TWI714367B - Torque detection method of electric hydraulic pulse tool - Google Patents

Abstract

The present invention discloses a torque detection method for an electric oil pulse tool; wherein the electric oil pulse tool includes a power supply unit, a drive unit electrically connected to the power supply unit, and an oil pulse type torque connected to the drive unit in series The generating unit and a detection circuit electrically connected with the power supply unit and the driving unit. With the above structure, the detection circuit is used to determine and control the operation of the drive unit according to the rotation speed and angle of the drive unit, so as to achieve the torque detection function of the electric hydraulic pulse tool.

Description

Torque detection method of electric hydraulic pulse tool

The present invention relates to the technical field related to electric hand-held tools, in particular to a torque detection method for electric hydraulic pulse tools.

Press, the field of pneumatic or electric tools that can produce impact can be roughly divided into two types: direct impact and oil pressure pulse type; among them, oil pressure pulse type tools have longer life, low noise, and low vibration. Characteristics, widely loved by the industry.

In order to be able to control the output torque of the hydraulic pulse type tool, the prior art will design a stop structure inside the tool based on the built-in pressure. However, this type of stop mechanism uses the pressure of the working oil as the driving source, and the pressure of the working oil is It is easily affected by the locking operation or the increase of oil temperature, causing the pressure to sometimes exceed the predetermined value prematurely, or it cannot be in a stable state during the operation, so there will be a misjudgment of stopping before the rotation torque is reached, which may cause When the lock is too tight or too loose.

Furthermore, the production process of the component parts of the stop mechanism of the prior art is sophisticated and complicated, resulting in excessive production costs and maintenance costs, and the incidence of misjudgment is not low, and the stability is not good.

In view of the above-mentioned problems and deficiencies of the prior art, the main purpose of the present invention is to provide a torque detection method for electric hydraulic pulse tools. Solve the lack of prior technology through innovative structural design.

According to the above objective of the present invention, a torque detection method for an electric oil pressure pulse tool is proposed; wherein the electric oil pressure pulse tool includes a power supply unit, a drive unit electrically connected to the power supply unit, and a hydraulic pressure series connected to the drive unit A pulse-type torque generating unit and a detection circuit electrically connected to the power supply unit and the drive unit. With the above structure, the detection circuit is used to determine and control the operation of the drive unit according to the rotation speed and angle of the drive unit, so as to achieve the torque detection function of the electric hydraulic pulse tool.

B‧‧‧Shell

10‧‧‧Power Supply Unit

20‧‧‧Drive unit

30‧‧‧Hydraulic pulse torque generating unit

31‧‧‧Cylinder

32‧‧‧Hydraulic oil

33‧‧‧Leaf

35‧‧‧Strike axis

40‧‧‧Detection circuit

42‧‧‧Angle sensor

44‧‧‧Control Unit

46‧‧‧Control Panel

Figure 1 is a schematic diagram of an embodiment of the electric oil pulse tool of the present invention.

Figure 2 is a cross-sectional schematic diagram of a hydraulic pulse torque generating unit.

Figure 3 is a block diagram of an embodiment of the present invention.

Hereinafter, please refer to the related drawings to further describe the embodiment of the torque detection method of the electric oil pulse tool of the present invention. In order to facilitate the understanding of the embodiment of the present invention, the same components are described below with the same symbols.

Please refer to Figures 1 to 3, the electric oil pressure pulse tool of the present invention includes a housing B, a power supply unit 10 arranged in a preset position of the housing B, a drive unit 20, and a hydraulic pulse type The torque generating unit 30 and a detection circuit 40.

The above-mentioned power supply unit 10 (previous technology) can be a lithium battery or other alternative batteries, and can also be a transformer and a power cord directly connected to the mains.

The aforementioned driving unit 20 (prior art) is electrically connected to the power supply unit 20, and can be a DC brushless motor or other equivalent electric drive motors. In implementation, the shaft (not shown in the figure) output by the drive unit 20 can be further connected in series with a reducer (not shown in the figure).

