CN110631824B - Bidirectional load testing device - Google Patents

Abstract

The invention provides a bidirectional load testing device, comprising: the device comprises a power output mechanism, a flexible traction assembly, a resistance loading mechanism, a sliding assembly and a central control device; the sliding component comprises a sliding table, a fixing unit, a pulling pressure sensor, a grating ruler, a position switch and a sliding rail; the flexible traction assembly comprises two groups of flexible traction units which are respectively arranged at two ends of the sliding table in the track direction and two ends of the resistance loading mechanism, so that an annular structure connected end to end is formed; the power output mechanism consists of a servo motor, a speed reduction transmission mechanism and a power output main shaft with a built-in torque sensor; the ball nut moves on the screw rod; the resistance loading mechanism transmits the generated load to the ball nut from the two directions of the sliding table through the flexible traction unit, and load data are obtained through the traction pressure sensor. The invention realizes the simulation test of the comprehensive working condition of the screw pair, improves the accuracy of the left-right movement test result of the screw pair, and is more convenient for design correction.

Description

A bidirectional load testing device

Technical Field

The invention relates to the technical field of testing rolling functional component products, in particular to a bidirectional load testing device.

Background Art

There are few load test equipment for rolling functional component products, especially linear actuators. Most of the existing running-in equipment is single-sided axial force running-in, with a single load mode, limited test functions, inability to simulate complex working conditions, and poor test structure accuracy.

Summary of the invention

The purpose of the present invention is to solve the above technical problems existing in the prior art and provide a bidirectional load testing device for load testing of a screw pair, wherein the screw pair comprises a screw rod and a ball nut sleeved on the screw rod and capable of moving along the axial direction of the screw rod, comprising:

Power output mechanism, flexible pulling assembly, resistance loading mechanism, sliding assembly and central control device;

The sliding assembly comprises a slide, a fixing unit and a tension and pressure sensor arranged on the slide for fixing the ball nut, and a slide rail arranged under the slide; the slide can move along the length direction of the slide rail;

The sliding assembly further comprises a grating ruler arranged at the side of the slide rail and parallel to the slide rail; the grating ruler is used to measure the movement accuracy of the ball nut along the screw rod;

The sliding assembly also includes a position switch, which is connected to the central control device and is used for system zeroing and stroke limitation;

The flexible pulling assembly includes two groups of flexible pulling units, which are respectively arranged at two ends of the track direction of the slide and at two ends of the resistance loading mechanism, so that the slide and the resistance loading mechanism form a ring structure connected end to end based on the two groups of flexible pulling units at the two ends;

The power output mechanism comprises a servo motor, a reduction transmission mechanism and a power output spindle with a built-in torque sensor; wherein the servo motor is connected to the power output spindle through the reduction transmission mechanism, and the rotational power is transmitted from the power output spindle to the screw rod through the reduction transmission mechanism;

The ball nut moves on the screw rod; the resistance loading mechanism transmits the generated load from the slide to the ball nut in both directions through the flexible pulling unit, and obtains load data through the tension and pressure sensor.

The power output spindle reduction transmission mechanism is preferably such that each of the two sides of the bidirectional load testing device is provided with two parallel flexible pulling units, both of which are connected to one end of the slide and one end of the resistance loading mechanism.

Preferably, the slide table comprises a front stage and a back stage sequentially arranged along the length direction of the slide rail, and the front stage and the back stage are connected as a whole through two tension and pressure sensors, so as to obtain load data between the front stage and the back stage through the tension and pressure sensors;

The fixing unit is arranged on the front stage.

Preferably, the fixing unit comprises two clamps disposed on the front stage and facing each other, and a pin passing through the clamps for connecting and fixing the two clamps;

The front desk is provided with two movable grooves on the same horizontal line; the clamps can move toward or away from each other along the movable grooves;

The clamp position is provided with a clamping groove for clamping the ball nut, so that the ball nut can be clamped by the two clamps based on the clamping groove, and the ball nut can be fixed between the two clamps by shortening the distance between the clamps through the pin shaft.

