JPH02306115A - Turbine type flowmeter - Google Patents

Abstract

PURPOSE:To adjust a gap between a bearing and a rotary shaft of an impeller to be a necessary one for rotating said impeller stably and smoothly by forming said bearing in the shape of a thin plate and holding said bearing in an axial direction of said rotary shaft in an elastically deformable manner. CONSTITUTION:The flow rate of a fluid running within a flow passage 2a is measured by magnetically detecting by use of a magnetic sensor 21 a magnet 22 of an impeller 11 rotating corresponding to the flow rate. Rods 5,9 of cones 3,7 upstream and downstream of the flow are fitted in central holes 4a,8a of supporting members 4,8, respectively, and therefore the position of the impeller in the axial direction can be adjusted by tightening nuts 6,10. Since pivot bearings 13,14 are elastically deformable like a leaf spring, even if end portions 12a,12b of a rotary shaft 12 are pressed against the bearing portions when a gap between the rotary shaft 12 and bearings 13,14 is adjusted, the bearings 13,14 themselves can deflect in the pressing direction within the range of their elasticity. Therefore, the rotary shaft 12 can be prevented from being broken.

Description

[Detailed Description of the Invention] Industrial Application Field The present invention relates to a turbine type 151 if, and in particular, it is configured to facilitate assembly and adjustment work while maintaining the integrity of the assembly when an impeller is assembled. Regarding turbine type flowmeter.

Conventional technology For example, in a turbine type 111 that measures the flow rate of a fluid such as city gas, pivot bearings made of gemstones such as artificial sapphire are provided on the upper and downstream cones, and the bearing part of the pivot bearing is used to measure the flow rate of a fluid to be treated. A device configured so that the rotating shaft is supported on the right at zero rotation is considered. In addition, in order to improve the flow #3 cutting performance, rji difference performance, and durability of the turbine-type flowmeter as described above, the rotating shaft of the impeller is connected to the bearing part by reducing the resistance □e. It is necessary to support the bearing smoothly and stably. Therefore, it has been proposed to provide the pivot bearing with a small hole that opens into the bearing, and to supply the flange fJ oil to the bearing through this small hole.

As a manufacturing method for such a bearing, for example, ■
A method of grinding and polishing a hemispherical concave part as a bearing part using gemstones such as sapphire or ceramics as wood, and then forming small holes by electric discharge machining or laser machining.
Alternatively, there may be a method in which a bearing portion is formed by grinding and polishing a hemispherical concave portion using a ceramic tube having n-holes as a material.

Problem A that the invention seeks to solve is that the manufacturing methods described in Items (1) and (2) above cannot be manufactured at a low cost because they use relatively expensive gemstones, such as diamonds, and the material used to make the pivot bearing is Naphire. Because it is made of high hardness 1α material such as Treasure G or ceramic, it can be ground and polished to create four hemispherical parts (bearing part).
There is a problem in that it takes one question to form a question.

Furthermore, in the upper two-turbine type 31, HIIFI
In order to improve accuracy, it is necessary that the impeller rotates smoothly from minute flow rates to 4 flows, and that the axis of rotation does not deviate. Therefore, in order for the blade to rotate even with a minute flow rate and to rotate smoothly even in the 1^^ flow rate range, the gap between the end of the rotating shaft in the blade and the bearing part of the pivot bearing must be as small as a few microliters. I4 must be adjusted to the correct value. That is, when assembling the impeller between the upstream cone and the downstream cone, the
Y! The clearance between the end of the rotary shaft and the bearing part of the pivot bearing is adjusted by shifting the position of the side bolt little by little in the axial direction. However, since the pivot bearing is made of highly hard wood such as jewelry or ceramic,
When the pivot bearing is pressed against both ends of the rotating shaft during the above adjustment, both ends are likely to break or deform. Therefore, in the conventional turbine-type flow control, not only is the above adjustment work tedious and time-consuming, but if the rotating shaft is damaged, the rotation of the impeller becomes unstable and the sub-side sensitivity decreases, and the rotational resistance increases. The problem arises that it is not possible to measure minute flow rates accurately and accurately.

Therefore, an object of the present invention is to provide a turbine-style language that solves the above problems.

Means for Solving the Problems The present invention provides the above turbine flowmeter in which the bearing is formed in a thin plate shape and is held so as to be elastically deformed in the axial direction of the rotating shaft of the impeller.

