According to the principle of action, nail guns can be divided into two categories: direct acting nailers and indirect nailing devices.
Direct acting nailer
The direct acting nailer is to directly apply the gunpowder gas to the nail to push the nail movement. Therefore, the nail has a high speed (about 500 m/s) and kinetic energy when flying away from the nail tube.
Indirect nail shooter
The indirect effect of the gunner's gunpowder gas does not directly act on the nail, but acts on the piston in the nailer, and energy is transmitted to the nail through the piston. Thus, the speed at which the nail is removed from the staple tube is low. The speed of the nails emitted by the direct and indirect nailers is very different; the mass of the nail is m, the speed of the nail of the high speed nailer is Vg, and the speed of the nail of the low speed nailer is yd. The mass of the piston rod is M, then the kinetic energy of the high and low speed nailers are:
Wg-l / 2mVg 2
Wd=l / 2(m + M)Vd 2
When fixing the same conditions, you can think of:
Ie 1 / 2mVg2 = 1 / 2 ( m + M) Vd 2
Since the mass M of the piston rod is 5-15 times the mass m of the nail, take M= 10 m.
1 / 2mVg2 = 1 / 2 ( m + 10m ) Vd 2
Vg / Vd=3 . 32
It can be seen that the speed at which the nailer is directly applied is more than three times the speed of the nailing of the nailer. And it is not difficult to see that for indirect action nailers. The energy generated by the firing of the nail is decomposed into two parts: the energy of the nail and the volume of the piston rod, and the energy of the piston rod accounts for the majority. Since the piston rod can only move in the nail tube, the direction can be controlled by the operator through the nail gun, and when the nail touches the base body, the resistance is encountered, the speed is lowered, and the piston rod transmits energy to the nail to fix. If the power of the projectile is too high, the energy is too large, and the nail is drilled too deep, then the piston rod is immediately blocked by the nail tube and the stop ring, and the nail and the piston stop moving. Then the excess energy is all consumed on the nail shooter. Due to the difference in principle and structure between the direct acting nailer and the indirect nailing device, the effect is also very different. The former has obvious weaknesses. In some cases, not only the fixing reliability is poor, but also the matrix structure is easily broken. In serious cases, it may cause personal safety accidents.
Therefore, except for special cases, other generally do not use the direct action nailer, but use the indirect action nailer. Reliability and security are far superior to the former. From zoning, and some nail is only for the repair of metallurgical industry ingot mold, fixing insulating panels and hang tags, special Sheding named, and some to all industries, it is also known universal Sheding.