Preferably, the resistance loading mechanism comprises a clutch sliding frame, a clutch, a brake plate and an optical axis guide rail;

The clutch is arranged in the clutch sliding frame;

The optical axis guide rail is arranged through the clutch sliding frame, so that the clutch sliding frame can move along the length direction of the optical axis guide rail;

Both ends of the clutch sliding frame are respectively connected to one of the flexible pulling units;

The clutch and the brake plate generate a load based on resistance caused by friction, and the load is transmitted to the ball nut through the flexible pulling unit.

Preferably, the clutch comprises a clutch mounting plate disposed on the clutch sliding frame, and two sets of clutch moving mechanisms symmetrically arranged on the clutch mounting plate;

The clutch moving mechanism includes a hydraulic mounting seat and a friction plate connected to the hydraulic mounting seat;

The two friction plates can move towards each other under the drive of the hydraulic mounting seat;

The brake plate is arranged between the two friction plates, so that the two friction plates can abut against the brake plate to generate friction resistance after moving toward each other.

Preferably, the bidirectional load testing device is provided with a base mounting plate;

Wherein, the optical axis guide rail is fixed to the base mounting plate through mounting seats at both ends in the length direction; and the brake plate is arranged parallel to the optical axis guide rail and is fixed to the base mounting plate through clamping seats at both ends.

Preferably, two sliding slots are provided at both ends of the clutch on the clutch sliding frame, and a straight bearing is provided at each sliding slot;

The resistance loading mechanism is provided with two optical axis guide rails, and each of the optical axis guide rails is passed through a corresponding linear bearing.

Preferably, it also includes a support frame;

The support frame includes a platform at the upper end supported by a column and a base mounting plate at the lower end arranged parallel to the platform;

The power output mechanism and the sliding assembly are fixedly arranged on the upper end surface of the platform; the resistance loading mechanism is arranged on the base mounting plate;

The central control device is connected to the platform, and is electrically connected to the power output mechanism, the resistance loading mechanism and the tension and pressure sensor.

Preferably, the support frame further comprises an electrical installation platform disposed in the middle;

Both ends of the electrical installation platform parallel to the moving direction of the slide rail are provided with lower supporting fixed pulleys;

Both ends of the upper end of the platform are provided with upper supporting fixed pulleys;

The flexible pulling unit of the flexible pulling assembly is arranged on the upper supporting fixed pulley and the lower supporting fixed pulley, and can move under the limit of the upper supporting fixed pulley and the lower supporting fixed pulley under the drive of the power output mechanism.

The present invention provides a bidirectional load testing device, comprising: a power output mechanism, a flexible pulling component, a resistance loading mechanism, a sliding component and a central control device; the sliding component comprises a slide, a fixing unit and a tension pressure sensor arranged on the slide for fixing a ball nut, and a slide rail arranged under the slide; the slide can move along the length direction of the slide rail; the flexible pulling component comprises two groups of flexible pulling units, which are respectively arranged at two ends of the track direction of the slide and at two ends of the resistance loading mechanism, so that the slide and the resistance loading mechanism form a ring structure based on the two groups of flexible pulling units at the two ends; the power output spindle of the power output mechanism is composed of a servo motor, a reduction transmission mechanism and a power output spindle with a built-in torque sensor, which is used to output rotational power to a screw rod; the ball nut moves on the screw rod; the resistance loading mechanism transmits the generated load from the two directions of the slide to the ball nut through the flexible pulling unit, and obtains load data through the tension pressure sensor.

