A control device for a vehicle luggage carrier rolling device

Abstract

The application provides a control device of a car luggage rack rolling equipment, which determines a rolling starting point and a rolling ending point of a rolling execution end rolling on the luggage rack according to the extension distance of a cylinder rod. In the luggage rack rolling stage between the rolling starting point and the rolling ending point, the controller controls the electromagnetic proportional valve based on the feedback of the pressure sensor by using a PID algorithm, and then controls the rolling force. The control device can correctly determine the cylinder force position and has no influence on the vehicle body. Meanwhile, the parameter adjustment is convenient, the whole output pressure can be controlled through four parameters (a proportional coefficient P, a differential time D, a maximum air pressure output PM and an initial air pressure setting IP), and the maintenance and adjustment are convenient.

Description

Technical Field

[0001] This invention relates to the field of automobile roof rack rolling technology, and more specifically to a control device for automobile roof rack rolling equipment. Background Technology

[0002] A roof rack is a type of body trim on a vehicle. The roof rack has rubber strips and buckles. The buckles can be installed manually, but the rubber strips need to be rolled to fully bond the roof rack to the vehicle body.

[0003] Currently, there are several issues with the rolling process of car roof racks, which affect vehicle quality and cost.

[0004] Question 1: Reference Figure 1 The current rolling pressure control of rolling equipment is unstable, with many pressure failures, resulting in a large amount of rework. There is no basis for modifying the pressure control parameters, and they are set based solely on experience.

[0005] Question 2: Current rolling equipment uses photoelectric sensors to detect the car body and control the rolling action accordingly. Photoelectric sensors are more accurate in detecting light-colored car bodies, but for black car bodies, due to the high absorption of the spectrum by black, the error is large. This can lead to situations where the rolling is not performed or the cylinder suddenly drops after a misjudgment, resulting in the hood being scrapped. Even if a judgment sensor is added, most sensors have blind spots for black car bodies, and the correct signal cannot be guaranteed.

[0006] Question 3: The current rolling equipment does not accurately determine the starting and ending points of rolling, resulting in some pressure being applied to the body sheet metal, causing quality problems such as sheet metal deformation.

[0007] In view of the above problems, the inventors of this invention have finally obtained this invention after a long period of research and practice. Summary of the Invention

[0008] To solve the above-mentioned technical problems, the present invention provides a control device for automobile roof rack rolling equipment to ensure rolling quality.

[0009] The technical solution adopted in this invention is as follows:

[0010] A control device for a car roof rack rolling device is provided, the rolling device including a rolling cylinder and a rolling actuator connected to the end of the cylinder rod of the rolling cylinder;

[0011] The control device includes:

[0012] The sensor reflector is fixed to the cylinder rod or the rolling actuator end;

[0013] A photoelectric sensor, fixed on the rolling cylinder, measures the extension distance of the cylinder rod based on feedback from the sensor reflector.

[0014] An electromagnetic proportional valve is installed in the air circuit of the rolling cylinder to control the pressure output of the rolling cylinder.

[0015] A pressure sensor is installed on the rolling actuator end to detect the real-time rolling pressure.

[0016] The controller is electrically or communicatively connected to the photoelectric sensor, the electromagnetic proportional valve, and the pressure sensor, respectively. The controller determines the starting and ending points of the rolling action on the luggage rack based on the extension distance of the cylinder rod. During the luggage rack rolling stage between the starting and ending points, the controller uses a PID algorithm based on the feedback from the pressure sensor to control the electromagnetic proportional valve, thereby controlling the rolling force.

[0017] In some embodiments, after the rolling cylinder descends, the controller controls the electromagnetic proportional valve to be in the initial output state, so that the rolling actuator outputs the initial rolling force. Under this initial rolling force, the rolling actuator does not produce dents on the body sheet metal when it acts on the body sheet metal. When the rolling start point is reached, the controller uses a PID algorithm to control the electromagnetic proportional valve.

[0018] In some embodiments, the rolling cylinder rises when the rolling execution end reaches the rolling end point.

[0019] In some embodiments, during the luggage rack rolling stage, the controller uses the proportional-derivative control law in the PID algorithm to control the electromagnetic proportional valve.

[0020] In some embodiments, the control device further includes a vehicle body detection sensor, which is communicatively connected to the controller; the vehicle body detection sensor is used to detect whether the vehicle body has reached the rolling station, and after the vehicle body reaches the rolling station, the controller controls the rolling cylinder to fall.

