CN111077028A - Impact loading test device - Google Patents
Impact loading test device Download PDFInfo
- Publication number
- CN111077028A CN111077028A CN201911074716.5A CN201911074716A CN111077028A CN 111077028 A CN111077028 A CN 111077028A CN 201911074716 A CN201911074716 A CN 201911074716A CN 111077028 A CN111077028 A CN 111077028A
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- guide rail
- impact
- baffle
- fixing
- seat
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- 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
- G01N3/30—Investigating strength properties of solid materials by application of mechanical stress by applying a single impulsive force, e.g. by falling weight
- G01N3/303—Investigating strength properties of solid materials by application of mechanical stress by applying a single impulsive force, e.g. by falling weight generated only by free-falling weight
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- 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
- G01N2203/00—Investigating strength properties of solid materials by application of mechanical stress
- G01N2203/0001—Type of application of the stress
- G01N2203/001—Impulsive
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N2203/00—Investigating strength properties of solid materials by application of mechanical stress
- G01N2203/003—Generation of the force
- G01N2203/0032—Generation of the force using mechanical means
- G01N2203/0039—Hammer or pendulum
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- 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 belongs to the technical field of static test of helicopters, and relates to a composite material drop hammer impact loading test device. The impact loading test device comprises a guide rail fixing top plate, a cylindrical guide rail, a magnetic fixing seat, an impact hammer, a guide rail fixing bottom plate, a guide rail supporting seat, a fixing disk and a test piece supporting seat. Wherein, be provided with in the middle of the guide rail supporting seat and strike the through-hole, encircle to strike the through-hole and be provided with guide rail PMKD, the cylinder guide rail of three even circumference range at least passes through guide rail PMKD and encircles the setting around strikeing the through-hole, the fixed disk is fixed to be cup jointed in cylinder guide rail top, and the jump bit setting is in the fixed disk below, and the magnetic force fixing base sets up in the fixed disk top, the testpieces supporting seat is located the guide rail supporting seat and issues to just. The invention can realize instant resistance-free falling, has less intermediate energy loss, reduces the discreteness of test data, improves the test precision, has simple structure and is easy to implement and operate.
Description
Technical Field
The invention belongs to the technical field of static tests of helicopters, and relates to a composite material drop hammer impact loading test device.
Background
With the deep application of composite materials in the fields of aviation, aerospace and the like, the research on the residual strength of the composite material structure as an energy absorption material and the damaged composite material gradually becomes the focus at home and abroad, so that the test of the impact load of the composite material laminated plate is more and more.
When the domestic composite material impact test is mainly carried out, an impact testing machine and a manual drop hammer impact device are mainly used for testing. And the manual impact test device mainly adopts the ASTM standard: d7136 requires a design, the test device is easy to cause energy loss and secondary impact during testing, the discrete coefficient of the test data is high, and the test data is analyzed to be caused by the following reasons: 1. the cylindrical guide rail and the cylindrical impact hammer generate friction with the wall of the guide rail when falling in the guide rail; 2. the height of the impact hammer is adjusted by adjusting the position of the bolt, and when the pull pin falls down, the impact hammer falls unstably and collides with the guide rail; 3. the impact hammer has smaller mass, and cannot bounce due to non-frontal impact after impacting with a test piece, thereby causing secondary damage. And the falling energy is adjusted by the height of the hole, so that the energy is discontinuous, and when the impact hammer is placed, the impact hammer needs to be lifted by a rope, which is very inconvenient. In addition, this test fixture does not have the secondary impact device of preventing, and during the experiment, adopt the tester to insert between impact head and the test piece with rigidity piece (wood, metal), prevent the secondary impact, operate inconvenient and cause the tester injured easily like this.
Disclosure of Invention
In view of the above-mentioned circumstances of the prior art, an object of the present invention is to provide an impact loading test apparatus.
The technical scheme of the invention is as follows: an impact loading test device comprises a guide rail fixing top plate (1), a cylindrical guide rail (2), a magnetic seat fixing seat (3), an impact hammer (4), a guide rail fixing bottom plate (5), a guide rail supporting seat (6), a fixing disk and a test piece supporting seat, wherein, the middle of the guide rail supporting seat 6 is provided with an impact through hole, a guide rail fixing bottom plate is arranged around the impact through hole, at least three cylindrical guide rails which are uniformly and circumferentially arranged are arranged around the impact through hole through the guide rail fixing bottom plate, the top of the cylindrical guide rail is provided with a guide rail fixing top plate, the fixed disk is fixedly sleeved above the cylindrical guide rail, the impact hammer is arranged below the fixed disk, the magnetic fixing seat is arranged above the fixed disk, and the magnetic force fixing seat adsorbs the impact hammer below the magnetic force fixing seat through the fixing disc, and the test piece supporting seat is positioned under the guide rail supporting seat and is opposite to the impact through hole.
And a switch which is opened and closed by magnetic force is arranged on the magnetic fixing seat.
The impact hammer is composed of an impact head and an impact seat, wherein the impact head is a round head, the root of the impact head is in threaded connection with the impact seat, the impact seat is of a disc-shaped structure, and the impact head is attached to the lower portion of the fixed disc through magnetic force.
