Miniature vane shear apparatus

Abstract

The utility model relates to the technical field of shear apparatuses, in particular to a miniature vane shear apparatus, which comprises a counter-force frame used for bearing counter-acting force of a driving device; the driving device is used for driving the measuring rod to penetrate into and be pulled out of the soil body and performing torsional shearing on the soil body; the penetration and torsion switching device is used for switching the connection state of the driving device and the measuring rod when the driving device performs penetration and pull-out operation and torsion shearing operation on the measuring rod; the detection device is used for detecting and collecting axial force and torque generated when the driving device drives the measuring rod to act; wherein the end part of the measuring rod is connected with a miniature cross plate head, and the height-diameter ratio of the miniature cross plate head is greater than or equal to 2. The miniature vane shear apparatus is large in measuring range and high in precision, the accuracy of measuring the vertical shear strength of a soil body can be improved, a device for controlling the vane head to rotate can be protected from being damaged by axial force, and the service life is prolonged.

Description

Technical Field

[0001] The utility model relates to the technical field of shearing instruments, in particular to a micro cross-plate shearing instrument. Background Art

[0002] The cross-plate shear test is usually used to determine the shear strength of saturated soft clay. During the test, the cross-plate head is first inserted into the soil, and then rotated at a uniform speed until the soil is sheared. By measuring the torque applied to the cross-plate, the shear strength of the soil can be calculated by the formula.

[0003] However, the traditional cross-plate shear instrument is only suitable for saturated soft clay because the torque that can be applied and measured is very small, and it cannot be used for experiments in hard soils. In order to meet the needs of a large range of experiments in hard soils, some miniature cross-plate shear instruments have been developed in recent years.

[0004] Since the height-diameter ratio of the cross plate head of the existing micro cross plate shear instrument is relatively small, when the micro cross plate shear instrument is inserted into the soil for torsion shear, the proportion of the torque borne on the shear cylinder formed to the total torque on the plate head is also small, and the vertical shear strength corresponding to the shear cylinder is the focus of attention during the test. Therefore, the test accuracy of the existing micro cross plate shear instrument is relatively low. In addition, during the penetration process of the existing micro cross plate shear instrument, the device that controls the rotation of the cross plate head will also be affected by the axial force. When the axial force is large, it will cause damage to the related devices. Therefore, the range of the existing micro cross plate shear instrument is also small. Utility Model Content

[0005] The utility model aims to provide a micro cross-plate shear instrument with a large measuring range and high precision, which can improve the accuracy of measuring the vertical shear strength of soil, and can also protect the device for controlling the rotation of the cross-plate head from damage by axial force, thereby extending the service life.

[0006] In order to achieve the above purpose, the utility model provides the following technical solutions:

[0007] The utility model provides a micro cross plate shearing instrument, comprising a reaction frame for bearing the reaction force of a driving device;

[0008] A driving device, used for driving the measuring rod to penetrate into and pull out of the soil and to perform torsion shear on the soil;

[0009] A penetration-torsion switching device is used to switch the connection state between the driving device and the measuring rod when the driving device performs penetration and extraction operations and torsion and shear operations on the measuring rod;

[0010] A detection device, used to detect and collect the axial force and torque generated when the driving device drives the measuring rod to move;

[0011] Wherein, the end of the measuring rod is connected with a micro cross plate head, and the height-to-diameter ratio of the micro cross plate head is greater than or equal to 2.

[0012] Furthermore, the driving device includes a jack and a worm gear reducer. The jack is arranged on the top of the reaction frame, the worm gear reducer is arranged below the jack and is transmission connected to the jack, and the measuring rod is arranged below the worm gear reducer, and the measuring rod is transmission connected to the worm gear reducer through the torque switching device.

