JPH0713434U - Rotary joint for large agitator - Google Patents

Abstract

(57) [Abstract] [Purpose] Improvement of rotary joint for large stirrer with hollow stirrer shaft. [Structure] An inner cavity extension cylinder 6 concentrically attached to the upper end of a hollow stirring shaft 2 and a cylindrical portion 7a fitted to the outer circumference of the inner cavity extension cylinder 6 below a connecting portion 8 for connecting to a fluid pumping section. 1
An outer cylinder body 7 which is appropriately fixed to a packing ring 10, a packing ring 10 inserted into the expanded diameter stepped portion at the lower end of the inner cavity of the cylinder portion 7a, and a packing retainer 11 having a pressing cylinder 11a for pressing the packing ring 10 from below, The packing retainer 11 provided between the flange 11b at the lower end of the packing retainer 11 and the flange 7b of the outer cylindrical body 7.
It is provided with a bolt nut 12 for pushing in.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an improvement in a rotary joint of a large-scale agitator that agitates a desired material to be agitated while pumping a fluid material such as a liquid or a gas body required for agitation into a hollow agitation shaft.

[0002]

[Prior art]

 Most agitators use a solid shaft as an agitation shaft, which is inexpensive and easy to manufacture. However, in some large-scale agitators, a hollow shaft is used as the agitation shaft, and the agitation must be performed while pumping the fluid through the hollow shaft. Conventionally, a commercially available general-purpose rotary joint has been used for such a large agitator.

In this general-purpose rotary joint, a required inner cylinder is attached to the upper end of the hollow stirring shaft in the stirrer so as to rotate together with the hollow stirring shaft, and is fixed to a required fixing portion so as to surround the inner cylinder. Attach the fixed outer cylinder so as to form a considerable space between it and the inner cylinder.In addition, at the center of the inner cylinder in the longitudinal direction, a hole for introducing fluid into the stirring shaft is provided. It is provided at several places around it, and a lateral passage that is orthogonal to the fluid introduction axis is attached to the outer cylinder at the central portion in the axial direction corresponding to the inner cylinder.

The end of the outer cylinder on the side opposite to the direction in which the hollow stirring shaft extends is closed, and mechanical seals and bearings are mounted between the outer cylinder and the inner cylinder at the upper and lower ends in the axial direction. , The inner cylinder is rotatably supported and the leakage of fluid is prevented.

Since the general-purpose rotary joint has such a structure, the fluid pumped in from the lateral direction enters the inside of the outer cylinder through the lateral passage, and passes through the hole provided in the inner cylinder from the space between the inner and outer cylinders. Flows in the rotating inner cylinder, turning downward.

[0006]

[Problems to be solved by the device]

 In the above-mentioned conventional technology, there are roughly two problems to be solved. One of them is that the pressure loss accompanying the fluid introduction is large. Pressurized fluid will flow into the inner cylinder from several holes provided in the inner cylinder, but the inner cylinder is rotating and the fluid flows against the centrifugal force, so the fluid pressure loss large. If the pressure of the fluid is increased to compensate for this pressure loss, the fluid will easily leak from the mechanical seals at the two upper and lower locations. Therefore, boosting is not preferable. Although it is possible to suppress the pressure loss to some extent by increasing the number and area of the holes provided in the inner cylinder, the number and size of the holes are naturally limited, and it is difficult to greatly suppress the pressure loss. Met.

Another problem is that this general-purpose rotary joint has a complicated structure and maintenance work is complicated. In particular, in order to inspect the mechanical seals and bearings, a complete disassembly is required, which is a troublesome work, and there is a problem that the operation must be stopped.

[0008]

[Means for Solving the Problems]

 According to the present invention, while feeding a fluid from the upper end of the hollow stirring shaft into the hollow stirring shaft, the hollow stirring shaft is rotated to stir the required object to be stirred by the stirring section at the lower end of the hollow stirring shaft. In a rotary joint that connects the hollow agitation shaft and the fluid pumping part of a large-scale agitator, the hollow extension shaft with the airtight connection of the lumen at the upper end of the hollow agitation shaft and the lumen of the cylinder part Is fitted to the outer periphery of the lumen extension shaft and is fixed to a required fixed portion, and a diameter-increasing step portion provided at the lower end of the lumen of the tubular portion and a fluid delivery portion provided at the upper end of the tubular portion. An outer cylindrical body each having a connecting portion to be connected to each other, and a diameter-expanding flange provided below the connecting portion, and a packing ring loaded in the diameter-increasing step portion of the cylindrical portion inner cavity of the outer cylindrical body. A tubular portion that fits into the enlarged diameter step portion of the tubular portion lumen in the outer tubular body, and is provided at one end of the tubular portion A packing retainer having an enlarged diameter flange for axially pressing the packing ring loaded in the enlarged diameter step portion, and the packing ring linked to the flange of the outer cylinder and the flange of the packing retainer. The problem described above is solved by providing a tightening screw that adjustably tightens in the axial direction.

