Anti-falling device and method for servo linkage control band-type brake mechanism
By identifying the backlash of the brake and accurately operate the 1/2 brake backlash stroke in the servo-linked control brake mechanism, the load drop problem during start-up and shutdown of the servo motor is solved, and more stable control effects and more Small action impact.
Patent Information
- Application Number
- CN202411499486.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-10-25
- Publication Date
- 2024-12-27
AI Technical Summary
Under servo linkage control, the load may fall or crash due to the backlash and gravity of the brake during the motor start and shutdown. The existing technology is difficult to effectively solve this problem.
By introducing the brake backlash identification into the servo linkage control brake mechanism, the brake is released with the 1/2 brake backlash stroke when the servo motor is started, and the brake is locked with the 1/2 brake backlash stroke when the machine is stopped. , ensure that the motor is disabled in a static friction state and avoid the load falling.
It effectively reduces load oscillation and fall phenomena, and has extremely short operating time and range, avoids the load collision risk caused by traditional methods, and improves control accuracy and safety.
Smart Images
Figure CN119188853A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of servo drivers, and in particular to an anti-falling device and method for a servo linkage controlled brake mechanism. Background Art
[0002] In industrial control vertical operation occasions or robot arms, where a brake is needed to maintain the end power-off position, a servo motor is generally used in conjunction with a power-off brake to complete this function. The control method of the power-off brake is divided into independent control and servo linkage control. In order to simplify wiring and programming logic, servo linkage control is generally used to enable the brake and servo motor. This control strategy is generally used in the industry with a simple timing control, that is, when it is necessary to run, the motor is enabled first and then the brake is released; when it is necessary to stop, the brake is locked first and then the motor is disabled.
[0003] This control strategy is simple to use and easy to implement, but it often encounters different degrees of uncontrollable load drops or even crashes when the machine needs to be running or stopped. The built-in brake of the servo motor is limited by space and power. Generally, the locking torque is only slightly larger than the rated torque of the motor, and the servo motor generally supports 2-3 times the torque overload, which leads to misleading phenomena: 1. At startup (i.e. the brake release process), after the motor is enabled, the load drops or shakes slightly; 2. At shutdown (i.e. the brake locking process), after the motor is disabled, the load drops slightly or completely crashes.
[0004] After sending the start command (servo ON) when the motor is stopped, the motor controlled by servo linkage will first enable the motor and then release the brake. Due to the objective existence of the brake backlash and gravity, and in general, the position loop is used to perform the axis positioning operation, and the position loop is a closed-loop control system with static error. In the initial state, the motor will not output to balance the load gravity. At this time, the end of the load will slide down a distance and be stabilized by the position loop or produce a certain degree of jitter near the original position. The specific phenomenon depends on the servo position loop bandwidth. If the position loop bandwidth is high, the drop is not obvious. If the position loop bandwidth is not high, there will be obvious drop or jitter or even divergent oscillation out of control. Obviously, a higher position loop bandwidth can alleviate this problem, but since a higher position loop bandwidth generally introduces high-frequency resonance between the servo system and the mechanical structure, a medium to high position loop bandwidth is generally selected for field applications. This leads to the general phenomenon that the load falls slightly for a distance and is pulled back to the original position by the motor. There may be a small convergence oscillation in the process, and the control effect is unsatisfactory.
[0005] For the second case, the specific phenomenon is: after the motor stops and the stop command is sent (servo OFF), the brake controlled by servo linkage will first perform the locking action, and then the servo motor will be disabled. Due to the objective existence of the brake backlash and gravity, the end of the load will slide down a distance, which is much larger than the brake backlash. This sliding distance is actually completed in an out-of-control state. If the brake backlash is too large or the load is too heavy, it may even be completely unable to stop until the machine crashes. Analysis of the cause: The root cause of this phenomenon is that the brake can completely lock the motor shaft under the rated load in a stationary state, but due to the backlash, the load accelerates a short distance under the action of gravity, and the brake's initial working state changes from static friction to sliding friction, and the sliding friction is generally smaller than the maximum static friction. At this time, if the load gravity is less than the sliding friction, the load will gradually decelerate and stop after sliding down a certain distance; if the load gravity is greater than the sliding friction, the load will gradually accelerate, and a collision event will eventually occur at the load end. The severity of the collision is also related to the length of the accelerable stroke. If the stroke is long enough, a vicious high-speed collision will occur, causing serious losses to the equipment. Summary of the invention
[0006] The object of the present invention is to provide a servo linkage controlled brake mechanism anti-falling device and method to solve the problems raised in the above background technology.
[0007] To achieve the above-mentioned purpose, the present invention provides the following technical solutions: an anti-falling device of a servo linkage controlled brake mechanism, comprising a servo driver and a servo motor, a brake device is arranged on the servo motor, an inner sleeve clamping ring is arranged inside the brake device, a plurality of latching teeth are arranged on the inner sleeve clamping ring, a plurality of latching grooves are arranged on the inner wall of the brake device, the latching teeth are embedded in the latching grooves one by one, and a back gap is formed between the latching teeth and the latching grooves.
