JPH0237346Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] This invention is used to bend a transport pipe from the tip of a boom at a high place, such as when pouring concrete using a concrete-placing pump truck equipped with a boom vehicle. The present invention aims to provide a bent hose for absorbing pulsating pressure in which a pulsating pressure absorbing hose is integrated with the end of the bent hose that hangs down.

[Conventional technology]

Hoses used for this type of application were previously
A hose of the same structure with high rigidity is used as a bending hose, but it has poor flexibility and poor directivity in the required vertical direction, and if the hose is forced in the vertical direction, the direction is corrected with a metal splint. However, in a previous application by the same applicant (Utility Model Publication No. 55-18624), a bending hose that did not require a metal splint was devised.
It is currently in effective use. This hose is a bent hose that is attached to the tip of the outlet of the transport pipe on the boom of a concrete placing pump with a boom vehicle, and the curvature of the hose changes in response to the movement of the position of the transport pipe or the change in elevation angle. It is constructed so that it can point in a fixed direction without giving way. Currently, when placing concrete on-site, a flexible general resin hose (7 m to 8 m) is attached to the tip of this bent hose. In other words, since the fresh concrete that is pumped into the bent hose by a pump causes large pulsations due to the pumping, a separate flexible resin hose is connected to alleviate the swinging of the hose at the discharge end, and the work is performed using pulsating pressure. At present, the work of pouring ready-mixed concrete is made easier by reducing the hindrances caused by the process.

[Problem that the invention attempts to solve]

Conventionally, the rubber hose attached to the tip of the extrusion outlet of the transport pipe on the boom was made of cloth to withstand deformation due to bending, as well as to withstand the weight of the resin hose attached to the end and the load of the ready-mixed concrete. A rubber hose that is sufficiently reinforced with metal wire and has little elongation exhibits good characteristics. For this reason, not only is the weight relatively large, but also the bending reaction force when bending the hose is usually large.

On the other hand, at the tip of the tip that discharges ready-mixed concrete, it is necessary to manually move and place the concrete in detail according to the conditions of the place where it is placed, so a light hose with low bending reaction force is required. If the pulsation caused by the pressure force of the concrete pump vehicle is not absorbed, the reaction of the discharge pressure during discharge placement will be transmitted to the human body, worsening work efficiency and causing problems in proper pouring.

Therefore, a general flexible resin hose has been connected to the hose near the discharge tip and used as a casting hose. In other words, two types of hoses, a rubber hose and a resin hose, are required for one installation. In addition, by connecting these lightweight resin hoses with low pressure resistance and high elongation to the tip of bent rubber hoses with low elongation, sudden changes in performance can cause discharge onto the inlet side (near the connection part) of the resin hose. A large amount of internal pressure load is applied, which, together with the weight of the discharged material over the entire length of the resin hose, causes premature wear and damage to the inlet side of the resin hose.

Furthermore, due to the difference in abrasion resistance between rubber hoses and resin hoses, even if the hoses initially have the same inner diameter, differences in the inner diameter occur due to the difference in the amount of wear during use, which is a cause of clogging of fresh concrete. Additionally, resin hoses generally have poorer wear resistance than rubber hoses, and must be replaced sooner than connected upper bent hoses.

As described above, the conventional connection structure between a bent hose and a resin hose causes the above-mentioned defects.

[Means for solving problems]

The inventors sought to solve the above-mentioned conventional defects by configuring a bent hose and a cast hose with pulsating pressure absorption characteristics into a single long hose. It is.

