JPS6243956Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a rotary valve without a seal.

Multiple pockets are provided on the circumference of the rotor,
Rotary valves, which connect devices with a pressure difference and transfer powder or granular materials, are often used for supplying or discharging raw materials, for example, in the denaturation of proteins or starches under high pressure, or in the digestion of pulp.

However, in such a rotary valve, the high-pressure part and the low-pressure part are usually sealed with a gasket, and in principle there is a clearance 3 ( Generally, a seal 4 is installed on the rotor 1 or casing 2 to provide a seal between the high-pressure part and the low-pressure part.

However, a great deal of cost and time is spent on maintaining these packings 4, and improvements have been desired.

In view of this current situation, the inventor of the present invention changed his thinking and investigated various possibilities for rotary valves without seals, and found that it would be practical if the clearance 3 between the casing 2 and the rotor 1 was made extremely narrow (approximately 0.2 mm). It was found that sealing properties that can withstand heavy use can be obtained. However, with such a structure, iron powder generated from the rotor 1 or casing 2, or powder from the transferred raw material, accumulates and grows in the clearance 3, forming a layer, and the frictional force increases due to the so-called wedge effect, causing the rotor to 1
rotation will stop.

Therefore, as a result of repeated research and experiments, the inventor of the present application has found that by absorbing iron powder or raw material powder each time it occurs, it is possible to prevent its growth.
We believe that it is possible to operate rotary valves for long periods of time, and we use soft materials such as plastic materials (Teflon, Juracon, etc.) or soft metals (metallic, copper, aluminum, etc.) on the outer circumferential surface of the rotor or the inner circumferential surface of the casing. The present application was based on the knowledge that if the iron powder or raw material powder is buried and absorbed and held in them, the iron powder will not grow within the clearance and will not affect the rotation of the rotor in any way. Completed.

That is, the present application provides a rotary valve in which a rotor is rotatably supported inside a casing having a raw material supply port and a discharge port, and a recess is provided in at least one of the outer circumferential surface of the rotor and the inner circumferential surface of the casing, and the recess is provided in the recess. This rotary valve is characterized in that a soft member is embedded in the recess so that its surface is flush with the upper end surface of the recess.

First, in FIGS. 2 and 3, 11 is a casing of a rotary valve according to the present application, whose middle part is symmetrically bulged in a semicircular shape, both sides are covered with covers 12, and a horizontal cylindrical chamber is formed inside. form 13. At the top of the casing 11 is a raw material supply port 1.
4. Discharge ports 15 are provided at the bottom, and these are communicated with the chambers 13, respectively.

A rotor 16 is loosely fitted into the chamber 13 of the casing 11, and the rotor 16 is rotatably supported by a bearing 19 about a drive shaft 17 passing through the cover 12 of the casing 11.
The drive shaft 17 is driven by a motor or the like via a sprocket 18 fitted to its right end, and the bearing 19 is fitted into a bearing case 21 fixed to the cover 12 via a rib 20. .

23 is a gland packing provided on the drive shaft 17, which maintains a pressure difference with the outside.

On the other hand, in the radial direction of the rotor 16, a pair of raw material storage chambers 22 each having a cylindrical shape with a bottom are opened symmetrically and opened in the outer circumferential direction.
is configured to communicate with the supply port 14 and the discharge port 15 according to the rotation of the rotor 16.

In the rotary valve described above, the sealing means of the present application is configured as follows.

First, the clearance 24a between the rotor 16 and the casing 11 and the clearance 24b between the cover 12 of the casing 11 and the side surface 26 of the rotor 16 are made very small (about 0.1 mm to 0.2 mm) so that they almost slide into contact.

A rod-shaped soft member 25 is embedded in the outer peripheral surface of the rotor 16 so that its exposed surface is flush with the outer peripheral surface of the rotor 16 and coincides with the axial direction of the rotor 16. On the other hand, soft members 25 are similarly embedded radially in the side surface 26 of the rotor 16. At this time, due to the circumferential speed, the soft member 2 buried in the side surface 26
It is effective to form 5 in a fan shape.