[0021] In some embodiments, the vehicle body detection sensor is a proximity switch mounted on the bottom surface.

[0022] In some embodiments, after the vehicle body reaches the rolling station, the rolling cylinder descends, and the rolling execution end contacts the vehicle body sheet metal and travels from above the A-pillar of the vehicle body, and then reaches the rolling starting point.

[0023] In some embodiments, after the rolling cylinder descends, when the cylinder rod extension distance measured by the photoelectric sensor is equal to the rolling start setting value, the controller determines that the rolling start point has been reached; when the cylinder rod extension distance measured by the photoelectric sensor is equal to the rolling end setting value, the controller determines that the rolling end point has been reached, and simultaneously controls the rolling cylinder to rise.

[0024] In some embodiments, the controller controls the maximum output of the electromagnetic proportional valve to avoid overpressure.

[0025] In some embodiments, the controller is also connected to an alarm device and controls the alarm device to issue an alert in the following situations:

[0026] The rolling pressure fed back by the pressure sensor is not within the acceptable range of the process requirements;

[0027] The rolling process was abnormally interrupted;

[0028] The rolling action was not performed when the vehicle body was in place.

[0029] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0030] This invention uses distance as a calculation method to accurately determine the start and end of the rolling process, ensuring stable pressure from the rolling rollers on the vehicle's roof rack. Pressure control stability is high, with an accuracy of ±10N error. It eliminates stress on the vehicle's sheet metal, effectively guaranteeing the normal output of rolling pressure and reducing the problem of numerous unqualified rolling processes. Attached Figure Description

[0031] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0032] Figure 1 The diagram shows the rolling pressure curve of an existing car roof rack rolling device under working conditions.

[0033] Figure 2 A schematic diagram showing the arrangement of photoelectric sensors and reflectors in an embodiment of the automobile roof rack rolling device of the present invention is provided.

[0034] Figure 3 The diagram shows the rolling pressure curve of the car roof rack rolling equipment under working conditions when the cylinder rod extension distance is used to determine the rolling start point and rolling end point, but the control algorithm is not improved.

[0035] Figure 4 The diagram shows the rolling pressure curve of the car roof rack rolling equipment under working conditions, after using the extension distance of the cylinder rod to determine the starting and ending points of rolling and combining it with PID algorithm control. Detailed Implementation

[0036] The above-mentioned and other technical features and advantages of the present invention will be described in more detail below with reference to the accompanying drawings.

[0037] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between them; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0038] like Figure 2 The described car roof rack rolling device includes a rolling cylinder 1 and a rolling actuator 2 connected to the end of the cylinder rod 11 of the rolling cylinder 1. An electromagnetic proportional valve (not shown in the figure) on the air circuit of the rolling cylinder 1 is used to control the pressure output of the rolling cylinder 1. A pressure sensor (not shown in the figure) is installed on the rolling actuator 2 to detect the real-time rolling pressure.

[0039] The controller of this invention determines the starting and ending points of the rolling action 2 onto the luggage rack 100 based on the extension distance of the cylinder rod 11. The extension distance of the cylinder rod 11 is detected using a photoelectric sensor 3 and a sensor reflector 4. The photoelectric sensor 3 is fixed to the rolling cylinder 1, and the sensor reflector 4 is fixed to either the cylinder rod 11 or the rolling action 2. The photoelectric sensor 3 and sensor reflector 4 are a separate module, powered by 24V DC from the electrical cabinet, eliminating the need for battery replacement; they can be easily installed on existing equipment with screws using only simple drilling, requiring no adjustments to the existing equipment. The photoelectric sensor 3 measures the extension distance of the cylinder rod 11 based on feedback from the sensor reflector 4.

[0040] The photoelectric sensor 3 has a built-in analog output, which is connected to the analog input terminal of the controller. The positions of the photoelectric sensor 3 and the sensor reflector 4 are pre-adjusted to ensure accurate input values. During operation, after the ground-detecting metal proximity switch detects the vehicle body, the control device controls the rolling cylinder to drop. The sensor detects the extension distance to determine whether the rolling has reached the luggage rack 100 (reaching the rolling start point). Before rolling onto the luggage rack 100, the output proportional valve is in a weak output state to ensure that the body sheet metal is free of dents. During the luggage rack rolling stage from the rolling start point to the rolling end point, if the pressure control method of the existing equipment is used, the pressure curve is as follows: Figure 3 As shown, from Figure 3 As can be seen above, the pressure curve still fluctuates.

