A method and device for measuring the force constant of a bond head

Abstract

The present invention provides a method and device for measuring the force constant of a ram, wherein the measuring method comprises: controlling a lifting motor to move a high-precision pressure sensor to a plurality of positions to be measured selected within the entire stroke to be measured, and recording the position P(k) of the ram mechanism; inputting a current I(t) to press the porcelain nozzle against the high-precision pressure sensor until the pressure value changes, and recording the input current I(t) and the reading F(t) of the high-precision pressure sensor; calculating the force constant Kf(k) at position P(k), and after obtaining the force constant Kf(k) data set at different positions, linearly fitting the force constant Kf(k) data set. The method and device for measuring the force constant of a ram provided by the present invention can accurately measure the characteristic value of the force constant of the ram in the range of the motion stroke, thereby accurately judging whether the force constant of the ram meets the design and use requirements, and can be applied to the mass production quality control, performance evaluation and optimization of the ram mechanism.

Description

Technical Field

[0001] The invention relates to the technical field of welding equipment, and in particular to a method and a device for measuring a welding head force constant. Background Art

[0002] In the production and assembly of Bangtou motors, due to the differences in incoming materials and assembly errors of electronic circuits, Bangtou movers and stators, there will be deviations between the actual force constant of the Bangtou and the designed force constant, making it impossible to accurately evaluate whether the force constant of the Bangtou meets the usage requirements.

[0003] To solve the above problems, the traditional method is to place the measuring device in a fixed position and measure the force constant at the fixed position. However, the above method cannot obtain information about the change of the force constant with respect to the position. In addition, the industry also estimates the relationship between the force constant and the position of the bonding head by giving a mathematical model of voltage, current and position; however, due to the deviation between the theoretical model and the actual system, this method has certain errors in industrial applications and cannot meet the high-precision measurement requirements of welding equipment. Summary of the invention

[0004] The invention provides a method and a device for measuring the force constant of a binding head, which can accurately measure the force constant of the binding head mechanism, thereby accurately evaluating whether the force constant of the binding head mechanism meets the use requirements.

[0005] The technical solution adopted by the present invention is: a device for measuring the force constant of a ram, which comprises: a main control system, a measuring mechanism, a driver and a ram mechanism; the driver is connected to the main control system for communication, the measuring mechanism comprises a fixing fixture, a high-precision pressure sensor and a lifting motor; the high-precision pressure sensor is installed on the fixing fixture, the lifting motor is mechanically connected to the fixing fixture, and the high-precision pressure sensor and the lifting motor are both connected to the main control system for communication;

[0006] The bungee mechanism includes a bungee body, a voice coil motor mechanically connected to the bungee body, and a position detection component; the voice coil motor is connected to a driver; the position detection component is installed on the bungee body and is communicatively connected to a main control system to detect the position information of the bungee body; a porcelain nozzle is provided at the end of the bungee body, and a high-precision pressure sensor is used to measure the pressure of the porcelain nozzle, and the pressure is transmitted to the main control system through signal conversion.

[0007] Furthermore, the fixing fixture is provided with an execution end, and the high-precision pressure sensor is installed on the execution end of the fixing fixture.

[0008] Furthermore, the voice coil motor includes two stators and a mover sandwiched between the two stators, and the mover is mechanically connected to the main body of the bang head.

[0009] The present invention also provides the following technical solution: a method for measuring a force constant of a bond head, using the bond head force constant measuring device, comprising the following steps:

[0010] A plurality of positions to be tested are set within the motion stroke to be tested; the lifting motor is controlled to move the high-precision pressure sensor to each position to be tested in turn; the feedback position P(k) of the binding head mechanism at each position to be tested is recorded, where k is the serial number of the position to be tested;

[0011] Select multiple time points, input different currents I(t) into the voice coil motor at each time point, so that the porcelain mouth is pressed on the high-precision pressure sensor, and the pressure value of the high-precision pressure sensor changes accordingly, and the pressure value F(t) is measured, where t is the time point sequence number;

[0012] According to F(t) = Kf×I(t), the force constant Kf(k) of each position to be measured is calculated;

[0013] The force constant Kf(k) of the bang head mechanism at different positions P(k) is collected to obtain the force constant Kf(k) data set, and the force constant Kf(k) data set is linearly fitted according to the following formula:

[0014] Get the characteristic parameter C of the Bangtou force constant with respect to position i , where 1≤N≤5.