The present invention fixes the ball nut by a sliding assembly, and has a power output mechanism to output power to the screw rod so that the ball nut moves along the screw rod, thereby driving the flexible pulling units at both ends to move, and generating a load through a resistance loading mechanism, which is transmitted to the ball nut in two directions through the flexible pulling units at both ends, thereby improving the accuracy of the left and right movement test results of the screw test, and at the same time making it easier to design and modify and simulating complex working conditions.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 is a schematic diagram of the overall structure of a bidirectional load testing device provided in an embodiment;

FIG2 is a left schematic view of a bidirectional load testing device provided in an embodiment;

FIG3 is a schematic top view of a bidirectional load testing device provided in an embodiment;

4 is a schematic structural diagram of a power output mechanism of a bidirectional load testing device provided in an embodiment;

5 is a schematic structural diagram of a sliding assembly of a bidirectional load testing device provided in an embodiment;

6 is a schematic structural diagram of a flexible pulling assembly of a bidirectional load testing device provided in an embodiment;

7 is a schematic structural diagram of a resistance loading mechanism of a bidirectional load testing device provided in an embodiment;

8 is a schematic structural diagram of a clutch in a resistance loading mechanism of a bidirectional load testing device provided in an embodiment;

FIG. 9 is a schematic diagram of a partially enlarged structure of a clutch in a resistance loading mechanism of a bidirectional load testing device provided in an embodiment.

Reference numerals:

The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings.

DETAILED DESCRIPTION

Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.

In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

The present invention will be further described in detail below through specific implementation modes in conjunction with the accompanying drawings.

Example:

Referring to FIGS. 1-9 , this embodiment provides a bidirectional load testing device, which is applied to a load test of a lead screw pair 6. The lead screw pair 6 includes a lead screw 61, and a ball nut 62 sleeved on the lead screw 61 and capable of axially moving along the lead screw 61, including:

Power output mechanism 1, flexible pulling component 2, resistance loading mechanism 3, sliding component 4 and central control device 7;

The sliding assembly 4 includes a slide 41, a fixing unit 42 and a tension and pressure sensor 43 disposed on the slide 41 for fixing the ball nut 62, and a slide rail 44 disposed under the slide 41; the slide 41 can move along the length direction of the slide rail 44;

The sliding assembly 4 further includes a grating ruler 45 disposed at the side of the slide rail 44 and parallel to the slide rail 44; the grating ruler 45 is used to measure the movement accuracy of the ball nut 62 along the screw rod 61;

The sliding assembly 4 also includes a position switch 46, which is connected to the central control device 7 and is used for system zeroing and stroke limiting; the flexible pulling assembly 2 includes two groups of flexible pulling units 21, which are respectively arranged at the two ends of the track direction of the slide 41 and the two ends of the resistance loading mechanism 3, so that the slide 41 and the resistance loading mechanism 3 form a ring structure connected end to end based on the two groups of flexible pulling units 21 at the two ends;

The power output mechanism 1 includes a servo motor 13, a reduction transmission mechanism 12 and a power output main shaft 11 with a built-in torque sensor; wherein the servo motor 13 is connected to the power output main shaft 11 through the reduction transmission mechanism 12, and the rotational power is transmitted from the power output main shaft 11 to the screw rod 61 through the reduction transmission mechanism 12;

The ball nut 62 moves on the screw rod 61 ; the resistance loading mechanism 3 transmits the generated load from the slide 41 to the ball nut 62 in both directions through the flexible pulling unit 21 , and obtains load data through the tension pressure sensor 43 .

The power output spindle 11 reduction transmission mechanism 12 As mentioned above, the power output mechanism 1 is used to output the power in the rotation direction to the screw 61. Specifically, it can include the power output spindle 11, the servo motor 13 and the reduction transmission mechanism 12. Among them, the reduction transmission mechanism 12 is connected to the power output spindle 11 to connect with the screw 61 to provide power, and the other end of the reduction transmission mechanism 12 is connected to the servo motor 13. The reduction transmission mechanism 12 can be a belt; so that after the servo motor 13 is started, the power is transmitted to the reduction mechanism 14 through the belt, and the reduction mechanism 14 is then output to the connected screw 61 by the power spindle at the front end. In addition, the screw 61 and the power spindle can be connected by an ER32 quick chuck, so as to facilitate the installation and disassembly operation. As mentioned above, the flexible pulling assembly 2 includes two groups of flexible pulling units 21, wherein each group of flexible pulling units 21 can be a group of chains, or other pulling mechanisms with flexible properties. In addition, it can also be a flexible rope such as a synchronous belt or a steel cable.