[0013] Furthermore, the torque switching device includes a carrying plate, a plurality of carrying rods and a sleeve, one end of the carrying rod is threadedly connected to the worm gear reducer, the other end of the carrying rod is fixed to the carrying plate by bolts, the measuring rod passes through the carrying plate and is rotatably connected to the carrying plate, one end of the sleeve is detachably connected to the end of the measuring rod, and the other end of the sleeve is transmission-connected to the output end of the worm gear reducer.

[0014] Furthermore, the detection device includes an axial force sensor, a torque sensor and a collector. The axial force sensor is arranged between the top of the jack and the reaction frame, the torque sensor is arranged at the output end of the worm gear reducer, the torque sensor is fixedly connected to the end of the sleeve away from the measuring rod, the collector is arranged on the reaction frame, and the collector is electrically connected to the axial force sensor and the torque sensor respectively.

[0015] Furthermore, the reaction frame includes a top plate, a bottom plate and a plurality of support rods, wherein the plurality of support rods are vertically arranged between the top plate and the bottom plate, the jack is arranged below the top plate, and a guide hole matching the measuring rod is opened on the bottom plate.

[0016] Furthermore, a limiting hole is opened on the carrying plate, and the measuring rod passes through the limiting hole and is rotatably connected with the limiting hole. The end of the measuring rod close to the carrying plate is in a "convex" shape, and the diameter of the part of the measuring rod that does not pass through the limiting hole is larger than the diameter of the limiting hole. The part of the measuring rod that passes through the limiting hole is opened with a pin hole, and a pin shaft is detachably connected in the pin hole.

[0017] Furthermore, the worm gear reducer is provided with a motor, which is drivingly connected to the worm gear reducer.

[0018] Furthermore, a guide bearing is installed in the guide hole, and the measuring rod is movably connected to the guide bearing.

[0019] Compared with the prior art, the beneficial effects of the utility model are:

[0020] The micro cross-plate shearing instrument provided by the utility model has a large measuring range and high precision, can improve the accuracy of measuring the vertical shear strength of soil, and can also protect the device for controlling the rotation of the cross-plate head from damage by axial force, thereby extending the service life;

[0021] The driving device is provided with supporting force by the reaction frame, and the measuring rod is driven to penetrate into and pull out of the soil by the driving device. The axial force and torque data are collected by the detection device, and the shear strength of the soil is calculated according to the axial force and torque data; the connection state between the driving device and the measuring rod is switched by the penetration-torque switching device, so as to protect the device controlling the rotation of the cross plate head from damage by the axial force and extend the service life; the accuracy of the vertical shear strength of the soil is improved by setting the height-to-diameter ratio of the micro cross plate head to be greater than or equal to 2; the measuring rod is driven to penetrate or pull out of the soil by indirect transmission between the jack and the measuring rod, and the measuring rod is driven to torsion-shear the soil by the worm gear reducer; the switching of the connection state between the measuring rod and the driving device is realized by the cooperation between the sleeve, the bearing plate and the bearing rod; the axial force and torque data are obtained by the axial force sensor, the torque sensor and the acquisition instrument; the axial force on the measuring rod is transmitted to the bearing plate through the limit hole, and the measuring rod is limited in the axial direction by the setting of the pin shaft and the pin hole to prevent the measuring rod from falling. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 A schematic structural diagram of a micro cross plate shearing instrument from one viewing angle provided by an embodiment of the utility model;

[0023] Figure 2 for Figure 1 Enlarged structural diagram of the center torque switching device.

[0024] The markings in the attached drawings are: 1. reaction frame; 101. top plate; 102. bottom plate; 103. support rod; 2. driving device; 201. jack; 202. worm gear reducer; 3. torque switching device; 301. bearing plate; 302. bearing rod; 303. sleeve; 4. detection device; 401. axial force sensor; 402. torque sensor; 5. measuring rod; 6. micro cross plate head; 7. guide hole; 8. limit hole; 9. pin shaft; 10. motor; 11. guide bearing; 12. fixing screw. DETAILED DESCRIPTION

[0025] The technical solution of the present application is further described in detail below in conjunction with specific implementation methods.

