Electric air spring nail gun with air pressure alarm function and air pressure alarm method thereof

Abstract

The invention discloses an electric air spring nail gun with an air pressure alarm function and an air pressure alarm method, the nail gun comprises a control system, the control system comprises a controller, a sensor and a control switch, the output end of the sensor and the output end of the control switch are electrically connected with the input end of the controller, the output end of the controller is connected with a motor, and the motor is controlled by the controller; the sensor comprises a current sensor and a voltage sensor, the current sensor is used for feeding back output current of the battery pack and / or the motor, and the voltage sensor is used for feeding back output voltage of the battery pack and / or the motor; an algorithm in the controller associates the voltage and current values with the pressure value of the air cylinder, the pressure value is compared with a set pressure threshold value, and when the pressure value exceeds the threshold value, an alarm is given to remind a user.

Description

TECHNICAL FIELD

[0001] The present application relates to a kind of electric air spring nail gun with air pressure alarm function, belong to nail gun technical field. BACKGROUND

[0002] Fastener striking tool such as nail gun is driven by compressed gas power to drive the piston in the cylinder to drive the punch pin to drive the nail into the workpiece, which is a common tool in the construction and decoration industries. Due to the safety problems of nail guns using gas as power source, electric air spring nail guns have gradually replaced them in recent years.

[0003] During use, the size of the energy required by the air spring nail gun to drive the nail mainly depends on the size of the gas pressure in the cylinder. When the gas pressure in the cylinder is too small or there is gas leakage, the motor drives the piston to compress the gas to make the punch pin disengage from the engagement of the lifting mechanism, and the energy of the punch pin to drive the nail is too small to drive the nail into the medium. Therefore, the gas pressure in the cylinder needs to be increased to an appropriate pressure. However, due to the structural design and material limitations of the cylinder, excessive pressure may cause structural damage. The gas pressure in the cylinder is affected by many factors such as temperature and gas leakage, and the gas pressure in the cylinder changes greatly. At this time, the cylinder needs to be detected, and the pressure needs to be alarmed when it is too low, and the pressure needs to be protected when it is too high. At present, the detection and protection of this function in similar fields are mainly achieved by installing additional gas pressure detection devices sensors. This method needs to install additional gas pressure detection devices at the cylinder valve core, which increases the cost and complicates the installation and maintenance, and cannot effectively protect the cylinder. SUMMARY

[0004] The present application aims to overcome the problems in the prior art and provide an electric air spring nail gun with air pressure alarm function, which can accurately detect the air pressure of the air spring nail gun and prevent the structure of the air spring nail gun from being damaged due to excessive air pressure.

[0005] To solve the above technical problems, the present application provides an electric air spring nail gun with air pressure alarm function, which comprises:

[0006] A housing is provided with a battery pack socket;

[0007] A gas storage chamber is provided in the housing and forms a gas storage space;

[0008] A cylinder is provided with the gas storage chamber, for driving the striking assembly from the top dead center to the bottom dead center;

[0009] A striking assembly can reciprocate between the top dead center position and the bottom dead center position and drive the fastener into the workpiece. The striking assembly comprises a piston and a punch pin, and the piston is slidably inserted into the inner wall of the cylinder.

[0010] A lifting mechanism for moving the striking assembly from the bottom dead center to the top dead center reset, the lifting mechanism comprising a motor and a lifting wheel, the motor driving the lifting wheel to rotate;

[0011] A control system comprising a controller, a sensor and a control switch, the output of the sensor and the control switch being electrically connected to the input of the controller, the output of the controller being connected to the motor, the motor being controlled by the controller;

[0012] The sensor comprises a current sensor and a voltage sensor, the current sensor being used to feedback the output current of the battery pack and / or the motor, and the voltage sensor being used to feedback the output voltage of the battery pack and / or the motor; the algorithm in the controller associates the voltage and current values with the pressure value of the cylinder, and compares the pressure value with the set pressure threshold value, and issues an alarm when the pressure value exceeds the threshold value to remind the user.

