JPS6338397Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] This invention relates to the mounting structure between a pump impeller and a pump shaft, and in particular, the removable mounting of an impeller and its drive shaft in a pump using a screw blade. This relates to structural improvements.

[Prior art]

FIG. 5 shows a mounting structure of this type that has been commonly adopted in pump configurations, in which an impeller and its drive shaft can be freely attached and detached in a screw vane pump.

That is, in each of these figures, numeral 1 is a main body housing, 2 is a pump casing which forms a pump chamber 3 inside and is provided in the housing 1, and 4 is a suction cover. Further, 5 is a drive shaft with a shaft end 5a protruding into the pump chamber 3 via a gland packing and a water seal 6 between it and the housing 1, and 7 is a drive shaft that is keyed to the drive shaft 5. A hub member 9 is fitted and fixed to the shaft end 5a by screwing a locking nut 8, and is fitted to the hub member 7 in the pump chamber 3 and is fixed to the shaft end 5a of the drive shaft 5. This is an impeller with screw blades 10 attached.

In the case of the above configuration, the details of the attachment and connection of the impeller 9 to the drive shaft 5 are as follows. That is, with respect to the flange portion 7a of the hub member 7,
The base side of the impeller 9 is closely fitted and held by a spigot structure, and rotation is prevented by a pin 12. On the other hand, a mounting hole 11 is drilled through the head of the impeller 9 in the axial direction of the drive shaft 5, and a hexagonal socket bolt 13 is inserted through the mounting hole 11 into the shaft end 5a of the drive shaft 5. By screwing together the impeller 9, the impeller 9 is connected to the drive shaft 5 via this hexagon socket head bolt 13.
is attached and fixed. In addition, hexagon socket head bolt 13
A cap member 14 made of corrosion-resistant rubber or the like is fitted into the opening of the mounting hole 11 through which the cap member 14 is inserted.

[Problem that the invention attempts to solve]

In a general pump configuration, when adapted to the conventional configuration, in order to improve the foreign matter passage at the inlet of the screw blade 10, that is, at the head, which is the center of rotation of the impeller 9, the following steps are required: It is desirable to place the base 10a of the screw blade 10 as close to the center of the head as possible, but in the case of the conventional structure, the mounting hole 10 is located at the center of the head.
Form an opening in 1 and insert hexagon socket head bolt 1 from here.
3, so the screw blade 1
The position of the base 10a of the bolt 13 must be set outside the outer diameter of the head 13a of the bolt 13, so that the front surface of the head 13a of the bolt 13 and the front surface of the head of the impeller 9 are There is a risk of foreign matter getting caught in the ridge corner, and the shape of the flow path in the same part also lacks smoothness.Furthermore, it is difficult to fit the base side of the impeller 9 into the flange part 7a of the hub member 7 with a spigot. However, attaching and detaching this pilot fitting is quite troublesome, and when there is no means for attaching and detaching as in the conventional configuration, the attaching and detaching operation requires skill and is extremely time-consuming. There was a drawback that it was.

Therefore, the purpose of this invention is to provide an improved pump that can smooth the impeller shape and, ultimately, the flow path shape without impairing it as much as possible, and also allows easy attachment and detachment of the spigot fitting. An object of the present invention is to provide a mounting structure for an impeller and a pump shaft.

[Means for solving problems]

In order to achieve the above object, this invention supports a hub member on the pump drive shaft, prevents the base side of the pump impeller from rotating on the hub member, and engages the hub member with a spigot.
A holding recess is formed in the center of the impeller from the base side, and the head of a hexagon socket head bolt is fitted into the holding recess with a margin in the tightening direction, and the head is screwed into the holding recess. The annular locking nut holds the head of the hexagon socket head bolt from the base side of the impeller so that it can only be rotated forward and backward, and the bolt is rotated from the outside into the holding recess at the center of the tip of the impeller. By forming an insertion hole into which an operating hexagon wrench can be inserted and which has a smaller diameter than the head of the hexagon socket head bolt, and screwing the hexagon socket head bolt into the shaft end of the drive shaft, the impeller can be driven. It is characterized by being fixedly attached to the drive shaft.

〔Example〕

Hereinafter, one embodiment of the mounting structure for the pump impeller and pump shaft according to this invention will be described in detail with reference to FIGS. 1 to 4.

The structure of the embodiment shown in FIGS. 1 and 2 corresponds to the conventional structure, and the same reference numerals in these figures indicate the same or corresponding parts. A holding recess 15 is formed in the center of the hexagon socket head bolt 13 from the base side.
is fitted with some margin in the tightening direction, and is held and held by an annular locking nut 16 from the base side. That is, in the center of the impeller 9, the head 13a of the hexagonal socket bolt 13 can only be rotated freely within the corresponding part of the mounting hole 11 with a margin in the tightening direction, in other words, it can only be rotated for screwing forward and backward. It can be held freely. Note that 17 in the figure is a set screw for preventing the annular locking nut 16 from returning.

