall; 402-a first support plate; 403-deep groove ball bearing; 404-second support plate.
Detailed Description
The invention will be further described with reference to the accompanying drawings, but the scope of protection of the invention is not limited to the scope described.
As shown in fig. 1-5, a deformable wall mechanism for resistance test, comprising a motor 101, the motor 101 of the present invention is a step motor, the right end of the motor 101 is provided with a pair of bearing supports, the bearing supports are provided with a cam shaft 106, the bearing supports comprise an upper bearing support 103 and a lower bearing support 104, a waterproof deep groove ball bearing 107 is provided therein, the upper bearing support 103 is fixed with the lower bearing support 104 through a cylindrical hexagon head bolt 108, one end of the cam shaft 106 passes through the waterproof deep groove ball bearing 107 and the end cap is connected with the motor 101 through a quincunx coupling 102 to realize coaxial rotation with the motor 101, the other end of the cam shaft 106 is sealed in a sealed end cap 109 of the bearing support, the cam shaft 106 is provided with a set of eccentric disc cams 105 with adjacent phase difference of 90 degrees so as to output sinusoidal waveforms, the eccentric disc cams 105 can be assembled from both ends to the center, the set of eccentric disc cams 105 is installed, circumference adopts the fixed moment of torsion that transmits simultaneously of sleeve, and is radial fixed with ordinary parallel key, the utility model discloses well eccentric disc cam is 5 eccentric disc cams, cooperates every eccentric disc cam 105 to make reciprocating motion in the vertical direction and is equipped with a set of cam roller 201, the utility model discloses cam roller 201 is 5, uses cam roller 201 to increase sliding friction's area of contact, improves driven precision simultaneously. Each cam roller 201 has the same thickness as the eccentric disc cam 105, and is provided with a threaded hole, and is connected with the cam roller frame 202 through a hexagon head bolt 108, so as to ensure that relative sliding or deformation does not occur, the cam roller 201 is just clamped below the cam roller frame 202, so as to ensure that the cam roller 201 does not roll relatively, each cam roller frame 202 is provided with an elastic element upper foot pad 303 and an elastic element lower foot pad 301, an elastic element 302 is arranged between the elastic element upper foot pad 303 and the elastic element lower foot pad 301, the elastic element 302 of the utility model is a cylindrical spring, each elastic element lower foot pad 301 is fixed on the cam roller frame 202 through the hexagon head bolt 108, each elastic element upper foot pad 303 is provided with a threaded rod 305, the utility model discloses 5 threaded rods 305, the utility model discloses a threaded rod 305 is a retractable threaded rod, each threaded rod 305 is connected with the elastic element upper foot pad 303 through the threaded pipe 304, the foot pads 303 on each elastic element are connected with a threaded pipe 304 through hexagonal bolts 108 and used for compensating unbalanced length caused by the difference of the upper stroke and the lower stroke of the eccentric disc cam 105, internal threads are arranged in the threaded pipe 304 and used for being matched with external threads at one end of a threaded rod 305 to change the amplitude of waveform output, the period of the output waveform is controlled by the frequency of the motor 101, and different sine waveform tests can be realized. The length of the threaded rod 305 is changed, so that the phase difference is changed, diversified sine wave output is facilitated, the other end of the set of threaded rod 305 is provided with a deformation wall surface 401, the deformation wall surface 401 is fixed through a deep groove ball bearing 403 of the threaded rod 305, and the sliding accuracy can be achieved. The wall 401 that warp is the rectangle wall, including two walls, two terminal surfaces are established to the expansion end, the junction of two walls passes through epoxy glue collocation additive isocyanate to be fixed on the second backup pad 404 in positive center, the second backup pad 404 that two expansion ends correspond is through first backup pad 402 joint at two expansion ends, the wall surpasss the length change that warp wall 401 when first backup pad 402, prevent to warp wall 401 and is stretched into freely in the backup pad that has the draw-in groove by the stretch-off or the flat other end that collapses, with the deformation difference that brings when guaranteeing the motion deformation. The deformed wall 401 is made of a stainless steel mesh plywood, so that a certain breaking force and elongation can be kept, the elastic element 302 is in a free length when the deformed wall 401 is horizontal, and when the eccentric disc cam 105 moves, the elastic element 302 is compressed or stretched, and restoring force can drive the deformed wall 401 to restore to a horizontal shape.
The utility model discloses a can be used to deformation wall mechanism of resistance test, including the base, the base design is hollow, and motor 101 passes through hexagon head bolt 108 to be fixed on the base, and a pair of bearing passes through hexagon head bolt 108 to be fixed respectively in the base left and right sides.
At the beginning of the experiment, the motor 101 is started to drive the cam shaft 106 to rotate, and the eccentric disc cam 105 on the cam shaft 106 is guided to rotate. Rotation of the eccentric disc cam 105 causes the cam roller 201, which is closely attached thereto, to reciprocate in the vertical direction, causing the elastic member 302 to compress and thereby transmitting the movement of the threaded rod 305 to the deformed wall 401. Due to the phase difference between the 5 eccentric disc cams 105, the deformable wall 401 connected to the first support plate 402 moves differently at the same time, i.e. the output of the whole deformable wall 401 appears sinusoidal.
