CN112067433B

CN112067433B - Auxiliary centering installation device for composite material track shear test

Info

Publication number: CN112067433B
Application number: CN202010853798.XA
Authority: CN
Inventors: 李磊; 王彬文; 程鹏飞; 宋贵宾; 杨梦粤; 许飞
Original assignee: AVIC Aircraft Strength Research Institute
Current assignee: AVIC Aircraft Strength Research Institute
Priority date: 2020-08-24
Filing date: 2020-08-24
Publication date: 2023-09-22
Anticipated expiration: 2040-08-24
Also published as: CN112067433A

Abstract

The application belongs to the field of material performance test, and relates to an auxiliary centering installation device for a composite material track shear test. The test fixture comprises a base (1), a rotating rod (3) and a V-shaped groove plate (5), wherein two coaxial mounting holes (41) are formed in the base (1) and are used for fixing a loading rod of the test fixture; the rotating rod (3) is arranged to be of a rotatable structure, the tail end of the rotating rod is provided with a V-shaped groove plate (5), the V-shaped groove plate (5) comprises two clamping claws (52), the clamping claws (52) just extend into the V-shaped notch of the test piece, and the connecting lines of the two clamping claws are coincident with the axis of the mounting hole (41), so that the coincidence of the test piece and the axis of the test clamp is realized. The application can conveniently realize the centering installation of the test fixture and the test piece, ensure the coincidence of the central axis of the V-shaped notch part of the test piece and the loading axis of the test machine, improve the centering of the test fixture and the test piece, reduce human errors and improve the precision of test results.

Description

Auxiliary centering installation device for composite material track shear test

Technical Field

The application belongs to the field of material performance testing, and particularly relates to an auxiliary centering installation device for a composite material track shear test.

Background

The V-notch rail shear test is the most dominant and common test method for measuring the shear performance of composite multi-directional laminates at present, and corresponds to the test standard ASTM D7078. The main application range of the test is as follows: a) The laminated board only consists of unidirectional fiber layers, and the laying direction of the laminated board is parallel or perpendicular to the clamp rails; b) The 0 layers of the balanced symmetrical laminated plates are parallel or perpendicular to the clamp rails; c) The laminated board consists of single-layer fibers of fabric, braiding or fiber cloth; d) The short fiber reinforced composite material is randomly distributed. The measured test data can be used for production quality control and material specification preparation, and can also be used for structural design.

Fig. 1 shows a schematic view of a V-shaped rail shear test, where the test fixture 100 includes two test pieces, each having a loading rod 101 and a clamping portion 102, and the clamping portion 102 is used for clamping a test piece 200, a V-shaped notch is formed in the middle of the test piece 200, and when the test piece is tested, two identical left and right clamping portions clamp the V-shaped notch test piece in the middle and apply a tensile load on the test machine, a shearing force is generated in the test piece and the notch is broken.

For accurate and reliable V-track shear test data, one of the key requirements is that the V-notch test piece has to have its V-notch cross-section axis coincident with the loading axis, which requires that the two loading rod axes and V-notch cross-section axes in fig. 1 have to be coincident. It can be understood that the upper end of the test piece 200 is fixed by the screw of the clamping portion of the test jig 100 on the left side and the lower end of the test piece 200 is fixed by the screw of the clamping portion of the test jig 100 on the right side, but which position of the screw to clamp the upper or lower portion of the test piece specifically cannot be precisely determined, and thus it cannot be ensured that the ideal clamping state as shown in fig. 1 is achieved.

The existing test fixture mainly depends on two positioning blocks (other auxiliary tools) matched with the V-shaped notch to ensure that the axes of the two loading rods and the central axis of the V-shaped notch are positioned on the section of the V-shaped notch of the test piece along the graph in fig. 1, but the coincidence of three lines cannot be ensured, namely the state in fig. 1 is met, but under the top view in fig. 1 (the top view of the test fixture 100 can refer to fig. 9 a), the central axis of the test piece is not coincident with the central axis of the fixture. The test personnel generally ensure that the three lines coincide by measuring and adjusting the position of the test piece on a vernier caliper. This method is very cumbersome and has a relatively large accumulated error due to the need to measure the distance between the plurality of parts and locations and the test piece, and the mounting accuracy is poor. When the axes of the two loading rods are not coincident with the axis of the V-shaped notch section of the test piece, out-of-plane bending and torsional deformation can occur in the test process, the V-shaped notch section of the test piece cannot present a pure shear stress state, and the test result can be greatly influenced.