Therefore, in the case of this embodiment structure, the threaded part 13b of the hexagon socket head bolt 13 is connected to the annular locking nut 16, which has a slightly larger diameter than the threaded part 13b, which corresponds to the mounting hole 11 in the conventional example. It will be inserted into the inner diameter hole 16a. In addition, in order to screw the bolt 13 forward and backward from the outside of the impeller 9, that is, from the screw blade 10 side, a hexagonal wrench 18 is provided at the center of the tip of the impeller 9, which is engaged with a hexagonal hole in the head 13a. An insertion hole 19 is formed with a diameter large enough to insert into the holding recess 15 from the outside, in other words, an inner diameter sufficiently smaller than the outer diameter of the head 13a. Normally, the inner diameter of the insertion hole 19 at this time is
Approximately 1/2 of the inner diameter of the conventional example is sufficient for receiving the head 13a. That is,
As a result, with the structure of this embodiment, the position of the root portion 10a of the screw blade 10 with respect to the impeller 9 can be reduced to about 1/2 compared to the conventional structure. The influence on the blade shape can be kept as small as possible, the flow path shape can be made smoother, and the passage of foreign matter in this part can be improved.

On the other hand, in the case of this embodiment structure, the base side of the impeller 9 is fitted into the flange portion 7a of the hub member 7 with a spigot, and the hexagon socket head bolt 13 is tightened to the shaft end portion 5a of the drive shaft 5. The operations for attaching and detaching the garment can also be carried out very easily.

That is, first, as shown in FIG. 3, the installation operation is performed by engaging the hexagonal wrench 18 in the hexagonal hole of the head 13a of the bolt 13 through the insertion hole 19, and then moving the hexagonal wrench 18 in the spiral direction. By this operation, the head 13a comes into contact with the front surface of the annular locking nut 16, and the annular locking nut 16 is pushed in, thereby facilitating installation. In addition, for the removal operation, simply rotate the hexagonal wrench 18 in the screwing-back direction in the previous state, and by this operation, the head 13a will come into contact with the rear surface of the holding recess 15, and will move in the direction to pull it out. Even if the spigot fitting part is so tightly fitted that it becomes difficult to remove it, it can be easily removed by the action of a so-called screw.

[Effect of idea]

As is clear from the above explanation, according to the present invention, although it is necessary to screw the bolt into the shaft end of the drive shaft, the size of the hole formed at the center of the tip of the blade is small. The position of the base of the pump blade relative to the impeller can be made smaller. Therefore, the flow path can be formed into a smooth shape, and the passage of foreign matter in this portion can be improved.

In addition, by operating the hexagon socket bolt, you can not only attach and detach the hexagon socket bolt to the shaft end of the drive shaft, but also attach and detach the impeller to and from the hub member.
This can be done at the same time, including in-row fitting. In other words, the pump impeller and the pump shaft can be disassembled very easily with just a hexagonal wrench for operating the hexagonal socket bolt.

[Brief explanation of the drawing]

Fig. 1 is a sectional view showing an embodiment of the mounting structure between the pump impeller and the pump shaft according to this invention;
The figure is a partial view seen from the line direction of the same as above, FIGS. 3 and 4 are explanatory views of the attached and removed states of the same impeller, respectively, and FIG. 5 is a sectional view showing a conventional structure. 1...Body housing, 2...Pump casing, 4...Suction cover, 5...Pump drive shaft, 5
a... Shaft end of drive shaft, 7... Hub member, 9...
Pump impeller, 10...Pump blade, 11...Mounting hole, 13...Hexagon socket head bolt, 13a, 13
b……Hexagon socket head bolt head, threaded part, 15……
Holding recess, 16... Annular locking nut, 16a...
Inner diameter hole of annular locking nut, 18...hexagonal wrench,
19...Insertion hole.

Claims (1)

[Scope of utility model registration request] A hub member is supported on the pump drive shaft, the base side of the pump impeller is prevented from rotating on the hub member and fitted with a spigot, a holding recess is formed in the center of the impeller from the base side, and a holding recess is formed in the center of the impeller from the base side. The head of the hexagon socket head bolt is fitted with a margin in the tightening direction, and the head of the hexagon socket head bolt is held from the base side of the impeller by an annular locking nut screwed into the holding recess. The hexagonal wrench for bolt rotation operation can be inserted from the outside into the holding recess at the center of the tip of the impeller, and the hexagonal wrench is smaller in diameter than the head of the hexagon socket head bolt. A pump impeller and pump characterized in that the impeller is fixedly attached to the drive shaft by forming an insertion hole and screwing the hexagon socket head bolt into the shaft end of the drive shaft. Mounting structure with shaft.