CN111487130A

CN111487130A - Novel centre gripping test equipment of exempting from of aquogel tensile test

Info

Publication number: CN111487130A
Application number: CN202010299378.1A
Authority: CN
Inventors: 雷冬; 黄弘毅; 荆晓晖
Original assignee: Hohai University HHU
Current assignee: Hohai University HHU
Priority date: 2020-04-16
Filing date: 2020-04-16
Publication date: 2020-08-04

Abstract

The invention discloses novel clamping-free test equipment for hydrogel tensile test, which comprises clamping plates and clamps, wherein the clamps are provided with U-shaped grooves for accommodating hydrogel tensile pieces, the number of the clamping plates is 2, the clamping plates are symmetrically arranged on two sides of the clamps, the cross sectional area of each clamping plate is larger than that of each U-shaped groove, the 2 clamping plates are buckled on the clamps through locking devices, and the locking devices are used for fixing the hydrogel tensile pieces between the clamping plates and the clamps. The device carries out tensile test on the hydrogel under the condition that overlarge clamping pressure is not applied to the thickness direction of the hydrogel tensile piece, replaces the method that the conventional chuck directly clamps the surface of the sample, avoids the damage of clamping force on the sample, enables the sample not to be easily damaged, and is convenient to disassemble.

Description

Novel centre gripping test equipment of exempting from of aquogel tensile test

Technical Field

The invention relates to the field of hydrogel tensile experimental equipment, in particular to novel clamping-free testing equipment for hydrogel tensile testing.

Background

The hydrogel is a gel taking water as a dispersion medium, is a high-water-absorption and high-water-retention material, and is widely applied to the fields of medicines, biology, engineering and the like. Generally, a tensile testing machine is adopted to carry out tensile test on a standard part of a material when the mechanical property of the material is tested, the hydrogel is soft and fragile, the elastic modulus is not as large as that of rubber and plastic, the deformation in the testing process is large, when the mechanical property is tested by the tensile test, tooth-shaped protrusions are arranged on the surface of a chuck of clamping equipment of the conventional tensile testing machine, the clamping force is large, large clamping force is generated in the thickness direction of the hydrogel, the sample is easy to damage in the tensile process, the data obtained in the experimental process is inaccurate, the data discrete degree is high, and the influence on scientific research work is great.

CN208999202U discloses an auxiliary clamp for hydrogel tensile test, which comprises a fastening piece, a support plate, two clamping plates and two clamps, wherein the support plate is provided with a support boss, the two clamps are arranged on the support plate and positioned at two sides of the support boss, the upper end surfaces of the support boss are flush with the upper end surfaces of the two clamps, gaskets are arranged on the upper end surfaces of the two clamps, the two clamping plates are arranged on the upper end surfaces of the gaskets, the fastening piece comprises an upper fastening piece and a lower fastening piece, the upper fastening piece is arranged on the upper end surface of the splicing part of the two clamping plates, and the lower fastening piece is arranged on the lower end surface of the splicing part of the two. The device avoids the chuck of the universal tensile testing machine from crushing and shearing the standard hydrogel tensile part through the cooperation of the upper clamp and the lower clamp, so that the accuracy of test data is ensured, but the device is complex to assemble and influences the test efficiency.

Disclosure of Invention

The invention aims to provide novel clamping-free test equipment for hydrogel tensile test, the device is convenient to assemble, excessive pressure in the thickness direction of the hydrogel tensile piece can be avoided in the process of carrying out uniaxial tensile test on the hydrogel tensile piece, the position of the hydrogel tensile piece is fixed, experimental data fluctuation caused by displacement of the hydrogel tensile piece in the test process is prevented, the disassembly is simple and convenient, and the test efficiency is improved.

In order to achieve the purpose, the invention adopts the technical scheme that:

the utility model provides a centre gripping test equipment is exempted from to novel of aquogel tensile test, includes splint and anchor clamps, be equipped with the U type groove of the tensile piece of holding aquogel on the anchor clamps, splint are 2 and the symmetry sets up the both sides of anchor clamps, the cross-sectional area of splint is greater than the cross-sectional area in U type groove, 2 splint pass through the locking device lock and are in on the anchor clamps, locking device is used for fixing the tensile piece of aquogel between splint and the anchor clamps.