In other words, the bending hose attached to the tip of the pressure outlet of the transport pipe on the boom has an improved structure that is roughly similar to the bending hose in the previous application filed by the same applicant, and the added long part has flexibility. By improving the cord structure and high cord angle, the bend forming area (bending part) and the pulsating pressure absorption area (placing hose part) for placing ready-mixed concrete are connected to a single long hose (e.g. 5m~ 10m). Due to the necessity of this configuration, a complete direct crossing structure is not used for the wire clamping cord layer made of organic fiber reinforcing cords that directly contact the helical reinforcing wire vertically, and the cord angle is fixed in one direction. The cord angle is larger than the angle (54°45'). In other words, the cord angle selected from a high angle range of 66° to 80° is used to form wire clamping cord layers in the curved shape area and the pulsating pressure absorbing area of fresh concrete at the same cord angle, thereby reinforcing the pulsating pressure absorbing area. In order to effectively activate the spring property of the wire, the high angle of the cord of the wire clamping cord layer is configured so that it easily changes in the direction of the rest angle due to pressure,
The pulsating pressure absorbing property is sufficiently provided, and the bend forming area is configured to have a suitable bending support rigidity by suitable curvature and other reinforcing structures. The total length of the hose of this invention is
For example, if it is 5m, the rough guideline is about 1/5
is a highly rigid curved area, and the remaining approximately 3/5 is a pulsating pressure absorbing area for pouring, but this ratio is set appropriately depending on the usage situation.

The reinforcement formed on the inner surface rubber common to the bend forming area and the pulsating pressure absorption area is reinforced by forming wire rod holding cord layers above and below the reinforcing wire. , the cord direction is basically one ply with a high angle in one direction, and the basic one ply is set in opposite directions above and below the reinforcing wire, and in particular, the hose section in the pulsating pressure absorption area has a high degree of flexibility. The structure is such that the spring properties of the helical reinforcing wire are fully exhibited. In addition, if this wire rod clamping cord layer is too flexible depending on the usage conditions, and if it is necessary to adjust the flexibility to some extent, the wire rod clamping cord layer above and below the reinforcing wire rod may be A reinforcing cord layer having a density lower than that of the ply is added in a crosswise manner to the ply. In other words, in order to provide a high degree of bending flexibility in order to obtain a good bending condition when pouring fresh concrete,
This is not a complete intersection with equal density, but a unidirectional or slight intersection. However, if the cord angle is high in the upper limit direction, considerable flexibility can be obtained even if the degree of crossing is increased.

In addition, the curved area is formed so that the number of plies gradually increases from the pouring area side to the fresh concrete injection port side, and the cord angle gradually decreases from the inner layer ply side to the outer layer ply side. It consists of That is, in the reinforcing structure constructed on the inner rubber of the hose, in addition to the wire rod clamping cord layer common to the curved area and the pulsating pressure absorption area of fresh concrete, there is a wire rod clamping cord layer on the wire rod clamping cord layer in the normal curved area. , one ply of reinforcing cord layer is provided over the entire length of the curved area with a cord angle slightly smaller than the cord angle of the cord, and the reinforcing cord layer is gradually reduced in length and cord angle to the required ply level. However, the length and the number of plies of the gradually decreasing reinforcing cord layer on the full-length reinforcing cord layer at the bent portion are appropriately increased or decreased depending on the size of the hose and the conditions of use. In addition, the cord direction of each ply of the wire rod holding cord layer, the full length of the bent part, and the gradually decreasing reinforcing cord layer are arranged in opposite directions, and the full length of the bending part and the cord angle of the gradually decreasing reinforcing cord layer are set for each ply or Gradually decrease the angle every 2 plies.

In addition, the pitch of the spiral reinforcing wire that is set over the entire length of the curved shape area and the pulsating pressure absorption area is
It expands in several steps or sequentially from the injection port side at the base of the bend forming area toward the pulsating pressure absorption area, and within the pulsating pressure absorption area for pouring fresh concrete,
It is formed in a spiral shape over the entire length at equal intervals at the enlarged pitch. The cord angles of the full-length reinforcing cord layer and the gradually decreasing reinforcing cord layer are appropriately selected to be in a gradually decreasing state within the range of 65 degrees to 20 degrees.

