CN211505158U

CN211505158U - Stepless pressure regulating friction coefficient measuring instrument

Info

Publication number: CN211505158U
Application number: CN201922465782.7U
Authority: CN
Inventors: 陈明达; 王建梅; 宁可; 侯定邦
Original assignee: Taiyuan University of Science and Technology
Current assignee: Taiyuan University of Science and Technology
Priority date: 2019-12-31
Filing date: 2019-12-31
Publication date: 2020-09-15
Anticipated expiration: 2029-12-31

Abstract

The utility model relates to a stepless pressure regulating friction coefficient measuring apparatu, the purpose is solved current orthoscopic friction coefficient measuring apparatu and can only be when normal pressure is the definite value measure friction coefficient, can't realize stepless pressure regulating, can not the accurate control normal pressure size, can't provide the technical problem of enough big normal pressure. The utility model discloses a frame, establish the guide rail in the frame, the power unit that sets up on frame and guide rail, test platform down, go up test platform, pneumatic loading system, normal pressure's infinitely variable control when friction coefficient is measured in realization such as frictional force collection mechanism, and the pressure upper limit that can provide is big, two upper and lower friction surfaces can be changed, set up clamping mechanism and fixed establishment down on the test platform, the adjustability makes this measuring apparatu require lowly to the size and the shape of test piece, the measurement flow has been simplified. The device has the advantages of adjustable normal pressure, capability of providing large-load normal pressure, capability of testing various material combinations, low requirement on test piece processing, convenience and firmness in test piece installation and the like.

Description

Stepless pressure regulating friction coefficient measuring instrument

Technical Field

The utility model belongs to coefficient of friction measures the field, concretely relates to stepless pressure regulating coefficient of friction measuring apparatu.

Background

The friction coefficient is a complex physical quantity, and has a certain relation with material properties, surface roughness, motion speed, normal pressure and the like. But current orthoscopic coefficient of friction measuring apparatu all can only measure coefficient of friction when normal pressure is the definite value generally, has some modified utility model also to adopt the mode that increases the weight to change normal pressure, nevertheless can not realize stepless pressure regulating, can not accurate control normal pressure size, also can not provide enough big normal pressure. The prior art does not meet the requirements in measuring the coefficient of friction of some heavy machinery metals.

In the prior art field of linear friction coefficient measuring instruments, for example, chinese utility model patent publication No. CN106092876B, a friction coefficient tester is disclosed, which provides a convenient friction coefficient measuring method and apparatus, but the normal pressure of the measured surface cannot be changed, and the normal pressure value is small. In the heavy mechanical engineering practice, the normal pressure of the measured surface is often very large, and may have a non-negligible effect on the measurement of the true value of the friction coefficient. Therefore, the friction coefficient measuring instrument is not suitable for the field of heavy machinery.

SUMMERY OF THE UTILITY MODEL

The utility model aims at solving the technical problem that the current orthoscopic coefficient of friction measuring apparatu can only measure coefficient of friction when normal pressure is the definite value, can't realize stepless pressure regulating, can not the accurate control normal pressure size, also can't provide enough big normal pressure, provide a stepless pressure regulating coefficient of friction measuring apparatu.

In order to solve the technical problem, the utility model discloses a technical scheme is:

a stepless pressure-regulating friction coefficient measuring instrument comprises a rack, guide rails arranged on two side edges of the rack, a power mechanism, a lower test platform, an upper test platform, a pneumatic pressurizing mechanism, a friction force acquisition mechanism, a distance sensor, a metal induction plate and a computer provided with a control system and a data processing system; the friction force acquisition mechanism is arranged on the other side of the bottom of the rack, and the distance sensor is arranged on the inner side wall of the rack mounting groove and is positioned below the lower test platform; the metal induction plate is arranged on the lower surface of the lower test platform;

the power mechanism is connected with the control system, the distance sensor is connected with the control system, the pneumatic pressurizing mechanism is connected with the control system, and the friction force acquisition mechanism is connected with the data processing system.