As mentioned above, the flexible pulling component 2 may include two groups of flexible pulling units 21, each group may be provided with two chains, that is, at both ends of the sliding component 4 and the two ends of the resistance loading mechanism 3, two chains are provided on each side, thereby further improving stability and improving the accuracy of the test results.

As mentioned above, the resistance loading mechanism 3 is used to generate resistance, which may include but is not limited to hydraulic loading and electromagnetic clutch loading to generate friction resistance, and is a mechanism for increasing the axial load of the screw pair 6 .

As mentioned above, the sliding assembly 4 includes a slide 41, a fixing unit 42 and a tension and pressure sensor 43. A slide rail 44 is provided under the slide 41; the slide 41 can move along the length direction of the slide rail 44; the slide rail 44 can be a linear motion actuator, such as a linear module.

As described above, the power resistance loading mechanism 3 and the sliding assembly 4 are connected end to end through the chain, so as to achieve bidirectional load application to the ball nut 62, which improves the accuracy of the test compared to the test equipment that applies load in a single direction.

There is also a position switch 46, which is connected to the central control device 7 and is arranged on the upper platform 52 for system zeroing and stroke limitation.

In addition, a grating ruler 45 (, which is located between the sliding assembly 4 and the base, can be provided on the side of the slide rail 44 and parallel to the slide rail 44, and can measure the positioning accuracy and repeatability of the lead screw pair 6. It should be noted that the grating ruler 45, also known as the grating ruler 45 displacement sensor (grating ruler 45 sensor), is a measurement feedback device that works on the optical principle of a grating. The grating ruler 45 is often used in the closed-loop servo system of a CNC machine tool and can be used to detect linear displacement or angular displacement. The measured output signal is a digital pulse, which has the characteristics of a large detection range, high detection accuracy and fast response speed. The power output mechanism 1 includes a servo motor 13, a reduction transmission mechanism 12 and a power output spindle 11 with a built-in torque sensor; a torque sensor is also provided in the power output spindle 11 for obtaining relevant torque data. The reduction transmission mechanism 12 can be driven by a belt drive, that is, the rotational power output by the servo motor 13 is output to the spindle after deceleration through a conveyor belt and large and small wheels.

As mentioned above, the position switch 46 is electrically connected to the PLC (central control device 7) and is used to feed back the position signal to the central control device 7. On the one hand, it serves as a reference zero point for movement, and on the other hand, it serves as a safety limit formed by positive and negative. In addition, the position switch 46 can also be used for return movement.

In this embodiment, the grating ruler 45 can be connected to the central control device 7 and feed back detection data to the central control device 7 .

In this embodiment, the ball nut 62 is fixed by the sliding assembly 4, and the power output mechanism 1 outputs power to the screw 61 to make the ball nut 62 move along the screw 61, driving the flexible pulling units 21 at both ends to move, and the load is generated by the resistance loading mechanism 3 so that the flexible pulling units 21 at both ends are transmitted to the ball nut 62 in two directions, thereby improving the accuracy of the left and right movement test results of the screw test, and at the same time, it is more convenient to design and modify and can simulate complex working conditions. .

Furthermore, each of the two sides of the bidirectional load testing device is provided with two parallel flexible pulling units 21 , both of which are connected to one end of the slide 41 and one end of the resistance loading mechanism 3 .

Furthermore, the slide 41 includes a front stage 411 and a back stage 412 sequentially arranged along the length direction of the slide rail 44, and the front stage 411 and the back stage 412 are connected as a whole through two tension and pressure sensors 43, so as to obtain load data between the front stage 411 and the back stage 412 through the tension and pressure sensors 43;

The fixing unit 42 is disposed on the front desk 411 .