[0008] A method for preventing falling of a servo linkage controlled brake mechanism comprises the following steps: S1: Brake backlash identification; S2: The servo motor starts and the brake is released; S3: The servo motor stops and the brake is locked.
[0009] Preferably, the specific process of S1 is: start brake backlash identification, the brake performs locking action, the servo driver controls the motor to run in the positive direction with 1 / 2 of the brake rated torque, and records the current motor angle A1 after detecting motor stall, the servo driver controls the motor to run in the reverse direction with 1 / 2 of the brake rated torque, and records the current motor angle A2 after detecting motor stall, the servo driver controls the motor to stop running, calculates the brake backlash Backlash = A1-A2, writes the brake backlash parameters, and completes the brake backlash identification.
[0010] Preferably, the specific process of S2 is: the servo driver receives the "servo ON" command, the servo control motor is enabled, the servo driver controls the motor to run in the upward direction with 1 / 2 brake backlash stroke, after the motor positioning is completed, the servo executes the brake release operation, and after waiting for the brake release to be completed, the servo driver controls the motor to run in the downward direction with 1 / 2 brake backlash stroke to return to the original position, and the brake release is completed.
[0011] Preferably, the specific process of S3 is: the servo driver receives the "servo OFF" command and waits for the motor to stop. If the motor is still running, the servo driver first controls the motor to stop. The servo driver controls the motor to run in the upward direction with 1 / 2 brake backlash stroke. After the motor positioning is completed, the servo executes the brake locking operation, and after the brake locking is completed, the servo driver controls the motor to run in the downward direction with 1 / 2 brake backlash stroke back to the original position. The servo control motor is disabled, and the brake locking is completed.
[0012] Compared with the prior art, the present invention has the following beneficial effects: The present invention proposes a servo linkage control brake mechanism anti-falling device and method. After the servo driver receives a start signal (servo ON), the servo driver first outputs a motor control signal to enable the motor, and then controls the motor to run in the load rising direction by 1 / 2 of the brake backlash. After positioning is completed, the servo driver performs a brake release operation. After the brake is released (both the brake release and locking operation times have corresponding parameter settings), the servo driver controls the motor to run in the load descending direction by 1 / 2 of the brake backlash (i.e., return to the original position). At this point, the brake release operation process is completed, and the servo driver is controlled by the host computer command. Because the brake action time is generally at the level of 10ms and the brake backlash is generally within 1°, the operation takes a very short time and a very small action range, which is much smaller than the impact caused by the traditional direct release of the brake and the resulting load oscillation. Also, after the servo drive receives the stop signal (servo OFF), if the motor is still running, the servo drive first controls the motor to complete the shutdown. After the motor stops steadily, it controls the motor to run in the direction of load rise by 1 / 2 of the brake back clearance. After positioning is completed, the servo drive performs the locking brake operation. After the brake is locked (the brake release and locking operation time have corresponding parameter settings), the servo drive controls the motor to run in the direction of load drop by 1 / 2 of the brake back clearance (that is, return to the original position). At this time, the brake is in a static friction state, so after the motor is disabled, it will no longer fall out of control. BRIEF DESCRIPTION OF THE DRAWINGS
[0013] Figure 1 It is a partial structural schematic diagram of the device of the present invention.
[0014] Figure 2 For the present invention Figure 1 Enlarged view of point A in the middle.
[0015] Figure 3 This is a flow chart of brake backlash identification according to the present invention.
[0016] Figure 4 This is a flow chart of brake release of the present invention.
[0017] Figure 5 This is a flow chart of the brake locking process of the present invention.
[0018] In the figure: brake 1, inner sleeve retaining ring 2, retaining teeth 3, backlash 4. DETAILED DESCRIPTION
[0019] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.
[0020] See also Figures 1 to 5 The present invention provides a technical solution: an anti-falling device of a servo linkage controlled brake mechanism, comprising a servo driver and a servo motor. A brake 1 is arranged on the servo motor. An inner sleeve clamping ring 2 is arranged inside the brake 1. A plurality of latching teeth 3 are arranged on the inner sleeve clamping ring 2. A plurality of latching grooves are arranged on the inner wall of the brake 1. The latching teeth 3 are embedded in the latching grooves one by one, and a back gap 4 is formed between the latching teeth 3 and the latching grooves.
[0021] A method for preventing falling of a servo linkage controlled brake mechanism comprises the following steps: S1: Brake backlash identification; S2: The servo motor starts and the brake is released; S3: The servo motor stops and the brake is locked.
[0022] The specific process of S1 is as follows: start the brake backlash identification, the brake performs the locking action, the servo drive controls the motor to run in the positive direction with 1 / 2 of the brake rated torque, and records the current motor angle A1 after detecting the motor stall, the servo drive controls the motor to run in the reverse direction with 1 / 2 of the brake rated torque, and records the current motor angle A2 after detecting the motor stall, the servo drive controls the motor to stop running, calculates the brake backlash 4Backlash=A1-A2, writes the brake backlash parameters, and completes the brake backlash identification.