When assembling the working impeller, the bearing will elastically deform and damage the rotating shaft<r<, the gap between the bearing and the rotating shaft will be the minute gap necessary for the impeller to rotate stably and smoothly. , J, can be easily adjusted.

Embodiment II Figure 2 shows an embodiment of the Tanidon style mat according to the present invention. In FIG. 1, a flowmeter body 2 of a turbine type flowmeter 1 is arranged in the middle of a pipe through which a fluid to be measured such as gas is fed, with its axes aligned in the vertical direction. Note that the fluid is fed as indicated by arrows in the figure.

Reference numeral 3 denotes a cone on the flow side, and a rod 5 is inserted into the center hole 4a of the support member 4 inserted from below into the flow path 2a of the flow meter main body 2.
A nut 6 is screwed into the threaded portion 5a of the f1 screw 5.
It is fixed by tightening. Also, 7 is the downstream cone,
The rod 9 is passed through the center hole 8a of the support member 8 inserted from the -L direction into the flow path 2a, and tightened by a nut 1° screwed into the threaded portion 9a of the bolt 9.

An impeller 11 having a plurality of blades 111a on its outer periphery is interposed between the upstream cone 3 and the downstream cone 7. 12
is a rotating shaft of the blade middle 11, which is inserted into the hub center hole 11b. Note that both ends 12a and 12b of the rotating shaft 12 are formed into a conical shape.

Bearing holes 3a and 7'a of a predetermined depth are formed at the axes of the surfaces of the upstream steel cone 3 and the downstream steel cone 7 that face the impeller 11, and the bearing holes 3a.

7a is provided with a pivot bearing 13, 14 for bearing the rotating shaft 12 of the impeller 11, and a lubricating oil reservoir portion extending 15 degrees.

Note that the pivot bearings 13 and 14 and the oil reservoir 15 have the same configuration, so the upstream pivot bearing 13
The oil reservoir portion 15 will be explained with reference to FIG. 2, and the description of the downstream pivot bearing 14 and the oil reservoir portion 15 will be omitted.

In FIG. 2, the pivot bearing 13 is formed into a disk shape, for example, by a stainless steel metal plate for a spring, as will be described later. The pivot bearing 13 consists of a bearing part 13a on which the end part 12a of the rotating shaft 12 slides, and a flange part 13b outside the bearing part 13a. The bearing portion 13a is a hemispherical recess, and the! ! A rotating shaft 12 is supported at the center of one part.

The pivot bearing 13 is configured by bringing the outer periphery side flange 13b into contact with the step 3C provided in the opening of the bearing hole 3a [C provided in the first part 3b]. It is pressed and held by an annular holding member 17 provided at j53b. This holding member 17 is a bearing 1113 b
It comes into contact with the outer flange 13b. Therefore, the pivot bearing 13 whose peripheral edge portion is held in the bearing hole 3a by the presser member 17 is formed in the shape of a leaf spring and is held so as to be elastically deformable in the axial direction.

Therefore, when the axial push Fil jJ reaches nm, that is, when the rotary shaft 12 comes into contact with the pot bearing 13, the force is increased by 1 in the suppression direction.

Further, the pivot bearing 13 has a communication hole 13 formed along the axial direction and communicating the bearing tj513a and the oil reservoir part 15.
C is drilled in two places. This communication hole 13c is a small hole with an extremely small hole diameter, and one end is connected to the end 1 of the rotating shaft 12.
It opens at the center of the recess of the bearing part 13a that the bearing part 2a slides into,
The other end opens into the oil reservoir section 15.

The pivot shaft 13 can be easily produced by pressing technology. The manufacturing process is shown in FIGS. 3 and 4. That is, as shown in FIGS. 3(A) and (B), first,
A disk 13' is obtained by punching a thin metal plate (for example, stainless steel for a spring). Next, two small holes 13C' are bored near the center of the disc 13'. This small hole 13C'
The above-mentioned communication hole 13c is formed by, for example, etching.

According to this etching process, for example, a small hole 13C with a diameter of 0.05J11 is formed in a disk 13' having a thickness of 0.05°.
′ is effective. In addition to the above methods, methods for forming the small holes 13C' include methods such as -b, electric discharge machining, laser machining, and press machining.

Next, as shown in FIGS. 4A and 4B, the center portion of the disc 13' is drawn into a hemispherical shape to complete the bearing 13. Therefore, the pivot bearing 13 can be easily manufactured with fewer steps and at a lower cost than when it is manufactured from jewelry, ceramics, or the like.