As mentioned above, the front stage 411 and the back stage 412 of the slide 41 are two independent mechanisms, which are connected into one by a pressure sensor arranged in the middle. A sensor mounting seat is arranged at the corresponding position of the front stage 411 and the back stage 412, and the pressure sensor in the middle is fixedly connected based on the two sensor mounting seats.

A fixing device is provided on the front stage 411 for fixing the ball nut 62, and the front stage 411 and the back stage 412 are connected with chains respectively. Driven by the servo motor 13 of the power output mechanism 1, the front stage 411 moves and pulls the back stage 412 to move synchronously. At this time, after the resistance loading mechanism 3 is turned on to generate friction resistance, it is transmitted between the front stage 411 and the back stage 412 through the chain, so that the load data can be obtained through the sensor.

Preferably, the fixing unit 42 includes two clamps 421 disposed on the front desk 411 and facing each other, and a pin 422 passing through the clamps 421 to connect and fix the two clamps 421;

Can move along the vertical direction of the length of the slide rail 44

The front desk 411 is provided with two moving grooves 411a on the same horizontal line; the clamp 421 can move toward or away from each other along the moving grooves 411a;

The clamp 421 is provided with a clamping groove 421a for clamping the ball nut 62, so that the ball nut 62 can be clamped by the two clamps 421 based on the clamping groove 421a, and the ball nut 62 can be fixed between the two clamps 421 by shortening the distance between the clamps 421 through the pin 422.

As mentioned above, the front desk 411 is provided with a moving groove 411a, which is connected to the clamp 421 of the fixing unit 42, and the clamp 421 can slide toward each other along the moving groove 411a, so that the ball nut 62 with the clamping groove 421a fixed between the two clamps 421 sliding toward each other can be clamped, and the distance between the two clamps 421 can be further tightened by the pin 422, so that the ball nut 62 can be fixed. The center self-positioning of the ball nut 62 is achieved through the clamp 421.

Furthermore, the resistance loading mechanism 3 includes a clutch sliding frame 31, a clutch 32, a brake plate 33 and an optical axis guide rail 34;

The clutch 32 is disposed in the clutch sliding frame 31;

The optical axis guide rail 34 is disposed through the clutch sliding frame 31 so that the clutch sliding frame 31 can move along the length direction of the optical axis guide rail 34;

Both ends of the clutch sliding frame 31 are connected to the flexible pulling unit 21 respectively;

The clutch 32 and the brake plate 33 generate a load based on resistance caused by friction, and the load is transmitted to the ball nut 62 through the flexible pulling unit 21 .

As mentioned above, the flexible pulling unit 21 is respectively connected to the two ends of the clutch sliding frame 31. The clutch sliding frame 31 may include a clutch 32 installation area in the middle and optical axis positions at both ends for connecting with the chain; the optical axis position may be an optical axis hole, in which an optical axis guide rail 34 is arranged, and two optical axis guide rails 34 are arranged along the length direction of the slide rail 44, and are arranged at both ends of the clutch 32 in the middle, so that the clutch sliding frame 31 can reciprocate along the length direction of the optical axis guide rail 34.

At the lower end of the clutch sliding frame 31, at a position corresponding to the clutch 32, at least one brake plate 33 can be provided, so that the clutch 32 and the brake plate 33 can cooperate with each other to generate sliding friction between the two, so that the sliding friction generated by the brake plate 33 forms resistance as a load, which is transmitted to the ball nut 62 through the chains at both ends to realize load testing.

Preferably, the clutch 32 comprises a clutch mounting plate 321 disposed on the clutch sliding frame 31, and two sets of clutch moving mechanisms 322 symmetrically arranged on the clutch mounting plate 321;

The clutch moving mechanism 322 includes a hydraulic mounting seat 3221 and a friction plate 3222 connected to the hydraulic mounting seat 3221;

The two friction plates 3222 can move towards each other under the drive of the hydraulic mounting seat 3221;

The brake plate 33 is disposed between the two friction plates 3222 so that the two friction plates 3222 can abut against the brake plate 33 to generate friction resistance after moving toward each other.

