CN105527221A - Frictional force simulation generator - Google Patents

Abstract

The invention provides a friction simulation generating device, which is mainly composed of a lateral moving part mainly composed of a dynamic friction block and a pressure adjustment part mainly composed of a static friction block. The dynamic friction block is connected to the movable shaft through a coupler, and the two ends of the movable shaft are installed on the bearings with small friction force. Pulling the traction head can make the dynamic friction block move; the static friction block and the dynamic friction block are in close contact, which is applied to the dynamic friction block The upper pressure is adjusted through the adjustment handle; a displacement scaling member, an upper pressure piece, a lower pressure piece, an elastic component, a pressure sensor and a static friction piece fixing piece are arranged between the adjustment handle and the static friction piece; the dynamic friction coefficient and When the maximum static friction coefficient is known, by adjusting the pressure applied to the dynamic friction block, different friction motion characteristics can be generated on the tractor head, and the force of the tractor head is superimposed on the mechanical parts to be tested. The invention is mainly used to study the operating characteristics of mechanical components when they are affected by friction.

Description

A device for simulating friction force

technical field

The invention relates to a simulation device for mechanical properties between objects, in particular to a friction force simulation generation device.

Background technique

Two objects that are extruded and in contact with each other, the friction force generated when relative motion occurs is called sliding friction force, and the friction force produced when there is a relative motion tendency but remains relatively static is called static friction force. The magnitude of sliding friction is related to the normal pressure exerted by one object on another object and the coefficient of dynamic friction of the two contacting objects; the static friction varies with the magnitude of the external force, and its maximum value is called the maximum static friction, which can be obtained after measuring the coefficient of static friction have to. Many existing instruments can be used to measure friction or coefficient of friction, but specific conditions are often required in use, and it is difficult to use it for the friction characteristics of some equipment that has been installed on site. For valves in industrial processes, for example, measuring the friction between the valve stem and seal requires dismantling the valve, which is not allowed in practice. In addition, for a product designed for a specific function, the friction force between the moving components contained in it is basically determined on the new product, but as time goes by, the magnitude of the friction force may increase or decrease. Therefore, if researchers want to analyze the working characteristics of products under different friction forces, they need to measure the friction characteristics over a long period of time, which is time-consuming and laborious, and the working conditions are uncontrollable and not necessarily measurable.

Contents of the invention

The invention provides a friction force simulation generating device, which can simulate the mechanical characteristics of objects under different friction forces. The frictional force simulated by the device provided by the present invention can be superimposed on any force direction of the moving part of the measured object, so as to analyze the motion characteristics of the part under the influence of different frictional forces.

A friction simulation generating device provided by the present invention includes a static friction block and a dynamic friction block. The two friction blocks are extruded and contacted with each other. The quality is known, the surface characteristics are stable, and there are multiple friction blocks of different models made of different materials. The two ends of the dynamic friction block are respectively connected to the movable shaft through a coupler, and the movable shaft is connected to the bearing. By adjusting the position of the two bearing mounting seats on the guide rail, the stroke range of the movable shaft can be increased or decreased, so that the dynamic friction block The stroke can be adjusted accordingly. The pressure applied by the static friction block to the dynamic friction block can be adjusted. Under different pressure conditions, the dynamic friction block can produce different operating characteristics. The motion characteristics of the dynamic friction block are also affected by the friction force between the movable shaft and the bearing. The selection of the bearing should be based on minimizing the sliding friction force between the movable shaft and the bearing. At the same time, this sliding friction force can also be compensated on the ergonomic components.

