JP3953236B2 - Squeezing concrete pump - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a squeeze-type concrete pump, and more particularly to a squeeze-type concrete pump using a pumping tube whose thickness is gradually increased toward the discharge side.
[0002]
[Prior art]
Generally, a squeeze-type concrete pump is equipped with an elastic pumping tube in a horizontal U-shape in a cylindrical casing, and rolls while pressing the roller supported by the rotor along the pumping tube. The pressing action and the restoring action of the pumping tube itself give a pumping action to the pumping tube to pump the ready-mixed concrete sucked into the pumping tube.
[0003]
However, when the roller begins to release the pressure of the pumping tube on the discharge side of the pumping tube and the inside of the pumping tube begins to open, the pressure difference between the front and rear of the roller (the front side is higher than the rear side of the roller) Ready-mixed concrete flows backward due to high pressure due to long-distance placement. For this reason, the inner surface of the pumping tube is particularly severely worn at the position where the roller releases the pressure of the pumping tube, causing the life of the pumping tube to be shortened.
[0004]
Therefore, in order to reduce the back flow of the ready-mixed concrete as much as possible and to prolong the life of the pumping tube, as disclosed in Japanese Patent Application Laid-Open No. 59-3189, the pumping tube is made to the suction side opening area. It is considered that the opening area on the discharge side is tapered so as to extend over substantially the entire length. According to this tapered pumping tube, the sealed chamber in the pumping tube that is temporarily confined by the upper and lower rollers is gradually pressurized with a slight difference in the area of the front and rear in the pumping tube due to slight movement of the rollers. Therefore, even if the pressing of the pumping tube is released, the back flow of the ready-mixed concrete can be reduced.
[0005]
[Problems to be solved by the invention]
However, in the above structure, the thickness of the pressing start position of the pumping tube by the roller and the thickness of the pressing release position are significantly different. Therefore, it is necessary to decenter the center position of the rotor with respect to the center position of the casing. Therefore, the support member for the rotor must be provided at a position slightly deviated from the center position of the casing, which is a large component, and the manufacture of the casing becomes complicated and a special jig is required.
In addition, a casing using a taper-shaped pumping tube and a casing using a straight pumping tube having the same wall thickness and inner and outer diameter over the entire length differ in the mounting position of the rotor with respect to the casing. Cannot be combined. For this reason, a dedicated casing must be manufactured according to the type of pumping tube to be used, which increases the number of parts and makes the manufacturing more complicated.
SUMMARY OF THE INVENTION An object of the present invention is to provide a squeeze-type concrete pump that can be directly applied to a taper-shaped pumping tube using a casing that can be easily used for a straight pumping tube.
[0006]
[Means for Solving the Problems]
In order to achieve the above object, a squeeze-type concrete pump according to the present invention comprises a pumping tube provided along an inner wall of a cylindrical casing, and a roller supported by the rotor and pressing the pumping tube from the inner peripheral side in the casing. In the squeeze-type concrete pump that applies the pumping action by the pressing action by the roller and the restoring action of the pumping tube itself, sucks the ready- mixed concrete into the pumping tube, and pumps the sucked ready-mixed concrete. An elastic pad is interposed between the inner wall and the pumping tube so that the outer diameter of the pumping tube is substantially the same, the inner diameter is gradually reduced toward the discharge side, and the wall thickness of the pad is reduced to the discharge side. The pad is gradually reduced toward the Over the entire length, the sum of twice the thickness of the pad Metropolitan thick pumping tube as substantially the same, characterized in that substantially aligned with the center of the casing and the rotor. According to the squeeze-type concrete pump having the above-described configuration, the rotor can be disposed at the center position of the casing despite the use of the tapered pumping tube.
[0007]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a sectional view showing the entire squeezed concrete pump of the present invention, and FIG. 2 is a sectional view of a pumping tube.
A squeeze-type concrete pump 1 that pumps ready-mixed concrete includes an elastic pumping tube 3 inserted into a cylindrical casing 2 in a horizontal U shape as shown in FIG. It protrudes from the opening 4. A rotor 6 is provided in the center of the casing 2, and the center of the rotor 6 is attached to the casing 2 via the rotating shaft 5 and the support members 20 and 21 (see FIG. 4). The rotating shaft 5 is connected to a hydraulic motor (not shown). Two rollers 7 are pivotally supported at the end of the rotor 6 with a phase shifted by 180 degrees.
[0008]
The roller 7 presses the pumping tube 3 from the inner peripheral side in the casing 2, and when the rotor 6 rotates in the clockwise direction (arrow Z direction in FIG. 1), the roller 7 rotates at 6 o'clock in FIG. The pressing of the pumping tube 3 starts from the position, rolls along the pumping tube 3 as it is, releases the pressing at the 12 o'clock position of the timepiece, and moves away from the pumping tube 3. Thereby, the ready-mixed concrete sucked from the lower end of the pumping tube 3 by the restoring force of the pumping tube 3 itself is pumped from the upper end of the pumping tube 3. A pair of left and right guide rollers 8 are attached to the rotor 6, and the guide rollers 25 regulate the meandering of the pumping tube 3. A restricting member 9 is pivotally supported on the rotor 6, and the restricting member 9 restricts the pumping tube 3 from being separated from the casing 2 due to the roller 7 being pressed and rolled.
[0009]