As mentioned above, the clutch 32 is provided with a clutch mounting plate 321, on which two sets of clutch moving mechanisms 322 are axially symmetrically provided. The clutch moving mechanisms 322 can be hydraulically driven or electromagnetically driven. In this embodiment, it is a hydraulic clutch moving mechanism 322. Hydraulic clutch loading can perform ultra-heavy load tests on large heavy-loaded screws, and the equipment is small in size.

Specifically, it includes an outer hydraulic mounting seat 3221 and a friction plate 3222 that can be connected to the mounting seat. The two friction plates 3222 are arranged opposite to each other, and the space between them is the corresponding brake plate 33. The oil pressure of the hydraulic clutch 32 is controlled by the servo hydraulic valve, so that the two friction plates 3222 move toward each other and resist the brake plate 33 to generate friction resistance, and further digital precision adjustment can be performed through feedback from the pull pressure sensor 43.

Preferably, the bidirectional load testing device is provided with a base mounting plate 54;

The optical axis guide rail 34 is fixed to the base mounting plate 54 via mounting seats at both ends in the length direction; and the brake plate 33 is arranged parallel to the optical axis guide rail 34 and fixed to the base mounting plate 54 via clamping seats at both ends.

The optical axis guide rail 34 is a limit rail 44 that enables the clutch slide frame 31 to reciprocate in a limited area. The specific moving stroke length on the optical axis guide rail 34 can match the slide rail 44 at the lower end of the slide table 41 of the slide assembly 4, so that the two can have the same moving stroke.

Preferably, two sliding slots 311 are provided at both ends of the clutch 32 on the clutch sliding frame 31, and a straight bearing 312 is provided at each sliding slot 311;

The resistance loading mechanism 3 is provided with two optical axis guide rails 34 , and each of the optical axis guide rails 34 is passed through a corresponding linear bearing 312 .

Preferably, it also includes a support frame 5;

The support frame 5 includes a platform 52 at the upper end supported by a column 51 and a base mounting plate 54 at the lower end arranged parallel to the platform 52;

The power output mechanism 1 and the sliding assembly 4 are fixedly mounted on the upper end surface of the platform 52; the resistance loading mechanism 3 is mounted on the base mounting plate 54;

The central control device 7 is connected to the platform 52 , and is electrically connected to the power output mechanism 1 , the resistance loading mechanism 3 and the tension and pressure sensor 43 .

The support frame 5 is used to fix and support the entire test device. Specifically, it can be supported by four columns 51 and multiple tables from top to bottom, wherein the upper end can be provided with a platform 52 and the lower end can be provided with a base mounting plate 54.

The power output mechanism 1 and the sliding assembly 4 are fixed on the platform 52 ; and the resistance loading mechanism 3 is provided on the base mounting plate 54 .

The central control device 7 is used for the operator to input data, and can be a computer for data acquisition, analysis, and obtaining the operator's operating instructions. It can include but is not limited to: a processor, a mainboard, a touch screen, and a port, which is connected to the sensor and the related power output mechanism 1 and the resistance loading mechanism 3 through the port, so as to realize the data acquisition and control of the related equipment according to the instructions.

Preferably, the support frame 5 further comprises an electrical installation platform 53 disposed in the middle;

Both ends of the electrical installation platform 53 parallel to the moving direction of the slide rail 44 are provided with lower supporting fixed pulleys 531;

Both ends of the upper end of the platform 52 are provided with upper support fixed pulleys 521;

The flexible pulling unit 21 of the flexible pulling assembly 2 is arranged on the upper supporting fixed pulley 521 and the lower supporting fixed pulley 531 , and can move under the limit of the upper supporting fixed pulley 521 and the lower supporting fixed pulley 531 under the drive of the power output mechanism 1 .