A friction simulation generating device provided by the present invention includes a set of pressure regulating devices to change the pressure exerted by the static friction block on the dynamic friction block. The pressure regulating device mainly includes an adjusting handle, a displacement scaling member, an elastic component, a pressure sensor, a static friction block fixing piece and related auxiliary components. Rotating the adjustment handle drives the adjustment screw to rotate, and the adjustment screw is connected to the displacement scaling member, and the rotation displacement is scaled to drive the expansion screw to rotate. The rotation of the telescopic screw produces linear displacement in the same direction as its axis, thereby exerting pressure on the upper pressure member. The upper pressure piece is connected to the elastic assembly, the other end of the elastic assembly is connected to the lower pressure piece, and a pressure sensor is arranged between the lower pressure piece and the static friction block fixing piece. The elastic component will deform under the push of the upper pressure piece, and further scale the rotational displacement of the adjustment handle, so that the final pressure applied to the lower pressure piece can be adjusted within a wide range. The pressure sensor is used to detect the pressure applied to the fixed part of the static friction block. In conjunction with the data display in the man-machine operation component, the final pressure applied to the static friction block can be precisely set by adjusting the handle. The mass of the fixed part of the static friction block is known, and it is directly connected with the static friction block, and a fixing device is provided on the contact surface to ensure that the static friction block will not be displaced in the vertical direction of the contact surface.

A friction simulation generating device provided by the present invention includes a man-machine operation component, mainly composed of a microprocessor, an information input circuit, a pressure signal processing circuit, a communication interface circuit, a memory and a display circuit. The microprocessor is the core of the man-machine operation component, which performs calculation, storage, input and output processing on various electrical signals connected to it; the function of the information input circuit is to input the relevant component characteristic parameters of the present invention, such as: The quality of the friction block, the quality of the pressure sensor, the quality of the fixed part of the static friction block, and the friction compensation amount of the pulley, etc.; the pressure signal processing circuit processes the electrical signal from the pressure sensor, and then the information is output by the display circuit after being transformed by the microprocessor; the communication interface The circuit can be connected with other memory or control unit, which is used to input the compensation parameters required for friction calculation and output the experimental results; the memory is used to store some data and programs required for microprocessor operation; Some information such as status, parameters and work steps in the operation process are displayed.

The friction simulation generating device provided by the present invention also includes two pulleys and an external lead wire, one end of the external lead wire is connected to the traction head, and the other end is connected to the tested object. The function of the pulley is to convert the frictional force of the fixed direction of the dynamic friction block to different directions, and its installation position should not attenuate the frictional force of the dynamic friction block as a standard.

Description of drawings

Fig. 1 is a schematic front view of the main structure of the present invention.

Fig. 2 is a structural diagram of the man-machine operation component of the present invention.

[Description of attached symbols] 1. Adjusting handle; 2. Adjusting screw; 3. Fixing nut; 4. Displacement scaling member; 5. Bracket; 6. Upper pressure member; 7. Elastic component; 8. Lower pressure member; 9. Pressure sensor; 10. Static friction block fixture; 11. Static friction block; 12. Dynamic friction block; 13. Coupler; 14. Movable shaft; 15. Bearing; 16. Bearing mounting seat; 17. Guide rail; 18. Traction head ; 19. Pulley; 20. People and operating components; 21. Telescopic screw; 22. Base; 23. Traction line.

detailed description

In order to have a clearer understanding of the technical features, purposes and application methods of the present invention, the specific implementation manners of the present invention will be further described in conjunction with the accompanying drawings.

