CN113551980A - Multi-shaft type tensile test testing machine and testing method - Google Patents
Multi-shaft type tensile test testing machine and testing method Download PDFInfo
- Publication number
- CN113551980A CN113551980A CN202110969295.3A CN202110969295A CN113551980A CN 113551980 A CN113551980 A CN 113551980A CN 202110969295 A CN202110969295 A CN 202110969295A CN 113551980 A CN113551980 A CN 113551980A
- Authority
- CN
- China
- Prior art keywords
- stretching
- connecting rod
- sample
- motor
- tensile
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Withdrawn
Links
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N3/00—Investigating strength properties of solid materials by application of mechanical stress
- G01N3/02—Details
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N3/00—Investigating strength properties of solid materials by application of mechanical stress
- G01N3/02—Details
- G01N3/04—Chucks
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N3/00—Investigating strength properties of solid materials by application of mechanical stress
- G01N3/08—Investigating strength properties of solid materials by application of mechanical stress by applying steady tensile or compressive forces
Landscapes
- Physics & Mathematics (AREA)
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Chemical & Material Sciences (AREA)
- Analytical Chemistry (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- General Physics & Mathematics (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Investigating Strength Of Materials By Application Of Mechanical Stress (AREA)
Abstract
The invention discloses a multi-axis tensile test testing machine and a testing method. The mechanical structure comprises a motor, a coupler, a guide rail, a turntable, a connecting rod, a sliding block, a supporting plate, a clamp and the like. The motor is connected with the rotary table through the coupler, and the rotary motion of the rotary table is converted into the linear motion of the slide block driving the clamp through the connecting rod, so that the tested sample is driven to realize periodic stretching. The tester realizes synchronous stretching of samples under different frequencies by using a crank-link mechanism. The stretching ratio can be flexibly adjusted by adjusting the relative positions of the key slot on the turntable and the threaded hole on the connecting rod, and the stretching ratio is adapted to the size of a sample. The invention has the advantages of large stretching deformation, easy adjustment of stretching range, simple structure, convenient installation, low manufacturing cost and the like.
Description
Technical Field
The invention belongs to the technical field of electromechanics, and relates to a multi-shaft type tensile test testing machine and a testing method.
Background
In the field of electro-mechanical technology, it is often necessary to produce large deformations in a material in order to better measure certain properties of the material.
In the prior art, most of the tensile testing machines for materials are in a uniaxial form, the deformation amount of the tensile form is not large enough, the speed is slow, and the experimental requirements of large-scale variables and high tensile frequency cannot be met frequently. Some biaxial tensile test testers basically adopt a transmission form of a ball screw, and the transmission form has large friction force, high mechanical energy consumption and poor stability, and is not beneficial to tensile test of materials. Some multi-axis tensile test testing machines have complex structures, numerous parts, complex installation, high manufacturing cost and unadjustable tensile range.
Compared with the prior art, on one hand, the multi-shaft type tensile test testing machine provided by the invention has enough tensile deformation, and the key groove arranged on the turntable enables the tensile range to be adjusted more conveniently; on the other hand, present stretching device is mostly screw drive or cylinder drive, and these two kinds of transmission mode speed are slower to motor rotational frequency is little to the tensile frequency influence of device, if need adjustment frequency by a wide margin, needs to dismantle the drive mechanism of device. However, the transmission mechanism of the tensile testing machine provided by the invention is directly connected with the motor, the rotation frequency of the motor directly determines the motion frequency of the motor, the tensile frequency of the adjusting device is convenient, and the adjustable range is large. Finally, most of the existing stretching devices require that the shape and the size of the sample are fixed, so that the testing is convenient, but the stretching testing machine provided by the invention is provided with a plurality of threaded holes on the connecting rod, so that the device can conveniently perform the stretching testing on samples with different sizes.
Disclosure of Invention
Aiming at the defects of the prior art, the invention provides a multi-shaft type tensile test testing machine and a testing method, and aims to solve the technical problems that a material tensile device in the prior art is small in deformation amount, the testing frequency of the device is not adjustable, and the like.