An electrical installation platform 53 is also provided in the middle, on which a lower supporting fixed pulley 531 is provided, which cooperates with the upper supporting fixed pulley 521 on the upper platform 52, so that the two groups of chains arranged on both sides can be supported and tightened by the fixed pulleys respectively, so that under the drive of the servo motor 13 of the power output mechanism 1, the chain can move along the limit of the fixed pulley and transfer the load.

In addition, a position sensor, an infrared temperature sensor, a vibration sensor, etc. can also be provided, all of which are electrically connected to the main console, so as to achieve the acquisition and calculation of different data, and further test multiple projects.

Specifically, the test device provided in this embodiment can perform the following tests:

1) Comprehensive test of variable load condition simulation

This structure can be used to simulate the actual working conditions through the servo hydraulic valve and the tension pressure sensor 43 to perform variable load testing. The axial load can be adjusted in one direction, two directions, and in size according to the needs.

2) Torque test

The power output spindle 11 with a built-in torque sensor can monitor the final real-time torque in real time and is used to measure the rated torque, maximum torque and life of the screw pair 6.

3) Load test

The tension and pressure sensor 43 is located inside the sliding assembly 4 and can monitor the actual axial load in real time and test the axial rated load, maximum load and life of the lead screw pair 6.

4) Positioning accuracy and repeatability

The grating ruler 45 is located between the sliding assembly 4 and the base, and can measure the positioning accuracy and repeatability of the lead screw pair 6 .

5) Transmission efficiency test

The data collected by the tension and pressure sensor 43 and the torque sensor can be used by the host computer to calculate the transmission efficiency of the screw pair 6, and the design of the screw pair 6 can be optimized according to the geometric accuracy of the screw size.

6) Other tests

According to needs, noise, temperature, deformation and other sensors can be added to the structure to carry out relevant performance tests of the screw pair 6, with multi-function integration to inspect or optimize the screw pair 6 product.

In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "an example", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

The above contents are further detailed descriptions of the present invention in combination with specific implementation methods, and it cannot be determined that the specific implementation of the present invention is limited to these descriptions. For ordinary technicians in the technical field to which the present invention belongs, several simple deductions or substitutions can be made without departing from the concept of the present invention.

Claims (10)

