Lead screw pair error compensation mechanism

Abstract

The present application relates to a kind of screw pair error compensation mechanism, including loading body, screw nut, screw, the connecting place of loading body and screw nut is provided with vertical compensation block and transverse compensation block, for generating the displacement amount of compensation in X direction and Y direction, to compensate the error between screw nut and screw in X direction and Y direction.The present application can digest the error in each direction of screw pair by vertical compensation block, transverse compensation block, loading link three compensation mechanisms, and stable support device is arranged on sensor connector and loading frame, so as to avoid the influence caused by mechanism deadweight to transmission system.

Description

TECHNICAL FIELD

[0001] The present application relates to a screw pair transmission system, in particular to an error compensation mechanism of a screw pair. BACKGROUND

[0002] Firstly, there are three common installation methods for screw pairs: both ends of the screw are fixed, and the fixed end bearings can simultaneously bear axial force; one end is fixed and the other end is free, and the fixed end bearings need to simultaneously bear axial force and radial force, which is suitable for short screw with small stroke or full closed loop working condition; one end is fixed and the other end is supported, and the fixed end simultaneously bears axial force and radial force, and the supported end only bears radial force and can have a small amount of axial floating, which can reduce or avoid the bending caused by the weight of the screw to a certain extent, and the thermal deformation of the screw can freely elongate to one end, which is widely used.

[0003] In addition, there are two factors that cause transmission errors of the screw pair: machining error and geometric installation error of the screw pair. Due to the deviation from the ideal position in the process of machining and installation, there is a certain inclination angle θy, θz between the screw (X axis) and Y axis and Z axis; at the same time, the screw is inevitably affected by the machining error and installation error of the guide rail matched with it during movement, so there are also rolling error εx (rolling angle), pitching error εy (pitching angle), and yawing error εz (yawing angle). These errors are often controlled by improving the installation accuracy of the screw pair adapter bracket and guide. SUMMARY

[0004] The present application provides an error compensation mechanism for a screw pair, which can compensate for the loss of the screw pair in terms of loading force, transmission efficiency, and use reliability caused by machining error and geometric installation error, and can be applied to three common screw pair installation methods, taking horizontal transmission as a model, and can be applied to vertical use of the screw pair by adjusting the guide direction.

[0005] To achieve the above-mentioned purpose, the technical scheme of the present application is: an error compensation mechanism for a screw pair, comprising a loading body, a screw nut, a screw, a vertical compensation block and a horizontal compensation block arranged at the connection between the loading body and the screw nut, for generating a compensation displacement in the X direction and the Y direction, thereby compensating for the error between the screw nut and the screw in the X direction and the Y direction.

[0006] Further, the vertical compensation block is composed of a vertical moving bracket and a vertical moving roller, the vertical moving bracket is connected with the loading link through a hinged bracket and connected with the screw nut through a flange mounting hole, for realizing the transmission of force between the loading frame and the screw pair; the vertical moving bracket is connected with the internal space of the horizontal compensation block through the vertical moving roller on both sides, and can vertically slide along the internal space of the horizontal compensation block.

[0007] Further, the two ends of the loading connecting rod are connected in the form of a spherical hinge, which can play the connecting role of a universal joint during force receiving.

[0008] Further, the loading connecting rod is connected with a tension and pressure sensor through a sensor connecting piece, and force is transmitted to the tension and pressure sensor.

[0009] Further, the sensor connecting piece comprises a connecting frame and two supporting rollers arranged at the left and right ends of the connecting frame, and the supporting rollers are connected with supporting guide grooves arranged on the loading body in a matched mode and are used for supporting the self weight of the compensation mechanism.

[0010] Further, the lateral compensation block is composed of a lateral moving bracket and a lateral moving roller, a middle cavity of the lateral moving bracket is used for mounting the vertical compensation block, the vertical compensation block takes the left and right walls of the frame as sliding tracks, and the lateral moving bracket is mounted in the interior of the loading body through the lateral moving roller which is installed to expose the upper and lower edges of the bracket; and the lateral moving bracket can realize lateral sliding in the interior space of the loading body.

[0011] The present application has the following beneficial effects:

[0012] The three compensation mechanisms of the vertical compensation block, the lateral compensation block and the loading connecting rod can digest the errors of the screw pair in all directions, and the stable supporting device is arranged on the sensor connecting piece and the loading frame, so that the influence of the self weight of the mechanism on the transmission system is also avoided.

[0013] The mechanism of the present application is not limited to be applied in the transmission system of the screw pair, and can be applied in various transmission mechanisms, such as linear guide rails, by configuring different guide devices and tool clamps. BRIEF DESCRIPTION OF DRAWINGS

[0014] Figure 1 is the error compensation mechanism of the screw pair of the present application;

[0015] Figure 2 is a vertical compensation block schematic diagram;

[0016] Figure 3 is a lateral compensation block schematic diagram;

[0017] Figure 4 is a loading connecting rod schematic diagram;

[0018] Figure 5 is a sensor connecting piece schematic diagram;

[0019] Figure 6 is a screw pair error compensation mechanism application example schematic diagram;

[0020] In the figure: 101. loading body, 102. vertical compensation block, 103. horizontal compensation block, 104. loading connecting rod, 105. sensor connecting piece, 201. vertical moving support, 202. vertical moving roller, 301. horizontal moving support, 302. horizontal moving roller, 501. connecting frame, 502. supporting roller, 503. loading device assembly, 504. linear guide rail, 505. linear guide rail slider, 506. driving device, 507. passive loading mechanism, 508. tension force sensor, 509. fixed rack, 510. screw rod support seat. DETAILED DESCRIPTION

[0021] The application will be further described below in combination with the drawings and examples.

