JPH11180532A - Screw type carrying device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a screw type carrying device capable of carrying soil and sand efficiently even if a pushing-in force does not act on them. SOLUTION: This screw type carrying device comprises a soil and sand transfer device 11 comprising a transfer cylindrical casing which is positioned in a soil and sand intaking chamber 2 of which front end is formed in a shield main body 3 and in which a soil and sand transfer screw vane 22 is disposed, and the first drive part 23 for rotating the soil and sand transfer screw vane 22, a soil and a soil and sand pushing-in device 12 comprising a soil and sand pushing in cylindrical casing 31 connected to a soil and sand intake port 21a formed at the front end part of the cylindrical casing for pushing-in, a pushing in screw vane 32 for pushing soil and sand in the cylindrical casing 31 into the transfer cylindrical casing, and a second rotating drive part 33 for rotating the pushing-in screw vane 32.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a screw-type transfer device in which no pushing force is applied to a space for taking in an object to be transferred.

[0002]

2. Description of the Related Art Generally, in an earth pressure type shield machine, a cutter head is rotatably provided at a front portion of a shield body, and a pressure chamber for taking in earth and sand excavated by the cutter head is formed. A screw type discharging device for discharging earth and sand in the pressure chamber to the outside is provided.

Conventionally, this screw-type earth discharging device has a cylindrical casing connected to a partition wall constituting a pressure chamber, a screw blade for transferring earth and sand rotatably disposed in the cylindrical casing, and It consists of a rotary drive unit that rotates this screw blade, and depressurizes the earth and sand taken into the pressure chamber to the atmospheric pressure side space inside the tunnel behind the shield body while maintaining the earth pressure and water pressure of the ground. While discharging.

[0004]

By the way, when pressure is acting from the ground side into the pressure chamber, the earth and sand is smoothly discharged by the screw blades. However, hard rock such as a mountain tunnel is used. When excavating,
Since the pressure from the ground (pressure at the face), that is, the pushing force is not applied, the pressure in the pressure chamber becomes zero, so that there is a problem that the earth and sand are not sufficiently taken into the cylindrical casing.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a screw-type transfer device that can efficiently transfer a transferred object even when no pushing force is applied.

[0006]

According to another aspect of the present invention, there is provided a screw-type transfer device for transferring an object to be transferred from a lower position to an upper position. A transfer cylindrical casing in which a screw blade for transferring an object to be transferred is disposed and a screw blade for transferring the object to be transferred is disposed therein, and a first rotation drive unit for rotating the screw blade for transfer. , And a cylindrical casing for pushing an object to be transported, which is connected to an intake port formed at one end of the cylindrical casing for transport, and transporting an object in the cylindrical casing for pushing. And a second rotary drive unit for rotating the pushing screw blade for pushing the screw blade into the cylindrical casing.

[0007] According to the above arrangement, the object to be conveyed is forcibly pushed into the transfer device side by using the pushing device, so that no pressure acts on the space for taking in the object to be carried, ie, the pushing force. Can be efficiently conveyed even when does not work.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A screw-type transfer device according to a first embodiment of the present invention will be described below with reference to FIGS.

In this embodiment, a description will be given of a case where the present invention is applied to earth removal provided in a shield machine as an example of a tunnel excavator. As shown in FIG.
The shield machine 1 according to the first embodiment includes a shield body (tunnel excavator body) 3 having a sediment intake chamber (take space section) 2 formed at a front portion thereof, and a shield body 3 in front of the shield body 3. A cutter head 5 rotatably provided on the section via a swivel bearing 4, a rotary drive device (for example, a rotary motor for rotating the cutter head 5 via a gear mechanism) 6 for rotating the cutter head 5, and the shield body Screw-type transfer device (also called screw-type discharging device) arranged in 3
7 is comprised.

As shown in FIGS. 2 and 3, the screw-type transfer device 7 includes a sediment transfer device 11 for transferring the earth and sand to the rear space 8 side of the shield main body 3, and And an earth and sand pushing device 12 for pushing earth and sand into the earth and sand transfer device 11 side.