[0015] Compared with the prior art, the method and device for measuring the force constant of the bungee head of the present invention use a lifting motor to drive a high-precision pressure sensor to move to different positions, perform pressure tests on the bungee head mechanisms at different positions, record the corresponding current output, and obtain the corresponding force constant Kf(k). The force constant Kf(k) data sets of the bungee head mechanisms at different positions are then linearly fitted to obtain the characteristic parameters of the bungee head force constant with respect to position, thereby accurately judging whether the bungee head force constant meets the design and use requirements, and can be used for production quality control, performance evaluation and optimization of the bungee head mechanism. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the following specific embodiments, they are used to explain the present invention, but should not constitute a limitation of the present invention.

[0017] Figure 1 : A schematic structural diagram of a device for measuring a force constant of a bond head according to the present invention;

[0018] Figure 2 A schematic block diagram of a device for measuring a force constant of a bond head according to the present invention; DETAILED DESCRIPTION

[0019] The specific implementation of the present invention is described in detail below in conjunction with the accompanying drawings. It should be understood that the specific implementation described here is only used to illustrate and explain the present invention, and is not used to limit the present invention.

[0020] like Figure 1 and Figure 2 As shown, the device for measuring the force constant of the head of the present invention includes a main control system, a measuring mechanism, a driver and a head mechanism; wherein the measuring mechanism, the driver and the head mechanism are all connected to the main control system for communication, the driver is connected to the head mechanism, the main control system controls the driver to drive the head mechanism to move, the measuring mechanism detects the force constant of the head mechanism, and feeds back the data to the main control system.

[0021] Specifically, the measuring mechanism includes a fixed fixture 1, a high-precision pressure sensor 2, and a lifting motor; wherein the fixed fixture 1 is provided with an execution end 101, the high-precision pressure sensor 2 is installed on the execution end 101 of the fixed fixture 1, the lifting motor is mechanically connected to the fixed fixture 1, and the lifting motor is communicatively connected to the main control system. The lifting motor is controlled by the main control system to drive the execution end 101 of the fixed fixture 1 to move up and down, thereby changing the height position of the high-precision pressure sensor 2 to measure the pressure output of the head mechanism at different positions.

[0022] The bang head mechanism includes a bang head body 3, a voice coil motor 4 mechanically connected to the bang head body 3, and a position detection component; wherein the voice coil motor 4 is connected to a driver, and the driver controls the current output to the voice coil motor 4 to drive the bang head body 3 to swing up and down. The position detection component is installed on the bang head body 3 and is connected to the main control system for communication, so as to detect the position information of the bang head body 3. Further, the voice coil motor 4 includes two stators 401 and a mover 402 sandwiched between the two stators 401, wherein the mover 402 is mechanically connected to the bang head body 3. A porcelain nozzle 5 is provided at the end of the bang head body 3, and a high-precision pressure sensor 2 is used to measure the pressure of the porcelain nozzle 5, and the pressure is transmitted to the main control system through signal conversion.

[0023] The working process of the Bangtou force constant measuring device of the present invention is as follows:

[0024] The main control system is provided with an operation control card. The main control system sends a current command to the operation control card, and the operation control card sends the current command to the driver. The current command is processed by the driver and acts on the mover 402. The current passes through the mover 402, and generates a Lorentz force in the magnetic field of the stator 401 to drive the main body 3 of the ram to swing up and down. At the same time, the feedback position of the main body 3 of the ram is transmitted to the operation control card through the position detection component.

[0025] The present invention also provides a method for measuring a force constant of a bond head, comprising the following steps:

[0026] A plurality of positions to be tested are set within the movement stroke to be tested; the lifting motor is controlled to move the high-precision pressure sensor (2) to each position to be tested in sequence, and the feedback position P(k) of the binding head mechanism at each position to be tested is recorded; wherein k is the serial number of the position to be tested;

[0027] Select multiple time points, and input different currents I(t) into the voice coil motor (4) at each time point, so that the porcelain mouthpiece (5) is pressed on the high-precision pressure sensor (2), and the pressure value of the high-precision pressure sensor (2) changes accordingly, and the pressure value F(t) is measured; wherein t is the time point sequence number;

[0028] According to the physical meaning of the motor force constant: F(t) = Kf×I(t), the force constant Kf(k) of each position to be measured is calculated.