[Effect]

As mentioned above, the bent area of the bent hose for absorbing pulsating pressure of this invention consists of a wire clamping cord layer with a large cord angle as a common reinforcing material for the entire length of the bent hose, a reinforcing cord layer for the entire length of the bent part, and a bent part on the outside thereof. Since it is composed of a gradually decreasing reinforcing cord layer whose length and angle are gradually decreased from the full length reinforcing cord layer, this gradually decreasing reinforcing cord layer has a large number of plies at the root, and the number of plies gradually decreases toward the tip. The shaped reinforcing wire has a pitch in the curved area,
Since the cord angle gradually increases from the injection port side at the base to the tip, it is not only possible to draw a smooth curve without sudden changes in curves, but also because the cord angle is gradually decreased with the inner side being at a high angle. ,
The wire rod clamping cord layer is not completely crossed in each ply layer, but only in one direction or slightly crossed, so it has a high degree of flexibility, does not buckle, has little change in inner diameter, and has gradual reinforcement. Coupled with the gradual decrease in the cord angle and the change in length of the cord layer, it is possible to maintain the load at the tip in a smooth curved state.

In addition, in the pulsating pressure absorbing area of fresh concrete, wire rod holding cord layers with a high cord angle in one direction or with a slight intersection are formed above and below the spiral wire rods at equal intervals at the expanding pitch of the spiral reinforcing wire rods. Because of this, it is easy to obtain a high degree of elasticity, and it has the ability to highly absorb the pulsating pressure caused by pumping fresh concrete.

That is, when pressurized, the hose performs elastic operation and easily moves in the resting angle (54°45') direction, and the internal volume increases as shown by the hose internal volume increase rate V% in the example shown in Fig. 4. , exhibits pulsation absorption performance.

〔Example〕

Next, aspects of the invention will be specifically described in detail based on illustrative drawings.

Figure 1 shows the bending hose of this invention for absorbing pulsating pressure.
A side view showing an example of a state diagram in which a BH is attached to the tip of a transport pipe on the high boom of a pump truck for pouring fresh concrete. The plan view shown in Figure 3 is
FIG. 3 is an enlarged plan view, partially in cross section, showing details of the bend forming area of FIG. 2;

This example is an example of a bent hose BH with an inner diameter of 89 mm and a length of 5000 mm. In this example, 1000 mm is the bent shape area that is formed into a bent state during use, and the remaining
4000mm is the pulsating pressure absorption area for the part where fresh concrete is placed, but this ratio is determined as appropriate depending on the usage conditions.

In the figure, PI is the injection inlet side of fresh concrete into the hose attached to the transport pipe TP, BS is the bend forming area, CSS is the pulsating pressure absorption area of the ready-mixed concrete in the characteristic classification for pouring the ready-mixed concrete, and DS is the discharge side that discharges fresh concrete.

1 is the base, 2 is a fixing ring for the reinforcing cord layer, this example uses a sagging polyester cord for the reinforcing cord layer, 3 is the inner rubber, and 4 is the lower wire clamping cord layer, which has a bending area BS and pulsation. pressure absorption area
The same state is set in both areas of CSS. In this example, one ply is formed with a cord angle of 70° in one direction. 5 is an intermediate rubber, 6 is a spiral reinforcing wire, and a hard steel wire with a diameter of 3 mm is used in the bending area of the hose.
In this example, between BS (between 1000mm), the pitch is gradually expanded from 8mm to 15mm, and in the pulsating pressure absorption area CSS of fresh concrete (between 1000mm and 5000mm), the pitch is expanded at equal intervals of 15mm in the front area. shall be. In this way, the spiral reinforcing wire rod 6 is set at equal pitches like a spring, and is held between the upper and lower sides by wire rod holding cord layers having a high cord angle. Reference numeral 7 designates an upper wire rod holding cord layer, which is set in contrast to the lower wire rod holding cord layer 4, and is formed at a cord angle of 70° for one ply with the cord direction being in the opposite direction.

