CN208043623U - A kind of static and dynamic friction coefficient testing machine - Google Patents
A kind of static and dynamic friction coefficient testing machine Download PDFInfo
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- CN208043623U CN208043623U CN201820440870.4U CN201820440870U CN208043623U CN 208043623 U CN208043623 U CN 208043623U CN 201820440870 U CN201820440870 U CN 201820440870U CN 208043623 U CN208043623 U CN 208043623U
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Abstract
The utility model discloses a kind of static and dynamic friction coefficient testing machines, it is related to the field of testing a machine, including chassis, transmission mechanism, mechanism for testing, hitch structure, transmission mechanism is located above chassis, transmission mechanism is equipped with motor and horizontal screw bolt, horizontal screw bolt is equipped with connecting seat, it is installed with nut seat below mechanism for testing, nut seat connects connecting seat, friction bottom plate is additionally provided on mechanism for testing, the bottom plate that rubs is equipped with briquetting, briquetting lower part can post sample, sample and friction contacts baseplate, hitch structure connects briquetting, strength sensor in hitch structure measures frictional force size.By the way that the friction bottom plate needed and experiment is arranged, linear uniform motion then occurs using motor driving mechanism for testing, the frictional force size during measuring experiment difference using strength sensor, to calculate static and dynamic friction coefficient.Work efficiency is high, easy to use, reasonable for structure.
Description
Technical field
The utility model is related to test machines fields, more particularly to a kind of static and dynamic friction coefficient testing machine.
Background technology
Friction coefficient is commonly divided into confficient of static friction and the coefficient of sliding friction, the material with the contact surface of contact surface,
Degree of roughness is related, in real process, often considers the friction coefficient between two objects, such as the saddle in sport gymnastics
Horse, curling stone match etc., or industry, field of traffic etc..
Existing measurement method mostly uses inclined plane method, by the way that object placement in the plane, is changed the inclined degree of plane,
Until object can move just, friction coefficient is calculated whereby.But this measuring and calculating mode, it can only be used for
To confficient of static friction, in practical situations, the coefficient of kinetic friction is less than confficient of static friction, and inclined plane method can not measure the coefficient of kinetic friction.
It is another using static and dynamic friction coefficient is calculated by the way of traction object block by hand in the plane uniform motion, this mode of operation passes through
The operating experience of operator is often leaned on, precision is low, and time-consuming.
Utility model content
For prior art disadvantage, the utility model discloses a kind of static and dynamic friction coefficient testing machines, are driven using motor
Mechanism for testing acquires friction force information using strength sensor, calculates static and dynamic friction coefficient, easy to use, reasonable for structure, has
Imitate lifting test efficiency and precision.Its particular technique feature is as follows：
A kind of static and dynamic friction coefficient testing machine, including chassis, transmission mechanism, mechanism for testing, hitch structure；
The transmission mechanism is fixedly mounted on above chassis, and transmission mechanism includes workbench, and motor is equipped with below workbench,
Horizontal screw bolt is equipped with above workbench, horizontal screw bolt both ends are connected with horizontal screw bolt mounting base, and horizontal screw bolt mounting base is fixed on
Above workbench, bearing block is equipped at left and right sides of horizontal screw bolt, the bearing block is fixed on the table, the transmission of the motor
One end of axis and horizontal screw bolt is connected with belt, and connecting seat is equipped in the middle part of horizontal screw bolt, and connecting seat is threadedly coupled with horizontal screw bolt；
The mechanism for testing includes testboard, and guide rod is equipped with below the testboard, and guide rod is arranged in parallel with horizontal screw bolt,
Guide rod both ends be equipped with it is leader fixed, the bearing block in matching guide bars transmission mechanism, guide rod is fixedly connected with leader fixed, is led
Bar fixed seat is fixedly mounted below testboard, and lower section is equipped with nut seat in the middle part of testboard, and nut seat connects on transmission mechanism
Connecting seat, testboard top are installed with test board, and top is equipped with fixed plate in the middle part of test board, and fixed plate middle part is equipped with friction bottom
Plate, friction bottom plate top are equipped with briquetting, and sample is posted in briquetting bottom；
The hitch structure includes column, and column is fixed on the test board of mechanism for testing, and column side attachment force amount passes
One end of sensor, the other end connecting steel wire ropes of strength sensor, the steel wire rope other end connect briquetting；
The chassis side is equipped with display screen, and display screen connects the signal output end of strength sensor, and tray side is equipped with
Power switch, power switch connect motor.