Claims (9)
1. The utility model provides a warp wall mechanism that can be used to resistance test, includes motor (101), motor (101) right-hand member is equipped with a pair of bearing support, its characterized in that: the bearing support is provided with a cam structure, the cam structure comprises a cam shaft (106), the cam shaft (106) is provided with a group of eccentric disc cams (105) with adjacent phase difference of 90 degrees, so as to output sine wave, the eccentric disc cams (105) are matched to do reciprocating motion in the vertical direction and provided with a group of cam rollers (201), each cam roller (201) is fixed on a cam roller frame (202), each cam roller frame (202) is provided with an elastic element upper foot pad (303) and an elastic element lower foot pad (301), each cam roller frame (202) is connected with the elastic element lower foot pad (301), an elastic element (302) is arranged between the elastic element upper foot pad (303) and the elastic element lower foot pad (301), a threaded rod (305) is arranged on each elastic element upper foot pad (303), one end of each cam roller (305) is connected with the elastic element upper foot pad (303) through a threaded pipe (304), the other end of the threaded rod (305) is provided with a deformation wall surface (401), the deformation wall surface (401) is connected with the other end of the threaded rod (305) through a group of second support plates (404), the deformation wall surface (401) comprises two wall surfaces, the joint of the two wall surfaces is fixed on the second support plate (404) in the center of the center, the two ends of the deformation wall surface (401) are set as movable ends, and the second support plates (404) corresponding to the two movable ends are fixed with the deformation wall surface (401) through the first support plates (402).
2. A deformed wall structure for a resistance test according to claim 1, wherein: the eccentric disc cam (105) is 5 eccentric disc cams, the cam rollers (201) are 5 cam rollers, the threaded rod (305) is 5 threaded rods, and the threaded rod (305) is a telescopic threaded rod.
3. A deformed wall structure for a resistance test according to claim 1, wherein: the second support plates (404) are 5, each second support plate (404) is provided with a deep groove ball bearing (403), and the deformation wall surface (401) is connected with 5 threaded rods (305) through the deep groove ball bearings (403) on the 5 second support plates (404), so that the height adjustability of the threaded rods (305) is ensured.
4. A deformed wall structure for a resistance test according to claim 3, wherein: the wall face (401) warp is the rectangle wall face, adopts and presss from both sides stainless steel meshwork offset plate, the junction of two wall faces is fixed on second backup pad (404) at the positive center through epoxy glue collocation additive isocyanate, second backup pad (404) that two expansion ends correspond are through first backup pad (402) joint at two expansion ends.
5. A deformed wall structure for a resistance test according to claim 1, wherein: each cam roller (201) is the same as each eccentric disc cam (105) in thickness, a threaded hole is formed in each cam roller, the cam rollers are connected with the cam roller frame (202) through the hexagon head bolts (108), relative sliding or deformation is avoided, the cam rollers (201) are just clamped below each cam roller frame (202), and the cam rollers (201) are prevented from rolling relatively.
6. A deformed wall structure for a resistance test according to claim 1, wherein: elastic element (302) are cylindrical spring, callus on the sole (303) are connected with screwed pipe (304) through hexagon head bolt (108) on every elastic element, callus on the sole (301) link to each other with roller frame (202) through hexagon head bolt (108) under every elastic element for the unbalanced length that the difference of the upper and lower stroke of compensation eccentric disc cam (105) brought, be provided with the internal thread in screwed pipe (304), be used for with the external screw thread cooperation of threaded rod (305) one end in order to change the amplitude of waveform output, realize the change of threaded rod (305) length, thereby change the amplitude of wave form curve, be convenient for diversified sine wave form output.
7. A deformed wall structure for a resistance test according to claim 1, wherein: the bearing support comprises an upper bearing support (103) and a lower bearing support (104), a waterproof deep groove ball bearing (107) is arranged in the bearing support, the upper bearing support (103) is fixed with the lower bearing support (104) through a cylindrical hexagon head bolt (108), one end of a cam shaft (106) penetrates through the waterproof deep groove ball bearing (107) and an end cover to be connected with a motor (101) through a quincunx coupler (102), and the other end of the cam shaft (106) is sealed in a sealed end cover (109) of the bearing support.
8. A deformed wall structure for a resistance test according to claim 1, wherein: the eccentric disc cam (105) is used as a driving element and connected with the cam roller (201), a sine wave shape is set to have two curve stages of pushing stroke and two return strokes and can be assembled from two ends to the center, a group of eccentric disc cams (105) are arranged on the cam shaft (106) according to a phase difference of 90 degrees, the circumferential direction adopts sleeve fixation and simultaneously transmits torque, the radial direction is fixed by a common flat key, and when the motor (101) moves, the cam shaft (106) is driven to move and the eccentric disc cam (105) fixed on the cam shaft (106) rotates, so that the circular reciprocating motion of the cam roller (201) is realized.
9. A deformed wall structure for a resistance test according to claim 1, wherein: the base is designed to be a hollow base, the motor (101) is fixed to the base through the hexagon head bolts (108), the motor (101) is a stepping motor, and the pair of bearing supports are fixed to the left side and the right side of the base through the hexagon head bolts (108) respectively.
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CN201922012335.6U CN210664982U (en) | 2019-11-20 | 2019-11-20 | Wall surface deformation mechanism for resistance test |
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CN201922012335.6U CN210664982U (en) | 2019-11-20 | 2019-11-20 | Wall surface deformation mechanism for resistance test |
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Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
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CN110864872A (en) * | 2019-11-20 | 2020-03-06 | 浙江工业大学 | Wall surface deformation mechanism for resistance test |
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Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
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CN110864872A (en) * | 2019-11-20 | 2020-03-06 | 浙江工业大学 | Wall surface deformation mechanism for resistance test |
CN110864872B (en) * | 2019-11-20 | 2024-05-28 | 浙江工业大学 | Deformation wall surface mechanism capable of being used for resistance test |
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