JPS6131190Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a suction switching device for a concrete pump that improves wear and tear on the cylinder side cap of the concrete pump.

FIG. 1 shows a side cross-sectional view of a suction section in a conventional concrete pump, and FIG. 2 shows a cross-sectional view taken along the - line in FIG.

Cylinder 1 that sucks in and discharges fresh concrete,
1' are arranged in parallel, and the fresh concrete in the hopper 2 is forced to be fed into the transfer pipe 4 through the swinging pipe 3 by repeating suction and pressure feeding using a piston (not shown).

The cylinders 1, 1' communicate with the hopper 2 at the bottom of the side of the hopper 2, and the cylinders 1, 1' and the transfer pipe 4 are connected by a swing pipe 3. Swing tube 3
slides on the side surface of the hopper 2 in conjunction with the suction and discharge of the cylinders 1 and 1'.
It communicates with the cylinders 1, 1' through the mouthpieces 5, 5', and continuously pumps fresh concrete.

Swinging of the swinging tube 3 is performed by applying hydraulic pressure to the arm 6 fixed to the swinging tube 3 by hydraulic cylinders 7, 7'.

In such a concrete suction/pressure feeding switching device, the mouthpieces 5, 5' at the mouths of the pair of concrete cylinders 1, 1' and the mouthpiece 8 at the swinging end of the swinging tube 3 are arranged so that they come into sliding contact in the fresh concrete atmosphere. It's getting old. With fresh concrete, both caps 5,
Both 5' and 8 wear out. In particular, as shown in Figure 3, which explains the shearing of stones in fresh concrete, stones in fresh concrete are sandwiched between both jaws 5, 5', and 8, and are sheared by the same jaws 5, 5', and 8. As a result, as shown in FIG. 4, portions a of the side caps 5 and 5' of the cylinders 1 and 1' wear out more than the other parts. FIG. 4 shows the wear profile of the side caps 5, 5' of the cylinders 1, 1' in FIG.
Because this part has more wear than other parts, fresh concrete flows out of the system through the gap c between cylinder 1, 1' side caps 5, 5', reducing the performance of the concrete pump, and It has the disadvantage that parts 5 and 5' must be replaced frequently.

Therefore, the object of the present invention is to provide a suction switching device for a concrete pump that prevents large local wear caused by stone shearing between the nozzles and reduces the frequency of replacement of the nozzles.

Embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 5 is a sectional side view of the main part of the suction switching device in the concrete pump according to the present invention.

Driven gears 10, 10' are attached to the outer periphery of the caps 9, 9' at the mouths of the cylinders 1, 1' which slide with the caps 8 at the tips of the swing tubes 3.

The gears 10 and 10' are covered by a casing 11, and the casing 11 covers the cylinders 1 and 10'.
1' and hopper 2. Also, a seal ring 12 is installed between the mouthpieces 9, 9' on the cylinder 1, 1' side and the hopper 2, and a seal ring 12 is installed between the mouthpieces 9, 9' on the cylinder 1, 1' side and the cylinders 1, 1'. A seal ring 13 is provided.

A plan view taken along the - line arrow in FIG. 5 is shown in FIG. 6.
The driven gears 10, 10' mesh with the drive gear 14, and the driven gears 10, 10' rotate in response to the rotation of the drive gear 14 (indicated by an arrow in the figure).

FIG. 7 shows a sectional view taken along the line -- in FIG. 6.
The drive gear 14 is driven by an electric motor (not shown) and is fixed to the wall of the hopper 2 via a bearing 15 and a bearing box 16. Reference numerals 17 and 18 are retainers for the bearing 15.

Lubrication of gear meshing parts and gear support bearing parts is mainly done by grease lubrication.

As shown in FIGS. 5 and 6, the driven gears 10 and 10' are driven by the driving gear 14, and the cylinders 1 and
By rotating the caps 9, 9' on the 1' side, the amount of wear on the sliding surfaces of the caps 9, 9' is equalized and reduced. If concrete enters the meshing portions of the gears 10, 10', 14, tooth surface wear progresses and smooth rotation cannot be maintained, so the seal rings 12, 13 play the role of preventing concrete from entering.

As described above, the sliding surfaces of the cylinder 1, 1' side caps 9, 9' are prevented from locally abrading and concrete flowing out of the system, and the above-mentioned caps 9, 9' are prevented from flowing out of the system.
The wear life of the caps 9, 9' is increased, and the frequency of replacement of the caps 9, 9' is reduced.

8 and 9 show a second embodiment of the present invention. In this embodiment, a combination of a worm gear 19 and a wheel gear 20 is used in place of the gear 10 which is the rotating means for the caps 9, 9' shown in FIG. 5 in the first embodiment. FIG. 9 is a view taken along the - line in FIG. 8, and shows wheel gears 20, 20 attached to two cylinders 1, 1' side caps 9, 9' by two worm gears 19, 19'. ′ is driven.

Almost the same effects as the first embodiment are achieved.

Note that in both the first and second embodiments, an example was shown in which one electric motor rotates the caps on the cylinder 1 and 1' sides, but the same result can be achieved even if two electric motors drive gears attached to the respective caps. Needless to say, effects can be obtained.

In short, according to the present invention, two cylinders that operate alternately are arranged side by side, and a switching mechanism is used to switch the swinging tube to the cylinder mouth side in the discharge process via the mouthpiece attached to the suction and discharge ports of the cylinders. In a concrete pump that alternately switches between the two cylinders, there is a drive that engages with the teeth of the two cylinder mouths and that is rotatably attached to the mouth of each of the two cylinders and that has teeth carved on the outer circumference of the cylinder. By having this means, the cylinder side mouthpiece is rotated periodically, and wear caused by stone shearing is dispersed over the entire circumference, thereby preventing local wear. Concrete does not leak out of the system from the sliding surface of the nozzle, ensuring concrete pump performance. Furthermore, by preventing local wear, the frequency of replacing the cap is reduced.

[Brief explanation of the drawing]

Fig. 1 is a side sectional view of the suction section of a conventional concrete pump, Fig. 2 is a sectional view taken along the line in Fig. 1, Fig. 3 is an explanatory diagram showing shearing of stones in the fresh concrete, and Fig. 4 is a sectional view taken along the line in Fig. 1. The figures are FIG. 3 - a sectional view taken along the line, FIG. 5 is a side sectional view of the main part showing an embodiment of the suction switching device in a concrete pump according to the present invention, and FIG. 6 is a plane taken along the line shown in FIG. 5. Figure, 7th
The figures are a cross-sectional view taken along the - line in FIG. 6, FIG. 8 is a side cross-sectional view of a main part showing a second embodiment of the present invention, and FIG. 9 is a view taken along the - line in FIG. 1, 1'... Concrete cylinder, 2... Hopper, 3... Swing pipe, 8... Base, 9, 9'...
Base, 10, 10'... Driven gear, 11... Casing, 12, 13... Seal ring, 14...
Drive gear, 15... Bearing, 16... Bearing box.

Claims (1)

[Scope of utility model registration request] In a concrete pump in which two cylinders that operate alternately are installed in parallel, and the swinging tube is alternately switched to the cylinder mouth side of the discharge process by a switching mechanism via a mouthpiece attached to the suction and discharge ports of the cylinders. , comprising a cap rotatably attached to each of the two cylinder mouths and having teeth carved on the outer circumference, and a driving means that engages with the teeth of the cap and drives the cap. Features a suction switching device for concrete pumps.