[0009]

[Action]

 According to the present invention, the fluid to be pumped into the stirrer is passed from the top of the fixed outer cylinder of the rotary joint through the elbow that changes the direction in the same direction as the axis, or gently with a required curvature. , It is introduced straight along the axis of the rotating lumen extension cylinder and flows into the lumen of the hollow stirring shaft as it is. The movable part has only one sealing part on the outer circumference of the lumen extension axis, and the packing ring is tightened so that the sealing ability can be adjusted.

[0010]

【Example】

 FIG. 1 is a vertical cross-sectional view of a stirring shaft drive unit provided on the upper portion of a large-scale stirrer. A hollow stirring shaft (2) extends vertically in the housing body (1) of the stirring shaft drive unit. This hollow stirring shaft (2) is actually long, and extends long downward through the shock absorbing coupling (2a). Although not shown, in the stirring tank below, A stirring blade is attached to the lower end of the stirring shaft (2).

In addition, above the coupling (2a) of the stirring shaft (2), there are two upper and lower portions with a required space therebetween, and a pair of thrust radial bearings (3) are provided inside the housing body (1). It is rotatably and pivotally supported.

A gear (4) is attached to the stirring shaft (2), and the stirring shaft (2) includes a gear (4a) meshing with the gear (4), reduction gears (4b) (4c), and the like. It is decelerated to a required speed via and is rotated by the drive motor (5).

In the upper part of the housing main body (1) of FIG. 1, the stirring shaft (2) protruding upward from the upper bearing (3) protrudes outward from the housing main body (1), that is, the broken line The part surrounded by the circle (II) is the part of the rotary joint according to the present invention.

FIG. 2 is a central longitudinal sectional view showing an embodiment of this rotary joint. At the top of the hollow stirring shaft (2), a lumen extension cylinder (6) having a lumen (6a) having a diameter substantially equal to the inner diameter of the lumen (2b) of the stirring shaft (2) is concentric. The enlarged diameter flange (6b), which is arranged in a relation and is provided at the lower end of the lumen extension cylinder (6), is airtightly fixed to the top end surface (2c) of the stirring shaft (2) with a bolt (6c). . Therefore, the lumen extension cylinder (6) rotates together with the hollow stirring shaft (2).

A tubular portion (7a) of the outer tubular body (7) is fitted to the outer periphery of the lumen extending barrel (6) so as to rotatably support the lumen extending barrel (6). Is. The cylinder portion (7a) of the outer cylinder body (7) extends slightly above the upper end (6d) of the lumen extension cylinder (6), and above the cylinder portion (7a) there is a fluid not shown. A connecting part (8) for connecting the pumping part can be provided.

In a specific embodiment of the connecting portion (8), the flow path (8a) is bent at a right angle and is an elbow provided with flanges (8b) at both ends, and the flange (8b) at the lower end is an outer cylinder body. It is fixed to the upper end of the tubular part (7a) of (7) with a bolt (8c), and the tubular part (7a) and the connecting part (8) substantially form an integral structure and the outer tubular body (7). Is formed.

The lower end of the tubular portion (7a) of the outer tubular body (7) is a flange (7b) having an enlarged diameter, and the flange (7b) is a support member fixed to the housing body (1). It is firmly fixed to (9) with a bolt (9a). The support body (9) is formed in a tubular shape so as to surround the portion where the stirring shaft (2) projects from the upper end of the housing body (1), and the flange (9b) provided at the lower end is the housing body (1). It is fixed to the upper surface of the with bolts (9c).

With this structure, the lumen extension tube (6) rotates together with the stirring shaft (2), but the connecting portion (8) located above the lumen extension tube (6), that is, the elbow portion. Is fixed to the housing body (1) through the outer cylinder body (7) and the support body (9), and therefore does not move.

Therefore, the fluid flowing in from the fluid pumping part is substantially the same as the stirring shaft (2) from the elbow forming the connecting part (8) through the lumen extension cylinder (6) having the same inner diameter as the elbow. It has a cross-sectional area and is introduced without being affected by the centrifugal force due to the rotation of the stirring shaft (2).

An expanded diameter step (7c) is formed on the inner surface of the lower end of the tubular portion (7a) of the outer tubular body (7), and a plurality of packing rings (10) are inserted therein, and the packing rings (10) are inserted. The ring (10) is pressed by the packing retainer (11) from below. That is, the packing retainer (11) has an inner cavity that loosely fits the outer diameter of the inner lumen extension cylinder (6), and also loosely fits the expanded diameter step (7c) of the cylinder (7a). The push cylinder (11a) having an outer diameter is provided, and the expansion cylinder (11b) is provided at the lower end of the push cylinder (11a).