The above-mentioned hydraulic pulse-type torque generating unit 30 (prior art) is connected to the drive unit 20. The drive unit 20 drives the oil cylinder 31 of the hydraulic pulse-type torque generating unit 30 to rotate. The cylinder 31 is filled with hydraulic oil 32. The blade 33 inside 31 generates a pressure difference and a quantitative pulse to generate torque, and finally the striking shaft 35 outputs torque and repeated shocks. The impact can be generated once as the oil cylinder 31 rotates once, and when the impact is generated, the drive unit 20 is simultaneously subjected to the load, resulting in fast and slow speed changes.

The detection circuit 40 is electrically connected to the driving unit 20 and the power supply unit 10, and includes an angle sensor 42, a control unit 44, and a control panel 46.

The angle sensor 42 is used to detect the rotation state of the shaft of the driving unit 20 and return a sensor signal. In implementation, the content of the sensor signal generally refers to (including but not limited to) the angle, rotation speed, etc. of the rotating shaft of the driving unit 20.

The control panel 46 is arranged on the outer surface of the casing B to provide an interface for the user to make settings, and is triggered by the user to output a setting signal. In implementation, control panel, display plus button set, touch panel or other components with the same function.

The control unit 44 is electrically connected to the angle sensor 42 and the control panel 46 respectively, and controls the operation of the driving unit 20 according to the sensing signal and the setting signal.

Therefore, the foregoing is an introduction to the components and assembly methods of a preferred embodiment of the electric oil pulse tool provided by the present invention. The operating characteristics of the example are introduced as follows.

The control unit 44 of the present invention can be a microprocessor. The control unit 44 is pre-set or set by the control panel 46 to control the operation program of the driving unit 20 and receives the sensor signal from the angle sensor 42. The control unit 44 can calculate the torque and control whether the drive unit 20 runs or not according to the change of the sensing signal. The detection method and calculation are as follows:

<Pulse frequency detection>

According to the driving unit 20 from starting to idling, the rotation speed of the driving unit 20 will always increase, and when the maximum rotation speed is reached, its speed will be the maximum and remain unchanged. The oil cylinder 31 connected to the hydraulic pulse-type torque generating unit 30 is driven to rotate synchronously and actuates the striking shaft 35 in conjunction.

When the striking shaft 35 is running, the driven lock (not shown in the figure, it can be a screw, a nut...) starts to lock and generates resistance, because the oil cylinder 31 of the hydraulic pulse torque generating unit 30 and the internal If the blades 33 are not synchronized, a pulse will be generated (one pause), and the rotation speed of the drive unit 20 will also change (slow down) due to the reaction force. After the oil cylinder 31 passes the pulse position, the rotation speed of the driving unit 20 will increase when the reaction force decreases.

In this way, when the speed of the driving unit 20 slows down once (that is, one pulse), the angle sensor 42 senses the rotation speed and angle changes of the driving unit 20, forming a sensor signal and transmitting it to the control unit 44, so that the control unit 44 can record each pulse The time point, number of times, the speed of the drive unit 20, the position of the cylinder 31, etc., are used to calculate the number of pulses.

<Detect the angle of the striking shaft 35>

According to the driving unit 20 to drive the hydraulic pulse torque generating unit 30 to rotate the striking shaft 35, it is a gear ratio conversion. The angle of rotation of the striking shaft 35 can be obtained by calculating the rotation angle of the output shaft of the driving unit 20. The same applies to the serial connection between the driving unit 20 and the hydraulic pulse-type torque generating unit 30 through a reducer (not shown in the figure).

Therefore, the control unit 44 on the detection circuit 40 can calculate the rotation angle value of the striking shaft 35 according to the angle position of the second pulse obtained by the angle sensor 42 sensed by the driving unit 20 relative to the position of the first pulse.