[0013] The present application also provides a pneumatic alarm method for an electric air spring nail gun, comprising the following steps:

[0014] 1) Calibrating the normal air pressure threshold of the nail gun cylinder to confirm the maximum air pressure value p max and the minimum air pressure value p min of the normal working of the nail gun;

[0015] 2) Calculating the output power W out of the lifting mechanism through the input power P in of the motor, and obtaining the air pressure p i of the nail gun according to the output power W out ;

[0016] 3) Judging whether the air pressure value p i satisfies p min <p i <p max , if yes, the nail gun is running normally, and if not, an alarm is issued.

[0017] Further, the maximum air pressure value p max =(1.2-1.3) p 均 and the minimum air pressure value p min =(0.5-0.7) p 均 of the normal working of the nail gun in 1) are set as the standard air pressure value p 均 of each nail gun at the factory.

[0018] Further, the step of calibrating the normal air pressure threshold of the nail gun cylinder is as follows:

[0019] In the state that the nail gun is not initialized, the work done by the lifting mechanism in the normal n-gun driving state of the nail gun is recorded as W1, W2, … Wn Calculate the average work W done in nailing. 均 Then W 均 This represents the average work done by the nail gun under normal air pressure.

[0020] When the lifting mechanism moves the striking component from the bottom dead center to the top dead center, the piston pressure is p. i If the cross-sectional area of ​​the piston is S, then the work W done by the striking assembly in each nail-driving stroke is... i =p i S×L, where L is the stroke of the piston from top dead center to bottom dead center, and n is an integer greater than 3;

[0021] but Since S and L are constant values, p i It can be directly calculated based on W. 均 Therefore, under normal nail-driving conditions, the air pressure value of the cylinder during the normal nail-driving process of the first n gun cylinders is... The maximum air pressure value p for normal operation of the nail gun max =(1.2-1.3)p 均 Minimum air pressure value p min =(0.5-0.7)p 均 .

[0022] Furthermore, p min =0.6W 均 The calibrated maximum air pressure value p max =1.3W 均 .

[0023] Furthermore, the specific steps for 2) are as follows:

[0024] (2.1) Calculate the input power W of the motor using the voltage U and current I during normal nail shooting. in =I×U×t, where t is the time it takes for the lifting mechanism to push the striking component from the lower dead center to the upper dead center;

[0025] (2.2) Through the input power W of the motor in Calculate the output power W of the lifting mechanism out =η×W in , where η is the efficiency of the motor;

[0026] (2.3) Based on the output power P of the lifting mechanism out The work W done by the lifting mechanism in pushing the striking component from the bottom dead center to the top dead center is calculated. out =η×W in ;

[0027] When the lifting mechanism moves the striking component from the bottom dead center to the top dead center, the piston pressure is p.i ,but Since t, S, and L are all known quantities; therefore, p i and W out They are positively correlated.

[0028] Furthermore, p max =1.3p 均 and minimum air pressure value p min =0.6p 均 p 均 The standard air pressure value set for each nail gun at the factory.

[0029] Furthermore, n = 5.

[0030] The beneficial effects of the present invention are: (1) By monitoring the air pressure in the nail gun cylinder through the linear relationship between power and air pressure, the present invention does not require the installation of an additional pressure detection device to complete the low pressure / high pressure alarm, and there is no disadvantage of increasing installation and maintenance costs.

[0031] (2) The present invention uses multi-parameter fusion to detect the air pressure of the cylinder, which can improve the accuracy of air pressure detection and reduce false alarms. Attached Figure Description

[0032] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. The drawings are provided for reference and illustration only and are not intended to limit the present invention.

[0033] Figure 1 This is a schematic diagram of a gas spring nail gun;

[0034] Figure 2 This is a flowchart illustrating the air pressure anomaly detection method in an embodiment of the present invention;

[0035] Figure 3 As an embodiment of the present invention, W in The calculation flowchart;

[0036] Figure 4 This is a diagram showing the motor parameters of an embodiment of the present invention;

[0037] In the diagram: 1. Casing, 2. Battery pack, 3. Gas chamber, 4. Cylinder, 5. Piston, 6. Strike pin, 7. Motor, 8. Lifting wheel. Detailed Implementation

[0038] In the following description of the present invention, the terms "upper", "lower", "front", "rear", "left", "right", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not mean that the device must have a specific orientation.