[0029] The force constant Kf(k) of the bang head mechanism at different positions P(k) is collected to obtain the force constant Kf(k) data set, and the force constant Kf(k) data set is linearly fitted according to the following formula:

[0030] Get the characteristic parameter C of the Bangtou force constant with respect to position i , where N ≥ 1. In practical applications, due to the consideration of computational complexity, N ≤ 5.

[0031] In summary, the method and device for measuring the force constant of the ram head of the present invention drives the high-precision pressure sensor 2 to move to different positions through a lifting motor, performs pressure tests on the ram head mechanism at different positions, records the corresponding current output, obtains the corresponding force constant Kf(k), and then linearly fits the force constant Kf(k) data set of the ram head mechanism at different positions to obtain the characteristic parameter C of the ram head force constant with respect to the position. i , so as to accurately judge whether the force constant of the bunging head meets the use requirements, and can be used for production quality control, performance evaluation and optimization of the bunging head mechanism.

[0032] As long as it does not violate the creative ideas of the present invention, any combination of the various embodiments of the present invention shall be regarded as the contents disclosed by the present invention; within the technical concept of the present invention, any combination of various simple modifications of the technical scheme and different embodiments that does not violate the creative ideas of the present invention shall be within the protection scope of the present invention.

Claims

1. A method for measuring a force constant of a bond head, using a bond head force constant measuring device for detection, characterized in that: The bonding head force constant measuring device comprises a main control system, a measuring mechanism, a driver and a bonding head mechanism; the driver is communicatively connected to the main control system, and the measuring mechanism comprises a fixing fixture (1), a high-precision pressure sensor (2) and a lifting motor; the high-precision pressure sensor (2) is installed on the fixing fixture (1), the lifting motor is mechanically connected to the fixing fixture (1), and the high-precision pressure sensor (2) and the lifting motor are both communicatively connected to the main control system; The bonding head mechanism comprises a bonding head body (3), a voice coil motor (4) mechanically connected to the bonding head body (3), and a position detection component; the voice coil motor (4) is connected to a driver; the position detection component is installed on the bonding head body (3) and is communicatively connected to a main control system to detect position information of the bonding head body (3); a porcelain nozzle (5) is provided at the end of the bonding head body (3), and a high-precision pressure sensor (2) is used to measure the pressure of the porcelain nozzle (5), and the pressure is transmitted to the main control system through signal conversion; The following steps are involved: A plurality of positions to be tested are set within the movement stroke to be tested; the lifting motor is controlled to move the high-precision pressure sensor (2) to each position to be tested in sequence; and the feedback position P(k) of the binding head mechanism at each position to be tested is recorded, wherein k is the serial number of the position to be tested; Select multiple time points, and input different currents I(t) into the voice coil motor (4) at each time point, so that the porcelain mouthpiece (5) is pressed on the high-precision pressure sensor (2), and the pressure value of the high-precision pressure sensor (2) changes accordingly, and the pressure value F(t) is measured, where t is the time point sequence number; According to F(t) = Kf×I(t), the force constant Kf(k) of each position to be measured is calculated; The force constant Kf(k) of the bang head mechanism at different positions P(k) is collected to obtain the force constant Kf(k) data set, and the force constant Kf(k) data set is linearly fitted according to the following formula: Get the characteristic parameter C of the Bangtou force constant with respect to position i , where 1≤N≤5.

2. The method for measuring the force constant of a bond as claimed in claim 1, characterized in that: The fixing fixture (1) is provided with an execution end (101), and the high-precision pressure sensor (2) is mounted on the execution end (101) of the fixing fixture (1).

3. The method for measuring the force constant of a bond as claimed in claim 1, characterized in that: The voice coil motor (4) comprises two stators (401) and a mover (402) sandwiched between the two stators (401); the mover (402) is mechanically connected to the bonnet body (3).

Images