[0026] The embodiments of the present application are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements with the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present application, and should not be construed as limitations on the present application. In the absence of conflict, the embodiments of the present application and the technical features in the embodiments may be combined with each other.

[0027] This embodiment provides a micro cross plate shearing instrument, such as Figure 1As shown, it includes a reaction frame 1 for bearing the reaction force of the driving device 2. The reaction frame 1 includes a top plate 101, a bottom plate 102 and a plurality of support rods 103. The plurality of support rods 103 are vertically arranged between the top plate 101 and the bottom plate 102, and the reaction frame 1 provides support force for the driving device 2;

[0028] A driving device 2 is used to drive the measuring rod 5 to penetrate into and out of the soil and to perform torsion shear on the soil;

[0029] The penetration-torsion switching device 3 is used to switch the connection state between the driving device 2 and the measuring rod 5 when the driving device 2 performs the penetration and extraction operation and the torsion and shear operation on the measuring rod 5. By switching the connection state between the driving device 2 and the measuring rod 5 through the penetration-torsion switching device 3, the device controlling the rotation of the cross plate head is protected from damage by the axial force, thereby extending the service life;

[0030] The detection device 4 is used to detect and collect the axial force and torque generated when the driving device 2 drives the measuring rod 5 to move, and calculate the shear strength of the soil according to the axial force and torque data;

[0031] Among them, the end of the measuring rod 5 is connected to a miniature cross-plate head 6, and the height-to-diameter ratio of the miniature cross-plate head 6 is greater than or equal to 2. By setting the height-to-diameter ratio of the miniature cross-plate head 6 to be greater than or equal to 2, the accuracy of the vertical shear strength of the soil is improved; the miniature cross-plate shear meter provided in this embodiment has a large measuring range and high precision, which can improve the accuracy of measuring the vertical shear strength of the soil, and can also protect the device that controls the rotation of the cross-plate head from damage by axial force, thereby extending its service life.

[0032] In this embodiment, Figure 1 As shown, the driving device 2 includes a jack 201 and a worm gear reducer 202. The jack 201 is arranged below the top plate 101 of the reaction frame 1. A guide hole 7 matching the measuring rod 5 is opened on the bottom plate 102. A guide bearing 11 is installed in the guide hole 7. The measuring rod 5 is movably connected to the guide bearing 11. The worm gear reducer 202 is arranged below the jack 201 and is transmission-connected to the jack 201. The measuring rod 5 is arranged below the worm gear reducer 202. The measuring rod 5 is transmission-connected to the worm gear reducer 202 through the penetration-torsion switching device 3. The bottom of the measuring rod 5 passes through the bottom plate 102 through the guide hole 7, and is indirectly transmitted to the measuring rod 5 through the jack 201, so as to drive the measuring rod 5 to penetrate or pull out of the soil. The worm gear reducer 202 is transmission-connected to the measuring rod 5, so as to drive the measuring rod 5 to torsion-shear the soil.

[0033] In this embodiment, Figure 1-2As shown, the torque switching device 3 includes a supporting plate 301, a plurality of supporting rods 302 and a sleeve 303. A plurality of fixing screws 12 are threadedly connected to the side wall of the sleeve 303. One end of the supporting rod 302 is threadedly connected to the worm gear reducer 202. The other end of the supporting rod 302 is fixedly connected to the supporting plate 301 by bolts. The measuring rod 5 passes through the supporting plate 301 and is rotatably connected to the supporting plate 301. One end of the sleeve 303 is detachably connected to the end of the measuring rod 5 by the fixing screw 12. The other end of the sleeve 303 is transmission-connected to the output end of the worm gear reducer 202 by the fixing screw 12. The switching of the connection state between the measuring rod 5 and the driving device 2 is realized through the cooperation between the sleeve 303, the supporting plate 301 and the supporting rod 302.