Disclosure of Invention

In order to solve the technical problems, the application provides an auxiliary centering installation device for a composite material track shear test, which is used for helping a test clamp to clamp a test piece and meeting the three-line superposition described in the background art.

The auxiliary centering installation device of the application comprises:

the base is provided with a top surface, the top surface comprises a notch with a groove in the middle and fixing tables positioned at two sides of the notch, a cylindrical lock catch is arranged on any fixing table, the cylindrical lock catch and the fixing table form a mounting hole with a clamping part for clamping the test clamp in an adapting mode, the axes of the two mounting holes coincide in a first direction, and when the clamping part of the test clamp is fixed in the mounting hole, the clamping part of the test clamp is positioned at the notch;

the rotating rod 3 comprises a rotating end and a mounting end relative to the rotating end, the rotating end is rotatably mounted on the base, the mounting end is of a plate surface structure and is provided with a through hole, and the rotating rod is configured to be driven to a limit position when rotating around the rotating end on a plane where the first direction is located, and the limit position is right above the notch;

the V-shaped groove plate comprises a main body part and two arms which extend along the plate surface direction and shrink inwards at the end parts to form clamping claws, the clamping claws just extend into V-shaped notch of a test piece, the main body part is provided with a sliding rail, the sliding rail can extend into a through hole of the installation end of a rotating rod and move in a second direction perpendicular to the first direction in the through hole so that the V-shaped groove plate is attached to or far away from the plate surface of the installation end of the rotating rod, when the rotating rod drives the V-shaped groove plate to move to the limit position, and when the V-shaped groove plate is attached to the installation end of the rotating rod, the connecting lines of the two clamping claws are overlapped with the axis of the installation hole in the first direction.

Preferably, the rotating end of the rotating rod is hinged to a stand column, and the stand column is fixed on the base.

Preferably, the upright is mounted on the base in a threaded connection.

Preferably, the cylinder fixing table comprises a first groove with a semicircular section, the cylinder lock catch is provided with a hinged end and a fixed end, and a pressing block located between the hinged end and the fixed end, the pressing block is provided with a second groove with a semicircular section, the hinged end of the cylinder lock catch is hinged to one side of the first groove, the fixed end of the cylinder lock catch can be locked to the other side of the first groove, and the first groove and the second groove jointly form the mounting hole.

Preferably, the fixed end of the cylindrical lock catch is fixed on the fixed table through a screw.

Preferably, the sliding rail of the V-shaped groove plate is provided with a threaded hole, and the sliding rail is driven to move in the through hole by a screw.

Preferably, the through holes are bar-shaped holes.

Preferably, the flat plate lock comprises a hinge end and a lock end, wherein the hinge end is hinged on one arm of the V-shaped groove plate, and the lock end can be fixed on the other arm of the V-shaped groove plate.

The application can conveniently realize the centering installation of each part of the test fixture and the centering installation of the test piece in the test fixture, ensure the coincidence of the central axis of the V-shaped notch part of the test piece and the loading axis of the test machine, improve the centering of the test fixture and the test piece installation, reduce the human error and improve the precision of the test result.

Drawings

FIG. 1 is a schematic diagram of the mounting relationship of a test fixture to a test piece.

FIG. 2 is a structural perspective view of a preferred embodiment of an auxiliary centering device for a composite track shear test of the present application.

Fig. 3 is a front view of the embodiment of the application shown in fig. 2.

Fig. 4 is a schematic view of the base structure of the embodiment of fig. 2 according to the present application.

Fig. 5 is a schematic view of the structure of the turning lever according to the embodiment of fig. 2.

