JPS6337517Y2 - - Google Patents

Description

[Detailed explanation of the idea] (Industrial application field) The present invention relates to a self-priming pump.

(Prior art) A self-priming pump consists of a rotating main shaft protruding from a casing cover, an impeller attached to the rotating main shaft, a peripheral wall portion in which a discharge opening is formed, and an upper wall portion in which a suction cylinder portion is formed. The pump includes a volute case that covers the impeller and forms a pump chamber, and a pump case that is provided with a suction port and a discharge port and is attached to a casing cover so as to cover the volute case. To attach the volute case to the casing cover, fit the end of the suction port of the pump case into the suction cylinder of the volute case, and then attach the volute case to the casing at the end of the suction port with a sealing material interposed. It is pressed against the cover side, and the volute case is held and supported between the pump case and the casing cover.

(Problem that the invention aims to solve) Therefore, in the case of conventional self-priming pumps, the tightness of the sealing material varies due to variations in the dimensional accuracy of each component such as the pump case and volute case. It is difficult to support the pump with a constant tightening force, causing problems such as the volute case swinging during operation, and the sealing part being struck and worn out, reducing pump performance.

In particular, this type of pump has a mechanical seal attached to its rotating main shaft, and the pump case must be removed frequently to replace the mechanical seal.If you forget to tighten the mounting bolts on the case cover side of the pump case, etc. Support for the volute case is more unstable.

In order to solve this problem, it is possible to attach the volute case to the casing cover with bolts, but if the bolt attachment part protrudes irregularly from the volute case, the flow inside the pump will be disturbed and the pump performance will be affected. decrease.

The present invention was devised in view of the above circumstances, and the purpose of this fermentation proposal is to be able to attach the volute case to the casing cover with a constant tightening force, and to ensure that the flow inside the pump is To provide a self-priming pump that does not cause turbulence.

(Means for Solving the Problems) In order to achieve the above-mentioned object, the present invention forms a bolt mounting seat that protrudes from the peripheral wall of the volute case to the outside of the circumference of the peripheral wall, and the bolt mounting seat The height of is the same as the height of the peripheral wall of the volute case, insert the stud bolt installed in the casing cover into the bolt mounting seat, and tighten the nut on the stud bolt on the upper wall of the volute case. The volute case is removably attached to the casing cover by screwing together, and even if the dimensional accuracy of each component varies, the volute case can be attached to the casing cover with a constant tightening force, and bolt mounting seats, nuts, etc. It is characterized by suppressing as much as possible the turbulence that occurs in the flow inside the pump due to this.

(Embodiment) A preferred embodiment of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 is a sectional view of the main parts of a self-priming pump, and FIG. 2 is an exploded perspective view of the same.

The self-priming pump 1 consists of an engine 2 and a pump section 3.

A casing cover 5 is attached to the side surface of the engine 2 via bolts 4, and a rotating main shaft 7 is made to protrude from a boss portion 6 of the casing cover 5. A mechanical seal 11 is installed between the rotating main shaft 7 and the boss part 6, an impeller 12 is attached to the tip of the rotating main shaft 7 by screw connection, and stud bolts 13, 13 are installed around the bearing part 6 in the casing cover 5. to be planted.

The volute case 21 is attached to the casing cover 5 so as to cover the impeller 12. A front view of the volute case 21 is shown in FIG. 3, and a sectional view taken along the line -- in FIG. 3 is shown in FIG.

The volute case 21 includes a substantially spiral peripheral wall portion 23 to define a pump chamber 22 and an upper wall portion 24 close to the upper edge of the impeller 12 . are provided protrudingly, and discharge ports 26, 26 are opened in the peripheral wall portion 23.

Mounting seats 31, 31 for bolt insertion are uniformly bulged out along the height direction of the peripheral wall 23 on the outer side of the peripheral wall 23, and the bolt insertion holes 32 are formed on a virtual extension surface of the outer surface of the peripheral wall 23. It is provided close to the peripheral wall portion 23 side so as to be in contact with the peripheral wall portion 23 side.