In order to achieve the above object, a first aspect of the present invention provides a multi-axis tensile testing machine, which is formed by fixing a plurality of uniaxial tensile devices on a base;
each single-shaft stretching device comprises a power mechanism and a stretching mechanism, wherein the stretching mechanism is fixed on a test bed positioned on the base and comprises a sliding block, a guide rail, a first supporting plate and a clamp; the test bed is provided with a linear guide rail with a slide block; the clamp is arranged on the sliding block through the first supporting plate and can slide along the linear guide rail through the sliding block;
the power mechanism comprises a motor, a coupler, a rotary disc, a first fastening screw and a connecting rod; the motor is connected with the center of the turntable through the coupler, the turntable is provided with a radial notch, one end of the connecting rod is connected with the notch on the turntable through a first fastening screw, one end of the connecting rod can rotate by taking the first fastening screw as a supporting shaft, and the other end of the connecting rod is connected with the sliding block;
the two-by-two symmetry of a plurality of uniaxial tension devices is arranged on the base, and the included angle between the guide rails in two adjacent uniaxial tension devices is equal.
Preferably, the connecting rod is provided with a plurality of threaded holes, the first fastening screw penetrates through one of the threaded holes to be fixed at the notch of the turntable, and the sample stretching amount is changed by adjusting the position of the threaded hole mounted by the first fastening screw.
The connecting rod is characterized by further comprising a second supporting plate and a second fastening screw, wherein the second supporting plate is mounted on the sliding block, and the other end of the connecting rod is fixed on the second supporting plate on the sliding block through the second fastening screw; the other end of the connecting rod can rotate by taking the second fastening screw as a supporting shaft.
Preferably, the first support plate and the second support plate are adjustable in height.
Preferably, in each of the uniaxial stretching apparatuses, the motor is located in the extending direction of the guide rail.
Preferably, the edge of the clamp is provided with a smooth chamfer.
In a second aspect of the present invention, a testing method of the multi-axis tensile testing machine is provided, which includes the following steps:
1) fixing a plurality of uniaxial stretching devices on a base according to the stretching requirement of a sample to be tested, and symmetrically arranging a pair of uniaxial stretching devices at each position to be stretched of the sample; adjusting the heights of the first supporting plate and the second supporting plate to enable all the clamps to be located on the same horizontal plane, wherein the connecting rod in each uniaxial stretching device is parallel to the test bed;
2) determining the stretching amount of the sample, adjusting the position of a first fastening screw in each uniaxial stretching device according to the stretching amount, and fixing the sample by a clamp;
3) and setting a motor program to enable the motor to move completely synchronously, driving the turntable to rotate by the motor through the coupler, converting the rotary motion of the turntable into periodic linear motion through the connecting rod, and driving the sliding block to drive the clamp to reciprocate on the guide rail to stretch the tested sample.
Furthermore, the stretching frequency of the clamp to the tested sample is changed by adjusting the rotating speed of the motor.
Compared with the prior art, the invention has the advantages that:
1. the connecting rod is provided with a plurality of threaded holes, the threaded holes at different positions can be adjusted according to actual requirements, and the connecting rod is connected with the rotary table through the fastening screws, so that samples with different sizes can be tested, and the difference between the maximum length and the minimum length of the sample which can be measured is the distance between the center points of the threaded holes at two ends.
2. The multi-shaft type tensile testing machine provided by the invention has a modular structure and a knotThe structure is simple and the assembly is convenient; through arranging different quantity's unipolar stretching device, can realize multiaxis stretching forms such as surveyed sample biax, triaxial, four-axis. For example, when a biaxial tensile test is performed on a sample, four tensile modules are spaced 90 apart°Placing; when the sample is subjected to a triaxial tensile test, six tensile modules are separated by 60°Placing; when four-axis and above tensile test is carried out, only need according to actual demand symmetry or asymmetric place corresponding quantity module can.