[0041] It should be noted that if the air pressure is 0 at the moment the rolling cylinder reaches the starting point of the rolling process (100° on the luggage rack), and there is a lag in the air pressure control, then the rolling pressure of the first small section of the luggage rack will definitely be unqualified. Therefore, after the rolling cylinder descends, the electromagnetic proportional valve is in the initial output state, so that the rolling actuator outputs the initial rolling pressure, thereby improving the rolling pass rate of the luggage rack.

[0042] Furthermore, the controller includes a PLC. During the luggage rack rolling stage, the PLC implements PID algorithm control to control the electromagnetic proportional valve, thereby controlling the rolling pressure. In a specific example, the PID module (FB41 continuous control module) built into the Siemens PLC is used as the basic control scheme to implement the classic PID algorithm. Considering the special characteristics of air pressure control, a PD control scheme is adopted, thus controlling the system's control hysteresis.

[0043] For example, the PID algorithm utilizes a Siemens built-in function block, where the parameters are set to PD proportional-derivative control.

[0044] Before rolling onto the luggage rack 100, the output pressure is as follows: In the debugging state, adjust the proportional valve output V(B) to obtain the actual value P = 110N from the pressure sensor, and obtain the initial air pressure value IP. At this time, IP = V(B). This value is the optimal initial value of the pressure curve before PD control intervention. The actual output output = V(B) = IP.

[0045] After rolling onto the luggage rack, the pressure output V(B) = PD (PID control output). Considering the output protection algorithm and overpressure protection algorithm, the intermediate value Vmiddle = V(B) / 100 is converted into an output percentage, and then the intermediate value Vmiddle is multiplied by the maximum pressure output PM. The final result is: actual output output = V(B) / 100 * Pout.

[0046] Before PD control, output = V(B); during PD control, output = V(B) / 100*Pout.

[0047] Since the proportional valve ultimately needs to accept integer parameter values, the output should be calculated using the formula OUT = ((IN – LO_LIM) / (HI_LIM – LO_LIM)) * 27648, where IN is the actual output value, LO_LIM is the minimum output value of the proportional valve, and HI_LIM is the maximum output value. Finally, the OUT value is transmitted to the proportional valve controller to achieve pressure control.

[0048] refer to Figure 4 During the luggage rack rolling stage, the rolling pressure is further controlled by a PID algorithm, and its rolling pressure curve is as follows: Figure 4As shown, this achieves a perfect match between the theoretical rolling pressure and the process rolling pressure.

[0049] When the rolling execution end reaches the rolling end point, the controller controls the rolling cylinder 1 to rise, so that it will not continue to roll to the back cover.

[0050] Preferably, after adding a series of algorithms such as initial air pressure algorithm, output protection algorithm, and overpressure protection algorithm through the PLC, the output is sent to the out terminal to control the proportional valve. The proportional valve can output a maximum air pressure of 6 bar, but the maximum detection range of the pressure sensor is only 300 N. If the parameter setting is incorrect, it will inevitably have an adverse effect on the vehicle body and sensors, so it is necessary to control the maximum output.

[0051] The rolling process is as follows: Before use, switch the equipment operation panel to automatic mode and wait for the rolling signal to be triggered. During rolling, the rollers rise under upward force, and the distance change detected by the photoelectric sensor is sent to the programmable logic controller (PLC). Since the roof rack is an irregular curved surface, the start or end of rolling can be determined when the set value for starting rolling equals the measured value. The PID calculation function continuously works during rolling to ensure normal rolling pressure. At the end of rolling, if the set value for ending rolling equals the measured value, it is determined to be finished, and the cylinder rises, preventing further rolling to the rear cover.

[0052] If the rolling process fails to meet the following conditions: 1. The rolling pressure is outside the acceptable range of the process requirements; 2. The rolling process is abnormally interrupted: for example, due to air pressure failure, manual intervention, or the mechanical protection device of the equipment being triggered during rolling; 3. The rolling machine is not performing rolling, meaning the rolling signal is met but the equipment is not activated. In this case, the buzzer will sound an alarm, and the red indicator light will flash, indicating that a failure has occurred.

