CN204694539U - Tensile sample's centering device - Google Patents

Abstract

A centering device for tensile samples can conveniently and quickly realize the precise centering of tensile samples of metal and non-metal sheet materials with different widths. The device includes a driving mechanism, a driven mechanism, a detection mechanism, an insulated wire, a conductive plate, and an operating table. A chuck hole is arranged on the operating table, and the chuck is arranged in the chuck hole, which is symmetrical at both ends of the operating table. Install two sets of driven mechanisms. The symmetrical plane of the two sets of driven mechanisms is the vertical plane of the chuck working surface. The sets of rods on the two sets of driven mechanisms are coaxially arranged. The surface coincides with the symmetrical plane of the two sets of driven mechanisms, the active mechanism and the two sets of driven mechanisms are connected by two insulated wires, and the two insulated wires are equal in length, and the detection mechanism is connected with the sleeve rods of the two driven mechanisms through copper wires; When the non-metallic plate sample is centered, the conductive plate is pasted on the surface of the sample, and the transverse center line of the conductive plate is on the same horizontal plane as the axes of the two sets of rods.

Description

A centering device for a tensile sample

technical field

The utility model relates to the field of material mechanical performance testing, in particular to a centering device for multi-standard tensile samples with high requirements for testing process accuracy.

Background technique

With the continuous deepening of material science research, people have higher and higher requirements for the rigor of the test process and the accuracy of the test results. In some non-standard tests of engineering mechanics, the specifications of the samples are often different, and the neutrality requirements of the test process are very high, that is, it is necessary to ensure that the centerline of the sample and the centerline of the chuck are completely coincident, so that Avoid the influence of additional shear force, bending moment, torque, etc. on the sample during the uniaxial stretching process, resulting in abnormal performance indicators such as yield strength.

During the conventional tensile test, the centering is realized by adjusting the positioning device located on the side of the sample on the testing machine, and the length of the positioning ruler is continuously adjusted to ensure that the sample is vertical. The "vertical centering fixture for tensile testing machine specimen" disclosed in the patent document with the authorized announcement number CN201707256U is an improvement on the conventional positioning ruler. The patent document CN101598526A discloses "a testing machine sample automatic centering device" which has a higher degree of automation. However, for tensile samples of different specifications, especially different widths, it is difficult to ensure that the centerline of the sample and the centerline of the gripper completely coincide with the above-mentioned centering method, so that it is difficult to achieve accurate centering.

Contents of the invention

The purpose of the utility model is to provide a centering device for tensile samples, which can conveniently and quickly realize the precise centering of the tensile samples of metal and non-metal sheet materials with different width specifications.

In order to achieve the above object, the utility model adopts the following technical solutions:

A centering device for a tensile sample, comprising a driving mechanism, a driven mechanism, a detection mechanism, an insulated wire, a conductive plate, and an operating table, where a chuck hole is arranged on the operating table, and the chuck is arranged in the chuck hole Among them, two sets of driven mechanisms are installed symmetrically at both ends of the chuck hole of the console. The symmetrical plane of the two sets of driven mechanisms is the vertical plane of the working surface of the chuck. The sleeve rods on the two sets of driven mechanisms are coaxially arranged. The active mechanism is installed on the console, the symmetrical plane of the active mechanism coincides with the symmetrical plane of the two sets of driven mechanisms, one end of the insulated wire is fixedly connected with the sleeve rod of the driven mechanism, and the other end of the insulating wire passes through the active mechanism. The cylinder is fixedly connected with the frame, the connection point between the insulating wire and the frame is on the symmetrical plane of the active mechanism, the two insulated wires connecting the driven mechanism and the active mechanism are equal in length, and the detection mechanism is respectively connected to the two driven mechanisms through copper wires. When centering the non-metallic plate sample, the conductive plate is pasted on the surface of the sample, and the transverse centerline of the conductive plate is on the same level as the axes of the two sets of rods.

The active mechanism includes a cylinder, a slider, a screw, a screw bracket, a rotating hand wheel, and a frame. The slider is placed on the console, and the upper end of the slider is symmetrically welded with the longitudinal centerline of the slider. A cylinder, threaded holes are set in the slider, the frame is fixed on the console, the lead screw passes through the ratchet hole in the frame and the threaded hole of the slider in turn, the lead screw and the ratchet are radially fixed, and the two ends of the lead screw are set On the lead screw support, the lead screw support is fixed on the operating platform, and a rotating hand wheel is installed at the operating end of the lead screw.

