CN-121989058-A - Self-adaptive braking mechanism for workbench of horizontal machining center

CN121989058ACN 121989058 ACN121989058 ACN 121989058ACN-121989058-A

Abstract

The application discloses a workbench self-adaptive braking mechanism of a horizontal machining center, which relates to the technical field of horizontal machining centers and comprises a braking component, a heat dissipation component and an intelligent control component, wherein the braking component comprises a braking disc which rotates synchronously with a workbench main shaft and an opposite caliper which applies friction braking to the braking disc, the heat dissipation component comprises a centrifugal fan and a variable guide air duct, the variable guide air duct is arranged on an air outlet path of the centrifugal fan and is used for guiding cooling air flow to a friction surface of the braking disc.

Inventors

WU XINGFEI
HAO JINGYUAN
Deng Juehua
DENG GUANGYA
Deng Songya
Wu Daohan

Assignees

北京博鲁斯潘精密机床有限公司

Dates

Publication Date: 20260508
Application Date: 20260310

Claims (8)

1. A horizontal machining center workstation self-adaptation brake mechanism, its characterized in that includes: A brake assembly comprising a brake disc (1) rotating synchronously with a table spindle and an opposed caliper (2) applying a friction brake to the brake disc (1); The cooling assembly comprises a centrifugal fan (3) and a variable guide air duct (4), the variable guide air duct (4) is arranged on an air outlet path of the centrifugal fan (3), and the variable guide air duct (4) is used for guiding cooling air flow to a friction surface of the brake disc (1); The heat storage assembly comprises a phase change heat storage unit (5) integrated inside the brake disc (1); The intelligent control assembly comprises a controller, a rotating speed sensor for detecting the rotating speed of the brake disc (1) and a temperature sensing unit for detecting the equivalent temperature of the phase-change heat storage unit (5); the controller is respectively connected with the rotating speed sensor, the temperature sensing unit, the centrifugal fan (3) and the driving unit of the variable guide air duct (4) in a signal manner; the controller is configured to perform cooperative closed loop control of the power of the centrifugal fan (3) and the guiding angle of the variable guiding air duct (4) based on feedback signals of the rotational speed sensor and the temperature sensing unit.
2. The adaptive braking mechanism for a horizontal machining center workbench according to claim 1, wherein the variable guide air duct (4) comprises an annular guide cover (41) and a plurality of adjustable guide vanes (42) arranged in the annular guide cover, the adjustable guide vanes (42) are uniformly distributed along the circumferential direction of the annular guide cover (41) and are respectively connected to the annular guide cover (41) through shape memory alloy actuators, and the shape memory alloy actuators deform under the current control of the controller so as to drive the corresponding adjustable guide vanes (42) to rotate around the rotating shafts of the adjustable guide vanes, so that the air outlet angle and the air flow coverage area of the air duct are changed.
3. The self-adaptive braking mechanism for a horizontal machining center workbench according to claim 2, wherein a circle of vortex generating structures (411) are arranged at the edge of the air outlet of the annular air guide sleeve (41), and the vortex generating structures (411) are composed of a plurality of micro-vortex fins which form an included angle of 15-60 degrees with the plane of the air outlet and are alternately inclined along the circumferential direction.
4. The self-adaptive braking mechanism of the horizontal machining center workbench according to claim 3, wherein the phase-change heat storage unit (5) is arranged in a radial ventilation groove of the brake disc (1), the phase-change heat storage unit (5) comprises an aluminum honeycomb framework (51) and solid-liquid phase composite materials (52) filled in holes of the honeycomb framework, the outer wall surface of the aluminum honeycomb framework (51) is in interference fit with the groove wall of the radial ventilation groove, and the temperature sensing unit comprises an annular heat conduction cavity (6) coaxially embedded in the non-friction end surface of the brake disc (1) and a non-contact infrared temperature measurement probe arranged in the annular heat conduction cavity (6).
5. The self-adaptive braking mechanism for a horizontal machining center workbench according to claim 4, wherein the annular heat conducting cavity (6) is thermally connected with the disc body of the brake disc (1) and the aluminum honeycomb skeleton (51) through a plurality of heat conducting fins extending along the radial direction.
6. The adaptive braking mechanism of a horizontal machining center table according to claim 5, wherein a first temperature threshold t_turn and a second temperature threshold t_act are pre-stored in the controller, wherein t_act > t_turn, the controller is configured to execute control logic that controls the centrifugal fan (3) to start operating at a first power P1 when a detection value T of the non-contact infrared temperature probe is equal to or greater than t_turn, controls the centrifugal fan (3) to switch to a higher second power P2 to operate when T is equal to or greater than t_act, and controls the shape memory alloy actuator to drive the adjustable guide vane (42) to rotate to a first expansion angle α1.
7. The adaptive braking mechanism of a horizontal machining center table according to claim 6, wherein the controller is further configured to calculate the rising rate dT/dT of the detected value T in real time, and when the rising rate dT/dT exceeds a preset critical change rate k_max, the controller immediately executes a peak heat dissipation scheme regardless of whether T reaches t_act, controlling the centrifugal fan (3) to operate at a maximum power p_max, and controlling the shape memory alloy actuator to drive the adjustable guide vane (42) to rotate to a maximum expansion angle α_max.
8. The self-adaptive braking mechanism of a horizontal machining center workbench according to claim 7, wherein an output end of the controller is connected with a numerical control system in a signal manner, and when the controller receives a preparation instruction which is sent by the numerical control system and indicates that the workbench is about to be positioned at a high speed or turned over at a large angle, the controller starts the centrifugal fan (3) in advance and operates at power P2 or P_max before braking action actually occurs, and preheats the shape memory alloy actuator to enable the adjustable guide vane (42) to be adjusted to an angle alpha1 or alpha_max.