Furthermore, the power mechanism comprises a servo motor, a motor supporting seat, a diaphragm coupling, a ball screw, a nut seat, a ball screw supporting seat, a baffle and a supporting seat end cover; the servo motor is arranged on a motor supporting seat, the servo motor is connected with a control system, the motor supporting seat is arranged on one side of the bottom of a rack mounting groove, one end of the ball screw is connected with one end of the servo motor through a diaphragm coupling, the other end of the ball screw is provided with a ball screw supporting seat, the outer side of the ball screw supporting seat is provided with a baffle, and a supporting seat end cover is arranged on the baffle; and a nut seat is arranged in the middle of the ball screw and connected with the lower surface of the lower test platform.

Furthermore, the lower test platform comprises a lower objective table, sliding blocks are arranged on two sides of the bottom surface of the lower objective table, and the sliding blocks are arranged on the guide rails; a rectangular groove is formed in the middle of the lower objective table, a clamping mechanism is arranged on one side of the rectangular groove, and a fixing mechanism is arranged on the other side of the rectangular groove; and a lower test piece is placed in the rectangular groove and is fixed through a clamping mechanism and a fixing mechanism.

Further, go up test platform and include the objective table, be equipped with threaded connection head on going up an end face of objective table, the centre of going up the objective table is equipped with the objective groove, place the test piece in the objective groove, go up the other three terminal surface installation holding screw of objective table.

Further, the pneumatic pressurizing mechanism comprises a cylinder connecting seat, pillars are arranged on two sides of the cylinder connecting seat and fixed on bottom plates on two sides of the rack through the pillars, a cylinder is mounted on the cylinder connecting seat, an auxiliary motion connecting plate is mounted at the lower end of a piston rod of the cylinder, an auxiliary motion rod is perpendicularly mounted at one end of the auxiliary motion connecting plate, one end of the auxiliary motion rod perpendicularly penetrates through a hole formed in the cylinder connecting seat, the cylinder is connected with an air compressor, and the air compressor is connected with a control system.

Furthermore, the friction force acquisition mechanism comprises a base, a cylindrical shell is installed on the base, bearings are installed on the upper end and the lower end of the cylindrical shell, a screw rod is installed in each bearing, a sliding ring is installed on each screw rod, one end of each sliding ring is connected with a connecting block, each connecting block is connected with a tension sensor, one end of each tension sensor is connected with a dowel bar, each dowel bar is connected with an upper test platform, and each tension sensor is connected with a data processing system.

Further, the perpendicular distance between the metal induction plate and the induction head of the distance sensor is not more than mm.

Furthermore, the clamping mechanism comprises a threaded seat, the threaded seat is fixed on one side edge of the lower objective table, a screw rod is arranged in the threaded seat, and one end of the screw rod is provided with a clamp; the fixing mechanism comprises two fixing blocks, the two fixing blocks are fixed on the lower objective table and located on two sides of the rectangular groove, a plurality of threaded holes are formed in the fixing blocks, and fastening screws are installed in the threaded holes.

The utility model has the advantages that:

the utility model discloses a frame, establish the guide rail in the frame, the power unit that sets gradually on frame and guide rail, test platform down, go up test platform, pneumatic loading system, normal pressure's infinitely variable control when friction coefficient is measured in realization such as frictional force collection mechanism, and the pressure upper limit that can provide is big, two upper and lower friction surfaces can be changed, set up clamping mechanism and fixed establishment on the test platform down, the adjustability makes this measuring apparatu require lowly to the size and the shape of test piece, the measurement flow has been simplified. Therefore, the device has the advantages of adjustable normal pressure, capability of providing large-load normal pressure, capability of performing combination test of various materials, low requirement on test piece processing, convenience and firmness in test piece installation and the like.