The test piece supporting seat comprises a pillar main body, a baffle sliding groove (7), a baffle (8) and a baffle traction rod (9), wherein the pillar main body is of a frame structure, the top end face of the pillar main body is provided with an empty groove, the baffle sliding groove is arranged on the top end face of the pillar main body, the middle of the baffle sliding groove is provided with the empty groove, the sliding groove is internally provided with the sliding groove, the baffle is arranged in the baffle sliding groove and is positioned above the empty groove, one end of the baffle is connected with a spring, and the other end of the baffle is connected with the baffle.
And the baffle traction rod penetrates through a through hole at the end part of the baffle chute and then is connected with an external traction mechanism.
And scales for marking the height of the impact hammer are arranged on the cylindrical guide rail.
The cylindrical guide rail is three smooth cylinders.
The inner side of the cylindrical guide rail protrudes out of the inner wall of the guide rail fixing bottom plate (5).
The invention has the technical effects that: the impact loading device is used for the impact damage test of metal and composite materials, and has the following advantages compared with the conventional impact device:
(1) the impact device enables the impact hammer to fall freely, the energy loss in the middle is less, the discreteness of test data is reduced, the test precision is improved, the test is fast to change, the time is saved, and the working efficiency is improved.
(2) The device has low processing cost and convenient use.
(3) The appearance is pleasing to the eye, compact structure, and the device stability is high.
The impact loading device is applied to a composite material test of a certain type of machine, so that the test efficiency and the accuracy of a test result are greatly improved, and the application effect is good.
Drawings
FIG. 1 is a schematic view of an impact device;
FIG. 2(a) is a schematic structural view of a guide rail fixing top plate;
FIG. 2(b) the schematic view of the structure of the guide rail fixing base plate
FIG. 3 shows a magnetic fixing base
FIG. 4 is a schematic view of the impact hammer;
FIG. 5 is a front view of a test piece support base;
FIG. 6 is a top view of a test piece support seat;
FIG. 1 is a schematic view of an impact test,
the device comprises a guide rail fixing top plate 1, a cylindrical guide rail 2, a magnetic base fixing seat 3, an impact hammer 4, a guide rail fixing bottom plate 5, a guide rail supporting seat 6, a baffle sliding groove 7, a baffle 8 and a baffle traction rod 9.
Detailed Description
The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the 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.
Please refer to fig. 1, which is a schematic structural diagram of an impact loading test apparatus according to the present invention. In this embodiment, the impact loading test device includes guide rail fixed roof (1), cylinder guide rail (2), magnetic force fixing base (3), jump bit (4), guide rail PMKD (5), guide rail supporting seat (6), fixed disk, test piece supporting seat. The guide rail supporting seat 6 is of a frame structure with a pillar, an impact through hole is formed in the middle of the upper end table top, and a guide rail fixing bottom plate is arranged around the impact through hole. The guide rail fixing plate is of an annular structure and is fixed on the table top through screws, and a plurality of cylindrical guide rail mounting holes are formed in the guide rail fixing plate, as shown in figure 2.
The cylinder guide rail is three smooth cylinders, and scales for marking the height of the impact hammer are carved on the surface of the cylinder guide rail. The inner side of the cylindrical guide rail protrudes out of the inner wall of the guide rail fixing bottom plate (5) so as to avoid the impact hammer from touching the guide rail fixing plate when falling.
The top of the cylindrical guide rail is provided with a guide rail fixing top plate, the fixing plate is of a metal disc structure, and the fixing plate is fixedly sleeved above the cylindrical guide rail. The magnetic fixing seat is arranged above the fixed disk and is provided with a switch capable of closing magnetic force, and when the magnetic switch is turned on, the magnetic fixing seat is provided with magnetic force so as to generate magnetic adsorption force.
Referring to fig. 3, the impact hammer is composed of an impact head and an impact seat, the impact head is a ball head, and is point-contacted during impact to have an optimal impact effect, and the root of the impact hammer is in threaded connection with the impact seat. And the impact head is made of 30CrMnSiA and is subjected to heat treatment, so that the impact head is not easy to deform. The impact seat is of a disc-shaped structure and made of ferromagnetic metal, and can be attached to the lower portion of the fixed disc by the magnetic force of the magnetic fixed seat.
Referring to fig. 4, the test piece support seat is located under the guide rail support seat and faces the impact through hole. The test piece supporting seat comprises a pillar main body, a baffle sliding groove (7), a baffle (8) and a baffle traction rod (9), wherein the pillar main body is of a frame structure, the top end face of the pillar main body is provided with an empty groove, the baffle sliding groove is arranged on the top end face of the pillar main body, the middle of the baffle sliding groove is provided with the empty groove, the sliding groove is arranged inside the baffle sliding groove, the baffle is arranged in the baffle sliding groove and is positioned above the empty groove, one end of the baffle is connected with a spring, and the other end of the baffle is connected with the. The baffle plate traction rod penetrates through a through hole in the end part of the baffle plate sliding groove and then is connected with an external traction mechanism, and after the impact hammer impacts, the baffle plate traction rod is pulled, so that the baffle plate covers the empty groove, and the impact hammer is prevented from falling back to impact a test piece for the second time.