3. The invention can adjust the running speed of the crank connecting rod by adjusting the rotating speed of the motor, thereby realizing the adjustment of the sample tensile test frequency from high frequency to low frequency. Compared with the traditional stretching device which takes a threaded screw and a spring as a transmission mechanism, the traditional scheme has slower stretching frequency and is difficult to meet the requirement of high-frequency stretching; compared with the traditional stretching device which drives the clamp by an electric cylinder, the traditional scheme has the advantages that although the stretching speed is adjustable, the structure is extremely complex, and strict requirements are imposed on the shape and/or the size of a sample to be measured. According to the invention, through the crank-link mechanism consisting of the turntable and the connecting rod, the output rotating speed of the motor can be effectively converted into the stretching frequency of the device, when the motor rotates for one circle, the stretching device can stretch the sample for one time without reducing the transmission ratio, the device can be easily adjusted according to the actual shape and size of the sample according to the relative matching position of the radial notch on the turntable and the threaded hole on the connecting rod, the adjusting range is related to the radius of the turntable, the positions of the radial notch and the threaded hole of the connecting rod, and the application range is wide.
Drawings
FIG. 1 is a schematic view of an overall single module in a multi-axis tensile testing machine;
FIG. 2 is a front view of a single module in a multi-axis tensile testing machine;
FIG. 3 is a top view of a single module of the multi-axis tensile tester;
FIG. 4 is a schematic overall structure diagram of the first embodiment of the present invention;
FIG. 5 is a schematic overall structure diagram of a second embodiment of the present invention;
FIG. 6 is a schematic view of a third embodiment of a clamping fixture according to the present invention;
FIG. 7 is a graph showing the change in capacitance of a test sample;
in the figure: 1-motor, 2-coupler, 3-rotary table, 4-first fastening screw, 5-connecting rod, 6-second fastening screw, 7-second supporting plate, 8-sliding block, 9-guide rail, 10-first supporting plate, 11-clamp, 12-test bench and 13-base.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention. In addition, the technical features involved in the embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.
The invention provides a multi-shaft type tensile test testing machine which is formed by fixing a plurality of single-shaft tensile devices on a base. Fig. 1-3 show schematic views of a single uniaxial stretching apparatus from different perspectives.
The uniaxial tension device comprises a motor 1, a coupler 2, a rotary table 3, a first fastening screw 4, a connecting rod 5, a second fastening screw 6, a second supporting plate 7, a sliding block 8, a guide rail 9, a first supporting plate 10, a clamp 11, a test bed 12 and a base 13.
The test bed 12 is provided with a linear guide rail 9 with a slide block 8; the clamp 11 is mounted on the slide block 8 through the first support plate 10 and can slide along the linear guide rail 9 through the slide block 8.
The motor 1 through the central point that 2 connection turntables 3 of shaft coupling put, turntables 3 on be equipped with radial notch, 5 one end of connecting rod be connected through the notch on first fastening screw and the turntables, connecting rod one end can regard as the back shaft orbit with first fastening screw, the 5 other ends of connecting rod are connected with the slider. In this embodiment, the motor is located in the extending direction of the guide rail.
In order to enable the connecting rod to be horizontal to the test bed and facilitate power transmission, the uniaxial tension device further comprises a second supporting plate 7 and a second fastening screw 6, wherein the second supporting plate 7 is installed on the sliding block, and the other end of the connecting rod 5 is fixed on the second supporting plate on the sliding block through the second fastening screw; the other end of the connecting rod can rotate by taking the second fastening screw as a supporting shaft. The height of the first supporting plate and the second supporting plate is adjustable.
In this embodiment, the testing machine uses a servo motor. Compared with a stepping motor or a linear motor used by most existing tensile testing machines, the rotation of the servo motor is more stable and accurate. Therefore, the testing machine can accurately realize equiaxial tensile test. The turntable, the connecting rod, the sliding block and the supporting plate are all made of PMMA materials, and assembly is facilitated.