Drawings

Fig. 1 is a schematic view of the overall structure of the present invention;

fig. 2 is a schematic structural view of the power mechanism of the present invention;

FIG. 3 is a schematic structural view of the lower test platform of the present invention;

fig. 4 is an exploded view of the upper test platform of the present invention;

fig. 5 is a schematic structural view of the pneumatic pressurizing mechanism of the present invention;

fig. 6 is a sectional view of the friction force collecting mechanism of the present invention;

fig. 7 is a schematic view of the installation positions of the distance sensor and the metal induction plate according to the present invention;

in the figure: a frame-1; the device comprises a power mechanism-2, a servo motor-21, a motor supporting seat-22, a diaphragm coupling-23, a ball screw-24, a nut seat-25, a ball screw supporting seat-26, a baffle-27 and a supporting seat end cover-28; the device comprises a lower test platform-3, a lower object-loading platform-31, a clamping mechanism-32, a screw-321, a threaded seat-322, a clamp-323, a rectangular groove-33, a lower test piece-34, a sliding block-35, a fixing mechanism-36, a fastening screw-361, a threaded hole-362 and a fixing block-363; an upper test platform-4, an objective table-41, a threaded connector-42, a set screw-43, an upper test piece-44 and an objective groove-45; the device comprises a pneumatic pressurizing mechanism-5, a strut-51, an air cylinder-52, an air cylinder piston rod-53, an auxiliary motion rod-54, an air cylinder connecting seat-55 and an auxiliary motion connecting plate-56; the device comprises a friction force acquisition mechanism-6, a tension sensor-61, a dowel bar-62, a connecting block-63, a cylindrical shell-64, a sliding ring-65, a screw-66, a bearing-67 and a base-68; a distance sensor-7; a guide rail-8; a metal induction plate-9.

Detailed Description

The invention will be further described with reference to the following examples and the accompanying drawings.

As shown in fig. 1, the stepless pressure-regulating friction coefficient measuring instrument according to the present embodiment includes a frame 1, guide rails 8 disposed on two side edges of the frame 1, a power mechanism 2, a lower test platform 3, an upper test platform 4, a pneumatic pressurizing mechanism 5, a friction force collecting mechanism 6, a distance sensor 7, a metal induction plate 9, and a computer equipped with a control system and a data processing system; the power mechanism 2 is arranged at the bottom of the mounting groove of the frame 1, the power mechanism 2 is used for providing power for the lower test platform 3 to do linear reciprocating motion, the lower test platform 3 is arranged on the guide rail 8 and is positioned above the power mechanism 2, the lower test platform 3 is used for loading a lower test piece 34, the upper test platform 4 is arranged above the lower test platform 3, the upper test platform 4 is used for placing an upper test piece 44, the pneumatic pressurizing mechanism 5 is arranged above the lower test platform 3 and the upper test platform 4 and is fixed on bottom plates at two sides of the frame 1 through a support 51, the pneumatic pressurizing mechanism 5 is used for providing stepless adjustable normal pressure for a surface to be tested, the friction force collecting mechanism 6 is arranged at the other side of the bottom of the frame 1 and is used for sensing and recording the friction force value, the distance sensor 7 is arranged on the inner side wall of the mounting groove of the frame 1 and is positioned below the lower test platform, in order to ensure that the lower test platform 3 does not interfere with other parts when moving forwards and backwards, the number of the distance sensors 7 is set to be 2;

as shown in fig. 7, the metal induction plate 9 is disposed on the lower surface of the lower testing platform 3; the vertical distance between the metal induction plate 9 and the induction head of the distance sensor 7 is not more than 10 mm. The distance sensor 7 and the metal induction plate 9 provide limiting protection for the motion stroke of the lower test platform 3, and the lower test platform 3 is prevented from interfering with other parts. When the test platform 3 works, when the test platform starts to move to the limit position, the metal induction plate 9 is close to the distance sensor 7, the distance sensor 7 generates an electric signal and transmits the electric signal to the control system, and the control system sends an instruction to enable the servo motor 21 to be powered off and stop working, so that the test platform 3 is protected from interfering with other components.