Further, level meter is additionally provided on the test board of mechanism for testing, the chassis bottom is equipped with levelling foot.
Further, column is hollow, and vertical screw is equipped in column, and column is threadedly coupled with vertical screw, vertical screw
Top is equipped with handwheel, and column side offers shifting chute, and connector is equipped in shifting chute, and connector one end passes through shifting chute and hangs down
Straight screw flight connection, the connector other end connect strength sensor.
Further, chassis side is equipped with control panel, and the display screen is arranged on the control panel, the control panel
On be additionally provided with emergency stop switch.
Further, workbench is equipped with limit switch, and limit switch is mounted on limit switch frame, the limit switch
Frame is fixed on the table, and limit switch is adjacent with bearing block, and mechanism for testing is equipped with and is matched with the limit switch on workbench
Limit switch touch piece, the limit switch touches piece and is arranged in leader fixed side.
Further, strength sensor is externally provided with arc surfaced baffle, and the cabochon baffle side is seen is in one section of central angle
270 degree to 350 degree of circular arc.
The beneficial effects of the utility model are：By the way that the friction bottom plate needed and experiment is arranged, then driven using motor
Linear uniform motion occurs for mechanism for testing, the frictional force size during measuring experiment difference using strength sensor, to
Calculate static and dynamic friction coefficient.Work efficiency is high, easy to use, reasonable for structure.
Description of the drawings
Fig. 1 is the structural schematic diagram of the utility model embodiment；
Fig. 2 is the structural schematic diagram of the utility model embodiment chassis；
Fig. 3 is the side structure schematic diagram of the utility model embodiment transmission mechanism；
Fig. 4 is the vertical view of the utility model embodiment transmission mechanism
Fig. 5 is the structural schematic diagram of the utility model embodiment mechanism for testing；
Fig. 6 is the upward view of the utility model embodiment mechanism for testing；
Fig. 7 is the structural schematic diagram of the utility model embodiment hitch structure；
Fig. 8 is the sectional view of the utility model embodiment hitch structure.
It is identified in figure：
Transmission mechanism 10, workbench 11, motor 12, horizontal screw bolt 13, horizontal screw bolt mounting base 14, bearing block 15, belt
16, connecting seat 17, limit switch 18, limit switch frame 19, mechanism for testing 20, testboard 21, guide rod 22, leader fixed 23,
Nut seat 24, test board 25, fixed plate 26, rub bottom plate 27, briquetting 28, sample 29, and limit switch touches piece 30, level meter
31, hitch structure 40, column 41, strength sensor 42, steel wire rope 43, vertical screw 44, handwheel 45, shifting chute 46, connector
47, arc surfaced baffle 48, chassis 50, display screen 51, levelling foot 52, control panel 53, emergency stop switch 54, power switch 55.
Specific implementation mode
For that can further appreciate that the feature, technological means and the specific purposes reached, function of the utility model, below
The utility model is described in further detail with specific implementation mode in conjunction with attached drawing.
Attached drawing is please referred to, the present embodiment is a kind of static and dynamic friction coefficient testing machine, for calculating sample 29 and friction bottom plate
Kinematics and static friction coefficient magnitude between 27 comprising chassis 50, transmission mechanism 10, mechanism for testing 20, hitch structure 40.
Transmission mechanism 10 is fixedly mounted on 50 top of chassis, and transmission mechanism 10 includes workbench 11, and 11 lower section of workbench is set
There are motor 12,11 top of workbench to be equipped with horizontal screw bolt 13,13 both ends of horizontal screw bolt are connected with horizontal screw bolt mounting base 14, horizontal
Screw rod mounting base 14 is fixed on 11 top of workbench, and 13 left and right sides of horizontal screw bolt is equipped with bearing block 15, and bearing block 15 is fixed on
On workbench 11, the transmission shaft of motor 12 is connect with one end belt 16 of horizontal screw bolt 13, and 13 middle part of horizontal screw bolt, which is equipped with, to be connected
Joint chair 17, connecting seat 17 are threadedly coupled with horizontal screw bolt 13, and the operation of motor 12 drives belt 16, to drive horizontal screw bolt 13 to transport
Dynamic, then connecting seat 17 moves.