As described above, the pulsating pressure absorption zone CSS for pouring fresh concrete consists of the inner rubber 3, the lower wire rod clamping cord layer 4, the spiral reinforcement wire 6 (pitch 15 mm) embedded in the intermediate rubber 5, and the outer cover. It is composed of rubber 15. The bend forming area BS has a reinforcing cord layer for the entire length of the bent part of the bend forming area BS, which has a cord angle smaller than the cord angle of the cord layer 7, on the outside of the upper wire rod clamping cord layer 7 that is common with the concrete pulsating pressure absorption area CSS. 8 will be provided. That is, in this example, the cord angle is 60 degrees, and the cord direction is set such that one ply in the opposite direction to the wire clamping cord layer 7 is the entire length of the bending area BS (1000 mm).

Next, the bending hose BH for absorbing pulsating pressure of this invention
A gradually decreasing reinforcing cord layer 9 from the PI end on the injection port side to a position of 900 mm is provided with one ply at a cord angle smaller than the cord angle of the full length reinforcing cord layer 8 at the bent part, and the cord direction is also opposite. In this example, the cord angle is set to 55°.

Next, similarly, the gradually decreasing reinforcing cord layer 10 of this example is set by gradually decreasing the cord angle and length.
800mm from the PI end and the cord angle
The angle shall be 50°. Similarly, the tapered reinforcing cord layer 11 is 700
mm, and the cord angle is 45°. Similarly, the tapering reinforcing cord layer 12 extends to a position of 600 mm, and the cord angle is 40°. Further, the gradually decreasing reinforcing cord layer 13 extends to a position of 500 mm, and the cord angle is 35 degrees.

Furthermore, a reinforcing cord layer 14 for fixing is applied to the base fixing part over a range before and after the inner end of the base.
Appropriately set 1 to 5 plies of the cord in close contact.

The entire outer periphery of the pulsating pressure absorbing bent hose BH provided with the reinforcing material as described above is covered with the outer cover rubber 15. The bent hose BH is an example in which the upper and lower wire rod holding cord layers 4 and 7 are folded back via the fixing ring 2 and firmly vulcanized and bonded to the base 1.

Figure 4 shows the pressure fluctuation state during extrusion transportation of fresh concrete using the bent hose BH for absorbing pulsating pressure, and shows the pulsating pressure state on the injection inlet side PI and the pulsating pressure state on the discharge side DS. The vertical axis is the fluctuating pressure P (Kg/cm ² ), the horizontal axis is the elapsed time t (sec.), the solid line is the PI fluctuating pressure at the injection inlet side PI, and the dotted line is the DS fluctuating pressure at the discharge side DS. This is what is shown.

As shown in the figure, the pulsating pressure absorbing bent hose BH of this invention exhibits excellent pulsating pressure absorbing characteristics.

Figure 5 shows the bent hose for absorbing pulsating pressure of this invention.
This is an example of a relationship diagram between BH pressure and hose internal volume increase rate, where the vertical axis is pressure P (Kg/cm ² ), the horizontal axis is hose internal volume increase rate V%, and the solid line is the curved shape. Hose internal volume increase rate V% at pressure inlet side PI of zone BS, dotted line is discharge side of pulsating pressure absorption zone CSS
This is the hose internal volume increase rate V% in DS.

[Effect of idea]

The bent hose for absorbing pulsating pressure of this invention has the above-mentioned operating characteristics because of the above-mentioned structure, and the bent shape area and the pulsating pressure absorbing area of fresh concrete are configured into one hose. This reduces the work time required for connection, eliminates the need for joint fittings, reduces weight, lowers manufacturing costs, increases durability, and greatly simplifies pouring of ready-mixed concrete on site. was gotten.

In addition, in the bend forming area, the cord angles of the wire rod clamping cord layers above and below the reinforcing wire rod are formed at a high angle,
It constitutes a common organic fiber cord reinforcement layer with the pulsating pressure absorption area of the ready-mixed concrete, and in the bending formation area, gradual reinforcement is configured in the direction of the outer layer, so stress is distributed appropriately against bending action and buckling does not occur. This provides rigidity that supports vertical directionality in a good curved state and flexibility in free directions.