Fig. 6 is a schematic view of the V-groove plate structure of the embodiment of fig. 2 according to the present application.

Figure 7 is a schematic view of a cross-section of a V-groove plate A-A of the embodiment of the application shown in figure 6.

Fig. 8 is a schematic view of the cylindrical lock catch according to the embodiment of fig. 2.

Fig. 9a-9d are schematic views of the auxiliary centering and mounting device for the composite material track shear test according to the application in the sequential use.

The device comprises a 100-test clamp, a 200-test piece, a 101-loading rod and a 102-clamping part, wherein the test piece is fixedly connected with the 100-test clamp;

1-base, 11-notch, 12-fixed platform, 2-stand, 3-dwang 3, 31-through hole, 4-cylinder hasp, 41-mounting hole, 42-briquetting, 43-screw, 44-pillar, 45-round pin axle, 5-V type recess board, 51-arm, 52-jack catch, 53-slide rail, 54-screw, 6-flat hasp.

Detailed Description

In order to make the objects, technical solutions and advantages of the present application become more apparent, the technical solutions in the embodiments of the present application will be described in more detail with reference to the accompanying drawings in the embodiments of the present application. In the drawings, the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The described embodiments are some, but not all, embodiments of the application. The embodiments described below by referring to the drawings are exemplary and intended to illustrate the present application and should not be construed as limiting the application. All other embodiments, based on the embodiments of the application, which are apparent to those of ordinary skill in the art without inventive faculty, are intended to be within the scope of the application. Embodiments of the present application will be described in detail below with reference to the accompanying drawings.

The application provides an auxiliary centering installation device for a composite material track shear test, which mainly comprises a base 1, a rotating rod 3 rotatably arranged on the base 1 and a V-shaped groove plate 5 capable of sliding on the rotating rod 3, as shown in fig. 2-8.

Fig. 4 shows a schematic structural diagram of the base 1, where the base 1 has a top surface, the top surface includes a slot 11 with a slot in the middle, and fixing tables 12 located at two sides of the slot, each of the fixing tables 12 has a cylindrical lock 4, the cylindrical lock 4 and the fixing table 12 form a mounting hole 41 with a clamping portion 102 adapted to clamp a test fixture, axes of the two mounting holes 41 coincide in a first direction, and when the clamping portion 102 of the test fixture is fixed in the mounting hole 41, the clamping portion 102 of the test fixture is located at the slot 11.

In this embodiment, the upper portion of the base 1 has two rectangular blocks with a protrusion, and the middle of each rectangular block is hollowed out according to the shape of the V-shaped notch rail shearing clamp shown in fig. 1, and the left and right parts of the V-shaped rail shearing test clamp can be respectively placed therein. The centers of the upper surfaces of the left rectangular block and the right rectangular block are respectively provided with a semi-cylindrical groove, and the axes of the two semi-cylindrical grooves are coincident. The two loading rods 101 of the V-shaped rail shear test fixture can be just completely fit into the two semi-cylindrical grooves. When the two loading rods 101 of the V-shaped rail shear test fixture are placed in the two semi-cylindrical grooves and fully attached, the axes of the two loading rods 101 of the V-shaped rail shear test fixture are also coincident. The upper surfaces of the left and right rectangular blocks are also provided with a plurality of threaded holes for installing the cylindrical lock catch shown in fig. 8. When the V-shaped rail shear test fixture is used, the clamping rod of the V-shaped rail shear test fixture is placed in the semicircular column groove on the base, and then the cylindrical lock catch is locked, so that the clamping rod and the test fixture can be fixed on the base. The cylindrical lock is opened and the loading rod 101 together with the whole test fixture can be unloaded from the base.

The structure of the rotating rod 3 is shown in fig. 5, and the rotating rod comprises a rotating end and a mounting end opposite to the rotating end, wherein the rotating end is rotatably mounted on the base 1, the mounting end is of a plate surface structure, a through hole 31 is formed in the mounting end, and the rotating rod 3 is configured to be driven to a limit position when rotating around the rotating end on a plane where the first direction is located, and the limit position is right above the notch 11.