The sediment transporting device 11 has a front part inserted through the partition wall part 9 forming the sediment intake chamber 2, a sediment intake 21 a formed at the front end part, and a rear end part on the rear space part 8 side. A transfer cylindrical casing 21 having a sediment discharge port 21b formed in a portion thereof; a transfer screw blade 22 having a shaft rotatably disposed in the transfer cylindrical casing 21;
A first rotation drive unit (for example, a hydraulic motor, an electric motor, or the like is used) that is also provided at the rear end of the transfer tubular casing 21 and rotates the transfer screw blade 22.
23 and the sediment discharge port 2 of the transfer tubular casing 21
An opening / closing lid (for example, a lid that opens and closes with a cylinder device) that opens and closes 1b.

The earth and sand pushing device 12 includes a pushing cylindrical casing 31 attached to the earth and sand inlet 21a of the cylindrical transfer casing 21 in a vertical plane and at right angles to the earth and sand transfer direction. , This push-in tubular casing 3
1 comprises a ribbon-like pushing screw blade 32 rotatably arranged in the inside 1, and a second rotation drive unit 33 for rotating the pushing screw blade 32.

The second rotary drive section 33 has a bearing 3 in an annular recess 31a formed in the cylindrical casing 31 for pushing.
An annular band 35, which is rotatably disposed via the screw 4 and has the pushing screw blade 32 fixed to the inner peripheral surface thereof
And a ring gear 36 provided on an outer peripheral portion of the annular band body 35, and a pinion gear 3 meshing with the ring gear 36.
7 and an electric motor (or a hydraulic motor) 39 for rotating the pinion gear 37 via a speed reducer 38. The ring gear 36 and the pinion gear 3
The toothed portion 7 is a beveled tooth. The upper end opening 31b of the pushing tubular casing 31 is formed in a hopper shape so that the earth and sand taken into the earth and sand intake chamber 2 can be easily taken in. Reference numeral 41 denotes a sediment discharge belt conveyor that is disposed in a lining body 42 provided at a rear portion of the shield main body 3 and that conveys sediment to the outside.

The shield body 3 comprises, for example, a front trunk 51 and a rear trunk 52. In order to advance these two trunks 51, 52, a front gripper 53 is provided on the front trunk 51 side. A rear gripper 54 is provided on the rear trunk 52 side, and a shield jack 55 is provided between the two trunks 51 and 52. In addition, the shield body 3
Has been described as being divided into a front body and a rear body, but it is needless to say that it may not be divided.

Hereinafter, using the shield machine 1 described above,
For example, a case where a tunnel having a predetermined angle δ with respect to a horizontal plane is excavated as shown in FIG. 1 will be described. At this time, the inclination angle of the transfer tubular casing 21 with respect to the horizontal plane is φ (90 ° ≧ φ> δ).

The earth and sand excavated by the cutter head 5 as the front body 51 advances in the shield body 3 is
While entering the sediment intake chamber 2, the cutter head 5 is lifted upward by a plurality of scooping plates (not shown) provided at predetermined intervals on the inner peripheral surface of the cutter head 5, and has a hopper-shaped upper opening 31 b. From the cylindrical casing 31 for pushing.

The earth and sand introduced into the pushing tubular casing 31 are forcibly pushed into the transferring tubular casing 21 by the pushing screw blades 32, and the rear space portion 8 is pushed by the transferring screw blades 22. And carried out to a predetermined location by a belt conveyor 41 for carrying out earth and sand.

As described above, since the sediment taken in the sediment intake chamber 2 is forcibly pushed into the sediment transfer device 11 by using the sediment pushing device 12, the pressure in the sediment intake chamber 2 is increased. Even when excavating hard ground such as bedrock that does not act, soil and sand can be efficiently discharged.

Further, since the pushing screw blades 32 are provided in the pushing cylindrical casing 31 of the earth and sand pushing device 12, the arching phenomenon of the earth and sand in the casing or the catching of the earth and sand are prevented. .