Therefore, the pulsating pressure absorbing area that is continuous with the bend forming area allows easy pouring of fresh concrete without giving any resistance to the directional movement of the pulsating pressure absorbing area, and the pulsating pressure absorbing area has a good absorption characteristic of pulsating pressure. Due to the excellent configuration, the pouring work can be carried out smoothly without shaking the human body when working with the tip of the pipe on the discharge side during pouring of fresh concrete.

In addition, the pulsation absorption section, which absorbs pulsation pressure in fresh concrete, has a high cord angle and is flexible, so it has extremely flexible cushioning properties and wear resistance compared to ordinary rubber hoses. Then, a suitable fresh concrete pouring operation is performed.

As described above, this product contributes to improving practical value in the ready-mixed concrete pouring industry.

[Brief explanation of the drawing]

Figure 1 is a side view of a bent hose for absorbing pulsating pressure attached to the tip of a transport pipe at a high place, and Figure 2 is a part of the bent hose for absorbing pulsating pressure showing an example of implementation of this invention. Plan view showing cross-sectional structure, 3rd
The figure is an enlarged plan view showing the details of the bend forming area in Figure 2 with a partial cross section. Figure 4 is a diagram of the pulsation state of fresh concrete on the injection inlet side and discharge side. The solid line is the PI fluctuation on the injection inlet side. The curve and the dotted line are the discharge side DS fluctuation curve, the vertical axis is the fluctuating pressure P, the horizontal axis is the elapsed time t (sec.), and Figure 5 shows the relationship between the pressure on the injection inlet side and the discharge side and the rate of increase in the internal volume of the hose. In the curve diagram, the solid line is the pressure inlet side PI curve, the dotted line is the discharge side DS curve, the vertical axis is the pressure P, and the horizontal axis is the internal volume increase rate V% of the hose. BH...Bending hose for absorbing pulsating pressure, BS...Bending forming area, CSS... Pulsating pressure absorbing area, 3...Inner surface rubber, 4...Lower wire rod holding cord layer, 5...
Intermediate rubber, 6... Spiral reinforcing wire rod, 7... Upper wire rod clamping cord layer, 8... Full length reinforcing cord layer at bent portion, 9 to 13... Gradually decreasing reinforcing cord layer, 15...
Outer rubber.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) As a hose for force-feeding and pouring ready-mixed concrete, the above-mentioned hose has a bend forming area at a bent portion and a pulsating pressure absorbing area for pouring. As reinforcement across both areas, a wire clamping cord layer made of organic fiber cords that clamps the lower and upper parts of the spiral reinforcing wire buried in the intermediate rubber is provided on the inner rubber surface, and the reinforcing wire is placed in the bending area. Inside, the spiral pitch is expanded in several steps or sequentially from the injection port side, and within the pulsating pressure absorption area of the fresh concrete, the expanded pitch is set in a spiral shape with equal intervals, and a common area is used for both areas. The cord angle of the wire rod holding cord layer is 66°~
From the high angle range of 80°, select a required angle that is common to both areas above, and change the cord direction of the lower and upper wire rod clamping cord layers to one ply each in opposite directions or an auxiliary layer with a density coarser than that of this ply. The ply has cords added in a cross pattern, and in the bend forming area, a reinforcing cord layer for the entire length of the bend is set on the upper wire rod clamping cord layer at a cord angle smaller than the cord angle of the cord layer and in the opposite cord direction. , From this reinforcing cord layer toward the upper layer, the length of the reinforcing cord layer and the cord angle are sequentially gradually decreased, or two plies are applied and the gradually decreasing reinforcement cord layer is gradually decreased at the same angle, and the required plies are set in opposite cord directions, A bendable hose for absorbing pulsating pressure with both sections covered with a rubber outer layer. (2) Within the range of 65° to 20°, the cord angle of the full-length reinforcing cord layer and gradually decreasing reinforcing cord layer limited to the bending area is smaller than the cord angle of the wire clamping cord layer, and the cord angle is directed toward the upper layer. A bent hose for absorbing pulsating pressure according to claim 1 of the registered utility model claim, in which the cord angle is gradually reduced.