In one embodiment of the invention, the connecting rod 5 is provided with a plurality of threaded holes, the first fastening screw 4 passes through one of the threaded holes and is fixed at the notch of the rotary table 3, the sample stretching amount is changed by adjusting the position of the threaded hole for mounting the first fastening screw, and the device can be suitable for sample tests in various shapes and sizes according to the relative matching position of the notch on the rotary table 3 and the threaded hole on the connecting rod, so that the device has a wide application range.
The multi-shaft type tensile testing machine provided by the invention can realize multi-shaft stretching of a tested sample by reasonably arranging the positions of the stretching modules, so that the deformation of the sample is larger, the multi-shaft type tensile testing machine is easy to regulate and control, the assembly mode is simple, and the multi-shaft type tensile testing machine is convenient to install.
The multi-shaft type tensile test testing machine provided by the invention effectively converts the output rotating speed of the motor into the tensile frequency of the device through adjusting the rotating speed of the motor and through the crank-link mechanism consisting of the turntable and the link, when the motor rotates for one circle, the tensile device stretches a sample once, the adjustment of the tensile frequency of the tested sample is realized under the condition of not reducing the transmission ratio, and the obtained test results are basically the same under the high-frequency state and the low-frequency state.
Referring to fig. 4, four identical stretching modules are symmetrically placed two by two, the interval between adjacent stretching modules is 90 °, a motor program is set, the motion of the motor is completely synchronous, and the relative positions of each part in the stretching modules are also completely identical. In this state, the deformation amounts of the sample to be measured in the four directions are identical.
Before testing, the heights of the first supporting plate 10 and the second supporting plate 7 are adjusted, so that all the clamps 11 are positioned on the same horizontal plane, and the connecting rod 5 in each uniaxial tension device is parallel to the test bed 12; the position of the first fastening screw 4 in each stretching module is then adjusted according to the stretching amount of the sample, and the sample is fixed by the clamp 11.
During the test, motor 1 drives carousel 3 through shaft coupling 2 and rotates, converts the rotary motion of carousel 3 into periodic linear motion through connecting rod 5, and drive slider 8 drives anchor clamps 11 reciprocating motion on guide rail 9, realizes the drawing to the sample that is surveyed.
Referring to fig. 5, six identical stretching modules are symmetrically placed two by two, the interval between adjacent stretching modules is 60 degrees, a motor program is set, so that the motion of the motor is completely synchronous, and the relative positions of all parts in the stretching modules are also completely identical. In this state, the deformation amount of the sample to be measured in the six directions is identical, and the deformation amount is larger compared with fig. 4.
Referring to fig. 6, the edge of the acrylic plate (clamp) directly connected to the sample to be measured in the stretching module is smoothed, so that the sample to be measured is not subjected to a large stress at the sharp position of the edge of the acrylic plate to be broken when the sample to be measured is stretched.
A testing machine was assembled using the arrangement described in fig. 4 for tensile testing of the dielectric elastomer film. Dielectric Elastomers (DE) are one type of electroactive polymer (EAP). Under the stimulation of an external electric field, the DE material can remarkably change the shape of the DE material, and when the external electric field is eliminated, the DE material can restore to the original shape; in addition, the effect is reversible, and the dielectric elastomer material deforms and can generate corresponding changes of the electric signals. Thus, the dielectric elastomer material can operate in both drive and generate power modes. When the dielectric elastomer is subjected to external stimulation to generate tensile deformation, the opposite area between the upper electrode and the lower electrode is increased, and the distance is reduced. As can be seen from the formula C ═ Q/U, the capacitance of the dielectric elastomer film increases. When the deformation of the dielectric elastomer is restored, the capacitance is also synchronously restored to the initial value. Referring to fig. 7, it can be found that the tensile test tester proposed by the present invention realizes a tensile test with a frequency from 0.5Hz to 2Hz, and the test result is substantially free from errors.
It is understood that the present embodiment describes the tensile testing of dielectric elastomers, but the present invention is not limited thereto, and it is also possible to perform the tensile testing of different frequencies for other kinds of samples.