The power mechanism 2 is connected with a control system, the distance sensor 7 is connected with the control system, the pneumatic pressurizing mechanism 5 is connected with the control system, and the pneumatic pressurizing mechanism 5 and the servo motor 21 can be controlled by the control system respectively. The friction force acquisition mechanism 6 is connected with a data processing system.

As shown in fig. 2, the power mechanism 2 includes a servo motor 21, a motor support 22, a diaphragm coupling 23, a ball screw 24, a nut seat 25, a ball screw support seat 26, a baffle 27, and a support seat end cover 28; the servo motor 21 is arranged on the motor support seat 22, the servo motor 21 is connected with the control system, and the control system adjusts the starting, stopping and rotating speed of the servo motor 21 so as to control the stroke and speed of the linear motion of the lower test platform 3; the motor supporting seat 22 is installed on one side of the bottom of the installation groove of the rack 1, one end of the ball screw 24 is connected with one end of the servo motor 21 through a diaphragm coupling 23, the other end of the ball screw 24 is provided with a ball screw supporting seat 26, a baffle 27 is arranged on the outer side of the ball screw supporting seat 26, and a supporting seat end cover 28 is arranged on the baffle 27; the middle of the ball screw 24 is provided with a nut seat 25, the nut seat 25 is connected with the lower surface of the lower test platform 3, so that the ball screw 24 can be driven to rotate by the servo motor 21, and then the lower objective table 31 is driven to do linear motion by the nut seat 25.

As shown in fig. 3, the lower testing platform 3 includes a lower stage 31, two sides of the bottom surface of the lower stage 31 are provided with sliding blocks 35, and the sliding blocks 35 are installed on the guide rail 8; a rectangular groove 33 is formed in the middle of the lower object stage 31, a clamping mechanism 32 is arranged on one side of the rectangular groove 33, and a fixing mechanism 36 is arranged on the other side of the rectangular groove 33; the lower specimen 34 is placed in the rectangular groove 33, and the lower specimen 34 is fixed by the clamping mechanism 32 and the fixing mechanism 36. The clamping mechanism 32 comprises a threaded seat 322, the threaded seat 322 is fixed on one side of the lower objective table 31, a screw 321 is arranged in the threaded seat 322, one end of the screw 321 is provided with a clamp 323, the clamp 323 can be adjusted to move back and forth by rotating the screw 321 to clamp the lower test piece 34, and the lower test pieces 34 with different lengths can be clamped; the fixing mechanism 36 includes two fixing blocks 363, the two fixing blocks 363 are fixed on the lower stage 31 and located at two sides of the rectangular groove 33, the fixing blocks 363 are provided with a plurality of threaded holes 362, and fastening screws 361 are installed in the threaded holes 362, so that the lower test pieces 34 with different widths can be fixed.

In order to increase the smoothness of the linear motion of the lower test platform 3, the number of the sliding blocks 35 is set to 4.

In order to fix the lower test pieces 34 of different sizes, the number of the screw holes 362 on the fixing block 363 is set to 4.

As shown in fig. 4, the upper test platform 4 includes an upper stage 41, a threaded connector 42 is disposed on one end surface of the upper stage 41, a carrying groove 45 is disposed in the middle of the upper stage 41, an upper test piece 44 is disposed in the carrying groove 45, and set screws 43 are mounted on the other three end surfaces of the upper stage 41, so that the set screws 43 can fix the upper test pieces 44 with different sizes.

As shown in fig. 5, the pneumatic pressurizing mechanism 5 includes a cylinder connecting base 55, two sides of the cylinder connecting base 55 are provided with support columns 51 and are fixed on bottom plates at two sides of the frame 1 through the support columns 51, a cylinder 52 is installed on the cylinder connecting base 55, an auxiliary motion connecting plate 56 is installed at a lower end of a cylinder piston rod 53, an auxiliary motion rod 54 is vertically installed at one end of the auxiliary motion connecting plate 56, one end of the auxiliary motion rod 54 vertically penetrates through a hole formed in the cylinder connecting base 55 and can move up and down in the hole, the cylinder 52 is connected with an air compressor, and the air compressor is connected with a control system. When the pneumatic pressurizing mechanism 5 works, the air compressor is started through the control system, the air cylinder piston rod 53 is moved downwards by compressed air, a certain normal pressure is applied to the upper surface of the upper test platform 4, and the magnitude of the normal pressure can be adjusted through the control system.