1. A bidirectional load testing device, used for load testing of a screw pair, wherein the screw pair comprises a screw rod and a ball nut sleeved on the screw rod and movable along the axial direction of the screw rod, characterized in that it comprises: Power output mechanism, flexible pulling assembly, resistance loading mechanism, sliding assembly and central control device; The sliding assembly comprises a slide, a fixing unit and a tension and pressure sensor arranged on the slide for fixing the ball nut, and a slide rail arranged under the slide; the slide can move along the length direction of the slide rail; The sliding assembly further comprises a grating ruler arranged at the side of the slide rail and parallel to the slide rail; the grating ruler is used to measure the movement accuracy of the ball nut along the lead screw; The sliding assembly also includes a position switch, which is connected to the central control device and is used for system zeroing and stroke limitation; The flexible pulling assembly includes two groups of flexible pulling units, which are respectively arranged at two ends of the track direction of the slide and at two ends of the resistance loading mechanism, so that the slide and the resistance loading mechanism form a ring structure connected end to end based on the two groups of flexible pulling units at the two ends; The power output mechanism comprises a servo motor, a reduction transmission mechanism and a power output spindle with a built-in torque sensor; wherein the servo motor is connected to the power output spindle through the reduction transmission mechanism, and the rotational power is transmitted from the power output spindle to the screw rod through the reduction transmission mechanism; The ball nut moves on the screw rod; the resistance loading mechanism transmits the generated load from the slide to the ball nut in both directions through the flexible pulling unit, and obtains load data through the tension and pressure sensor. 2. The bidirectional load testing device as described in claim 1 is characterized in that each of the two sides of the bidirectional load testing device is provided with two parallel flexible pulling units; both are connected to one end of the slide and one end of the resistance loading mechanism. 3. The bidirectional load testing device according to claim 1, characterized in that the slide table comprises a front stage and a back stage sequentially arranged along the length direction of the slide rail, and the front stage and the back stage are connected into a whole through two tension and pressure sensors, so as to obtain the load data between the front stage and the back stage through the tension and pressure sensors; The fixing unit is arranged on the front desk; The flexible pulling unit is respectively connected to the front end of the front stage and an end of the back stage which is different from the front stage. 4. The bidirectional load testing device according to claim 3, characterized in that the fixing unit comprises two clamps arranged on the front stage and facing each other, and a pin passing through the clamps for connecting and fixing the two clamps; The front desk is provided with two movable grooves on the same horizontal line; the clamps can move toward or away from each other along the movable grooves; The clamp position is provided with a clamping groove for clamping the ball nut, so that the ball nut can be clamped by the two clamps based on the clamping groove, and the ball nut can be fixed between the two clamps by shortening the distance between the clamps through the pin shaft. 5. The bidirectional load testing device according to claim 1, characterized in that the resistance loading mechanism comprises a clutch sliding frame, a clutch, a brake plate and an optical axis guide rail; The clutch is arranged in the clutch sliding frame; The optical axis guide rail is arranged through the clutch sliding frame, so that the clutch sliding frame can move along the length direction of the optical axis guide rail; Both ends of the clutch sliding frame are respectively connected to one of the flexible pulling units; The clutch and the brake plate generate a load based on resistance caused by friction, and the load is transmitted to the ball nut through the flexible pulling unit. 6. The bidirectional load testing device according to claim 5, characterized in that the clutch comprises a clutch mounting plate arranged on the clutch sliding frame, and two sets of clutch moving mechanisms symmetrically arranged on the clutch mounting plate; The clutch moving mechanism includes a hydraulic mounting seat and a friction plate connected to the hydraulic mounting seat; The two friction plates can move towards each other under the drive of the hydraulic mounting seat; The brake plate is arranged between the two friction plates, so that the two friction plates can abut against the brake plate to generate friction resistance after moving toward each other. 7. The bidirectional load testing device according to claim 6, characterized in that the bidirectional load testing device is provided with a base mounting plate; Wherein, the optical axis guide rail is fixed to the base mounting plate through mounting seats at both ends in the length direction; and the brake plate is arranged parallel to the optical axis guide rail and is fixed to the base mounting plate through clamping seats at both ends. 8. The bidirectional load testing device according to claim 7, characterized in that: Two sliding slots are provided at both ends of the clutch on the clutch sliding frame, and a straight bearing is provided at each sliding slot; The resistance loading mechanism is provided with two optical axis guide rails, and each of the optical axis guide rails is passed through a corresponding linear bearing. 9. The bidirectional load testing device according to claim 1, further comprising a support frame; The support frame includes a platform at the upper end supported by a column and a base mounting plate at the lower end arranged parallel to the platform; The power output mechanism and the sliding assembly are fixedly arranged on the upper end surface of the platform; the resistance loading mechanism is arranged on the base mounting plate; The central control device is connected to the platform, and is electrically connected to the power output mechanism, the resistance loading mechanism and the tension and pressure sensor. 10. The bidirectional load testing device according to claim 9, characterized in that the support frame further comprises an electrical installation platform disposed in the middle; Both ends of the electrical installation platform parallel to the moving direction of the slide rail are provided with lower supporting fixed pulleys; Both ends of the upper end of the platform are provided with upper supporting fixed pulleys; The flexible pulling unit of the flexible pulling assembly is arranged on the upper supporting fixed pulley and the lower supporting fixed pulley, and can move under the limit of the upper supporting fixed pulley and the lower supporting fixed pulley under the drive of the power output mechanism.