The frame includes a frame body, a ratchet wheel and a ratchet. The bottom of the frame body is fixedly connected with the operating table, and a ratchet and a ratchet wheel that cooperate with each other are arranged below the frame body.

The driven mechanism includes a sleeve, a sleeve rod, an insulating pad, a connection terminal, and a fixing ring. The insulating pad is fixed on the console, the sleeve is fixed on the upper end of the insulating pad, the sleeve rod is arranged inside the sleeve, and the sleeve and the sleeve The rods are fitted with gaps, the fixing ring is fixed on the end of the sleeve rod close to the chuck, the fixing ring is connected with the insulated wire, and the terminal is fixed on the sleeve rod.

The detection mechanism includes a multimeter and a copper wire, and the positive and negative poles of the multimeter are respectively connected to the copper wire.

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

A centering device for a tensile sample, in which two sets of rods are symmetrically arranged at both ends of the sample clamp with the middle vertical plane of the clamp working surface as the symmetrical plane, and the distance between the sets of rods at both ends of the sample can be adjusted synchronously. The set rod drives the sample to be automatically centered, so that the accurate centering of the tensile samples of metal and non-metal plate types with different width specifications can be realized conveniently and quickly.

Description of drawings

Fig. 1 is a structural schematic diagram of a centering device of a tensile sample of the present invention;

Fig. 2 is the structural representation of frame in the utility model;

In the figure: 1. Chuck; 2. Active mechanism; 3. Sample; 4. Insulated wire; 5. Driven mechanism; 6. Detection mechanism; 7. Cylinder; 8. Console; 9. Slider; 10 1, lead screw; 11, lead screw bracket; 12, rotating handwheel; 13, sleeve; 14, sleeve rod; 15, insulating pad; 16, terminal block; 17, fixed ring; 18, frame; 19, pawl; 20, ratchet; 21, multimeter; 22, copper wire; 23, conductive plate.

Detailed ways

The utility model is described in detail below in conjunction with the accompanying drawings, but it should be pointed out that the implementation of the utility model is not limited to the following embodiments.

As shown in Figures 1-2, a centering device for a tensile sample includes a driving mechanism 2, a driven mechanism 5, a detection mechanism 6, an insulating wire 4, a conductive plate 23, and an operating table 8. There is a collet hole on the platform 8, and the collet 1 is arranged in the collet hole. Two sets of driven mechanisms 5 are symmetrically installed at both ends of the collet hole of the operating table 8, and the symmetrical plane of the two sets of driven mechanisms 5 is the collet. 1. On the vertical surface of the working surface, the sleeve rods 14 on the two sets of driven mechanisms 5 are arranged coaxially. The active mechanism 2 is installed on the console 8. The surfaces overlap, one end of the insulated wire 4 is fixedly connected to the sleeve rod 14 of the driven mechanism 5, the other end of the insulated wire 4 passes through the cylinder 7 on the active mechanism 2 and is fixedly connected to the frame 18, and the connection between the insulated wire 4 and the frame 18 The point is on the symmetrical plane of the active mechanism 2, the two insulated wires 4 connecting the driven mechanism 5 and the active mechanism 2 are equal in length, and the detection mechanism 6 is respectively connected with the cover rods 14 of the two driven mechanisms 5 by copper wires 22; When the sample 3 of the non-metal plate type is centered, the conductive plate 23 is pasted on the surface of the sample 3 facing the active mechanism 2. When pasting, the transverse centerline of the conductive plate 23 and the axes of the two sleeve rods 14 are on the same horizontal plane superior. The length of the conductive plate 23 is equal to the width of the sample 3 and has a certain thickness and width.

The insulated wire 4 is an inelastic soft insulated wire.

Described active mechanism 2 comprises cylinder 7, slide block 9, leading screw 10, leading screw support 11, rotating handwheel 12, frame 18, and slide block 9 is placed on the operating table 8, and slide block 9 is arranged on the upper end of slide block 9. The longitudinal centerline of 9 is the axis of symmetry, two cylinders 7 are welded symmetrically, threaded holes are provided in the slider 9, the frame 18 is fixed on the console 8, and the lead screw 10 passes through the inner hole of the ratchet 20 in the frame 18 in turn , Slider 9 threaded holes, lead screw 10 and ratchet 20 radially fixed, the two ends of lead screw 10 are arranged on the lead screw support 11, lead screw support 11 is fixed on the console 8, is installed on the operation end of lead screw 10 There are 12 rotating handwheels. The screw support 11 is connected with the screw 10 through a sliding bearing bush.