The function of this part is to mount a V-groove plate with guide rails (a test piece can be mounted in a V-groove plate with guide rails) thereon, and when it is rotated to the extreme position shown in fig. 3, the test piece mounted thereon is located just in the center position of the V-rail shear test jig, and the V-notch cross-section axis of the V-notch test piece is now just coincident with the two semicircular column groove axes above the base. With continued reference to fig. 5, the center of the right side plate of the rotating lever has a slot-shaped through hole in which the slide rail 53 of the V-shaped slot plate 5 of fig. 7 can move.

The V-shaped groove plate 5 has a structure as shown in fig. 6-7, and comprises a main body portion, and two arms 51 extending in the plate surface direction of the main body portion, wherein the two arms 51 are contracted inwards in the end portions to form a claw 52, the claw 52 just stretches into the V-shaped notch of the test piece 200, the main body portion is provided with a sliding rail 53, the sliding rail 53 can stretch into the through hole 31 of the mounting end of the rotating rod 3, and move in the through hole 31 along a second direction perpendicular to the first direction, so that the V-shaped groove plate 5 is attached to or away from the plate surface of the mounting end of the rotating rod 3, and when the rotating rod 3 drives the V-shaped groove plate 5 to move to the limit position, and the connecting line of the two claws coincides with the axis of the mounting hole 41 in the first direction.

In this embodiment, with respect to fig. 3, the first direction is a left-right direction, the second direction is a direction perpendicular to the paper surface, the short slide rail 53 on the back surface of the V-shaped groove plate 5 can be completely fit into the slot on the upper surface of the rotating rod, and the V-shaped groove plate 5 can move along the second direction. The rail 53 has a threaded hole in the middle, through which a V-groove plate 5 with a guide rail can be fastened to the test piece-mounted rotating lever 3 by means of a screw 54 of the type of a plum blossom. When the V-groove plate 5 is required to be fixed on the rotating rod, the screw 54 on the back can be tightened to fix it.

When the auxiliary centering installation device is used, the V-shaped groove plate with the guide rail is fixed on the rotating rod by the plum blossom screw, then the test piece is placed in the middle of the V-shaped groove plate with the guide rail, and the flat plate lock catch arranged on the V-shaped groove plate with the guide rail is closed, so that the test piece can be completely fixed in the V-shaped groove plate with the guide rail. The quincuncial screws on the back sides of the flat lock catches and the V-shaped groove plates with the guide rails are loosened, and then the V-shaped groove plates with the guide rails are pushed to the forefront (along the second direction), so that the test piece can be separated from the V-shaped groove plates with the guide rails.

In some alternative embodiments, the rotating end of the rotating rod 3 is hinged on a column 2, and the column 2 is fixed on the base 1. The rotating rod 3 is pinned on the upright 2 by a cylindrical pin and can rotate 180 degrees around a round hole on the upright (the maximum rotating position of the rotating rod on the left side of the upright is shown in fig. 2 or 3).

In some alternative embodiments, the upright 2 is screwed to the base 1, or in alternative embodiments, may be fixed by welding, etc., but it should be noted that the height of the upright 2 needs to be set in advance, so that, in the state shown in fig. 3, the line connecting the two claws 52 coincides with the axis of the mounting hole 41 in the first direction.

In some alternative embodiments, the cylindrical fixing table 12 includes a first groove with a semicircular cross section, the cylindrical lock catch 4 has a hinged end and a fixed end, and a pressing block 42 located between the hinged end and the fixed end, the pressing block 42 has a second groove with a semicircular cross section, the hinged end of the cylindrical lock catch 4 is hinged on one side of the first groove, the fixed end of the cylindrical lock catch 4 can be locked on the other side of the first groove, and the first groove and the second groove together form the mounting hole 41.

In some alternative embodiments, the fixed end of the cylindrical lock is fixed to the fixed base 12 by a screw 43.