It will be understood by those skilled in the art that the foregoing is only a preferred embodiment of the present invention, and is not intended to limit the invention, and that any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the scope of the present invention.
Claims (8)
1. A multi-shaft type tensile test testing machine is characterized in that the testing machine is formed by fixing a plurality of single-shaft tensile devices on a base (13);
each single-shaft stretching device comprises a power mechanism and a stretching mechanism, wherein the stretching mechanism is fixed on a test bed (12) positioned on the base and comprises a sliding block (8), a guide rail (9), a first supporting plate (10) and a clamp (11); the test bed (12) is provided with a linear guide rail (9) with a slide block (8); the clamp (11) is arranged on the sliding block (8) through a first supporting plate (10) and can slide along the linear guide rail (9) through the sliding block (8);
the power mechanism comprises a motor (1), a coupler (2), a rotary table (3), a first fastening screw (4) and a connecting rod (5); the motor (1) is connected with the center of the rotary table (3) through the coupler (2), a radial notch is formed in the rotary table (3), one end of the connecting rod (5) is connected with the notch in the rotary table through a first fastening screw, one end of the connecting rod can rotate around by taking the first fastening screw as a supporting shaft, and the other end of the connecting rod (5) is connected with the sliding block;
the two-by-two symmetry of a plurality of uniaxial tension devices is arranged on the base, and the included angle between the guide rails in two adjacent uniaxial tension devices is equal.
2. The multi-axial tensile testing machine according to claim 1, wherein the connecting rod (5) is provided with a plurality of threaded holes, the first fastening screw (4) passes through one of the threaded holes and is fixed at the notch of the rotary table (3), and the sample tensile amount is changed by adjusting the position of the threaded hole where the first fastening screw is installed.
3. The multi-axis tensile test testing machine according to claim 2, further comprising a second supporting plate (7) and a second fastening screw (6), wherein the second supporting plate (7) is mounted on the sliding block, and the other end of the connecting rod (5) is fixed on the second supporting plate on the sliding block through the second fastening screw; the other end of the connecting rod can rotate by taking the second fastening screw as a supporting shaft.
4. The multi-axial tensile test tester according to claim 1, wherein the first support plate and the second support plate are adjustable in height.
5. The multi-axial tensile testing machine according to claim 1, wherein in each of the uniaxial tensile devices, the motor is located in an extending direction of the guide rail.
6. The multi-axial tensile test tester according to claim 1, wherein said jig edge is provided with a smooth chamfer.
7. A test method of the multi-axis tensile tester according to claim 3, comprising the steps of:
1) according to the stretching requirement of a sample to be tested, a plurality of uniaxial stretching devices are fixed on a base (13), and a pair of uniaxial stretching devices is symmetrically arranged at each position to be stretched of the sample; adjusting the heights of the first support plate (10) and the second support plate (7) so that all the clamps (11) are positioned on the same horizontal plane, and the connecting rod (5) in each uniaxial stretching device is parallel to the test bed (12);
2) determining the stretching amount of the sample, adjusting the position of a first fastening screw (4) in each uniaxial stretching device according to the stretching amount, and fixing the sample by a clamp (11);
3) the method comprises the steps of setting a program of a motor (1), enabling the motor to move completely synchronously, enabling the motor (1) to drive a turntable (3) to rotate through a coupler (2), converting the rotary motion of the turntable (3) into periodic linear motion through a connecting rod (5), and driving a sliding block (8) to drive a clamp (11) to reciprocate on a guide rail (9), so that the tested sample is stretched.