Here, an equation representing the pressure P of the earth and sand in the transfer cylindrical casing (hereinafter, simply referred to as a cylindrical casing) is obtained based on FIG. 4 and FIG. become.

FIG. 4 shows the equilibrium of the static force acting on the minute portion 103 of the plug (plastic fluidized excavated earth and sand) in the screw groove portion 102 for one pitch of the screw blade 101.

However, the following assumption is made. The earth and sand are in contact with all surfaces in the cylindrical casing. The shear stress of soil and screw blade surface is constant regardless of pressure.

The pressure is the length of the screw blade groove (x)
Is a function of The gap between the outer diameter of the screw blade and the inner diameter of the cylindrical casing is ignored. Sediment in the screw blade groove acts as a plug.

The symbols and subscripts used in the following formulas are as follows. Symbol D: Screw blade diameter, inner diameter of cylindrical casing H: Screw blade groove depth L: Length of cylindrical casing axial direction P _L : Pressure at any position in screw axial direction P ₀ : Initial pressure (earth pressure in pressure chamber (Water pressure) R: screw blade outer radius W: blade groove width perpendicular to screw blade e: screw blade thickness g: gravitational acceleration t: screw blade pitch x: screw blade groove direction length α: screw blade twist angle η : Ejection efficiency of earth and sand θ: Ejection angle of earth and sand ρ: Bulk density of earth and sand τ: Shear stress φ: Inclination angle of cylindrical casing Subscript b: Screw outer diameter part, casing inner diameter part fp: Screw side pushing side ft: Screw Side drag side m: screw average (center) diameter part r: screw root diameter part First, considering the balance of the force in the screw axis direction, the following equation (1) is obtained. .

[0025]

(Equation 1) Next, considering the balance of the force in the screw shaft rotation direction,
Equation (2) is obtained.

[0026]

(Equation 2) In addition, the equation (2) is divided by the equation (1), and (3) and (4)
By substituting the expressions and rearranging, the expression (5) is obtained.

[0027]

(Equation 3) Next, when the length (x) in the screw groove direction is converted into the length (L) in the screw axis direction by integrating the equation (5),
Equation (6) is obtained.

[0028]

(Equation 4) Substituting the initial conditions L = 0, P _L = P ₀ into equation (6),
C ₀ = 0, and thus equation (7) is obtained.

[0029]

(Equation 5) In the above equation (7), τ _b , τ _r , τf _t , and τ _fp are almost equal, so if these are set to τ, the equation (8) is obtained.

[0030]

(Equation 6) In addition, the discharge efficiency η is calculated as (the amount of excavated sediment of the shield machine /
(The theoretical amount of soil removed by the screw-type transfer device), and is specifically expressed by the following equation (9).

Η = tan θ / (tan θ + tan α _b ) (9) Here, FIG. 5 shows the relationship between the discharge efficiency η and the earth and sand discharge angle θ. In FIG. 5B, when the earth and sand particles at the point A move to the point A 'by one rotation of the screw blade 101, the earth and sand particles move by one pitch t as theoretically, and the discharge efficiency η is 1. It becomes 0. However, if the earth and sand particles at the point A move to the point B due to friction between the screw blades and the cylindrical casing and the earth and sand, the movement distance of the earth and sand particles becomes ηt, and the discharge efficiency η becomes 1.0 or less. When η is 1.0 or more, it indicates that the earth and sand is extruded by the pressure of the pressure chamber.

At this time, the discharge direction of the earth and sand particles is on a line connecting the points A and B, and an angle formed by a cross section perpendicular to the axis of the screw blade is θ, and this θ is called a discharge angle. FIG. 5A is a developed view of the screw blade 101, in which the particle at the point A moves to the point B by one rotation of the screw blade, and its direction has an angle θ.

Then, assuming that AC is the outer peripheral length πD _b of one rotation of the screw blade, πD _b = ηt (cot α _b +
cot theta), from the relation of t = πD _b tanα _b, η is represented by a formula shown below, i.e., (9).

Η = tan θ / (tan θ + tan α _b ) In equation (8), when P _L is a positive value (> 0), the earth and sand discharging action is performed.