Mechanism for testing 20 includes testboard 21, and 21 lower section of testboard is equipped with guide rod 22, and guide rod 22 is parallel with horizontal screw bolt 13
Setting, 22 both ends of guide rod are equipped with leader fixed 23, and guide rod 22 matches the bearing block 15 in transmission mechanism 10, guide rod 22 and guide rod
Fixed seat 23 is fixedly connected, and leader fixed 23 are fixedly mounted on 21 lower section of testboard, and 21 middle part lower section of testboard is equipped with nut
Seat 24, nut seat 24 connect the connecting seat 17 on transmission mechanism 10, and the top of testboard 21 is installed with test board 25, in test board 25
Fixed plate 26 is equipped with above portion, 26 middle part of fixed plate is equipped with friction bottom plate 27, and 27 top of friction bottom plate is equipped with briquetting 28, briquetting 28
Post sample 29 in bottom.The guide rod 22 of the present embodiment is two, and two guide rods 22 are located at 24 left and right sides of nut seat, and guide rod 22 stretches into
On the bearing block 15 of transmission mechanism 10, it can be used for limiting and keep stabilization of the mechanism for testing 20 in moving process.Connecting seat 17
Upper fixing nut seat 24, the movement of connecting seat 17 can drive nut seat 24 to drive testboard 21 to move, and fixed plate 26 is fixed on
On test board 25, the present embodiment offers square through hole at 26 middle part of fixed plate, and the setting friction bottom plate 27 in through-hole, rub bottom
Plate 27 can be replaced.
Hitch structure 40 includes column 41, and column 41 is fixed on the test board 25 of mechanism for testing 20, and 41 side of column connects
One end of relay quantity sensor 42, the other end connecting steel wire ropes 43 of strength sensor 42,43 other end of steel wire rope connect briquetting
28。
50 side of chassis is equipped with display screen 51, and display screen 51 connects the signal output end of strength sensor 42, for showing
Rub force information, and 50 side of chassis is equipped with power switch 55, and power switch 55 connects motor 12, strength sensor 42 and display
Screen 51 can connect power switch 55 or connection battery.
In the specific use process, as required, on smooth ground, testing machine is placed, installs friction bottom plate 27,
Suitable briquetting 28 is selected, sample 29 is posted below briquetting 28, briquetting 28 is connect with steel wire rope 43, and keep steel wire rope 43
In exceptionally straight state, before use, the nut seat 24 of mechanism for testing 20 is mounted on the connecting seat 17 of transmission mechanism 10, by guide rod 22
It is sleeved in bearing block 15, and adjusts the position of mechanism for testing 20, in use, turning on the power switch 55, start motor 12, motor
12 operations, drive belt 16, and to drive horizontal screw bolt 13 to rotate, the connecting seat 17 on horizontal screw bolt 13 generates horizontal displacement,
It drives nut seat 24 to move, exactly testboard 21 is driven to move simultaneously, at this point, friction bottom plate 27 moves, briquetting 28 is tied in traction
Under the influence of structure 40 and relative displacement occurs for friction bottom plate 27, and strength sensor 42 measures the frictional force that relative movement occurs
Size shows in display screen 51, can also external computer, using the variation of computer record frictional force size, or even draw and rub
Power change curve is wiped, and calculates the coefficient of kinetic friction and confficient of static friction.
Its principle is, 12 power invariability of motor during this, the quality of mechanism for testing 20 be ten times of 28 mass of briquetting extremely
100 times, to ignore 28 mass of briquetting in the calculation, link block and mechanism for testing 20, which can be regarded as, is doing uniform rectilinear's fortune
It is dynamic.When briquetting 28 and sample 29, briquetting 28 is most by the size of frictional force when relative motion occurring just with friction bottom plate 27
The size of big stiction, sample 29 should be frivolous so that 28 mass of briquetting is ten times to 100 times of sample 29, to count
29 mass of sample, subsequent briquetting 28 and sample 29 can be ignored in calculation, it is opposite with friction bottom plate 27 to do linear uniform motion, at this time
Strength sensor 42 records the size of force of sliding friction, 28 gravity of above-mentioned frictional force divided by briquetting, as confficient of static friction and dynamic
The numerical value of friction coefficient.