Further, an oil storage body 18 is fitted into the inner part of the bearing hole 3a, and an oil reservoir chamber 19 in which lubricating oil is stored is formed between the oil storage body 18 and the pivot bearing 13.

That is, the oil reservoir portion 15 is connected to the oil storage body 18 and the oil reservoir chamber 19.
It becomes more.

The oil storage body 18 has a plurality of hollow portions 18a having a diameter larger than the communication hole 13c of the pivot bearing 13, and the hollow portions 18a are filled with lubricating oil.

Here, when the end portion 12a of the rotating shaft 12 comes into contact with the bearing portion 13a, the oil reservoir chamber 19 and the hollow portion 18a are filled!
? If) Oil is supplied little by little to the bearing portion 13a of the pivot E receiver 13 due to capillary action within the communication hole 13c.

11. As shown in FIG. 2, a bearing portion 13a.

The surface tension of the wax oil in the center of 14a and the hollow part 18a
A meniscus 20 of lubricating oil is formed with a size that balances the surface tension at the open end of the hollow portion 18a and the water head at the front end of the hollow portion 18a. Therefore, the pivot bearing 13 of the rotating shaft 12. “I
The sliding contact tttb''L with respect to n becomes extremely small, and the impeller 11 rotates smoothly and stably in accordance with the flow h1.
End portion 12a of rotating shaft 12.

12b and bearing parts 13a and 14a is reduced, and durability is improved.

Even if the lubricating oil in the bearings 13a and 14a evaporates and decreases, the lubricating oil is supplied in an appropriate amount due to the capillary action of the small curved communication holes 13c and 14G, so that the meniscus 20 of the lubrication trace
always maintains a predetermined size determined by the inner diameters of the communicating holes 13c and 14c and the inner diameter of the hollow portion 18a. Follow? Therefore, no slippage occurs on the bearing parts 13at-1l, and rr
JW1 oil is not supplied in excess.

Referring again to FIG. 1, a magnetic sensor 21 serving as a pickup is embedded in the upstream cone 3. A magnet 22 is attached to the rotor hub 11c so as to face the magnetic sensor 21. Therefore, the flow rate of the fluid flowing in the flow path 2a is determined by the magnetic sensor 21, which is detected by the magnet 22 of the impeller 11, which rotates in accordance with the outflow.
It is measured by detecting magnetically.

Here, the assembly process of the turbine flowmeter 1 having the above configuration will be explained.

As shown in FIG. 1, the turbine-type flowmeter 1 has the blade 11 supported in a rotation direction (r) between the upstream side 3 and the downstream side 7 as described above. When the impeller 11 is attached, first the upstream cone 3 is assembled (JIJ) from below the flow meter main body 2 into the flow path 2a via the support member 4. Next, the impeller 11 having one rotation shaft 12 is inserted into the flow path 2a from the end. It comes into contact with the portion 13a.

Thereafter, the downstream side tube 7 is inserted into the flow path 2a together with the support member 1 448, and the support member 8 is fitted into and held by the stepped portion 2C of the flow path 2. Note that the impeller 11 and the flow path 2 are connected so that the tips of the blades 11a of the impeller 11 do not come into contact with the inner wall of the flow path 2a.
A clearance is provided between a and a. Therefore, when assembling the impeller 11, the impeller 11 itself may tilt within the upper two clearances tJaRff12a.

However, the lower end 12 of the assembly rotation shaft 12
Since b is fitted into the L1 through hole 17a of the annularly formed presser member 17, it is fitted onto the inner wall of the through hole 17H and reliably abuts against the bearing portion 14 of the pivot bearing 14.

In addition, in the turbine flowmeter 1, in order for the impeller 11 to rotate even in a small flow rate range and to rotate smoothly without deviation even in a high flow rate range, the rotation shafts 12a, 12b and the bearing parts 13a, 14a must be connected to each other. Clearance is extremely important. This interval needs to be in a proper range of about 4 to 6 microns. However, in order to obtain this assembly accuracy, the entire length of the rotating shaft 12 must be processed accurately.

Pivot bearing 13.14 position, i.e. upper, downstream cone 3
．． Although it is necessary to control the spherical machining accuracy of the 7's n and the bearing parts 13a and 14a to sub-migration 0 or less, it is actually difficult to maintain high accuracy in the grain removal of these parts.