8. The testing method of the multi-axis tensile testing machine according to claim 7, wherein the tensile frequency of the jig (11) to the sample to be tested is changed by adjusting the rotation speed of the motor (1).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110969295.3A CN113551980A (en) | 2021-08-23 | 2021-08-23 | Multi-shaft type tensile test testing machine and testing method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110969295.3A CN113551980A (en) | 2021-08-23 | 2021-08-23 | Multi-shaft type tensile test testing machine and testing method |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN113551980A true CN113551980A (en) | 2021-10-26 |
Family
ID=78105928
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110969295.3A Withdrawn CN113551980A (en) | 2021-08-23 | 2021-08-23 | Multi-shaft type tensile test testing machine and testing method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113551980A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113933163A (en) * | 2021-11-05 | 2022-01-14 | 湖南贝恩叮当猫婴童用品有限公司 | Paper diaper quality detection device and detection method thereof |
| CN115505690A (en) * | 2022-10-25 | 2022-12-23 | 华北电力大学 | Tension device for temperature-magnetic-vibration composite aging |
| CN116609391A (en) * | 2023-06-19 | 2023-08-18 | 哈尔滨学院 | Polymer material electrical property testing device |
-
2021
- 2021-08-23 CN CN202110969295.3A patent/CN113551980A/en not_active Withdrawn
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113933163A (en) * | 2021-11-05 | 2022-01-14 | 湖南贝恩叮当猫婴童用品有限公司 | Paper diaper quality detection device and detection method thereof |
| CN113933163B (en) * | 2021-11-05 | 2024-05-24 | 湖南贝恩叮当猫婴童用品有限公司 | Paper diaper quality detection device and detection method thereof |
| CN115505690A (en) * | 2022-10-25 | 2022-12-23 | 华北电力大学 | Tension device for temperature-magnetic-vibration composite aging |
| CN116609391A (en) * | 2023-06-19 | 2023-08-18 | 哈尔滨学院 | Polymer material electrical property testing device |
| CN116609391B (en) * | 2023-06-19 | 2023-11-24 | 哈尔滨学院 | Polymer material electrical property testing device |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN113551980A (en) | Multi-shaft type tensile test testing machine and testing method | |
| CN111751217B (en) | Horizontal concrete uniaxial tension test device and application method thereof | |
| CN105181481A (en) | Three-point bending fatigue testing machine | |
| CN112781978B (en) | In-situ tester for micromechanics property of variable-angle biaxial stretching and thermal field coupling material | |
| CN112525478A (en) | Electric adjustment plane cascade experimental system | |
| CN108267372A (en) | Biaxial stretch-formed mechanics performance testing apparatus and micro mechanical property test equipment in situ | |
| CN204666454U (en) | A kind of fretting fatigue testing machine of contact load real-time, tunable | |
| CN117388687A (en) | Testing device and method for miniature linear piezoelectric motor | |
| CN108414355B (en) | Film stretching and loading unit with position locking function | |
| CN202693429U (en) | Material mechanical property testing platform for small sample in stretching and bending combined loading mode | |
| CN208547548U (en) | A kind of flexible wire reverse torsion machine | |
| CN208887878U (en) | A kind of vibration excitor test table adjusted based on worm gear mechanism | |
| CN219391606U (en) | Material tensile mechanical test equipment | |
| CN213580010U (en) | Electric adjustment plane cascade experimental system | |
| JP2016223776A (en) | Characteristics testing device of viscoelastic body | |
| CN204405428U (en) | A kind of Sample location assembly of dynamic thermomechanical analysis apparatus double cantilever beam fixture | |
| CN211147902U (en) | Brush pressure testing device | |
| CN215677565U (en) | Motor load testing device | |
| CN212932213U (en) | Tensile strength test equipment is used in rubber sleeve production | |
| CN218726063U (en) | Biaxial stretching mechanical property test device | |
| CN217966737U (en) | DMA double cantilever beam clamp positioning device | |
| CN221261027U (en) | Bearing speed measuring device | |
| CN216682072U (en) | Numerical control double-shaft rotary table precision adjusting structure | |
| CN213240273U (en) | Electric probe seat for testing | |
| CN219038708U (en) | Material hardness detection testing machine |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| WW01 | Invention patent application withdrawn after publication | ||
| WW01 | Invention patent application withdrawn after publication |
Application publication date: 20211026 |