For example, when the lock piece (such as screw, nut...) is screwed into the screw hole, the head of the lock piece is not attached to the screw hole, so the driving unit 20 drives the oil pressure pulse type torque generating unit 30 to drive the striking shaft 35 to rotate together (and The socketed lock), and the hydraulic pulse-type torque generating unit 30 does not generate pulses. When the head of the lock piece fits the screw hole, the lock piece begins to receive resistance (reaction force, which is reflected to the striking shaft 35), and the oil pulse type torque generating unit 30 generates pulses. Assuming that the angular position of the first pulse is 0 degrees, The positions of the subsequent pulses are 380, 755, 1125, 1490, 1853, 2215 in sequence, and the rotation angle generated by a single pulse is in sequence:

380-360=20;

755-380-360=15;

1125-755-360=10;

1490-1125-360=5;

1853-1490-360=3;

2215-1853-360=2;

The sum of the rotation angles is 55.

After multiple accumulations, until the last stop (that is, the angle does not change), the sum of the superpositions is the sum of the rotations of the striking shaft 35 and the sum of the rotations of the locking member sleeved on the striking shaft 35.

<Torque calculation>

When a single pulse is generated, the greater the angle change of the rotation of the striking shaft 35 (the angle change a generated by a single pulse), the smaller the torque generated. On the contrary, single When the secondary pulse is generated, the smaller the angular change of the rotation of the striking shaft 35 (the angular change a generated by a single pulse), the greater the torque generated.

The larger the rotation speed change ΔV (or the rotation speed difference) is, the more energy is transmitted to the striking shaft 35 and the greater the torque produced. Conversely, the smaller the speed change ΔV, the less energy is transmitted to the striking shaft 35, and the smaller the torque produced.

By judging that the angle sensor 42 senses the angular position, rotation speed, and rotation speed difference of the drive unit 20 for each pulse, the torque can be calculated and the coefficient can be automatically calibrated; the coefficient can be adjusted and controlled by the following formula 1 with the detection circuit 40 The unit 22 can selectively control the drive unit 20 and the power supply unit 10 to form a short circuit (ON) or open circuit (OFF) to achieve a stopping effect, and can control the torque value output by the striking shaft 35.

F=p/[(1+a*m)*(1-△V*n)]…………(Formula 1)

In the above formula, p, m, and n are adjustment coefficients, which are adjusted according to different thread characteristics. After the adjustment coefficient is set, only need to enter a: rotation angle and △V speed difference into the formula to calculate the torque F.

<Instructions for automatic coefficient calibration>

When the electric oil pressure pulse tool of the present invention needs to be calibrated, the adjustment coefficient in formula 1 is adjusted to make the calculation result more accurate. The coefficient can be manually input to the accurate torque value read on the torsion tester, and then transmitted (wired or wireless ) To the control unit 44 of the detection circuit 40, the detection circuit 40 calculates according to the correct result to obtain a new adjustment coefficient;

Convert formula 1 to

F*(1+a*m)*(1-△V*n)-p=0…………(Formula 2)

Formula 2 is a ternary quadratic equation, so there may be no solution, and it is converted to an inequality equation. The absolute value is required to be less than 0.1, and it is converted to Formula 3 again ｜F*(1+a*m)*(1-△V*n)-P｜<0.1…………(Formula 3)

Among them, F, a, △V can be read by the torsion tester and the angle sensor 42, for example, after three tests, the following three formulas can be obtained: |F1*(1+a1*m)*(1-△V1 *n)-p｜<0.1

｜F2*(1+a2*m)*(1-△V2*n)-p｜<0.1

｜F3*(1+a3*m)*(1-△V3*n)-p｜<0.1

There will be multiple solutions to each of the above equations. We take the solution with the largest value of P. The solution with p, n, and m greater than 0 is the coefficient to be adjusted. Through the experiment, the process is listed as follows: through the angle sensor 42 and The torsion tester reads:

Adjustment factor calculated according to formula 3

The measured results of the electric oil pressure pulse tool of the present invention after calibration are restarted, as shown in the following table

Through the above description, the torque detection method of the electric hydraulic pulse tool of the present invention further includes: a. Inputting parameters to the control unit 44; b. The control unit 44 triggers the driving unit 20 to drive the hydraulic pulse torque generator 30 to link the striking shaft 35; c. The oil pressure pulse type torque generating unit 30 generates a pulse every time it receives resistance, and the speed of the drive unit 20 also changes; c. The angle sensor 42 detects the pulse state of the drive unit 20 (speed change and Angular position); and d. The control unit 44 judges whether it meets the setting according to the pulse state, and if it meets the setting, it adjusts the action of the drive unit 20.