Therefore, in the assembly (1), the positions of the upper and downstream cones 3 and 7 are adjusted while flowing air as a test gas through the flow path 2a. That is, since the O-rads 5.9 of the upper and downstream cones 3 and 7 are fitted into the central holes 4a and 8a of the support member 4°8, respectively, the nuts 6.10 can be tightened depending on the axial position. is adjusted.

Here, if the pivot bearings 13, 14 are made of gemstones or ceramics as in the past, if the clearance between the rotating shaft 12 and the bearing parts 13a, 14b is adjusted below the appropriate level during the above adjustment, the rotating shaft 13. Both ends 12a, 12b of are pressed against bearings 13a, 14a.

In this case, conventional bearings have high hardness, and
Due to the strong force, both ends of the rotating shaft 12 were easily damaged.

However, in the present invention, since the pivot bearings 13 and 14 can be elastically deformed like leaf springs, when adjusting the gap between the rotating shaft 12 and the pivot bearings 13 and 14, both JWrA 12a and 12b of the rotating shaft 12 are Even when pressed by the pivot bearing 14a, the pivot bearing 13.14 itself can flex in the direction of the impact within its elastic range, and as a result, the rotation shaft 12
rupture is prevented. In addition, since the above adjustment work involves flowing air into the flow path 2a, the rotating shaft 12 is connected to the pivot bearing 13.
．． 14, the impeller 11 stops rotating, so both ends 12a, 12b of the rotating shaft 12 are connected to the bearing portion 13a,
It is easily determined that the contact point 14a has come into contact with the contact point 14a.

Therefore, after the rotation of the blades 1i11 stops, it becomes soil.

What is necessary is to shift either one of the upstream cones 3.7 in the separating direction and readjust it to a position where the impeller 11 rotates smoothly.

As a result, the gaps between the opposite ends 12a, 12b of the rotation @12 and the bearing parts 13a, 14a are adjusted to the minimum, and the impeller 11 can smoothly rotate four times from a small flow rate range to a high flow rate range.

Therefore, the adjustment work is easier and the navy blue IJ work process can be completed in a shorter time than when using conventional jewel or ceramic bearings.

In the above embodiment, spring stainless steel was used as the material for the pivot bearing, but the material is not limited to this, and other metal plates may be used as long as they have the elasticity and strength necessary to support the rotation shaft of the impeller. You may also use

Effects of the Invention As mentioned above, the turbine flow according to the present invention! t) According to BH, since the pivot bearing is elastically deformable in the axial direction,
During the first stage of assembly, it is possible to prevent M4 damage when the end of the rotating shaft comes into contact with the bearing, and the gap between both ends of the rotating shaft and the bearing of the pivot bearing can be minimized within the blade. From the flow rate range to the high flow rate range, it can be easily adjusted to the minimum suitable level required for safe and smooth rotation. Therefore, ii'l measurement sensitivity total sensitivity μ, flow rate measurement 1[ti Furthermore, since pivot bearings can be easily manufactured from thin metal plates, they can be processed more easily and with less effort than conventional pivot bearings, making them an excellent product that reduces manufacturing costs. Highlight the features of

[Brief explanation of the drawing]

Figure 1 shows one example of the turbine type flow ttV+ according to the present invention t^
Example longitudinal sectional view, Figure 2 t shows the main parts of main stand 11 +11J
3 (A>, (8)) and FIG. 4 (A>, (B)) are process diagrams for explaining the steps in manufacturing the pivot bearing. 1.・・Turbine type flow fE1 it, 2・・・Flow n; Planning tree rest body 2a・・Flow path, 3・・Upstream cone, 7・・・
・Downstream cone, 11... Impeller, 12... Rotating shaft, 13.14...-Pivot bearing, 13a, l4a--
- Bearing part, 13b. 14b... Flange portion, 13G, 14G... Small hole, 15° angle... Oil sump portion, 17... Holding member, 18... Hollow oil body, 19... Oil sump narrow. Patent Applicant Toki” Patent Attorney Kanetr Matsuura
, ', ', ``, '. 'm1.i-Niri Fig. 1 Turbine flow meter Fig. 2 Rotating shaft

Claims (1)

[Claims] It has an impeller that rotates according to the flow rate of the fluid to be measured, a rotating shaft that rotates together with the impeller, and a bearing that supports the rotating shaft by sliding an end of the rotating shaft on one side. A turbine flowmeter characterized in that the bearing is formed in a thin plate shape and is held so as to be elastically deformable in the axial direction of the rotating shaft.