Here, the contents of the above equation (8) will be described.
Then, the first term (C ₁Term)
Is related to the rotation speed of the screw blade,
(C_Two Section) is for screw blades
Therefore, the third term is the shape of the screw blade, for example, the groove size.
(Pitch, depth, etc.) and the last section
(Sinφ term) relates to the weight of the soil in the cylindrical casing.
Things.

Therefore, in order to increase P _L in the equation (8), it is sufficient to make θ close to zero, which means that the rotation speed of the screw blade is increased from the relation of η.

By increasing the rotational speed of the screw blade, θ
If ≒ 0, the expression (8) becomes the following expression (10).

[0038]

(Equation 7) (10) from the equation, the first term in the right side {} (C ₁ has took term) is the only one that increases the P _L, the other terms,
It acts as a resistance when discharging earth and sand.

When earth and sand are used as a mass point (in a state where the inside of the cylindrical casing is not filled), the rotational speed of the screw blade can be obtained by balancing the centrifugal force of the mass point and the frictional force with the cylindrical casing.

As described above, when pressure (pushing force) is applied to the inlet (the earth and sand intake) of the cylindrical casing, the pressure acts over the entire length of the cylindrical casing. That is, the effect of providing the earth and sand pushing device effectively acts on the earth and sand transfer within the transfer cylindrical casing as the inlet pressure in the earth and sand transfer device.

[0041] For example, in (10), an outer diameter (D _b) of 700 mm, 260 mm shaft diameter (D _r) of the screw blade, 700 mm pitch of the screw blade (t), the thickness of the screw blade of the screw blade (E) is 25 mm, the length (L) of the cylindrical casing is 10 m, the inclination angle (φ) of the cylindrical casing is 45 degrees, and the shear stress (τ) is 10 mm.
When the pressure (P _L ) of earth and sand is calculated as gf / cm ^{2, the result is} as follows.

P _L = {+ 1.0693} -1.4142
= −0.345 kgf / cm ² , at least −0.345 kgf / cm ²
A pushing pressure of 45 kgf / cm ² or more is required. Therefore, in order to forcibly push the earth and sand taken into the earth and sand intake room into the earth and sand transfer device side using the earth and sand pushing device,
Even when excavating a hard ground such as a bedrock where no pressure acts on the sediment intake chamber, the sediment can be efficiently discharged.

In the first embodiment,
Although it has been described that the sediment intake chamber is formed by the partition part, the excavation is performed in a place where the pressure does not act on the sediment intake chamber, so the partition part may not be provided.

In the first embodiment,
Although the screw-type transfer device in the shield machine has been described, the present invention can also be applied to a screw-type transfer device in an open tunnel excavator in addition to the shield machine.

Next, a screw-type transfer device according to a second embodiment of the present invention will be described with reference to FIG. FIG.
As shown in FIG. 7, the screw-type transfer device 61 according to the second embodiment is for transferring granular materials from, for example, a low place to a high place, and is a transfer device for transferring the granular materials from below to above. 62, and a pushing device 63 for pushing the granular material into the transfer device 62 side.

The transfer device 62 includes a cylindrical transfer casing 71 having a particulate intake 71a formed at the lower end and a particulate outlet 71b formed at the rear end of the upper space. A transfer screw blade 72 having a shaft rotatably disposed in the transfer cylindrical casing 71, and a shaft of the transfer screw blade 72 also provided at the rear end of the transfer cylindrical casing 71. The part 72a is connected to a pair of gears 7
3, 74 and a first rotation drive unit (for example, a hydraulic motor, an electric motor or the like is used) 76 that rotates via a chain 75.

Further, the pushing device 63 is provided with an opening 81a at one end side at the intake 71a of the cylindrical transfer casing 71.
Is mounted in a substantially horizontal direction and has a hopper-shaped opening 81b at the other end, and a shaft-mounted pusher rotatably disposed in the pusher-shaped cylindrical casing 81. Screw blade 82 and a second rotation drive unit (for example, a hydraulic motor, an electric motor, or the like is used) 83 that rotates via a shaft 82a of the pushing screw blade 82. Note that 9
Reference numeral 1 denotes an unloading belt conveyor that is arranged on the discharge port 71b side of the transfer cylindrical casing 71 and that unloads the particulate matter to the outside.

