Nailer vibration handle optimization design and finite element analysis

Zhou Ruili Bi Xiangqiu

 

(1 Taizhou, Zhejiang Vocational and Technical College of Mechanical and Electrical Engineering, 318000; 2. Zhejiang Taizhou River Industrial Co., Ltd., Taizhou 317500)

 

Abstract: At present, pneumatic tools vibration handle design has attracted wide attention. This article is a gas nailer as the research object, through the design of the handle for vibration damping pressure test to finite element software ANSYS Workbench as computing platform, its analysis of the entire gun vibration acceleration, vibration handle for the optimization of gas nailer designed to provide a theoretical basis.

 

Keywords: Pneumatic Nailer finite element method structural optimization

 

1 Introduction

 

Air Nailer when in use, the handle will have impact, impact force for a long time effect, endangering the health of the operator. Therefore, the gas nailer vibration handle design has attracted wide attention. Currently, the major domestic package using a layer of rubber in the handle method of damping material. However, the thickness of the rubber material the handle there is a certain range, too large bold handle, small damping effect is not obvious. Therefore, we propose choosing the right holster - Handle with structures for vibration damping, and the design of the structure of simulation studies for the gas nailer vibration handle design provides theoretical guidance.

 

2 vibration handle optimal design

 

Gas nailer handle is designed not only to ensure the strength requirements of working conditions, that maintain the high pressure gas flow in its interior, but also consider the operator gripping comfort; leather are both closely with the outer surface of the handle while ensuring comfort grip, can play a damping effect. Thus, in the optimal design, the handle and holster can not change the apparent size is too large, meanwhile, must be improved grip strength check, in order to meet working condition requirements.

 

Based on the above analysis, can not increase the overall thickness of the leather, the surface design of the handle may be considered a different number of slots, while the inner surface of leather surfaces corresponding number of steps in order to ensure a solid fit, the handle and the other parts of the size of holster is consistent with the original design, that is, by increasing the local thickness of leather, to enhance the damping effect. Shown in Figure 1-3.

 

3 gun high pressure test finite element analysis

 

3.1 Modeling

 

For the modified holster - handle structure, you first need to verify the effective thickness of the handle can meet the strength requirements of the work, and then the whole structure of the modified gun vibration acceleration analysis. Validation method is high-intensity pressure test. Mainly for the high-pressure test gas nailer housing (gun body with aluminum cap, air intake cover) carried out to design a gas nailer housing through the following tests: Apply 5 times the maximum working pressure of the hydraulic and Paul pressure 3 minutes during the air nailer housing can rupture and leaking. This article is carried out on the gun handle retrofit design, so only the handle on the gun body parts especially the high-pressure test of the finite element simulation, checking the gun body structure meets the high water pressure test requirements.

 

High water pressure test of the finite element analysis using static analysis methods, geometric model shown in Figure 1-3, die-cast aluminum gun body ZL104, give all the gun body to withstand high internal pressure 4.2MPa pressure applied to the surface boundary conditions gun and other external auxiliary test fixture with the Department, displacement constraints imposed boundary conditions. Three design schemes gun finite element model is shown in 4 to 6.

 

3.2 Analysis of results

 

Gun high pressure test of the finite element analysis results shown in Table 1, the strain results shown in Figure 10-12. Based on the results, we can see the maximum stress and the maximum strain of the switch in the gun body around the corner of the mounting hole, and the presence of grooves on the handle handle the stress and strain distribution in other locations the presence of. Wherein the program three Whole gun maximum stress value for 65.984MPa, this value is lower than the gun body yield strength of the material used. The biggest gun three scenarios were between 0.0009 ~ 0.001mm/mm strain between the gun body as a whole should be less variable in the high-pressure test sealing requirements can be guaranteed, will not water leakage. Because of the high water pressure test procedure is similar to the static process, so three design schemes gun body strength can meet high water pressure test requirements.

 

4 whole gun vibration acceleration finite element solution

 

Soft body dynamics method using the three design options for the whole gun vibration acceleration transient solver. Three design solutions to solve the same settings. In the solution process, a plurality of sub-step through the settings to simulate the impact force is applied to the end of the gun clip in the handle position caused by the vibration acceleration size. Structure of the program were the three models were whole gun vibration acceleration and acceleration RMS value. Gas nailer handle vibrations transmitted to the main body through the middle finger, so the index finger of the three central damping solution vibration acceleration same location are compared in Table 2.

 

5 Conclusions

 

Through the overall design of the three guns of the vibration acceleration calculated results, the conclusion: With the increase of the slot structure, the handle is passed to the hands of the vibration acceleration significantly reduced, increasing the thickness of leather partial solution is effective vibration The. On the other hand, an increase of only holster slot structure under the direction of the surface of the local thickness, the opponent does not affect comfort grip. Thus, to ensure the strength of the premise gun may be used to increase the slot structure by a method to enhance the damping effect.