The axis of the cylinder 7 at the upper end of the sliding block 9 of the driving mechanism 2 is on the same level as the axis of the sleeve rod 14 of the driven mechanism 5 .

The active mechanism 2 has a symmetrical structure as a whole, and the longitudinal centerline of the slider 9 , the axis of symmetry of the cylinder 7 and the centerline of the lead screw 10 all fall on the symmetrical plane of the active mechanism 2 .

The frame 18 includes a frame body, a ratchet wheel 20, and a ratchet wheel 19. The bottom of the frame body is fixedly connected with the console 8, and the ratchet pawl 19 and the ratchet wheel 20 are arranged below the frame body. The inner hole of the ratchet 20 is provided with a keyway, and the lead screw 10 is radially fixed to the ratchet 20 through the key.

The driven mechanism 5 comprises a sleeve 13, a sleeve rod 14, an insulating pad 15, a connection terminal 16, and a fixing ring 17. The insulating pad 15 is fixed on the console 8, the sleeve 13 is fixed on the upper end of the insulating pad 15, and the sleeve rod 14 Set inside the sleeve 13, the sleeve 13 and the sleeve rod 14 are in clearance fit, the fixing ring 17 is fixed on the end of the sleeve rod 14 close to the collet 1, the fixing ring 17 is connected to the insulated wire 4, and the terminal 16 is fixed on the sleeve rod 14 Outer end.

The fixing ring 17 is welded on the sleeve rod 14 towards the side of the active mechanism 2, and the positions of welding the fixing ring 17 on the two sleeve rods 14 should be the same.

The detection mechanism 6 includes a multimeter 21 and a copper wire 22, and the positive and negative poles of the multimeter 21 are respectively connected to the copper wire 22. The other end of the copper wire 22 is connected to the connection terminal 16 on the sleeve rod 14 .

Embodiment 1, the method for centering the sample 3 of the sheet metal type by using a centering device of a tensile sample, comprises the following method steps:

1) Put the sample 3 between the two chucks 1, tighten the chuck 1 so that the gap between the chuck 1 and the sample 3 is as small as possible but not equal to zero;

2) Check the wire connection circuit to ensure that the copper wire 22 is correctly connected to each mechanism, turn on the multimeter 21, and dial it to the resistance level;

3) Turn the rotating handwheel 12 (when the thread of the lead screw 10 is a right-handed thread, turn the rotating handwheel 12 counterclockwise; when the thread of the lead screw 10 is a left-handed thread, turn the rotating handwheel 12 clockwise) , so that the slider 9 drives the cylinder 7 to move toward the sample 3, and at this time, the insulating wire 4 drives the two sleeve rods 14 to move toward the sample 3 under the action of the cylinder 7;

When the sleeve rod 14 on one side touches the sample 3, it will push the sample 3 to the other direction. Since the two sleeve rods 14 are arranged symmetrically with the vertical plane of the working surface of the chuck 1 as the symmetrical plane, Therefore, when both sleeve rods 14 fully contact the sample 3, the two ends of the sample 3 will be automatically and accurately centered.

4) When the two sleeve rods 14 fully contact the sample 3, immediately check the reading of the multimeter 21. If the resistance is zero, loosen the rotating handwheel 12. At this time, the ratchet 19 in the frame 18 locks the ratchet 20, thereby Lock the slider 9 and the sleeve rod 14 and no longer shift;

5) If the resistance is not zero, continue to turn the rotating handwheel 12 until the resistance shows zero;

After the two sleeve rods 14 are in full contact with the sample 3, the detection circuit will be connected, and the resistance value of the multimeter 21 will display zero at this time, so it can be used as a standard for observing whether the sample 3 is centered.

6) Fully clamp the chucks 1 on both sides of the sample 3, and fix the centered sample 3 well.

In this embodiment, the diameter of the cylinder 7 is 4 mm, the diameter of the insulated wire 4 is 3 mm, and the axial length of the ratchet 20 sleeved on the lead screw 10 is 50 mm. Sample 3 has a width of 25 mm.