According to the screw-type transfer device 61,
Similarly to the first embodiment, when the granular material is supplied from the hopper-shaped opening portion 81b into the pushing tubular casing 81, the granular material is transferred by the pushing screw blade 82 to the transfer tubular casing 81. Forcibly pushed into 71,
The granular material is efficiently transported from a low place to a high place by the transfer screw blade 72.

In the second embodiment, the screw blades 72, 82 disposed in the transfer tubular casing 71 and the push-in tubular casing 81 are provided with shafts. As in the case of the pushing screw blade in the first embodiment, a ribbon-shaped screw blade having no shaft portion can be used. Of course, in this case, it is rotated via an annular band provided on the outer peripheral portion of the ribbon-shaped screw blade. When the overall length of the transfer tubular casing 71 is long, that is, when the transfer distance (transfer vertical height) is large,
An annular band is provided on the outer periphery of the screw blade in the same manner as the ribbon-shaped screw blade rotation drive mechanism,
An auxiliary rotation driving unit for increasing the rotation driving force of the screw blade may be provided.

Furthermore, in each of the above embodiments, the interlocking mechanism between the screw blade and its rotary drive unit has been described as a direct connection with the drive unit and an interlocking mechanism with a sprocket and a chain. What you get. For example, an interlocking mechanism using gears can be used.

In each of the above embodiments, the case where the conveyed objects are earth and sand and granular materials has been described. However, for example, sludge materials, plastic materials (specifically, ready-mixed concrete, fermented moromi, etc.) Any object can be used as long as it can be conveyed by the screw blades.

[0052]

As described above, according to the structure of the present invention, since the object to be conveyed is forcibly pushed into the transfer device side by using the pushing device, no pressure acts on the intake space for the object to be conveyed. In such a case, that is, even when the pushing force does not act, the transported object can be efficiently transported.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a schematic configuration of a shield machine according to a first embodiment of the present invention.

FIG. 2 is a cross-sectional view showing a main part of a transfer device in the shield machine.

FIG. 3 is a view as seen from the direction of the arrow ii in FIG. 2;

FIG. 4 is an enlarged view of a main part of a screw blade for explaining a principle of obtaining a pressure in a cylindrical casing in the transfer device.

FIG. 5 is a diagram illustrating a relationship between a discharge efficiency and a discharge angle in the transport device.

FIG. 6 is a cross-sectional view illustrating a schematic configuration of a screw-type transfer device according to a second embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Shield excavator 2 Sediment taking-in room 3 Shield body 5 Cutter head 7 Screw-type conveying device 11 Sediment transfer device 12 Sediment pushing device 21 Transfer cylindrical casing 21a Sediment intake 22 Screw screw 23 for transfer 23 First rotation drive unit 31 Push-in tubular casing 32 Push-in screw blade 33 Second rotation drive unit 61 Screw-type transfer device 62 Transfer unit 63 Push-in device 71 Transfer tubular casing 71a Inlet 72 Transfer screw blade 76 First rotation drive unit 81 Push-in tubular casing 82 Push-in screw blade 83 Second rotation drive unit

Claims (1)

[Claims] 1. A screw-type transfer device for transferring an object to be transferred from a lower position to an upper position, wherein one end of the screw-type transfer device is located in an intake space of the object to be transferred and the object is transferred inside. Transfer device including a transfer cylindrical casing in which a transfer screw blade is disposed, and a first rotation drive unit for rotating the transfer screw blade, and an intake formed on one end side of the transfer cylindrical casing. A push-in tubular casing for pushing the transported object connected to the mouth, a pushing screw blade for pushing the transported object in the pushing tubular casing into the transfer tubular casing, and a pushing screw blade. A screw-type transfer device, comprising: a push-in device comprising a second rotation drive unit for rotating.