JPS6234260Y2 - - Google Patents

Description

[Detailed description of the invention] This invention uses an axial flow impeller that is rotatable around the center line of the pipe and is rotationally driven by the flow inside the pipe to drive an integrating device located outside the pipe. This invention relates to a so-called axial flow impeller type water meter.

In this type of water meter, in order to transmit the rotation of the axial flow impeller to the integrating device, a worm is fixed to the rotating shaft of the axial flow impeller, and a worm wheel that meshes with the worm wheel is installed to transmit the rotation to the transmission shaft. However, in this case, the worm wheel or the box that protects it will be in a position that obstructs the flow inside the pipe, which is undesirable. On the other hand, there are some gears that guide the gear out of the pipeline using a radial transmission shaft, but bevel gears are generally expensive, do not necessarily have good transmission efficiency, and have problems with durability. Furthermore, in the conventional example described above, it is necessary for the transmission shaft to pass through the shaft sealing device, and there is also a drawback that friction in that portion impairs measurement accuracy.

Furthermore, as shown in U.S. Pat. No. 3,169,398, rotation transmission by magnetic coupling has conventionally been used.
In this system, an axial flow impeller is fixed to a rotating shaft, a bevel gear-shaped main magnet is fixed to the rotating shaft downstream of the axial impeller, and the power is transmitted to the main magnet on an axis perpendicular to the rotating shaft. A driven magnet in the shape of a bevel gear is arranged so that the driven magnet rotates to drive the integrating device, but the structure for supporting the rotary shaft rotatably and immovably in the axial direction is complicated. However, when screwing the axial flow impeller to the rotating shaft to fix it, it is difficult to hold the rotating shaft in a non-rotatable manner, and it is expensive.

The purpose of this invention is to eliminate such drawbacks, and as shown in the embodiment shown in the figure, a fixing member 2' that protrudes toward the center from the outer wall of the pipe 1 having a circular cross section is inserted into the pipe 1. A supporting base 2 is provided, and an internal space 2a is provided in the supporting base 2, which is isolated from the inside of the conduit 1 and communicated with the outside. N along the direction of rotation,
It has both S magnetic poles alternately, and the inside of the conduit 1 and the support base 2.
A driven magnet 6 is arranged so that the magnetic force is transmitted to the main magnet 5 through a partition wall 2b between the inner space 2a of the pipe 1 and the inner space 2a of the pipe 1.
This is an axial flow impeller type water meter that drives a totalizing device 7 installed outside of the water meter. A shaft 3 is provided, and a support portion 3a that supports the downstream thrust of the impeller is formed at the tip of the fixed support shaft 3. A fitting hole is formed to hold the main drive magnet 5 having both magnetic poles alternately, and the fixed support shaft 3 is fitted into the hole, a receiving part for the supporting part is provided at the bottom of the hole, and the axial flow impeller is fixed to the fixed support shaft. 3 so that the main magnet corresponds to the driven magnet 6 on the integrating device side.

In this embodiment, the main magnet 5 and the driven magnet 6
Both have a total of four poles, two N poles and two S poles, and the main magnet 5 has a pole on the outer periphery of the cylindrical surface, and the driven magnet 6 has a pole near the outer diameter of the side surface of the disc surface.

According to this invention, an internal space 2a that is isolated from the pipe section and communicated with the outside is provided in the support base 2 fixed in the pipe line 1, and a driven magnet 6 is provided in the inner space 2a. Therefore, the rotating shaft of the driven magnet 6 does not require a shaft sealing device for watertightness. Therefore, there is no friction or the like that adversely affects instrumental error. Further, an immovable fixed support shaft 3 is immovably provided on the support base 2 along the center line of the pipe, a support portion 3a is provided at the tip of the fixed support shaft, and an axial flow impeller equipped with a main drive magnet 5 is installed. 4 is fitted into the fixed support shaft through a fitting hole provided therein, and is directed toward the downstream side of the axial flow impeller by engaging with a received portion provided at the bottom of the fitting hole of the supporting portion 3a. Since the thrust force is supported, the attachment of the axial impeller 4 to the support shaft is simply by fitting the fitting hole into the fixed support shaft, which has the advantage of being significantly simpler than the conventional device. Moreover, the structure is simple and assembly work is easy.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of one embodiment of this invention. 2... Support base, 3... Fixed support shaft, 3a... Support part, 4... Axial flow impeller, 5... Main drive magnet, 6...
Driven magnet, 7...Integrator.

Claims (1)

[Scope of utility model registration request] When driving the integration device installed outside the pipeline by the rotation of the axial impeller 4 installed inside the pipeline, a magnetic force is transmitted between the drive system on the integration device side and the drive system on the axial impeller side. In the case where a means is interposed, a support base 2 is installed in the pipe via a fixing member, and the support base 2 is isolated from the inside of the pipe and communicates with the outside through the fixing member. A fixed support shaft 3 having a support portion 3a supporting the downstream thrust of the axial flow impeller at its tip is fixedly planted on the support base 2 along the center line of the pipe to make it immovable. The axial impeller 4 is provided with an insertion hole that directly supports the driving magnet 5 and into which the fixed support shaft 3 is inserted, and a receiving part for the support part 3a is formed at the bottom of the hole. The axial impeller is rotatably and removably fitted to the support shaft 3, and a driven magnet 6 facing the main drive magnet 5 is provided in the inner space 2a of the support base. An axial flow impeller type water meter characterized in that the transmission means uses the magnetic force.