The packing presser (11) has a through hole (11c) provided in the flange (11b) of the packing presser and a through hole (7d) provided corresponding to the flange (7a) at the lower end of the outer tubular body (7). ) And bolt nuts (1 2) are inserted. The bolt and nut (12) can be tightened from outside the support (9). Therefore, the preload adjustment of the packing ring (10) can be easily performed without disassembling anywhere.

In the above embodiment, the outer tubular body (7) has the tubular portion (7a) and the connecting portion (8) formed separately, but the outer tubular body (7) has the tubular portion. (7a) and the connecting part (8) may have a non-separable integral structure. Further, the connecting portion (8) does not necessarily have to bend the flow path (8a) at a right angle like an elbow, and as another embodiment of the connecting portion (8), a stirring shaft (2 It is also possible to connect the fluid pumping section in a straight tube shape so as to be coaxial with the axis line of FIG.

[0023]

[Effect of device]

 The present invention has the following effects. (a) The fluid pressure loss into the large agitator can be significantly reduced. (b) The rotary joint of the present invention has a smaller number of parts than the conventional general-purpose rotary joint and can be manufactured at low cost. (c) Since there is only one movable seal part, the possibility of leaking fluid to be pumped is reduced. (d) Even if the seal packing wears, it is possible to adjust the seal preload by tightening the nut from the outside at any time without increasing the operation stop or disassembling, and easily increase the sealing effect. Of.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view of a stirring shaft driving unit of a large-sized stirrer having a rotary joint according to the present invention.

FIG. 2 is an enlarged vertical sectional view of a portion indicated by a chain line II in FIG.

[Explanation of symbols]

(1) Housing body (2) Stirrer shaft (2a) Coupling (2b) Lumen (2c) End face (3) Thrust
Radial bearing (4) Gear (4a) (4b) (4c) Gear (5) Motor (6) Lumen extension cylinder (6a) Lumen (6b) Expansion flange (6c) Bolt (6d) Upper end (7) Outside Cylindrical body (7a) Cylindrical part (7b) Flange (7c) Expanding step (7d) Through hole (8) Connecting part (8a) Flow path (8b) Flange (8c) Bolt (9) Support (9a) Bolt (9b) Flange (10) Packing ring (11) Packing retainer (11a) Push cylinder (11b) Flange (11c) Through hole (12) Bolt nut

Claims (4)

[Scope of utility model registration request] 1. A large-scale apparatus for rotating a hollow stirring shaft while feeding a fluid from the upper end of the hollow stirring shaft into the hollow stirring shaft to stir a desired object to be stirred in a stirring section at the lower end of the hollow stirring shaft. In a rotary joint that connects the hollow stirring shaft and the fluid pumping part of the stirrer, the hollow stirring shaft has an inner cavity extension shaft that is airtightly connected to the upper end of the hollow stirring shaft, and the inner cavity of the tubular part. It is fitted to the outer periphery of the cavity extension shaft and fixed to a required fixed portion, and is connected to a diameter expansion step portion provided at the lower end portion of the inner cavity of the tubular portion and a fluid delivery portion provided at the upper end of the tubular portion. And a packing ring loaded in the diameter-increasing step portion of the cylinder portion inner cavity of the outer tubular body, and the outer tubular body having the diameter-increasing flange provided below the coupling portion. A tubular part that fits into the enlarged diameter step part of the tubular part lumen;
A packing retainer which has an enlarged diameter flange provided at one end of the cylindrical portion and axially presses the packing ring loaded in the enlarged diameter stepped portion, and between the flange of the outer cylinder body and the flange of the packing retainer. A rotary joint for a large stirrer, comprising: a tightening screw that is linked to tighten the packing ring in an axially adjustable manner. 2. An outer cylinder body, wherein a cylinder portion having an inner cavity fitted to the outer periphery of the inner cavity extension cylinder and a coupling portion coupled to a fluid delivery portion at the upper end of the cylinder portion form a unitary structure. The rotary joint for a large stirrer according to claim 1, which is configured as follows. 3. The outer cylinder body comprises a cylinder part having an inner cavity fitted to the outer circumference of the inner cavity extension cylinder and a connecting part for connecting to the fluid delivery part at the upper end of the cylinder part, each being a separate body. The rotary joint for a large stirrer according to claim 1, wherein the rotary joint is connected to each other in an airtight manner. 4. The rotary joint for a large stirrer according to claim 3, wherein the connecting portion connected to the fluid delivery portion is an elbow having an axis of the lumen changed to a right angle and having flanges at both ends.