When the impact loading test device is used for testing, the device shown in the figure 1 is fixed on the ground, the quality and the position of the impact hammer are adjusted according to the impact energy requirement, the magnetic force seat is opened to fix the impact hammer by means of magnetic attraction, then the test piece supporting seat shown in the figure 2 is placed below the guide rail, the impact hammer is released to impact a test piece, the impact hammer is separated from the test piece after being bounced, the traction rod is pulled to block the impact hammer, and one-time impact test is completed.
The invention has the key points that the guide rails (2) are three smooth cylinders and are fixed on the guide rail supporting seat (6) through the rail fixing top plate (1) and the guide rail fixing bottom plate (5), the connection mode is not limited, and one of the guide rails (2) is provided with dimension scales for marking the height of the impact hammer (4); the outer contour of the impact hammer (4) is a part of a spherical surface (shown in figure 3), so that the impact hammer (4) is in approximate point contact with the guide rail (2), the friction force is reduced, and the mass of the impact hammer (4) can be adjusted by increasing a weight block; the impact hammer (4) is fixed in a magnetic attraction mode and can be released instantly; after the impact hammer (4) falls down, the traction rod (9) is pulled manually to drive the baffle (8) to prevent the impact hammer (4) from damaging a test piece for many times, the baffle (8) can automatically return to the original position by utilizing a spring mechanism, and a bearing can be installed at the contact part in order to ensure that the baffle (8) moves smoothly in the baffle sliding groove (7).
The above examples are merely illustrative of the present invention and are not intended to be part of the conventional art. The scope of the present invention is not limited thereto, and any changes or substitutions that can be easily made by those skilled in the art within the technical scope of the present invention will be covered by the scope of the present invention. The protection scope of the present invention shall be subject to the protection scope of the claims.
Claims (8)
1. An impact loading test device is characterized by comprising a guide rail fixing top plate (1), a cylindrical guide rail (2), a magnetic fixing seat (3), an impact hammer (4), a guide rail fixing bottom plate (5), a guide rail supporting seat (6), a fixing disk and a test piece supporting seat, wherein, the middle of the guide rail supporting seat 6 is provided with an impact through hole, a guide rail fixing bottom plate is arranged around the impact through hole, at least three cylindrical guide rails which are uniformly and circumferentially arranged are arranged around the impact through hole through the guide rail fixing bottom plate, the top of the cylindrical guide rail is provided with a guide rail fixing top plate, the fixed disk is fixedly sleeved above the cylindrical guide rail, the impact hammer is arranged below the fixed disk, the magnetic fixing seat is arranged above the fixed disk, and the magnetic force fixing seat adsorbs the impact hammer below the magnetic force fixing seat through the fixing disc, and the test piece supporting seat is positioned under the guide rail supporting seat and is opposite to the impact through hole.
2. The impact loading test device of claim 1, wherein the magnetic force fixing seat is provided with a switch which is opened and closed by magnetic force.
3. The impact loading test device of claim 2, wherein the impact hammer comprises an impact head and an impact seat, the impact head is a round head, the root of the impact head is in threaded connection with the impact seat, and the impact seat is in a disc-shaped structure and is attached below the fixed disc through magnetic force adsorption.
4. The impact loading test device according to claim 1, wherein the test piece supporting seat comprises a pillar body, a baffle sliding groove (7), a baffle (8) and a baffle traction rod (9), wherein the pillar body is of a frame structure, the top end surface of the pillar body is provided with a hollow groove, the baffle sliding groove is arranged on the top end surface of the pillar body, the middle of the pillar body is provided with the hollow groove, the baffle sliding groove is internally provided with the sliding groove, the baffle is arranged in the baffle sliding groove and positioned above the hollow groove, one end of the baffle is connected with the spring, and the other end of the baffle is connected with the baffle traction rod.
5. The impact loading test apparatus of claim 4, wherein the baffle drawbar is connected to the external drawbar after passing through the through hole at the end of the baffle chute.
6. The impact loading test apparatus of claim 4, wherein the cylindrical guide rail is provided with a scale for indicating the height of the impact hammer.
7. The impact loading test apparatus of claim 4, wherein said cylindrical guide is three smooth cylinders.
8. The impact loading test apparatus according to claim 1, wherein the inner side of said cylindrical guide rail protrudes from the inner wall of the guide rail fixing base plate (5).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911074716.5A CN111077028A (en) | 2019-11-05 | 2019-11-05 | Impact loading test device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911074716.5A CN111077028A (en) | 2019-11-05 | 2019-11-05 | Impact loading test device |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN111077028A true CN111077028A (en) | 2020-04-28 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201911074716.5A Pending CN111077028A (en) | 2019-11-05 | 2019-11-05 | Impact loading test device |
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| CN (1) | CN111077028A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113720566A (en) * | 2021-08-23 | 2021-11-30 | 中国飞机强度研究所 | Secondary impact prevention device and method and drop hammer impact test device with same |
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Application publication date: 20200428 |
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