[0034] In this embodiment, Figure 1-2 As shown, the detection device 4 includes an axial force sensor 401, a torque sensor 402 and a collector. The axial force sensor 401 is arranged between the top of the jack 201 and the reaction frame 1, the torque sensor 402 is arranged at the output end of the worm gear reducer 202, the torque sensor 402 is fixedly connected to the end of the sleeve 303 away from the measuring rod 5, the collector is arranged on the reaction frame 1, and the collector is electrically connected to the axial force sensor 401 and the torque sensor 402 respectively, and the axial force and torque data are obtained through the axial force sensor 401, the torque sensor 402 and the collector.

[0035] In this embodiment, Figure 1-2 As shown, a limiting hole 8 is provided on the carrying plate 301, and the measuring rod 5 passes through the limiting hole 8 and is rotatably connected to the limiting hole 8. The end of the measuring rod 5 close to the carrying plate 301 is in a "convex" shape, and the diameter of the portion of the measuring rod 5 that does not pass through the limiting hole 8 is larger than the diameter of the limiting hole 8. A pin hole is provided in the portion of the measuring rod 5 that passes through the limiting hole 8, and a pin shaft 9 is detachably connected to the pin hole. The axial force on the measuring rod 5 is transmitted to the carrying plate 301 through the limiting hole 8. By setting the pin shaft 9 and the pin hole, the measuring rod 5 is limited in the axial direction to prevent the measuring rod 5 from falling.

[0036] In this embodiment, Figure 1 As shown, the worm gear reducer 202 is provided with a motor 10 , and the motor 10 is drivingly connected to the worm gear reducer 202 .

[0037] When using the device, first install the micro cross plate shear instrument, install several support rods 103 on the top plate 101, then fix the axial force sensor 401 on the top plate 101 with screws, connect the top of the jack 201 with the axial force sensor 401, then fix the worm gear reducer 202 to the bottom of the jack 201, fix the torque sensor 402 on the worm gear reducer 202 with screws, set one end of the sleeve 303 on the torque sensor 402, and tighten the fixing screw on the upper part of the sleeve 303. The screw 12 fixes the sleeve 303 and the torque sensor 402, and one end of the plurality of bearing rods 302 is threadedly connected to the bottom of the worm gear reducer 202. The bearing plate 301 is fixed to the end of the bearing rod 302 away from the worm gear reducer 202 by bolts. Then, the bottom plate 102 is fixed to the support rod 103. The end of the measuring rod 5 away from the micro cross plate head 6 passes through the bottom plate 102 through the guide hole 7 and the measuring rod 5 is inserted into the limiting hole 8 of the bearing plate 301. At this time, the end of the measuring rod 5 is sleeved in the sleeve 303, and the pin is fixed. 9 is inserted into the pin hole so that the measuring rod 5 is fixed on the bearing plate 301, and the installation of the micro cross plate shearing instrument is completed. When using the device for testing, the micro cross plate head 6 of the micro cross plate shearing instrument is placed in the measuring hole. During the penetration of the micro cross plate head 6, the jack 201 is controlled to operate, and the jack 201 drives the measuring rod 5 connected to it to move downward, so that the micro cross plate head 6 is penetrated into the soil. When the jack 201 reaches the target position, the jack 201 is controlled to stop operating. During the penetration of the micro cross plate head 6 into the soil, the axial force sensor 4 is used. 01 obtains axial force data. When the micro cross plate head 6 is torsionally sheared, fix the measuring rod 5 and the torque sensor 402 by tightening the fixing screw 12 under the sleeve 303 at the end of the measuring rod 5 away from the micro cross plate head 6. Then start the motor 10 to control the measuring rod 5 to rotate and torsionally shear the soil, and obtain torque data through the torque sensor 402. After the torsion shear of the micro cross plate head 6 is completed, loosen the fixing screw 12 under the sleeve 303 to disengage the measuring rod 5 from the torque sensor 402 to prevent the torque sensor 402 from being damaged by the axial force.