With this configuration, as shown in FIG. 6, worn iron powder 29 peeled off from the inner surface 27 of the casing 11 or the outer circumferential surface 28 of the rotor 16 is removed from the soft member 25 buried in the rotor 16 whenever it occurs.
Since iron powder and the like are absorbed and retained in the clearance 24a, iron powder and the like no longer exist within the clearance 24a. Therefore, they do not accumulate in the clearance 24a, and the rotor 16 rotates smoothly for a long time.

Next, the embodiment shown in FIGS. 7 and 8 is an example in which the soft member 25 is formed into a small cylindrical block shape. Soft member 25 intermittently
may be embedded in the rotor 16. Here, it is effective to make the soft members 25 overlap with respect to the rotational direction of the rotor 16 and to embed them in both sides of the outer periphery and also in the outer periphery of the side surface, so that there are no gaps.

The embodiment shown in FIG. 9 is an example in which the cross section of the recess 30 in which the soft member 25 is buried is formed to widen toward the end, thereby making the soft member 25 more firmly fixed. In implementing this embodiment, the soft member 25 may be driven into the recess 30 and then cut.
Alternatively, it goes without saying that it may be fixed using screws.

Next, FIG. 10 shows an embodiment in which the rotor is formed into a tapered shape, and the overall configuration is similar to that of the second embodiment.
This embodiment is substantially the same as the embodiment shown in the figure, and the clearance 33 between the tapered rotor 31 and the casing 32 can be freely adjusted, and a means for adjusting the clearance is added.

The soft member 25 is installed only on the outer periphery of the tapered rotor 31, and the cover 34 of the casing 32 and the side surfaces 35 are arranged in order to adjust the clearance 33 between the tapered rotor 31 and the casing 32, as will be described later. It is omitted because it is not possible to provide a minute clearance between them.

In this embodiment, the adjustment of the clearance 33 is as follows:
If the sealing performance becomes poor due to the amount of clearance, the tapered rotor 31 is supported movably in the thrust direction by a needle bearing 36.
Attach the rotary joint 38 to the left end of the drive shaft 37.
This is done by tightening the adjustment bolt 39 provided through the .

In this embodiment, the clearance 33 due to wear of the casing 32 or the tapered rotor 31 is
It is easy to deal with the increase in

In this specification, an example in which the soft member is buried in the rotor has been described, but the same effect can be obtained even if the soft member is buried in the casing 2 as shown in FIG. 11 or in both the casing 11 and the rotor 16 as shown in FIG. Needless to say, this can be obtained.

As described above, the present invention can seal the high-pressure part and the low-pressure part by simply embedding the soft member in the rotor or casing, and since the rotor or casing and the soft member do not come into direct contact, It has the advantage that the amount of wear is extremely small compared to ordinary packing.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal sectional view of a conventional rotary valve, Fig. 2 is a front sectional view of the rotary valve of the present application, Fig. 3 is a view taken along line A-A in Fig. 2, and Fig. 4 is a longitudinal sectional view of a rotary valve of the present invention.
BB view of the figure, Figure 5 is a CC view of Figure 4,
Fig. 6 is an enlarged view of the D section in Fig. 3, Fig. 7 is a view of another embodiment, Fig. 8 is an E-E view of Fig. 7, and Fig. 9
Figures 1 to 12 show diagrams of other embodiments, respectively. In the drawings, 11 is a casing, 12 is a cover, 14 is a raw material supply port, 15 is a raw material discharge port, 16 is a rotor, 17 is a drive shaft, 22 is a raw material storage chamber, 24a and b are clearances, and 25 is a soft member. are shown respectively.

Claims (1)

[Scope of utility model registration request] In a rotary valve in which a rotor is rotatably supported inside a casing having a raw material supply port and a discharge port, a recess is provided in at least one of the outer peripheral surface of the rotor and the inner peripheral surface of the casing, and a soft member is inserted into the recess. A rotary valve characterized by being buried so that its surface is flush with the upper end surface of the recess.