Description

Self-adaptive braking mechanism for workbench of horizontal machining center Technical Field The application relates to the technical field of horizontal machining centers, in particular to a workbench self-adaptive braking mechanism of a horizontal machining center. Background In the field of horizontal machining centers, accurate and stable braking of a workbench (such as a digital control turntable) is critical to indexing positioning accuracy and machining quality, a traditional braking mechanism generally depends on a dry friction braking principle, and when frequent start-stop, large inertia high-speed braking or continuous indexing operation is performed, a large amount of instantaneous heat is generated by friction pairs due to intense friction, and if the heat cannot be timely dissipated, the temperature of a brake disc is rapidly increased, heat degradation (namely, the friction coefficient is obviously reduced along with the temperature rise), thermal deformation and even thermal cracking of friction materials are possibly caused, so that the stability of braking torque and the positioning accuracy of the workbench are seriously affected. In the prior art, common heat dissipation improvement measures are to add a heat dissipation rib of a brake disc, set a fixed air duct for forced air cooling or set a cooling liquid channel inside the brake disc for liquid cooling. However, the fixed air duct is difficult to dynamically adjust the direction and strength of air flow according to the local overheat area of the brake disc, the cooling efficiency is limited, the liquid cooling system has a complex structure, the risks of sealing failure and liquid leakage pollution to the processing area are existed, and the maintenance cost is high. In addition, most of the existing schemes are passive or simple open-loop cooling, lack of real-time sensing and self-adaptive regulation and control capability of the thermal state in the braking process, cannot provide timely and sufficient cooling when the braking is suddenly carried out under high thermal load, and are difficult to realize energy-saving operation under light load. Disclosure of Invention In order to solve the problems, the application provides a self-adaptive braking mechanism of a workbench of a horizontal machining center. The application provides a self-adaptive braking mechanism for a workbench of a horizontal machining center, which adopts the following technical scheme: a horizontal machining center workstation self-adaptation brake mechanism, includes: A brake assembly comprising a brake disc rotating in synchronism with the table spindle and an opposed caliper applying friction braking to the brake disc; The heat dissipation assembly comprises a centrifugal fan and a variable guide air duct, the variable guide air duct is arranged on an air outlet path of the centrifugal fan, and the variable guide air duct is used for guiding cooling air flow to a friction surface of the brake disc; the heat storage assembly comprises a phase change heat storage unit integrated inside the brake disc; The intelligent control assembly comprises a controller, a rotating speed sensor for detecting the rotating speed of the brake disc and a temperature sensing unit for detecting the equivalent temperature of the phase-change heat storage unit; The controller is respectively connected with the rotating speed sensor, the temperature sensing unit, the centrifugal fan and the driving unit of the variable guide air duct in a signal manner; The controller is configured to perform cooperative closed-loop control of the power of the centrifugal fan and the guide angle of the variable guide duct based on feedback signals of the rotational speed sensor and the temperature sensing unit. As a preferable technical scheme of the application, the variable guide air duct comprises an annular air guide cover and a plurality of adjustable guide vanes arranged in the annular air guide cover, the adjustable guide vanes are uniformly distributed along the circumferential direction of the annular air guide cover and are respectively connected to the annular air guide cover through shape memory alloy actuators, and the shape memory alloy actuators deform under the current control of the controller so as to drive the corresponding adjustable guide vanes to rotate around the rotating shafts of the adjustable guide vanes, so that the air outlet angle and the air flow coverage area of the air duct are changed. As a preferable technical scheme of the application, a circle of vortex generating structure is arranged at the edge of the air outlet of the annular air guide sleeve, and the vortex generating structure is composed of a plurality of micro turbulence fins which form an included angle of 15-60 degrees with the plane of the air outlet and are alternately inclined along the circumferential direction. According to the preferable technical scheme, the phase-change heat storage unit is ar