The present embodiment is to improve applicability, and level meter 31 is arranged on test board 25, and levelling foot is arranged in 50 bottom of chassis
52,52 quantity of levelling foot is four and is respectively on 50 4 angles of chassis, adjusts levelling foot 52 so that the display of level meter 31 is surveyed
Test stand 21 is located at horizontality.
To coordinate different size of briquetting 28, the column 41 of hitch structure 40 is hollow, and vertical screw 44 is set in column 41, stands
Column 41 is threadedly coupled with vertical screw 44, and 44 top of vertical screw is equipped with handwheel 45, and 41 side of column offers shifting chute 46, moves
It is equipped with connector 47 in dynamic slot 46,47 one end of connector is threadedly coupled across shifting chute 46 with vertical screw 44, and connector 47 is another
One end connects strength sensor 42.Adjusting handle 45 can change the height of connector 47, so that steel wire rope 43 is in
Horizontality.
The present embodiment is equipped with control panel 53 in 50 side of chassis, and display screen 51 is arranged on control panel 53, control plane
It is additionally provided with emergency stop switch 54 on plate 53, promotes the safety used.
To avoid mechanism for testing 20 from tampering, limit switch 18 is equipped on workbench 11, limit switch 18 is mounted on limit
On switch frame 19, limit switch frame 19 is fixed on workbench 11, and limit switch 18 is adjacent with bearing block 15, on mechanism for testing 20
Equipped with piece 30 is touched with the 18 matched limit switch of limit switch on workbench 11, limit switch touches piece 30 and is arranged in guide rod
23 side of fixed seat, limit switch touches piece 30 rotatably, when needing to limit mechanism for testing 20, mobile test mechanism
20, rotary spacing switch actuating piece 30 so that limit switch touches piece 30 and is stuck on limit switch 18, to avoid mechanism for testing
20 tamper.It can also use other limit methods such as magnet.
In addition, to ensure that precision, strength sensor 42 are externally provided with arc surfaced baffle 48, cabochon baffle side is seen in one section of circle
The circular arc that heart angle is 350 degree, can avoid strength sensor 42 is caused by ectocine using abnormal.
A kind of embodiment of the utility model above described embodiment only expresses, the description thereof is more specific and detailed,
But it should not be understood as limiting the scope of the patent of the utility model.It should be pointed out that for the common of this field
For technical staff, without departing from the concept of the premise utility, various modifications and improvements can be made, these all belong to
In the scope of protection of the utility model.Therefore, the protection domain of the utility model patent should be determined by the appended claims.
Claims (6)
1. a kind of static and dynamic friction coefficient testing machine, which is characterized in that including chassis (50), transmission mechanism (10), mechanism for testing
(20), hitch structure (40)；
The transmission mechanism (10) is fixedly mounted on above chassis (50), and transmission mechanism (10) includes workbench (11), workbench
(11) lower section is equipped with motor (12), is equipped with horizontal screw bolt (13) above workbench (11), horizontal screw bolt (13) both ends are connected with water
Flat screw rod mounting base (14), horizontal screw bolt mounting base (14) are fixed on above workbench (11), at left and right sides of horizontal screw bolt (13)
Equipped with bearing block (15), the bearing block (15) is fixed on workbench (11), transmission shaft and the horizontal spiral shell of the motor (12)
One end of bar (13) is connected with belt (16), and connecting seat (17), connecting seat (17) and horizontal spiral shell are equipped in the middle part of horizontal screw bolt (13)
Bar (13) is threadedly coupled；
The mechanism for testing (20) includes testboard (21), is equipped with guide rod (22) below the testboard (21), guide rod (22) with
Horizontal screw bolt (13) is arranged in parallel, and guide rod (22) both ends are equipped with leader fixed (23), guide rod (22) and leader fixed (23)
It is fixedly connected, leader fixed (23) are fixedly mounted below testboard (21), and lower section is equipped with nut seat in the middle part of testboard (21)
(24), the connecting seat (17) on nut seat (24) connection transmission mechanism (10), testboard (21) top are installed with test board (25),
Top is equipped with fixed plate (26) in the middle part of test board (25), and friction bottom plate (27), friction bottom plate (27) are equipped in the middle part of fixed plate (26)
Top is equipped with briquetting (28), and sample (29) is posted in briquetting (28) bottom；
The hitch structure (40) includes column (41), and column (41) is fixed on the test board (25) of mechanism for testing (20), is stood
Column (41) side connects one end of strength sensor (42), the other end connecting steel wire ropes (43) of strength sensor (42), steel wire
(43) other end of restricting connects briquetting (28)；
Chassis (50) side is equipped with display screen (51), and display screen (51) connects the signal output end of strength sensor (42),
Chassis (50) side is equipped with power switch (55), and power switch (55) connects motor (12).