As shown in fig. 6, the friction force collecting mechanism 6 includes a base 68, a cylindrical housing 64 is mounted on the base 68, bearings 67 are mounted on the upper and lower ends of the cylindrical housing 64, a screw 66 is mounted in the bearings 67, a slip ring 65 is mounted on the screw 66, one end of the slip ring 65 is connected to a connecting block 63, the connecting block 63 is connected to a tension sensor 61, one end of the tension sensor 61 is connected to a dowel bar 62, the dowel bar 62 is connected to an upper test platform 4, and the tension sensor 61 is connected to a data processing system. When the lower test platform 3 and the upper test platform 4 slide relatively, the friction force acquisition mechanism 6 can acquire the friction force value within the set stroke.

The whole working process is as follows: before measurement, the upper test piece 44 is weighed, a pressure value applied by the pneumatic pressurizing mechanism 5 is set, then the gravity of the upper test piece 44, the upper object loading table 41 and the set screw 43 is added to the normal pressure applied by the pneumatic pressurizing mechanism 5 to be used as a total normal pressure, and the total normal pressure value is input into the data processing system in advance. The lower trial 34 and the upper trial 44 are then mounted in sequence and the upper test platform 4 is mounted to the dowel bar 62 by means of the threaded joint 42. The motion stroke of the lower test platform 3 and the pressure value applied by the pneumatic pressurizing mechanism 5 are input into the control system, then the pneumatic pressurizing mechanism 5 acts, the air cylinder piston rod 53 is pressed down, and the upper surface of the upper test platform 4 applies pressure.

And then entering a formal test stage, sending a starting instruction by the control system to enable the servo motor 21 to drive the lower test platform 3 to move at a constant speed along a straight line, enabling the lower test platform 3 to rub the upper test platform 4, acquiring a friction value in a dynamic process by the friction force acquisition mechanism 6 and inputting the friction value into the data processing system, calculating the input data by the data processing system, and automatically outputting the friction coefficient value.

Claims

1. A stepless pressure regulating friction coefficient measuring instrument is characterized in that: the device comprises a rack (1), guide rails (8) arranged on two side edges of the rack (1), a power mechanism (2), a lower test platform (3), an upper test platform (4), a pneumatic pressurizing mechanism (5), a friction force acquisition mechanism (6), a distance sensor (7), a metal induction plate (9) and a computer provided with a control system and a data processing system; the testing device is characterized in that the power mechanism (2) is arranged at the bottom of a mounting groove of the rack (1), the lower testing platform (3) is arranged on the guide rail (8) and is positioned above the power mechanism (2), the upper testing platform (4) is arranged above the lower testing platform (3), the pneumatic pressurizing mechanism (5) is arranged above the lower testing platform (3) and the upper testing platform (4) and is fixed on bottom plates on two sides of the rack (1) through a support column (51), the friction force collecting mechanism (6) is arranged on the other side of the bottom of the rack (1), and the distance sensor (7) is arranged on the inner side wall of the mounting groove of the rack (1) and is positioned below the lower testing platform (3); the metal induction plate (9) is arranged on the lower surface of the lower test platform (3);

the power mechanism (2) is connected with the control system, the distance sensor (7) is connected with the control system, the pneumatic pressurizing mechanism (5) is connected with the control system, and the friction force acquisition mechanism (6) is connected with the data processing system.