When the device is used, a novel cutter is adopted to cut a synthesized rectangular film-shaped hydrogel sample through a sheet punching machine to obtain the hydrogel tensile piece, the U-shaped groove of the clamp is matched with the shape of the hydrogel tensile piece, the hydrogel tensile piece is placed into the U-shaped groove, a clamping plate is covered, the hydrogel tensile piece and the clamping plate are fixed, the clamp and the clamping plate are fixed through a locking device, and the assembled testing device is fixed with a tensile testing machine, so that the tensile testing can be started. In the stretching process, a locking device applies axial force to the hydrogel stretching piece to generate deformation; and meanwhile, the clamping plate is fixed on the clamp by the locking device, the sample is wrapped in the clamping plate, so that the clamping plate is prevented from displacing in the stretching process, and the sample can be taken out by taking down the locking device and the clamping plate after the test is finished. The locking device can be composed of a T-shaped bolt and a nut which are commonly used in the prior art, or a screw rod and two nuts.

Further, locking device includes bolt and nut, the bolt runs through 2 splint, and the both ends of aquogel tensile piece are equipped with the first through-hole of bolt external diameter looks adaptation, the nut is used for the locking the bolt.

Further, the locking device is composed of a T-shaped bolt and a nut.

Furthermore, a second through hole is formed in the center of the clamping plate, a plurality of third through holes are further formed in the clamping plate, and a fourth through hole corresponding to the third through holes is further formed in the clamp.

Further, a plurality of the third through holes are circumferentially arranged around the second through hole.

Further, the splint and the clamp have a hardness greater than the hydrogel tension member. The clamping plate and the clamp can be made of steel or aluminum alloy.

Furthermore, bosses are arranged on the outer sides of the U-shaped grooves on the upper end face and the lower end face of the clamp, and the clamping plates are located between the adjacent bosses.

Further, a novel cut-off knife comprises a first cut-off knife and a second cut-off knife movably arranged in the first cut-off knife, wherein the first cut-off knife is a dumbbell type sample cut-off knife, and the structure of the dumbbell type sample cut-off knife is the prior art, for example, the structure of the dumbbell type sample cut-off knife is not provided with a bottom cover and a top cover in patent CN202878416U, so that the external structure of the novel cut-off knife is not repeated; u-shaped baffles are arranged at two ends of the bottom of the first cut-off knife, and inserting blocks are symmetrically arranged on the inner wall of the first cut-off knife and above each U-shaped baffle; the bottom structure of the second cut-off knife is dumbbell-shaped, hollow cylinder protrusions are arranged at two ends of the bottom of the second cut-off knife, slots are formed in the positions, corresponding to the insertion blocks, of the second cut-off knife, and the second cut-off knife can be placed into the first cut-off knife to form a cubic structure. The dumbbell type sample cut-off knife among the prior art can not prepare in this application the aquogel tensile member, and this application improves the structure of novel cut-off knife.

Above-mentioned novel cut-off knife is when using, puts the bottom of second cut-off knife in the top of the U type baffle of first cut-off knife, the cylinder is protruding to coincide with the cavity in the U type baffle mutually, and inserted block and slot closely laminate, have the frictional force of certain intensity, prevent that the second cut-off knife from falling down from first cut-off knife, obtain novel cut-off knife, prepare the aquogel tensile member in this application.

Compared with the prior art, the invention has the beneficial effects that:

this device equipment is convenient, through carrying out tensile test to the tensile piece of aquogel under the condition of not exerting too big clamping pressure to the tensile piece thickness direction of aquogel, replaces the method on the direct centre gripping sample surface of current chuck, avoids the destruction of clamping-force to the sample, makes the indestructible of sample, and dismantles the convenience, improves efficiency of software testing.