Embodiment 2, when sample 3 is non-metal plate type, comprises the following method steps:

1) Put the sample 3 between the two chucks 1, tighten the chuck 1 so that the gap between the chuck 1 and the sample 3 is as small as possible but not equal to zero;

2) Paste the conductive plate 23 on the surface of the sample 3 on the side of the active mechanism 2, ensure that the center line of the conductive plate 23 is on the same level as the axis of the sleeve rod 14, and ensure that the sleeve rod 14 is in full contact with the sample 3 , will also fully contact with the conductive plate 23;

3) Check the wire connection circuit to ensure that the copper wire 22 is correctly connected to each mechanism, turn on the multimeter 21, and dial it to the resistance level;

4) Turn the rotating handwheel 12 (when the thread of the lead screw 10 is a right-handed thread, turn the rotating handwheel 12 counterclockwise; when the thread of the lead screw 10 is a left-handed thread, turn the rotating handwheel 12 clockwise) , so that the slider 9 drives the cylinder 7 to move toward the sample 3, and at this time, the insulating wire 4 drives the two sleeve rods 14 to move toward the sample 3 under the action of the cylinder 7;

5) When the two sets of rods 14 fully contact the sample 3 and the conductive plate 23 on the sample 3, check the reading of the multimeter 21 immediately. If the resistance is zero, loosen the rotating handwheel 12. At this time, the ratchet in the frame 18 The pawl 19 locks the ratchet 20, thereby locking the slider 9 and the sleeve rod 14 from displacement;

6) If the resistance is not zero, continue to turn the rotating handwheel 12 until the resistance shows zero;

7) Fully clamp the chucks 1 on both sides of the sample 3, and fix the centered sample 3 well.

In this embodiment, the diameter of the cylinder 7 is 4 mm, the diameter of the insulated wire 4 is 3 mm, and the axial length of the ratchet 20 sleeved on the lead screw 10 is 50 mm. Sample 3 has a width of 40 mm.

Claims (5)

1. A centering device for a tensile sample, characterized in that: it comprises a driving mechanism, a driven mechanism, a detection mechanism, an insulated wire, a conductive plate, and an operating table, on which the operating table is provided with chuck holes, clamping The head is set in the chuck hole, and two sets of driven mechanisms are installed symmetrically at both ends of the chuck hole of the console. The symmetrical plane of the two sets of driven mechanisms is the vertical plane of the working surface of the chuck. The sleeve rods are coaxially arranged, the active mechanism is installed on the console, the symmetrical plane of the active mechanism coincides with the symmetrical planes of the two sets of driven mechanisms, one end of the insulated wire is fixedly connected with the sleeve rod of the driven mechanism, and the other end of the insulated wire One end passes through the cylinder on the active mechanism and is fixedly connected to the frame. The connection point between the insulating wire and the frame is on the symmetrical plane of the active mechanism. The two insulated wires connecting the driven mechanism and the active mechanism are equal in length. It is connected with the sleeve rods of the two driven mechanisms; when centering samples of non-metallic plate types, the conductive plate is pasted on the surface of the sample, and the transverse centerline of the conductive plate is on the same level as the axes of the two sleeve rods. 2. A centering device for tensile samples according to claim 1, characterized in that: the active mechanism includes a cylinder, a slider, a screw, a screw bracket, a rotating hand wheel, a frame, and a slider Place it on the console, take the longitudinal center line of the slider as the symmetrical axis at the upper end of the slider, weld two cylinders symmetrically, set threaded holes in the slider, fix the frame on the console, and pass the screw through the frame in turn The inner ratchet hole, the threaded hole of the slider, the screw and the ratchet are radially fixed, the two ends of the screw are set on the screw bracket, the screw bracket is fixed on the operation table, and the rotating hand wheel is installed at the operating end of the screw . 3. A centering device for tensile samples according to claim 2, characterized in that: the frame includes a frame, a ratchet, and a pawl, the bottom of the frame is fixedly connected to the operating table, and A pawl and a ratchet that cooperate with each other are arranged below. 4. A centering device for tensile samples according to claim 1, characterized in that: the driven mechanism includes a sleeve, a sleeve rod, an insulating pad, a connection terminal, and a fixing ring, and the insulating pad is fixed in the operation On the platform, the sleeve is fixed on the upper end of the insulating pad, the sleeve rod is set inside the sleeve, the sleeve and the sleeve rod are in clearance fit, the fixing ring is fixed on the end of the sleeve rod close to the chuck, the fixing ring is connected to the insulating wire, and the terminal is fixed on the set on the pole. 5 . The centering device for tensile samples according to claim 1 , wherein the detection mechanism includes a multimeter and copper wires, and the positive and negative electrodes of the multimeter are respectively connected to the copper wires. 5 .