The above-mentioned pulse state includes the total number of pulses from the first pulse to the last pulse after the start pulse.

The above-mentioned pulse state includes the sum of the rotation angles of the striking shaft 35, The control unit 44 counts the number of pulses and the accumulation of the rotation angle of the striking shaft 35 caused by every two adjacent pulses.

The aforementioned pulse state includes the angle of rotation of the striking shaft 35 caused by a single pulse, and the control unit 44 obtains the value of the rotation angle of the striking shaft 35 caused by every two adjacent pulses.

The above-mentioned pulse state includes the change of the rotation speed of the driving unit 20 before and after a single pulse. The angle sensor 42 detects the rotation speed change value of the driving unit 20 between before and after the single pulse by the control unit 44.

The above-mentioned pulse state includes the time of each pulse point.

The above description is only the preferred embodiments of the present invention. It is intended to clarify the characteristics of the present invention and is not intended to limit the scope of the embodiments of the present invention. Those skilled in the art make equal changes based on the present invention. , And changes well known to those skilled in the art should still fall within the scope of the present invention.

B: Shell

10: Power supply unit

20: drive unit

30: Hydraulic pulse torque generating unit

35: Strike axis

40: detection circuit

46: Control Panel

Claims (8)

An electric oil pressure pulse tool, comprising: a power supply unit; a driving unit electrically connected to the power supply unit; an oil pressure pulse type torque generating unit connected to the driving unit and driven to generate repeated impacts, each impact drives the drive The unit undergoes a load to produce a rotation speed change; and a detection circuit is electrically connected to the power supply unit and the drive unit to control the operation of the drive unit according to the change in the rotation speed of the drive unit. It includes an angle sensor set corresponding to the drive unit and an and Control unit for electrical connection of angle sensor. For the electric oil pulse tool described in item 1 of the scope of patent application, the detection circuit further includes a control panel electrically connected to the control unit. A torque detection method for an electric oil pressure pulse tool, used to control the electric oil pressure pulse tool of request item 1 or 2, including: a. Input parameters to the control unit; b. The control unit triggers the driving unit to drive the oil pressure pulse type The torque generator is linked to the striking shaft; c. The hydraulic pulse-type torque generating unit generates a pulse every time it receives resistance, and the rotation speed of the drive unit also changes; c. The angle sensor detects the pulse state of the drive unit (operation changes) );as well as d. The control unit judges whether it meets the setting according to the pulse state, and if it meets the setting, it adjusts the operation of the drive unit. As described in item 3 of the scope of patent application, the torque detection method of an electric hydraulic pulse tool, wherein the pulse state includes the total number of pulses from the first pulse to the last pulse. The torque detection method of the electric hydraulic pulse tool described in the third item of the scope of patent application, wherein the pulse state includes the sum of the rotation angles of the striking shaft after the pulse starts, and the control unit counts the number of pulses and all pulses caused the rotation angle of the striking shaft The accumulation. The torque detection method of the electric hydraulic pulse tool described in item 3 of the scope of patent application, wherein the pulse state includes the angle of the rotation of the striking shaft caused by a single pulse, and the control unit obtains the striking shaft caused by every two adjacent pulses. Rotation angle value. For the torque detection method of the electric hydraulic pulse tool described in item 3 of the scope of patent application, the pulse state includes before and after a single pulse, and the rotation speed of the drive unit is changed by the control unit before and after the single pulse The angle sensor detects the change in the rotational speed of the drive unit. For the torque detection method of the electric hydraulic pulse tool described in item 3 of the scope of patent application, the pulse state includes the time of each pulse point.

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