Drawings

Fig. 1 is a perspective view of a splint 1 according to the present invention according to embodiment 1;

fig. 2 is a perspective view of the inventive clamp 2 according to example 1;

FIG. 3 is a top view of a hydrogel tensioning member 4 of the present invention according to example 1;

FIG. 4 is a top view of the present invention according to example 1;

fig. 5 is a perspective view of the first cutter 9 of the present invention according to embodiment 1;

fig. 6 is a perspective view of a second cutter 10 of the present invention according to embodiment 1;

fig. 7 is a perspective view of the novel cutter of the present invention according to example 1;

in the figure: 1. a splint; 2. a clamp; 3. a U-shaped groove; 4. a hydrogel tensile member; 5. a first through hole; 6. a second through hole; 7. a third through hole; 8. a fourth via hole; 9. a first cutter; 10. a second cutter; 11. a U-shaped baffle plate; 12. inserting a block; 13. the cylinder is convex; 14. and (4) a slot.

Detailed Description

The technical solutions of the present invention will be described clearly and completely with reference to the accompanying drawings, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Example 1

As shown in fig. 1-4, a novel clamping-free test device for hydrogel tensile test comprises a clamp plate 1 and clamps 2, wherein each clamp 2 is provided with a U-shaped groove 3 for accommodating a hydrogel tensile member 4, the clamp plate 1 is 2 and symmetrically arranged on two sides of the

clamp

2, 2 the clamp 2 is used for placing the hydrogel tensile member 4, the cross-sectional area of the clamp plate 1 is larger than that of the U-shaped groove 3, the cross-sectional area of the clamp plate 1 is smaller than that of the clamp 2, so that the clamp plate 1 covers the

U-shaped groove

3, 2 clamp plates 1 are buckled on the clamp 2 through locking devices, the number of the clamp plate 1 is 4, and the locking devices are used for fixing the hydrogel tensile member between the clamp plate 1 and the clamp 2. The locking device comprises T-shaped bolts and nuts, the bolts penetrate through the 2 clamping plates 1, first through holes 5 matched with the outer diameters of the bolts are formed in the two ends of the hydrogel stretching piece 4, the nuts are used for locking the bolts, a second through hole 6 is formed in the center of each clamping plate 1, a locking device is arranged between each clamping plate 1 and the corresponding clamp 2, and each locking device is composed of the T-shaped bolts and the nuts. Bosses are arranged on the outer sides of the U-shaped grooves 3 on the upper end face and the lower end face of the clamp 2, and the clamping plates 1 are located between the adjacent bosses.

The center of splint 1 is equipped with second through-hole 6, still be equipped with a plurality of third through-holes 7 on splint 1, still be equipped with on anchor clamps 2 with the corresponding fourth through-hole 8 of third through-hole 7, fourth through-hole 8 is kept away from the boss, preferably, it is a plurality of third through-hole 7 winds second through-hole 6 is the circumference setting, the material of splint and anchor clamps is steel or aluminum alloy.

The working principle of the device is as follows: adopt novel cut-off knife to tailor through the die-stamping machine to the rectangle film form aquogel sample that synthesizes out, obtain aquogel tension member 4, U type groove 3 and the 4 appearance phase-matchs of aquogel tension member of anchor clamps 2 will aquogel tension member 4 is put into U type inslot 3 covers splint 1, locking device passes first through-hole and second through-hole are right aquogel tension member and splint are fixed, and rethread locking device is right anchor clamps and splint are fixed, and the testing arrangement who will assemble again fixes with tensile testing machine, can begin to carry out tensile test. In the stretching process, a locking device applies axial force to the hydrogel stretching piece to generate deformation; meanwhile, the clamping plate is fixed on the clamp by the locking device, the sample is wrapped in the clamping plate, so that the sample is prevented from displacing in the stretching process, and the sample can be taken out by taking down the locking device and the clamping plate after the test is finished. The locking device may be comprised of a bolt and a nut as is commonly used in the art.