[0023] The specific process of S2 is as follows: the servo driver receives the "servo ON" command, the servo control motor is enabled, and the servo driver controls the motor to run in the upward direction with 1 / 2 brake backlash stroke. After the motor positioning is completed, the servo executes the brake release operation. After waiting for the brake release to be completed, the servo driver controls the motor to run in the downward direction with 1 / 2 brake backlash stroke to return to the original position, and the brake release is completed.
[0024] The specific process of S3 is as follows: the servo driver receives the "servo OFF" command and waits for the motor to stop. If the motor is still running, the servo driver first controls the motor to stop. The servo driver controls the motor to run in the upward direction with 1 / 2 brake backlash stroke. After the motor positioning is completed, the servo performs the brake locking operation. After waiting for the brake locking to be completed, the servo driver controls the motor to run in the downward direction with 1 / 2 brake backlash stroke to return to the original position. The servo control motor is disabled and the brake locking is completed.
[0025] The present invention proposes an anti-falling device and method for a servo linkage controlled brake mechanism. After the servo driver receives a start signal (servo ON), the servo driver first outputs a motor control signal to enable the motor, and then controls the motor to run in the load rising direction by 1 / 2 of the brake backlash. After positioning is completed, the servo driver performs a brake release operation. After the brake is released (the brake release and locking operation times are both set with corresponding parameters), the servo driver controls the motor to run in the load descending direction by 1 / 2 of the brake backlash (i.e., return to the original position). At this point, the brake release operation process is completed, and the servo driver is controlled by the host computer command. Because the brake action time is generally at the 10ms level and the brake backlash is generally within 1°, the present invention The operation time is extremely short and the range of action is extremely small, which is much smaller than the impact caused by the traditional direct release of the brake and the resulting load oscillation. In addition, after the servo drive receives the stop signal (servo OFF), if the motor is still running, the servo drive first controls the motor to complete the shutdown. After the motor stops steadily, the motor is controlled to run in the direction of the load rising by 1 / 2 of the brake back clearance. After the positioning is completed, the servo drive performs the locking brake operation. After the brake is locked (the brake release and locking operation time have corresponding parameter settings), the servo drive controls the motor to run in the direction of the load descending by 1 / 2 of the brake back clearance (that is, return to the original position). At this time, the brake is in a static friction state, so after the motor is disabled, it will no longer fall out of control.
[0026] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.
Claims
1. A servo linkage controlled brake mechanism anti-falling device, characterized in that: The invention comprises a servo drive and a servo motor. The servo motor is provided with a brake (1). An inner sleeve clamping ring (2) is provided inside the brake (1). A plurality of latching teeth (3) are provided on the inner sleeve clamping ring (2). A plurality of latching grooves are provided on the inner wall of the brake (1). The latching teeth (3) are embedded in the latching grooves in a one-to-one correspondence. A backlash (4) is formed between the latching teeth (3) and the latching grooves.
2. A method for preventing falling of a servo linkage controlled brake mechanism according to claim 1, characterized in that: The following steps are included: S1: Brake backlash identification; S2: The servo motor starts and the brake is released; S3: The servo motor stops and the brake is locked.
3. The anti-falling method of a servo linkage controlled brake mechanism according to claim 2, characterized in that: The specific process of S1 is as follows: The brake backlash identification starts. The brake performs locking action. The servo drive controls the motor to run in the positive direction at 1 / 2 of the rated brake torque. After detecting the motor stall, the current motor angle A1 is recorded. The servo drive controls the motor to run in the reverse direction at 1 / 2 of the rated brake torque. After detecting the motor stall, the current motor angle A2 is recorded. The servo drive controls the motor to stop running and calculates the brake backlash (4): Backlash = A1-A2. The brake backlash parameters are written. The brake backlash identification is completed.
4. The anti-falling method of a servo linkage controlled brake mechanism according to claim 2, characterized in that: The specific process of S2 is as follows: The servo driver receives the "Servo ON" command, and the servo control motor is enabled. The servo driver controls the motor to run in the upward direction with 1 / 2 brake backlash stroke. After the motor positioning is completed, the servo performs the brake release operation. After waiting for the brake release to be completed, the servo driver controls the motor to run in the downward direction with 1 / 2 brake backlash stroke to return to the original position, and the brake release is completed.
5. The anti-falling method of a servo linkage controlled brake mechanism according to claim 2, characterized in that: The specific process of S3 is as follows: The servo drive receives the "servo OFF" command and waits for the motor to stop. If the motor is still running, the servo drive first controls the motor to stop. The servo drive controls the motor to run in the upward direction with 1 / 2 brake backlash stroke. After the motor positioning is completed, the servo performs the brake locking operation. After the brake locking is completed, the servo drive controls the motor to run in the downward direction with 1 / 2 brake backlash stroke back to the original position. The servo control motor is disabled and the brake locking is completed.