CN104234113A - Air valve curtain of mini excavator - Google Patents

Abstract

The invention discloses an air valve curtain of a mini excavator. The air valve curtain comprises an air guiding pipe and an air blower; the air valve curtain is characterized by also comprising an U-shaped support, wherein the U-shaped support comprises U-shaped pipelines and a ceiling, the U-shaped pipelines are connected through the ceiling, vent holes are formed in the U-shaped pipelines, the U-shaped pipelines are arranged on an upper frame of the mini excavator, and the U-shaped support is connected with the air blower through the air guiding pipe. According to the air valve curtain of the mini excavator, disclosed by the invention, when the mini excavator works, air is blown in the air guiding pipe by the air blower, air flow is formed, the air flow enters the U-shaped pipelines and is finally blown out through the vent holes, an air curtain is formed around an operator, thus protection on the operator is formed, and dust, haze, raindrops and the like in an external environment are effectively blocked from disturbing the operator.

Description

A kind of microminiature excavator valve curtain

Technical field

The present invention relates to a kind of excavator cab, especially the driver's cabin of microminiature excavator.

Background technology

The cabin design of current excavator has two kinds of situations.The first is mainly used in the very poor large excavator of working environment.Adopt totally enclosed type driver's cabin, provide comfortable working environment for operating personnel and ensured the safety of operating personnel.The shortcoming of this driver's cabin is that complex structure, cost are high.The second is the driver's cabin of microminiature excavator, and its driver's cabin major part is open type, and this driver's cabin can not provide any guarantee for operating personnel.The present invention is mainly for microminiature excavator.

Summary of the invention

Goal of the invention: the object of the invention is to better protect operating personnel, from the interference of dust granule in external environment and foreign matter when especially working, to ensure that operating personnel have comfortable working environment, avoids the generation of contingency.

Technical scheme: in order to solve the problem, the invention provides a kind of valve curtain be arranged on microminiature excavator, it comprises guide duct, blast fan, characterized by further comprising U-shaped support, U-shaped support comprises U-tube road and ceiling, and U-tube road is connected by ceiling, U-shaped built in pipeline air vent, and be arranged in microminiature excavator upper frame, U-shaped support connects blast fan by guide duct.By such device, blast fan blasts guide duct air, forms air-flow, then enters U-shaped support, finally from air vent blowout, forms air curtain protection in the surrounding of operating personnel.

As a further improvement on the present invention, described blast fan is connected with digger engine, when excavator is started working, just can form air curtain protection in the surrounding of operating personnel.Just can start valve curtain when excavator is started working, be easy to operation.Can also consumptive material be reduced, reduce costs.

As a further improvement on the present invention, described air vent is evenly distributed on U-tube road, and the air curtain that valve curtain can be made to blow out is evenly smooth, thus reaches better protected effect.

As a further improvement on the present invention, U-shaped support is minimum comprises two U-tube roads, left and right.Adopt this device, structure is simple, just can form protection in operating personnel's surrounding.

Beneficial effect: the protection forming four sides air curtain owing to the invention provides a kind of operating personnel at excavator; effectively can stop the interference to operator such as dust, haze, raindrop in external environment; and consumptive material is few, cost is low, transparency is high, can not have interference to the visual field of operator.

Accompanying drawing explanation

Fig. 1 is overall structure figure of the present invention;

Fig. 2 is the front elevation drawing of the U-shaped support of the present invention;

Fig. 3 is the top view of the U-shaped support of the present invention;

Fig. 4 is the front elevation drawing in U-tube road of the present invention;

Fig. 5 is air-out situation before and after the U-shaped support of the present invention;

Fig. 6 is the force analysis figure of the foreign matter in air;

Wherein, 1, guide duct, 3, digger engine, 4, blast fan, 5, U-shaped support, 6, ceiling, 7, U-tube road, 8, air vent.

Detailed description of the invention

In order to deepen the understanding of the present invention, below in conjunction with embodiment and accompanying drawing, the invention will be further described, and this embodiment only for explaining the present invention, does not form limiting the scope of the present invention.