2. The stepless pressure regulating friction coefficient measuring instrument according to claim 1, characterized in that: the power mechanism (2) comprises a servo motor (21), a motor support seat (22), a diaphragm coupling (23), a ball screw (24), a nut seat (25), a ball screw support seat (26), a baffle plate (27) and a support seat end cover (28); the servo motor (21) is installed on the motor supporting seat (22), the servo motor (21) is connected with the control system, the motor supporting seat (22) is installed on one side of the bottom of the installation groove of the rack (1), one end of the ball screw (24) is connected with one end of the servo motor (21) through the diaphragm coupling (23), the other end of the ball screw (24) is provided with the ball screw supporting seat (26), the outer side of the ball screw supporting seat (26) is provided with a baffle plate (27), and the baffle plate (27) is provided with a supporting seat end cover (28); the middle of the ball screw (24) is provided with a nut seat (25), and the nut seat (25) is connected with the lower surface of the lower test platform (3).

3. The stepless pressure regulating friction coefficient measuring instrument according to claim 1, characterized in that: the lower test platform (3) comprises a lower object stage (31), sliding blocks (35) are arranged on two sides of the bottom surface of the lower object stage (31), and the sliding blocks (35) are installed on the guide rails (8); a rectangular groove (33) is formed in the middle of the lower objective table (31), a clamping mechanism (32) is arranged on one side of the rectangular groove (33), and a fixing mechanism (36) is arranged on the other side of the rectangular groove (33); a lower test piece (34) is placed in the rectangular groove (33), and the lower test piece (34) is fixed through a clamping mechanism (32) and a fixing mechanism (36).

4. The stepless pressure regulating friction coefficient measuring instrument according to claim 1, characterized in that: go up test platform (4) and include objective table (41), be equipped with threaded connection head (42) on an end surface of going up objective table (41), the centre of going up objective table (41) is equipped with objective groove (45), place test piece (44) in objective groove (45), go up other three terminal surface installation holding screw (43) of objective table (41).

5. The stepless pressure regulating friction coefficient measuring instrument according to claim 1, characterized in that: pneumatic presser constructs (5) including cylinder connecting seat (55), the both sides of cylinder connecting seat (55) are equipped with pillar (51) and fix on the both sides bottom plate of frame (1) through pillar (51), install cylinder (52) on cylinder connecting seat (55), the lower extreme installation auxiliary motion connecting plate (56) of cylinder piston rod (53), auxiliary motion pole (54) are installed perpendicularly to the one end of auxiliary motion connecting plate (56), the hole that sets up on cylinder connecting seat (55) is passed perpendicularly to the one end of auxiliary motion pole (54), cylinder (52) are connected with air compressor, and air compressor is connected with control system.

6. The stepless pressure regulating friction coefficient measuring instrument according to claim 1, characterized in that: the friction force acquisition mechanism (6) comprises a base (68), a cylindrical shell (64) is installed on the base (68), a bearing (67) is installed on the upper end and the lower end of the cylindrical shell (64), a screw rod (66) is installed in the bearing (67), a sliding ring (65) is installed on the screw rod (66), one end of the sliding ring (65) is connected with a connecting block (63), the connecting block (63) is connected with a tension sensor (61), one end of the tension sensor (61) is connected with a dowel bar (62), the dowel bar (62) is connected with an upper test platform (4), and the tension sensor (61) is connected with a data processing system.

7. The stepless pressure regulating friction coefficient measuring instrument according to claim 1, characterized in that: the vertical distance between the metal induction plate (9) and the induction head of the distance sensor (7) is not more than 10 mm.

8. A stepless pressure regulating friction coefficient measuring instrument according to claim 3, characterized in that: the clamping mechanism (32) comprises a threaded seat (322), the threaded seat (322) is fixed on one side edge of the lower objective table (31), a screw rod (321) is arranged in the threaded seat (322), and one end of the screw rod (321) is provided with a clamp (323); the fixing mechanism (36) comprises two fixing blocks (363), the two fixing blocks (363) are fixed on the lower objective table (31) and located on two sides of the rectangular groove (33), a plurality of threaded holes (362) are formed in the fixing blocks (363), and fastening screws (361) are installed in the threaded holes (362).