[0039] To make the technical means, creative features, objectives and effects of this invention easier to understand, the invention will be further described below with reference to specific illustrations.

[0040] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of the invention.

[0041] like Figure 1 As shown, an electric gas spring nail gun with a pneumatic alarm function according to the present invention includes:

[0042] Housing 1, housing 1 is provided with a slot for battery pack 2;

[0043] Gas storage chamber 3 is located inside shell 1 and forms a gas storage space;

[0044] Cylinder 4, which is connected to air chamber 3, is used to drive the striking component from the top dead center to the bottom dead center.

[0045] The striking assembly is capable of reciprocating between the upper dead center position and the lower dead center position to drive the fastener into the workpiece; the striking assembly includes a piston 5 and a striking pin 6, the piston 5 being slidably inserted into the inner wall of the cylinder 4;

[0046] A lifting mechanism is used to move the striking component from the lower dead point to the upper dead point for reset. The lifting mechanism includes a motor 7 and a lifting wheel 8, and the motor 7 drives the lifting wheel 8 to rotate.

[0047] The control system includes a controller, sensors, and control switches. The output terminals of the sensors and control switches are electrically connected to the input terminals of the controller. The output terminal of the controller is connected to the motor 7, and the motor 7 is controlled by the controller.

[0048] The sensors include a current sensor and a voltage sensor. The current sensor is used to provide feedback on the output current of battery pack 2 and / or motor 7, and the voltage sensor is used to provide feedback on the output voltage of battery pack 2 and / or motor 7. The algorithm in the controller correlates the voltage and current values ​​with the pressure value of cylinder 4 and compares the pressure value with a set pressure threshold. When the pressure value exceeds the threshold, an alarm is issued to remind the user.

[0049] This invention also proposes a method for air pressure alarm of an electric gas spring nail gun, comprising the following steps:

[0050] (1) Calibrate the normal air pressure threshold of the nail gun cylinder. The maximum air pressure value p for normal operation of the nail gun is determined according to the standard air pressure value set at the factory for each nail gun. max and minimum air pressure value p min Calibrate the nail gun to determine its maximum air pressure value p for normal operation. max=(1.2-1.3)p 均 and minimum air pressure value p min =(0.5-0.7)p 均 p 均 The standard air pressure value set for each nail gun at the factory.

[0051] Because each nail gun has structural errors at the factory, the stroke of the firing pin, the resistance of the lifting mechanism, etc., are not completely consistent. This results in a certain deviation between the normal operating air pressure of each nail gun and the standard air pressure value. Therefore, the maximum normal operating air pressure value p for each nail gun is... max and minimum air pressure value p min They are all different. This invention uses the following method to determine the maximum air pressure value p of each nail gun under normal operating conditions. max and minimum air pressure value p min The specific steps are as follows:

[0052] With the nail gun uninitialized, calculate the work done by the lifting mechanism during the first 5 normal nail-driving strokes, denoted as W1, W2, ... W5, and calculate the average work W of the nail-driving strokes. 均 Then W 均 This represents the average work done by the nail gun under normal air pressure.

[0053] When the lifting mechanism moves the striking component from the bottom dead center to the top dead center, the piston pressure is p. i If the cross-sectional area of ​​the piston is S, then the work W done by the striking assembly in each nail-driving stroke is... i =p i S×L, where L is the stroke of the piston from top dead center to bottom dead center;

[0054] but Since S and L are constant values, therefore p i It can be directly calculated based on W. 均 Therefore, under normal nail-driving conditions, the air pressure value of the cylinder during the first 5 nail-driving cycles is...

[0055] At this time p 均 It overcomes the deviation of each nail gun from the standard air pressure value, and will p 均 The calibrated air pressure standard value overcomes the differences between each nail gun, making the air pressure alarm information more accurate.