2. according to a kind of static and dynamic friction coefficient testing machine described in claim 1, which is characterized in that the mechanism for testing (20)
Test board (25) on be additionally provided with level meter (31), chassis (50) bottom is equipped with levelling foot (52).
3. a kind of static and dynamic friction coefficient testing machine according to claims 1 or 2, which is characterized in that the column (41)
It is hollow, vertical screw (44) is equipped in column (41), column (41) is threadedly coupled with vertical screw (44), vertical screw (44) top
Portion is equipped with handwheel (45), and column (41) side offers shifting chute (46), connector (47), connector are equipped in shifting chute (46)
(47) one end is threadedly coupled across shifting chute (46) with vertical screw (44), and connector (47) other end connects strength sensor
(42)。
4. a kind of static and dynamic friction coefficient testing machine according to claims 1 or 2, which is characterized in that the chassis (50)
Side is equipped with control panel (53), and the display screen (51) is arranged on control panel (53), on the control panel (53) also
Equipped with emergency stop switch (54).
5. a kind of static and dynamic friction coefficient testing machine according to claims 1 or 2, which is characterized in that the workbench
(11) it is equipped with limit switch (18), limit switch (18) is mounted on limit switch frame (19), the limit switch frame (19)
It is fixed on workbench (11), limit switch (18) is adjacent with bearing block (15), and mechanism for testing (20) is equipped with and workbench
(11) the matched limit switch of limit switch (18) on touches piece (30), and the limit switch touches piece (30) and is arranged in guide rod
Fixed seat (23) side.
6. according to a kind of static and dynamic friction coefficient testing machine described in claim 3, which is characterized in that the strength sensor
(42) it is externally provided with arc surfaced baffle (48), the cabochon baffle side sees that in one section of central angle be 270 degree to 350
The circular arc of degree.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201820440870.4U CN208043623U (en) | 2018-03-28 | 2018-03-28 | A kind of static and dynamic friction coefficient testing machine |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201820440870.4U CN208043623U (en) | 2018-03-28 | 2018-03-28 | A kind of static and dynamic friction coefficient testing machine |
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| Publication Number | Publication Date |
|---|---|
| CN208043623U true CN208043623U (en) | 2018-11-02 |
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| CN201820440870.4U Active CN208043623U (en) | 2018-03-28 | 2018-03-28 | A kind of static and dynamic friction coefficient testing machine |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114324145A (en) * | 2021-12-28 | 2022-04-12 | 广州特种机电设备检测研究院 | Escalator step pedal friction measuring device |
| CN116296971A (en) * | 2023-05-24 | 2023-06-23 | 江苏裕科新材料有限公司 | Device and method for testing wear resistance of wood-plastic floor |
-
2018
- 2018-03-28 CN CN201820440870.4U patent/CN208043623U/en active Active
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114324145A (en) * | 2021-12-28 | 2022-04-12 | 广州特种机电设备检测研究院 | Escalator step pedal friction measuring device |
| CN114324145B (en) * | 2021-12-28 | 2024-02-06 | 广州特种机电设备检测研究院 | Friction measuring device for escalator step pedal |
| CN116296971A (en) * | 2023-05-24 | 2023-06-23 | 江苏裕科新材料有限公司 | Device and method for testing wear resistance of wood-plastic floor |
| CN116296971B (en) * | 2023-05-24 | 2023-08-22 | 江苏裕科新材料有限公司 | Device and method for testing wear resistance of wood-plastic floor |
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