[0022] The model takes the screw rod pair loading system as a prototype. Since the loading force is an axial force, if the loading force deviates from the axial direction due to machining and installation errors, it will lead to inaccurate measurement data and greatly reduce the service life of the measured screw rod pair.

[0023] As shown in Figure 1 , the screw rod pair error compensation mechanism of the application mainly includes: a loading body 101 connected with a screw rod nut, at the connection, a vertical compensation block 102 and a horizontal compensation block 103 are arranged, which can produce a certain displacement in the X direction and the Y direction, so as to compensate for the errors in the X direction and the Y direction between the nut and the screw rod.

[0024] As shown in Figure 2 , the vertical compensation block mainly consists of a vertical moving support 201 and a vertical moving roller 202. The articulated support on the support is connected with the loading connecting rod 104, the flange mounting hole is connected with the screw rod nut, realizing the transmission of force between the loading frame and the screw rod pair; the vertical moving roller is installed to expose the left and right edges of the support, and can vertically slide in the internal space of the horizontal compensation block 103.

[0025] As shown in Figure 3 , the horizontal compensation block mainly consists of a horizontal moving support 301 and a horizontal moving roller 302. The middle cavity of the support is used to install the vertical compensation block 102, so that it takes the left and right walls of the frame as the sliding track, and the horizontal moving support is installed in the interior of the loading body; the horizontal moving roller is installed to expose the upper and lower edges of the support, and realizes horizontal sliding in the internal space of the loading body 101.

[0026] As shown in Figure 4 , the two ends of the loading connecting rod 104 are connected in the form of a spherical hinge, which can play the connecting role of a universal joint during force receiving.

[0027] As shown in Figure 5As shown, one end of the sensor connecting piece 105 is connected with the loading connecting rod, and the other end is connected with the tension-compression force sensor to transmit the force to the tension-compression force sensor. The sensor connecting piece mainly comprises a connecting frame 501 and two left and right supporting rollers 502 which are matched with the supporting guide grooves arranged on the loading body 101 to support the self weight of the compensation mechanism.

[0028] Figure 6 An embodiment of the present application is shown, which is a lead screw pair loading force detection device.

[0029] The embodiment is a lead screw pair loading force test bench. The overall lead screw pair transmission mechanism is installed on a fixed bench 509. The lead screw is fixed on the bench by two head and tail lead screw support seats 510 at both ends. The nut is connected with the loading device assembly 503. The linear guide rail 504 is installed on the bench. The linear guide rail slider 505 is installed at the bottom of the loading body to realize movement guidance. The driving device 506 is connected with one end of the lead screw to drive the rotation of the lead screw, thereby driving the axial movement of the loading body. Meanwhile, the passive loading mechanism 507 is connected with the loading device assembly to counteract the movement generated by the driving device, thereby realizing the loading at the lead screw nut. The tension-compression force sensor 508 is arranged on the loading body to monitor the actual axial loading force in real time during the movement of the lead screw.

Claims

1. A lead screw pair error compensation mechanism, comprising a load body, a lead screw nut, a lead screw, characterized in that: The connecting part of the loading body and the screw nut is provided with vertical compensation blocks and horizontal compensation blocks for generating compensation displacement in X direction and Y direction, so as to compensate the error between the screw nut and the screw in X direction and Y direction. The vertical compensation block is composed of a vertical moving bracket and a vertical moving roller. The vertical moving bracket is connected with the loading link through a hinged bracket and connected with the screw nut through a flange mounting hole, for realizing the force transmission between the loading frame and the screw pair. The vertical moving bracket is connected with the inner space of the horizontal compensation block through the vertical moving roller on both sides, and can vertically slide along the inner space of the horizontal compensation block. The both ends of the loading link are connected in the form of spherical hinge, which can play the connecting role of universal joint in the force receiving process.

2. The lead screw pair error compensation mechanism of claim 1, wherein: The loading link is connected with the tension and compression force sensor through a sensor connecting piece, and the force is transmitted to the tension and compression force sensor.

3. The lead screw pair error compensation mechanism of claim 2, wherein: The sensor connecting piece comprises a connecting frame and two supporting rollers arranged on the left and right ends of the connecting frame. The supporting rollers are matched and connected with the supporting guide grooves arranged on the loading body, for supporting the self weight of the compensation mechanism.

4. The lead screw pair error compensation mechanism of claim 1, wherein: The horizontal compensation block is composed of a horizontal moving bracket and a horizontal moving roller. The middle cavity of the horizontal moving bracket is used for mounting the vertical compensation block, so that the vertical compensation block takes the left and right walls of the frame as sliding tracks. The horizontal moving bracket is mounted on the inside of the loading body through the horizontal moving roller exposed on the upper and lower edges of the bracket, and can realize horizontal sliding in the inner space of the loading body.

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