As shown in FIG. 1 , the friction simulation generating device provided by the present invention can be decomposed into a lateral moving part mainly composed of the dynamic friction block 12 , and a pressure regulating part mainly composed of the static friction block 11 . The two ends of the dynamic friction block 12 are respectively connected to the movable shaft 14 through the coupler 13. The correct installation of the coupler 13 can ensure that the axes of the movable friction block 12 and the movable shaft 14 are parallel or coincident, and the movable shaft 14 is connected to the bearing 15. One end of the movable shaft 14 is also provided with a traction head 18, the traction head 18 is connected to the traction line 23, and the traction line 23 can apply the frictional force motion characteristics to the tested experimental device through the pulley 19, and the pulley 19 is fixed on the base 22; the bearing 15 Bearing mounting seat 15 is provided, and bearing mounting seat 15 can move in the direction parallel to guide rail 17, and then be fixed on the base 22 after adjusting the position; static friction block 11 is connected to one side of static friction block fixing part 10, and static friction block fixing part 10 is on the other. One side is connected with the pressure sensor 9; the two ends of the elastic component 7 are connected with the upper pressure piece 6 and the lower pressure piece 8, and the other side of the lower pressure piece 8 is connected with the pressure sensor 9; the adjustment handle 1 is connected with the adjustment screw 2, and the fixed nut 3 is adjusted After the screw rod 2 is adjusted in place, it is used to fix it to prevent the adjustment screw rod 2 from shifting. The other end of the adjustment screw rod 2 is connected to the displacement zoom member 4, and the displacement zoom member 4 is connected to the bracket 5; Drive telescoping screw 21 to rotate; Displacement scaling member 4 is applied on telescopic screw 21 after scaling the rotational displacement of adjusting screw 2 to make it follow-up, and in an exemplary implementation of displacement scaling member 4, each member can be a group of gears Or a conveyor belt; the other end of the telescopic screw 21 is connected to the upper pressure piece 6, and the telescopic movement of the telescopic screw 21 will cause the upper pressure piece 6 to move in the same direction, and the pressure applied to the static friction block will change through force transmission.

As shown in Figure 2, the man-machine operation component 20 of the friction force simulation generating device provided by the present invention is composed of a microprocessor 101, an information input circuit 102, a pressure signal processing circuit 103, a communication interface circuit 104, a memory 105 and a display circuit 106 composition. The microprocessor 101 performs calculation processing on the input or output electrical signal, which can be a general-purpose computer (PC), a single-chip microcomputer, a programmable logic controller (PLC), an application-specific integrated circuit (ASIC), a programmable logic device (PLD) or Any combination of certain discrete components, etc. The information input circuit 102 is coupled to the microprocessor 101, through which various parameters and data can be manually input; the pressure signal processing circuit 103 sends the information of the pressure sensor 9 to the microprocessor 101 after processing; the communication interface circuit 104 is coupled to The microprocessor 101 is used to realize the import or export of data, and the memory 105 is used to store the programs and data required for calculation and processing; the display circuit 106 is also coupled to the microprocessor 101 to display the operating status and related parameters of the device .

The surfaces of the static friction block 11 and the dynamic friction block 12 in the friction simulation generation device provided by the present invention have a certain level of roughness, and different friction dynamic characteristics can be simulated by replacing friction blocks with different roughness levels.

In an exemplary embodiment of the present invention, the bearing 15 can be a linear bearing, and the sliding friction between the movable shaft 14 and the bearing 15 is very small, which is basically negligible compared to the friction between the dynamic friction block 12 and the static friction block 11 .

In an exemplary embodiment of the present invention, the steps of using the device are as follows:

S1. Select the desired type of dynamic friction block 12, and make it firmly connected with the movable shaft 14 by adjusting the coupling 13;

S2. Adjust the distance between the two bearing mounts 16 according to the usage conditions, and fix it after adjustment;

S3. Firmly connect the static friction block 11 and the static friction block fixing part 10, and input the quality parameters of the pressure sensor 9, the static friction block fixing part 10 and the static friction block 11 through the information input circuit 102 in the man-machine operation member 20;

S4. If the dynamic friction coefficient and the maximum static friction coefficient of the static friction block 11 and the dynamic friction block 12 are known, then directly jump to step S6, otherwise, rotate the adjustment handle 1 to make the static friction block 11 and the dynamic friction block 12 initially contact, and then continue to rotate in the same direction Adjust the handle 1, and observe the pressure data displayed by the display circuit 106 until its value is one greater than zero;

S5, connect the friction tester externally on the traction head 18, measure the coefficient of dynamic friction and the maximum coefficient of static friction between the static friction block 11 and the dynamic friction block 12;

S6. Input the friction compensation parameters between the bearing 15 and the movable shaft 14 through the information input circuit 102, and import various compensation data affecting the dynamic characteristics of friction through the communication interface circuit 104;

S7, according to the sliding friction calculation formula: sliding friction=dynamic friction coefficient multiplied by the positive pressure on the object, calculate the positive pressure value corresponding to the specific size of the sliding friction required for the experiment, and rotate the adjustment handle 1 to make the display circuit 106 display The pressure data of is equal to this value;

S8. Apply a specific dynamic characteristic of friction force to the measured object through the traction head 18 or the traction line 23, and if necessary, the pulley 19.