[0056] (2.1) Calculate the input power W of the motor using the voltage U and current I during normal nail shooting. in =I×U×t, where t is the time it takes for the lifting mechanism to push the striking component from the lower dead center to the upper dead center;

[0057] (2.2) Through the input power W of the motor in Calculate the output power W of the lifting mechanism out =η×W in , where η is the efficiency of the motor;

[0058] Under normal circumstances, the maximum air pressure value p for normal operation of the nail gun is set. max =1.3p 均 and minimum air pressure value p min =0.6p 均 .

[0059] (2.3) Based on the output power P of the lifting mechanism out The work W done by the lifting mechanism in pushing the striking component from the bottom dead center to the top dead center is calculated. out =η×W in .

[0060] Therefore, Since t, S, and L are all known quantities; therefore, p i and W out Positive correlation;

[0061] p i With W in The correlation values ​​can be generated by creating a table from pre-measured historical data and writing it into the program. The values ​​can then be transferred to the program by transcribing the table. i With W in Relatedly, it could also be related to the air pressure value p during the use of the nail gun. i Dynamic calculations are performed. Since the motor efficiency η under normal nail-driving air pressure is significantly higher than that under low and high air pressure, and the change in η under normal nail-driving air pressure is small, therefore the air pressure p... i With the input power W of the motor in They are positively correlated.

[0062] (4) Determine the air pressure value p i Does p satisfy? min <p i <p max If yes, the nail gun will operate normally; otherwise, an alarm will be triggered.

[0063] like Figure 2 and Figure 3 As shown, taking a nail gun as an example, the standard air pressure of a nail gun is 70 PSI. Therefore, the maximum normal air pressure is set to 90 PSI and the minimum to 60 PSI. After the motor starts running, the current signal I and voltage signal U are continuously acquired using an oscilloscope to calculate the input power P. The input power W done by the motor is then calculated cumulatively in 1ms increments. in And determine W inCheck if the corresponding air pressure value pi is between 60PSI and 90PSI. If it is, the nail gun will operate normally; otherwise, an alarm signal will be issued.

[0064] like Figure 4 As shown in the diagram, C4 represents current, C5 represents voltage, and F1 represents the motor's input power. Since the average power of the striking pin is 326.8W and the running time is 432ms, then W... in =141177.6WMs, corresponding to a cylinder air pressure of 90PSI. Since the critical value has been reached, the nail gun sounds an alarm.

[0065] This invention eliminates the need for additional pressure sensors, monitoring air pressure solely by tracking current and voltage values. It also avoids the inaccuracies associated with monitoring only a single variable, enabling the controller to accurately identify the air pressure status of the cylinder and determine whether the nail gun is operating normally.

[0066] This invention correlates power and air pressure, detects the input power of the motor to achieve air pressure detection and early warning, effectively improving the accuracy and stability of air pressure detection, reducing false alarm rate, and enhancing user experience.

[0067] The above description is merely a preferred embodiment of the present invention, showing and describing the basic principles, main features, and advantages of the present invention. It is not intended to limit the scope of patent protection of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. In addition to the above embodiments, the present invention may have other implementations without departing from the spirit and scope of the invention. Various changes and modifications to the present invention are possible, and all technical solutions formed by equivalent substitutions or equivalent transformations fall within the scope of protection claimed by the present invention. The scope of protection of the present invention is defined by the appended claims and their equivalents. Technical features not described in the present invention can be implemented by or using existing technology, and will not be elaborated here.

Claims

1. An electric gas spring nail gun with a pneumatic alarm function, comprising: The housing has a slot for the battery pack; A gas storage chamber is disposed within the shell and forms a gas storage space; A cylinder, which communicates with the air storage chamber, is used to drive the striking assembly from the top dead center to the bottom dead center. The striking assembly is capable of reciprocating from the upper dead center position to the lower dead center position and driving the fastener into the workpiece; the striking assembly includes a piston and a striking pin, the piston being slidably inserted into the inner wall of the cylinder; A lifting mechanism is used to move the striking component from the lower dead point to the upper dead point for resetting. The lifting mechanism includes a motor and a lifting wheel, and the motor drives the lifting wheel to rotate. The control system includes a controller, sensors, and control switches. The output terminals of the sensors and control switches are electrically connected to the input terminals of the controller. The output terminal of the controller is connected to a motor, and the motor is controlled by the controller. The features are as follows: the sensor includes a current sensor and a voltage sensor, the current sensor is used to feed back the output current of the battery pack and / or the motor, and the voltage sensor is used to feed back the output voltage of the battery pack and / or the motor; the algorithm in the controller associates the voltage and current values ​​with the pressure value of the cylinder, and compares the pressure value with a set pressure threshold, and issues an alarm to remind the user when the pressure value exceeds the threshold.