As shown in fig. 5-7, the novel cutter is composed of a first cutter 9 and a second cutter 10 movably disposed inside the first cutter 9, the first cutter 9 is a dumbbell-shaped sample cutter, and the structure of the dumbbell-shaped sample cutter is the prior art, for example, the structure of patent CN202878416U without a bottom cover and a top cover, so the external structure of the invention is not described again; the two ends of the bottom of the first cut-off knife 9 are respectively provided with a U-shaped baffle 11, and the inner wall of the first cut-off knife 9 and above each U-shaped baffle 11 are symmetrically provided with an insert block 12; the bottom structure of the second cut-off knife 10 is dumbbell-shaped, hollow cylindrical protrusions 13 are arranged at two ends of the bottom of the second cut-off knife 10, slots 14 are arranged in positions, corresponding to the insertion blocks 12, of the second cut-off knife 10, and the second cut-off knife 10 can be placed inside the first cut-off knife 9 to form a cubic structure. The dumbbell type sample cut-off knife among the prior art can not prepare in this application the aquogel tensile member, and this application improves the structure of novel cut-off knife.

Above-mentioned novel cut-off knife is when using, puts the bottom of second cut-off knife 10 in the top of the U type baffle 11 of first cut-off knife 9, the protruding 13 and the cavity department in the U type baffle 11 of cylinder coincide mutually, and inserted block 12 and slot 14 closely laminate, have the frictional force of certain intensity, prevent that second cut-off knife 10 from falling down from first cut-off knife 9, obtain novel cut-off knife, prepare the aquogel tensile member in this application.

Example 2

Example 2 differs from example 1 in that: the cross sectional area of the clamping plate 1 is equal to that of the clamping device 2, so that the clamping plate 1 covers the clamping device 2, and the clamping plate 1 is convenient to take down after the test is completed.

Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.

Claims

1. The utility model provides a centre gripping test equipment is exempted from to novel of aquogel tensile test, a serial communication port, including splint (1) and anchor clamps (2), be equipped with U type groove (3) of holding aquogel tensile piece (4) on anchor clamps (2), splint (1) are 2 and the symmetry sets up the both sides of anchor clamps (2), the cross-sectional area of splint (1) is greater than the cross-sectional area of U type groove (3), 2 splint (1) is in through the locking device lock on anchor clamps (2), locking device is used for fixing aquogel tensile piece between splint (1) and anchor clamps (2).

2. The novel clamping-free testing device for hydrogel tensile testing as claimed in claim 1, wherein the locking device comprises a bolt and a nut, the bolt penetrates through 2 clamping plates (1), and both ends of the hydrogel tensile member (4) are provided with first through holes (5) matched with the outer diameter of the bolt, and the nut is used for locking the bolt.

3. The novel clamping-free testing device for hydrogel tensile testing as claimed in claim 2, wherein the locking means is comprised of a T-bolt and a nut.

4. The novel clamping-free test device for the hydrogel tensile test is characterized in that a second through hole (6) is formed in the center of the clamping plate (1), a plurality of third through holes (7) are formed in the clamping plate (1), and a fourth through hole (8) corresponding to the third through hole (7) is formed in the clamp (2).

5. The novel clamping-free test device for hydrogel tensile test according to claim 4, wherein a plurality of the third through holes (7) are circumferentially arranged around the second through hole (6).

6. The novel clamp-free testing device for hydrogel tensile testing as claimed in claim 1, wherein the hardness of the clamping plate (1) and the clamp (2) is greater than the hardness of the hydrogel tensile member (4).

7. The novel clamping-free test device for the hydrogel tensile test is characterized in that bosses are arranged on the outer sides of the U-shaped grooves (3) of the upper end surface and the lower end surface of the clamp (2), and the clamping plates (1) are arranged between the adjacent bosses.

8. The novel cut-off knife is characterized by comprising a first cut-off knife (9) and a second cut-off knife (10) movably arranged in the first cut-off knife (9), wherein the first cut-off knife (9) is a dumbbell-shaped sample cut-off knife, two ends of the bottom of the first cut-off knife (9) are respectively provided with a U-shaped baffle (11), and inserting blocks (12) are symmetrically arranged on the inner wall of the first cut-off knife (9) and above each U-shaped baffle (11); the bottom structure of the second cut-off knife (10) is dumbbell-shaped, hollow cylindrical protrusions (13) are arranged at two ends of the bottom of the second cut-off knife (10), and slots (14) are arranged in positions, corresponding to the insertion blocks (12), on the second cut-off knife (10).