The above descriptions are only exemplary implementations of the present invention, and are not intended to limit the scope of the present invention. Any equivalent changes and modifications made by those skilled in the art without departing from the concepts and principles of the present invention, and the addition or reduction of certain device usage steps shall fall within the protection scope of the present invention.

Claims (12)

1. A friction simulation generating device, characterized in that: the device includes a moving part of a dynamic friction block and a pressure adjustment part of a static friction block, the two ends of the dynamic friction block are respectively connected to a coupler, and the coupler is connected to a movable shaft, which can be The moving shaft is connected to the bearing, and one end of the moving shaft is provided with a traction head. The traction head can be connected with the traction line, and the traction line applies the frictional force motion characteristics to the measured object through the pulley. The pulley is fixed on the base, and the bearing is installed on the bearing mounting seat. On the top, the bearing mounting seat can move in parallel on the guide rail. The static friction block is fixed by the static friction block fixing part. The other side of the static friction block fixing part is connected to the pressure sensor. Connect the pressure sensor, the adjustment handle is connected to the adjustment screw, and the other end of the adjustment screw is connected to the displacement zoom member. Through the displacement zoom member, the rotation of the adjustment screw drives the telescopic movement of the telescopic screw, and the other end of the telescopic screw is connected to the upper pressure piece. The movement in the same direction is generated and applied to the static friction block through force transmission, so that the static friction block generates pressure on the dynamic friction block. 2. A device for simulating frictional force, characterized in that the man-machine operation component included in the device is composed of a microprocessor, an information input circuit, a pressure signal processing circuit, a communication interface circuit, a memory and a display circuit. 3. A friction simulation generator as claimed in claim 1, characterized in that: the installation positions of the moving part of the dynamic friction block and the pressure adjustment part of the static friction block are perpendicular to each other, one of which is horizontal or vertical, and the other The relative is vertical or horizontal, and the so-called "static" and "moving" of the dynamic friction block and the static friction block are also relative. 4. A device for simulating friction force according to claim 1, characterized in that: said movable shaft has a smooth surface and low friction force. 5. A friction simulation generator as claimed in claim 1, characterized in that: the bearing friction is very small, and the distance between the two bearings can be adjusted within a certain stroke range. 6. A friction simulation generating device as claimed in claim 1, characterized in that: the coupler can firmly connect the dynamic friction block and the movable shaft, and the connected whole has strong rigidity, and in the direction of its axis No deformation occurs. 7. A device for simulating friction force as claimed in claim 1, characterized in that: the device is provided with a pulley, and the force characteristics of the traction head can be output to any direction without attenuation through the traction wire and the pulley. 8. A friction simulation generation device as claimed in claim 1, characterized in that: the displacement scaling mechanism scales the rotational displacement, and the elastic component scales the linear displacement, either of which can be used arbitrarily or at the same time . 9. A friction simulation generating device as claimed in claim 1, characterized in that: the quality of the dynamic friction block and the static friction block are known, the models can be changed, and the surface has a certain roughness, and the characteristics are stable. Surface friction does not change. 10. A device for simulating friction force as claimed in claim 1, characterized in that: the mass of the static friction block fixing part is known and the shape is changeable, and the static friction block cannot shake back and forth, up, down, left, and right after the static friction block is fixed. 11. A friction force simulation generator according to claim 1, characterized in that: one or both of a displacement zoom member and an elastic component, and a pressure sensor are arranged between the adjustment handle and the static friction block. 12. A friction simulation generating device as claimed in claim 2, characterized in that: said man-machine operation component can input relevant component quality parameters and friction compensation parameters, and the calculation algorithm of friction characteristics in the microprocessor is based on Table of various friction correction characteristics in memory.