2. The air pressure alarm method for an electric gas spring nail gun with air pressure alarm function according to claim 1, characterized in that, Includes the following steps: 1) Calibrate the normal air pressure threshold of the nail gun cylinder to confirm the maximum air pressure value p for normal operation of the nail gun. max and minimum air pressure value p min ; 2) Through the input power P of the motor in Calculate the output power W of the lifting mechanism out And based on the output power W out The air pressure p of the nail gun is obtained. i ; 3) Determine the air pressure value p i Does p satisfy? min <p i <p max If yes, the nail gun will operate normally; otherwise, an alarm will be triggered.

3. The air pressure alarm method for a gas spring nail gun according to claim 2, characterized in that: The maximum air pressure value p for normal operation of the nail gun as described in 1) max =(1.2-1.3)p 均 and minimum air pressure value p min =(0.5-0.7)p 均 p 均 The standard air pressure value set for each nail gun at the factory.

4. The air pressure alarm method for an electric gas spring nail gun with air pressure alarm function according to claim 2, characterized in that: The steps for calibrating the normal air pressure threshold of the nail gun cylinder are as follows: With the nail gun uninitialized, calculate the work done by the lifting mechanism during the first n nail shots in normal firing mode, denoted as W1, W2, ... W. n Calculate the average work W done in nailing. 均 Then W 均 This represents the average work done by the nail gun under normal air pressure. When the lifting mechanism moves the striking component from the bottom dead center to the top dead center, the piston pressure is p. i If the cross-sectional area of ​​the piston is S, then the work W done by the striking assembly in each nail-driving stroke is... i =p i S×L, where L is the stroke of the piston from top dead center to bottom dead center, and n is an integer greater than 3; but Since S and L are constant values, p i It can be directly calculated based on W. 均 Therefore, under normal nail-driving conditions, the air pressure value of the cylinder during the normal nail-driving process of the first n gun cylinders is... The maximum air pressure value p for normal operation of the nail gun max =(1.2-1.3)p 均 Minimum air pressure value p min =(0.5-0.7)p 均 .

5. The air pressure alarm method for an electric gas spring nail gun with air pressure alarm function according to claim 2, characterized in that: p min =0.6W 均 The calibrated maximum air pressure value p max =1.3W 均 .

6. The electric gas spring nail gun with air pressure alarm function according to claim 4, characterized in that: 2) The specific steps are as follows: (2.1) Calculate the input power W of the motor using the voltage U and current I during normal nail shooting. in =I×U×t, where t is the time it takes for the lifting mechanism to push the striking component from the lower dead center to the upper dead center; (2.2) Through the input power W of the motor in Calculate the output power W of the lifting mechanism out =η×W in， Where η is the efficiency of the motor; (2.3) Based on the output power P of the lifting mechanism out The work W done by the lifting mechanism in pushing the striking component from the bottom dead center to the top dead center is calculated. out =η×W in ; When the lifting mechanism moves the striking component from the bottom dead center to the top dead center, the piston pressure is p. i ,but Since t, S, and L are all known quantities; therefore, p i and W out They are positively correlated.

7. The air pressure alarm method for an electric gas spring nail gun with air pressure alarm function according to claim 3 or 4, characterized in that: p max =1.3p 均 and minimum air pressure value p min =0.6p 均 p 均 The standard air pressure value set for each nail gun at the factory.

8. The air pressure alarm method for an electric gas spring nail gun with air pressure alarm function according to claim 4, characterized in that: n＝5。

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