[0053] This invention uses distance as a calculation method to accurately determine the start and end of rolling, correctly identifying the cylinder's force application position without affecting the vehicle body. The algorithm for the proportional valve output has been verified on over 18,000 vehicles, and no pressure control anomalies have been observed. Furthermore, parameter adjustment is convenient; the entire output pressure can be controlled using only four parameters (proportional coefficient P, derivative time D, maximum air pressure output PM, and initial air pressure setting IP), facilitating maintenance and adjustment.

[0054] The above are merely preferred embodiments of the present invention and are illustrative rather than restrictive. The structure and connection methods of the components in the present invention can be varied, and any equivalent transformations and improvements made based on the technical solution of the present invention should not be excluded from the protection scope of the present invention.

Claims

1. A control device for a car roof rack rolling device, the rolling device comprising a rolling cylinder and a rolling actuator connected to the end of the cylinder rod of the rolling cylinder, characterized in that, The control device includes: The sensor reflector is fixed to the cylinder rod or the rolling actuator end; A photoelectric sensor, fixed on the rolling cylinder, measures the extension distance of the cylinder rod based on feedback from the sensor reflector. An electromagnetic proportional valve is installed in the air circuit of the rolling cylinder to control the pressure output of the rolling cylinder. A pressure sensor is installed on the rolling actuator end to detect the real-time rolling pressure. The controller is electrically or communicatively connected to the photoelectric sensor, the electromagnetic proportional valve, and the pressure sensor, respectively. The controller determines the starting and ending points of the rolling action on the luggage rack based on the extension distance of the cylinder rod. During the luggage rack rolling stage between the starting and ending points, the controller uses a PID algorithm based on the feedback from the pressure sensor to control the electromagnetic proportional valve, thereby controlling the rolling force.

2. The control device for a car roof rack rolling equipment as described in claim 1, characterized in that, After the rolling cylinder descends, the controller controls the electromagnetic proportional valve to be in the initial output state, so that the rolling actuator outputs the initial rolling force. Under this initial rolling force, the rolling actuator does not produce dents on the body sheet metal when it acts on the body sheet metal. When the rolling start point is reached, the controller uses a PID algorithm to control the electromagnetic proportional valve.

3. The control device for a car roof rack rolling equipment as described in claim 1, characterized in that, When the rolling execution end reaches the rolling end point, the rolling cylinder rises.

4. The control device for a car roof rack rolling equipment as described in claim 1 or 2, characterized in that, During the luggage rack rolling stage, the controller uses the proportional-derivative control law in the PID algorithm to control the electromagnetic proportional valve.

5. The control device for a car roof rack rolling equipment as described in claim 2, characterized in that, It also includes a vehicle body detection sensor, which is communicatively connected to the controller; the vehicle body detection sensor is used to detect whether the vehicle body has reached the rolling station, and after the vehicle body reaches the rolling station, the controller controls the rolling cylinder to fall.

6. The control device for a car roof rack rolling equipment as described in claim 5, characterized in that, The vehicle body detection sensor is a proximity switch mounted on the bottom surface.

7. The control device for a car roof rack rolling equipment as described in claim 5, characterized in that, After the car body reaches the rolling station, the rolling cylinder descends, and the rolling actuator contacts the car body sheet metal, travels from above the A-pillar of the car body, and then reaches the rolling starting point.

8. The control device for a car roof rack rolling equipment as described in claim 2, characterized in that, After the rolling cylinder descends, when the cylinder rod extension distance measured by the photoelectric sensor is equal to the rolling start setting value, the controller determines that the rolling start point has been reached; when the cylinder rod extension distance measured by the photoelectric sensor is equal to the rolling end setting value, the controller determines that the rolling end point has been reached, and simultaneously controls the rolling cylinder to rise.

9. The control device for a car roof rack rolling equipment as described in claim 1, characterized in that, The controller controls the maximum output of the electromagnetic proportional valve to avoid overpressure.

10. The control device for a car roof rack rolling equipment as described in claim 9, characterized in that, The controller is also connected to the warning device and controls the warning device to issue an early warning under the following conditions: The rolling pressure fed back by the pressure sensor is not within the acceptable range of the process requirements; The rolling process was abnormally interrupted; The rolling action was not performed when the vehicle body was in place.

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