As shown in FIG. 2, the pumping tube 3 has an outer diameter D that is substantially the same over the entire length, and an inner diameter that gradually decreases from the suction side toward the discharge side. That is, the opening area of the inner diameter D22 on the discharge side is smaller than the opening area of the inner diameter D12 on the suction side.
Further, since the pumping tube 3 is somewhat compressed at the pressing release position of the roller 7, even if the roller 7 moves somewhat clockwise from the 12 o'clock position, the pumping tube 3 The closed state is maintained. For this reason, the pressure in the sealed chamber 10 of the pumping tube 3 confined by the two rollers 7 is pressurized by the slight movement of the roller 7 in the clockwise direction.
[0010]
An elastic pad 11 is provided between the inner wall of the casing 2 and the pumping tube 3, and left and right flanges 12 of the pad 11 are fixed to the casing 2 by a stopper member 13 (see FIGS. 5 and 5). (See FIG. 6). The pad 11 is included in ready-mixed concrete in the pumping tube 3 while reducing the frictional resistance with the casing 2 when the pumping tube 3 moves somewhat back and forth by being pressed and rolled by the roller 7. It plays the role of absorbing the deformation of the pumping tube 3 when the pebbles are sandwiched.
[0011]
The pad 11 is gradually reduced in thickness from the suction side to the discharge side, and is pumped from the total D11 and D21 of the outer diameter D of the pumping tube 3 and the thickness of the pad 11 over the entire length thereof. The numerical value obtained by subtracting the inner diameters D12 and D22 of the tube 3, that is, the total thickness D1 and D2 (see FIG. 3) of twice the thickness of the pumping tube 3 and the thickness of the pad 11 is set to be substantially equal. Thereby, the space | interval of the roller 7 and the casing 2 inner wall can be made substantially the same, and the rotating shaft 5 of the rotor 6 can be made to correspond with the center of the casing 2. FIG.
[0012]
Next, the operation of the concrete pump 1 having the above configuration will be described. First, when the rotor 6 is rotated in the arrow Z direction by the hydraulic motor from the state of FIG. 1, the lower roller 7 rolls upward while pressing the pumping tube 3, and the upper roller 7 moves away from the pumping tube 3 and moves downward. Move to. As a result, the pumping tube 3 behind the lower roller 7 sucks the ready-mixed concrete by returning to the original circular shape by the restoring force of the pumping tube 3 itself, and the ready-mixed concrete in the pumping tube 3 ahead of the lower roller 7. Is pumped forward. At that time, since the inner diameter of the pumping tube 3 is tapered, when the roller 7 is slightly rotated from the position of FIG. 1 in the direction of the arrow Z, the sealed chamber 10 of the pumping tube 3 configured between the pair of rollers 7 is formed. When the pumping tube 3 is opened by releasing the pressure of the roller 7 in this state, the difference between the pressure in the sealed chamber 10 and the pressure in front of it is reduced. For this reason, the back flow of the ready-mixed concrete can be reduced, and the wear on the inner surface of the pumping tube 3 can be reduced.
[0013]
Further, when the upper roller 7 moves downward and presses the suction side of the pumping tube 3, even if the pebbles contained in the ready-mixed concrete are sandwiched in the pumping tube 3, the deformation is not achieved by the pumping tube 3 alone. Although it cannot be absorbed because it is thin, it can be absorbed sufficiently by the thickness of the pad 11, and damage to the inner surface of the pumping tube 3 can be prevented.
Further, since the center of the rotor 6 coincides with the center of the casing 3, when the casing 2 is manufactured, the support members 20 and 21 of the rotor 6 may be disposed at the center of the casing 3. Is very easy. In addition, a casing using a pumping tube having a straight wall thickness and inner / outer diameter can be used as it is.
[0014]
【The invention's effect】
As described above, according to the present invention, since the center of the rotor can be made coincident with the center of the casing, the casing can be easily manufactured. In addition, despite the use of a tapered pumping tube, a casing using a straight pumping tube with a straight wall thickness and inner / outer diameter can be used as it is, so the number of parts can be reduced. .
Furthermore, although the thickness of the pumping tube is thin at the position where the pumping tube is pressed by the roller, the thickness of the pad at the pressing start position is thick. Even when the included pebbles are sandwiched, deformation of the pumping tube due to the pebbles can be sufficiently absorbed by the pad, and damage to the inner surface of the pumping tube can be prevented.
[Brief description of the drawings]
FIG. 1 is an overall sectional view of a squeezed concrete pump of the present invention.
FIG. 2 is an overall sectional view of a pumping tube.
FIG. 3 is an enlarged view of a main part of the pumping tube.
4 is a cross-sectional view taken along line A-O-A in FIG.
5 is a cross-sectional view taken along line VV in FIG.
6 is a cross-sectional view taken along line VI-VI in FIG.
[Explanation of symbols]
1 Squeezed concrete pump 2 Casing 3 Pumping tube 6 Rotor 7 Roller 11 Pad

Claims (1)

A pumping tube which is provided along the inner wall of the cylindrical casing, and a roller for pressing the pumping tube from the inner circumferential side in and the casing is supported by the rotor, the pressing action and the pumping tube itself due supported roller to the rotor In the squeeze-type concrete pump that gives the pump action by the restoring action of and sucks ready-mixed concrete into the pumping tube and pumps the sucked ready-mixed concrete,
An elastic pad is interposed between the inner wall of the cylindrical casing and the pumping tube so that the outer diameter of the pumping tube is substantially the same and the inner diameter is gradually reduced toward the discharge side. While gradually reducing the wall thickness toward the discharge side, the center of the casing and the rotor is set so that the total of the wall thickness of the pad and the thickness of the pumping tube is approximately the same over the entire length of the pad. A squeeze-type concrete pump characterized by being substantially matched.

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