[0038] The above are only preferred implementations of the utility model. It should be pointed out that for those skilled in the art, several modifications and improvements can be made without departing from the concept of the utility model. These should also be regarded as the protection scope of the utility model. These will not affect the effect of the implementation of the utility model and the practicality of the patent.

Claims

1. A micro cross plate shearing instrument, characterized in that: include: A reaction frame (1) for bearing the reaction force of the driving device (2); A driving device (2) is used to drive the measuring rod (5) to penetrate into and pull out of the soil and to perform torsion shear on the soil; A penetration-torsion switching device (3) is used to switch the connection state between the driving device (2) and the measuring rod (5) when the driving device (2) performs penetration and extraction operations and twisting and shearing operations on the measuring rod (5); A detection device (4) is used to detect and collect the axial force and torque generated when the driving device (2) drives the measuring rod (5) to move; Wherein, the end of the measuring rod (5) is connected to a micro cross plate head (6), and the height-to-diameter ratio of the micro cross plate head (6) is greater than or equal to 2.

2. The micro cross plate shearing instrument according to claim 1, characterized in that: The driving device (2) comprises a jack (201) and a worm gear reducer (202); the jack (201) is arranged on the top of the reaction frame (1); the worm gear reducer (202) is arranged below the jack (201) and is transmission-connected to the jack (201); the measuring rod (5) is arranged below the worm gear reducer (202); and the measuring rod (5) is transmission-connected to the worm gear reducer (202) via the torque-through switching device (3).

3. The micro cross plate shearing instrument according to claim 2, characterized in that: The torque-through switching device (3) comprises a bearing plate (301), a plurality of bearing rods (302) and a sleeve (303); one end of the bearing rod (302) is threadedly connected to the worm gear reducer (202); the other end of the bearing rod (302) is fixedly connected to the bearing plate (301) by bolts; the measuring rod (5) passes through the bearing plate (301) and is rotatably connected to the bearing plate (301); one end of the sleeve (303) is detachably connected to the end of the measuring rod (5); and the other end of the sleeve (303) is drivingly connected to the output end of the worm gear reducer (202).

4. The micro cross plate shearing instrument according to claim 3, characterized in that: The detection device (4) comprises an axial force sensor (401), a torque sensor (402) and a data collector, wherein the axial force sensor (401) is arranged between the top of the jack (201) and the reaction frame (1), the torque sensor (402) is arranged at the output end of the worm gear reducer (202), the torque sensor (402) is fixedly connected to an end of the sleeve (303) away from the measuring rod (5), and the data collector is arranged on the reaction frame (1), and the data collector is electrically connected to the axial force sensor (401) and the torque sensor (402), respectively.

5. The micro cross plate shearing instrument according to claim 2, characterized in that: The reaction frame (1) comprises a top plate (101), a bottom plate (102) and a plurality of support rods (103), wherein the plurality of support rods (103) are vertically arranged between the top plate (101) and the bottom plate (102), the jack (201) is arranged below the top plate (101), and a guide hole (7) matching the measuring rod (5) is provided on the bottom plate (102).

6. The micro cross plate shearing instrument according to claim 3, characterized in that: The carrier plate (301) is provided with a limiting hole (8), the measuring rod (5) passes through the limiting hole (8) and is rotatably connected to the limiting hole (8), the end of the measuring rod (5) close to the carrier plate (301) is in a "convex" shape, the diameter of the portion of the measuring rod (5) that does not pass through the limiting hole (8) is larger than the diameter of the limiting hole (8), and the portion of the measuring rod (5) that passes through the limiting hole (8) is provided with a pin hole, and a pin shaft (9) is detachably connected to the pin hole.

7. The micro cross plate shearing instrument according to claim 2, characterized in that: The worm gear reducer (202) is provided with a motor (10), and the motor (10) is drivingly connected to the worm gear reducer (202).

8. The micro cross plate shearing instrument according to claim 5, characterized in that: A guide bearing (11) is installed in the guide hole (7), and the measuring rod (5) is movably connected to the guide bearing (11).

Images