The stud bolts 13 are inserted through the mounting seats 31, 31, respectively, and the volute case 21 is tightened and fixed to the casing cover 5 on the upper wall portion 24 using a cap nut 33.

A pump case 43 is attached to the casing cover 5 via a case seal O-ring 41 and a bolt 42.
, and fit the end 44a of the suction port 44 of the pump case 43 into the cylindrical portion 25 of the volute case 21 with the center seal ring 45 interposed,
Press the volute case 21 toward the casing cover 5 side.

A discharge port 47 is attached to the upper part of the pump case 43 via a bolt 46, and 48 in the figure is a handle.

The present invention is constructed as described above, and the outer peripheral part of the volute case 21 is attached to the casing cover 5 via the stud bolts 13 and the cap nut 33, so that the volute case 21 is attached to the casing cover 5 by a constant tightening force. 5, and even if the mounting bolts 42 of the pump case 43 are forgotten to tighten, the volute case 21 can be prevented from swinging during operation, and the durability of the center seal ring 45 can be increased.

In addition, since the upper surface of the bolt mounting seat 31 is formed high up to the upper surface of the bolt case 21, the necessary nut 33 can be attached by lowering the bolt mounting seat 31.
Since there is no need for a play interval between the peripheral wall 23 and the peripheral wall 23, the amount of the mounting seat 31 that bulges outward from the peripheral wall 23 can be reduced. This, together with the fact that the height of the mounting seat 31 is the same as the height of the peripheral wall 23 and there is no step, makes it possible to minimize the disturbance caused in the flow inside the pump 3 due to the mounting seat 31. Can be suppressed.

In addition, since the volute case 21 is attached to the casing cover 5 using stud bolts 13, it is possible to easily tighten the cap nut 33 when disassembling the pump case 43 and volute case 21 when replacing the mechanical seal 11. Even if this occurs, the rotation of the volute case 21 itself is prevented by the stud bolts 13, 13, and the pump 3 can be operated normally.

(Effect of the invention) As is clear from the above explanation, according to the invention,
Even if the dimensional accuracy of each component such as the pump case or volute case varies, the volute case can be attached to the casing cover with a constant tightening force, and the volute case can be attached to the casing cover using bolts. Even though the bolt mounting seat is installed at the same height as the peripheral wall of the volute case, no height difference is formed in the discharge channel from the volute case.
Furthermore, since the amount of protrusion of the mounting seat that bulges out into the discharge waterway is made small, turbulence in the internal flow caused by bolt attachment is suppressed to a minimum. This also has a particularly important meaning when this type of pump handles water that is likely to cause friction, etc., mixed with dirt or the like. Another advantage is that even if the bolts become loose, the stud bolts keep the volute case stable.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of essential parts of a self-priming pump, FIG. 2 is an exploded perspective view of the same, FIG. 3 is a front view of a volute case, and FIG. 4 is a cross-sectional view of FIG. 3. In the drawing, 1 is a self-priming pump, 5 is a casing cover, 7 is a rotating main shaft, 11 is a mechanical seal,
12 is an impeller, 13 is a stud bolt, 21 is a volute case, 43 is a pump case, and 45 is a center seal ring.

Claims (1)

[Scope of Claim for Utility Model Registration] The impeller comprises an impeller attached to a rotating main shaft protruding from a casing cover, a peripheral wall portion in which a discharge opening is formed, and an upper wall portion in which a suction cylinder portion is formed. A volute case that covers the volute case to form a pump chamber, and a pump case that is provided with a suction port and a discharge port and that covers the volute case and is attached to a casing cover, the end of the suction port being connected to the suction tube. In the self-priming pump, the volute case is pressed against the casing cover side at the end of the suction port with a sealing material interposed between the volute case and the volute case. A bolt mounting seat protruding outward from the circumference is formed, and the height of the bolt mounting seat is the same as the height of the peripheral wall of the volute case, and the stud bolt installed in the casing cover is attached to the bolt mounting seat. A self-priming pump characterized in that the volute case is removably attached to a casing cover by inserting the volute case into the casing cover and screwing a nut onto the stud bolt on the upper wall of the volute case.