As shown in fig. 8, the hinged end of the cylindrical lock catch 4 mainly comprises a pillar 44 and a pin 45, the pillar 44 is fixed on the fixed table 12 of the base 1, and the pressing block 42 is rotatably connected to the top end of the pillar 44 through the pin 45, so that the pressing block 42 forms a structure rotating around the pin 45, and after the pressing block 42 rotates to the position shown in fig. 8, the pressing block 42 and the semicircular groove on the fixed table 12 form the mounting hole 41 together.

The flat lock 6 is similar to the cylindrical lock 4 in structure, and the flat lock 6 includes a hinge end and a locking end, wherein the hinge end is hinged on one arm 51 of the V-shaped groove plate 5, and the locking end can be fixed on the other arm 51 of the V-shaped groove plate 5. It will be appreciated that the flat plate latch 6 is located on the side of the V-groove plate 5 facing away from the rotating lever 3, and when the test piece is mounted on the V-groove plate 5, one side of the test piece is pressed against the plate surface of the rotating lever 3, and the other side of the test piece is latched by the flat plate latch 6.

In some alternative embodiments, the sliding rail 53 of the V-shaped groove plate 5 has a threaded hole, and the sliding rail 53 is driven to move in the through hole 31 by a screw 54.

In some alternative embodiments, the through holes 31 are bar-shaped holes. It will be appreciated that the bar-shaped aperture ensures that the V-shaped fluted plate can move in a second direction (perpendicular to the plane of the paper) but cannot rotate or move in other directions.

The method of using the auxiliary centering installation device for the composite material track shear test is shown in fig. 9a-9 d:

a) Before the V-shaped track test fixture and test installation are carried out, the auxiliary centering installation device for the composite material track shear test is firstly opened: the two cylindrical catches and the flat catch are opened and the rotating rod is rotated to a position which does not interfere with the test fixture. And simultaneously, the quincuncial screw on the back of the rotating rod is twisted tightly, so that the V-shaped groove plate with the guide rail is completely fixed on the rotating rod.

b) Half of the V-notch test fixture is placed onto the auxiliary centering fixture base such that the clamping bar of the test fixture flexes to fit the semi-cylindrical groove on the base and locks the left cylindrical lock 4, securing the part of the test fixture to the auxiliary centering fixture as shown in fig. 9 a.

c) The test piece is arranged on the V-shaped groove plate with the guide rail and is locked with the upper flat plate lock catch 6, so that the test piece is fixed. The turning lever is then turned to be located at the left-hand limit position. At this time, the test piece is just positioned in the middle of the V-shaped notch rail shear test fixture to be installed, and the cross section axis of the V-shaped notch of the test piece is just coincident with the axis of the clamping rod of the half of the test fixture which is already installed. And then the bolts at the two sides of the rail shear test clamp are tightened to completely fix the test piece. A schematic diagram of this state is shown in fig. 9b.

d) After the test piece is completely fixed on a half V-shaped track test fixture, the flat plate lock catch is opened, and the quincuncial screw on the back of the rotating rod is loosened, so that the V-shaped groove plate with the guide rail is separated from the rotating rod. The V-groove plate with guide rail is pushed to the forefront so as to be separated from the test piece. The rotating rod 3 is then rotated, so that the rotating rod is separated from the test piece. A schematic view of the separation of the rotating lever from the test piece is shown in FIG. 9c.

e) The other half of the test fixture is placed on the base of the auxiliary centering installation device, so that the clamping rod of the test fixture is bent to be attached to the semi-cylindrical groove on the base, and the right-side cylindrical lock catch 4 is locked, so that the test fixture is fixed on the auxiliary centering installation device. And then the screws on the test clamp are screwed tightly, so that the whole rail shear test clamp and the test piece are installed, the test piece is positioned in the center of the test clamp, and the clamping rod axis of the test clamp is aligned with the V-shaped notch cross section axis of the test piece in a bending way. A schematic diagram of this state is shown in fig. 9d.

f) After the test fixture and the test piece are fixed together through the screw on the test fixture, the cylindrical lock catches 4 on two sides can be opened, the test piece and the test fixture are taken down, and a formal V-shaped rail shearing test is performed.