Be the overall structure figure of a kind of detailed description of the invention of the present invention as shown in Figure 1, Figure 2, Figure 3, Figure 4, comprise guide duct 1, blast fan 4, U-shaped support 5, U-shaped support 5 is comprised two U-tube roads 7 and ceiling 6, two U-tube roads 7 and is connected by ceiling 6, the built-in air vent 8 in U-tube road 7, air vent 8 is evenly distributed on U-tube road 7, and being arranged in microminiature excavator upper frame, U-shaped support 5 connects blast fan 4 by guide duct 1, and blast fan 4 is connected with digger engine 3.When excavator is started working, blast fan 4 blasts guide duct 1 air, forms air-flow, then enters U-tube road 7, finally blow out from air vent 8, forms the protection of uniform air curtain in the surrounding of operating personnel.Effectively can stop the foreign matter of external environment, as dust granule, haze, raindrop etc. are to the interference of operating personnel.

Be illustrated in figure 5 the front and back air-out situation of the U-shaped support 5 of the present invention.After valve curtain starts, in the front and back of valve curtain, form air curtain protection from the air-flow of the air vent 8 at survey and top in both sides, U-tube road 7.

Quality is the force analysis figure that the foreign material of M enter valve curtain region as shown in Figure 6, and this foreign material gravity direction component velocity is V ₂, component velocity that is vertical and gravity direction is V ₁.Valve curtain wind speed degree is V ₀, owing to being dry with blast fan 4, and blast fan 4 wind speed is probably at 20 metre per second (m/s)s, gets V ₀=20m/s;

For foreign material, be subject to an an air pressure F and gravity Mg (g is gravity constant 9.8kg/s^2);

Wherein F is air pressure, when air molecule stroke speed be V2, surface area be the foreign material of S time, suppose through the Δ t time, when the time is very little time, F can be approximated to be definite value, is so obtained by momentum theorem F × t=m × V

F × Δ t=m × (V ₀-V ₂) (m is the gross mass that in the Δ t time, all air molecules clash into foreign material) 1

M=ρ × S × Δ t × (V ₀-V ₂) (ρ is atmospheric density 1.29kg/m^3) 2

Obtained by 1 formula and 2 formulas

F＝ρ×(20-V ₂)×S×(20-V ₂)

Again by Newton's Theorem F=ma, then foreign material are had in vertical direction

$F+\mathrm{Mg}=M\frac{{\mathrm{dV}}_2}{\mathrm{dt}}$

Existing:

$\mathrm{\ρ}\×S\×{(20-V_2)}^2+\mathrm{Mg}=M\×\frac{d{V}_2}{\mathrm{dt}}$

If do not consider under gravitational conditions existing:

$\mathrm{\ρ}\×S\×{(20-V_2)}^2=M\×\frac{d{V}_2}{\mathrm{dt}}$

Suppose that foreign material are that 0 to accelerate to speed be V from speed, the required time is T.

Have ${\∫}_0^V\frac{d{V}_2}{{(20-V_2)}^2}={\∫}_0^T\frac{\mathrm{\ρS}}{M}\mathrm{dt}$

Solve $T=\frac{\frac{1}{20}-\frac{1}{20-V}}{1.29}\×\frac{M}{S}$

Foreign material are from valve curtain tip motions to bottom time and pass through the valve curtain time

Table 1

Illustrate: 1. the height getting valve curtain is L ₁=1m, the effective width L of valve curtain ₀=0.2m.

2. in form, foreign material enter valve curtain V ₁, raindrop speed is multiplied by 10% according to actual falling speed and obtains, if drizzle falling speed is at about 2m/s, therefore the cross stream velocity component entering valve curtain for its 10%, both 0.2m/s.

Time as can be seen from the above table needed for foreign material transverse crossing valve curtain is always greater than foreign material from the time needed for valve curtain top movements to bottom, so foreign material just can be blown away when also not passing over valve curtain.

The foregoing is only preferred embodiment of the present invention, not in order to limit the present invention, within the spirit and principles in the present invention all, any amendment done, equivalent replacement, improvement etc., all should be included in protection scope of the present invention.

Claims (4)

1. a microminiature excavator valve curtain, comprise guide duct (1), blast fan (4), characterized by further comprising U-shaped support (5), U-shaped support (5) comprises U-tube road (7) and ceiling (6), U-tube road (7) is connected by ceiling (6), U-tube road (7) built-in air vent (8), and being arranged in microminiature excavator upper frame, U-shaped support (5) connects blast fan (4) by guide duct (1).

2. microminiature excavator valve curtain according to claim 1, its feature is be connected (3) with the motor of excavator at described blast fan (4).

3. microminiature excavator valve curtain according to claim 1, is characterized in that air vent (8) is evenly distributed on U-tube road (7).

4. microminiature excavator valve curtain according to claim 1, is characterized in that U-shaped support (5) at least comprises two U-tube roads (7).