Compared with the prior art, the application has the following advantages: the coincidence of two loading rods and the cross section axis of the V-shaped notch of the test piece during the installation of the V-shaped track shear test is guaranteed through the structural form, and is not guaranteed by artificial measurement and adjustment, so that the method is convenient, quick and high in precision.

Claims

1. Auxiliary centering installation device for combined material track shear test is with auxiliary centering installation device for auxiliary test anchor clamps (100) centre gripping test piece (200), test anchor clamps (100) are including loading pole (101) and clamping part (102), clamping part (102) can press from both sides tightly test piece (200), its characterized in that, auxiliary centering installation device includes:

the base (1) is provided with a top surface, the top surface comprises a notch (11) with a groove in the middle and fixing tables (12) positioned at two sides of the notch, a cylindrical lock catch (4) is arranged on any fixing table (12), the cylindrical lock catch (4) and the fixing table (12) form a mounting hole (41) with a loading rod (101) which is matched with and clamps a test clamp, the axes of the two mounting holes (41) are coincident in a first direction, and when the loading rod (101) of the test clamp is fixed in the mounting hole (41), a clamping part (102) of the test clamp is positioned at the notch (11);

the rotating rod (3) comprises a rotating end and a mounting end relative to the rotating end, the rotating end is rotatably mounted on the base (1), the mounting end is of a plate surface structure and is provided with a through hole (31), the rotating rod (3) is configured to be driven to a limit position when rotating around the rotating end on a plane where the first direction is located, and the limit position is right above the notch (11);

the V-shaped groove plate (5) comprises a main body part and two arms (51) extending along the plate surface direction of the main body part, wherein the two arms (51) are contracted inwards in the end parts to form a claw (52), the claw (52) just stretches into a V-shaped notch of the test piece (200), the main body part is provided with a sliding rail (53), the sliding rail (53) can stretch into a through hole (31) of the mounting end of the rotating rod (3) and move in a second direction perpendicular to the first direction in the through hole (31), so that the V-shaped groove plate (5) is attached to or far away from the plate surface of the mounting end of the rotating rod (3), and when the rotating rod (3) drives the V-shaped groove plate (5) to move to the limit position, and when the V-shaped groove plate (5) is attached to the mounting end of the rotating rod (3), the connecting lines of the two claws coincide with the axis of the mounting hole (41) in the first direction;

the rotating end of the rotating rod (3) is hinged to a stand column (2), and the stand column (2) is fixed on the base (1);

the fixing table (12) comprises a first groove with a semicircular section, the cylindrical lock catch (4) is provided with a hinged end and a fixed end, and a pressing block (42) positioned between the hinged end and the fixed end, the pressing block (42) is provided with a second groove with a semicircular section, the hinged end of the cylindrical lock catch (4) is hinged to one side of the first groove, the fixed end of the cylindrical lock catch (4) can be locked to the other side of the first groove, and the first groove and the second groove jointly form the mounting hole (41);

the novel V-shaped groove plate comprises a V-shaped groove plate body, and is characterized by further comprising a flat lock catch (6), wherein the flat lock catch (6) comprises a hinged end and a lock catch end, the hinged end is hinged to one arm (51) of the V-shaped groove plate (5), and the lock catch end can be fixed to the other arm (51) of the V-shaped groove plate (5).

2. Auxiliary centering installation device for a composite material rail shear test according to claim 1, characterized in that the upright (2) is screw-mounted on the base (1).

3. Auxiliary centering and mounting device for shear test of composite material rails according to claim 1, characterized in that the fixed end of the cylindrical lock catch is fixed on the fixed table (12) by means of a screw (43).

4. Auxiliary centering installation device for shear test of composite material rail according to claim 1, characterized in that the slide rail (53) of the V-shaped groove plate (5) is provided with a threaded hole, and the slide rail (53) is driven to move in the through hole (31) by a screw (54).

5. Auxiliary centering and mounting device for shear test of composite material rails according to claim 1 or 4, characterized in that the through holes (31) are bar-shaped holes.