GB2124302A

GB2124302A - Self-priming pump

Info

Publication number: GB2124302A
Application number: GB08313716A
Authority: GB
Inventors: Yoji Mori
Original assignee: World Chemical KK
Current assignee: World Chemical KK
Priority date: 1982-05-29
Filing date: 1983-05-18
Publication date: 1984-02-15
Also published as: FR2527703A1; IT8321300A0; JPS58210397A; IT1237338B; GB8313716D0; DE3318548A1

Abstract

The pump is provided with a main suction chamber 46 and an auxiliary chamber 48 communicating with the main suction chamber via holes 66a, 66b, a priming chamber 18 equipped with a separating plate 72 for separating air from the pumped liquid, a hole 130 for connecting the priming chamber with the chamber 48 and a pump housing 32 enclosing an impeller 34. The impeller includes pumping blades 112 and sealing blades 114. The pump housing is provided with priming holes (104, Fig. 1) and 126. When the pump is stopped, liquid flows reversely from the outlet to the inlet until its level reaches the hole 130 which then allows air to pass into the chamber 48 to stop the siphoning action and retain priming liquid in the chambers 46, 48. <IMAGE>

Description

SPECIFICATION Self-priming pump The present invention relates to a self-priming pump and, more particularly to a self-priming pump having a pumping chamber defined by a casing providing an inlet and an outlet with pumped fluid being directed through the outlet depending upon the rotation of the pump impeller.

In recent years, many kinds of self-priming pumps have widely been used in order to pump up chemical liquid.

Further, operation of the pump has been simplified and therefore operators who are skilled to the operation of the pump are few.

Under these conditions, the pump for use with treating the chemical liquid is manufactured by selecting materials in the form of synthetic resin, metal and the like. When the pump is operated under no load condition, serious malfunction, however, can be generated by the thermal deformation due to the contact of a rotating portion with a fixed portion of the pump.

Further, the bearing of the pump is provided with a rotating portion. Crystallized material produced by a chemical reaction, slurry of the like in the chemical liquid can adhere to the rotating portion of the bearing of the pump. Accordingly, abnormal abrasion can occur to the rotating portion of the pump and thereby leakage of the liquid can appear as a result of wear on a surface of a mechanical seal.

A liquid enclosing means and a sliding means of the pump are provided with a sealing member and a rotating member. Generally, most of the malfunctions in the pump are generated at the liquid enclosing means and the sliding member, because these have, a respective sliding portion and rotation portion. A non-return valve can be used in order to store the liquid when the operation of the pump ceases. The flow of liquid in the pump is reversed by a siphoning operation in case dust and slurry engage with the non-return valve and thereby the pump becomes empty.

An object of the invention is to provide a selfpriming pump which can eliminate the above disadvantages.

More specifically, an object of the invention is the provision of a self-priming pump in which a mechanical non-return valve is not used and the priming liquid can be stored in a pump housing by employing a suctioning chamber and a small siphoning hole.

According to the present invention, there is provided a self-priming pump which comprises in condition; pumping means including a housing defining an inlet and an outlet and for enclosing liquid to be pumped, liquid transferring means provided in said housing and for transferring the liquid in said housing, a suctioning member provided in said housing and for sucking the liquid from said outlet into the housing and a priming member for priming the liquid into said housing in a priming operation of said pumping means, driving means for driving said pumping means, and liquid storing means for storing the liquid in said housing when pumping operation of said pumping means is ceased, said liquid transferring means comprising a pump housing provided in a lower portion of said housing, an impeller provided within said pump housing and connected to said driving means, a vortex chamber formed between an inner wall of said pump housing and said impeller, and a sealing means for preventing injection of the liquid and air into said vortex chamber, said priming member including separating means for separating the air from the liquid to be pumped, and said liquid storing means siphoning means for siphoning the liquid from said priming member to said suctioning member.

An embodiment of the invention will now be described by way of example with reference to the accompanying drawings in which: Figure 1 is a sectional front view of an embodiment of a self-priming pump according to the present invention; Figure 2 is a diagrammatical sectional view of the embodiment shown in Figure 1, taken on the line Il-Il of Figure 1; Figure 3 is a sectional view of the self-priming pump shown in Figure 2, taken on the line Ill-Ill of Figure 2; Figure 4 is a sectional view of the embodiment of the self-priming pump according to the present invention, taken on the line IV--IV of Figure 3; Figure 5 is a sectional view of the embodiment of the self-priming pump, showing a pump housing taken on the line V-V of Figure 1;; Figure 6 is a sectional view of the pump housing, taken on the line VI--VI of Figure 5; Figure 7 is a partial sectional view of the pump housing and an impeller of the self-priming pump according to the present invention; Figure 8 is an upward plan view of one form of an impeller for use with the embodiment of the self-priming pump according to the present invention; and Figure 9 is a downward plan view of one form of an impeller for use with embodiment of the selfpriming pump according to the present invention.

With reference to Figure 1 of the drawings, there is shown a self-priming pump according to the present invention.

The self-priming pump 10 comprises pumping means for pumping the liquid and driving means for driving the pumping means.

The pumping means comprises a housing 12 for enclosing the liquid therein, a liquid transferring member 14 for transferring the liquid, a suctioning member 16 for sucking the liquid from an outlet portion into the housing 12, a priming member 1 8 for priming the liquid into the housing 12, an inlet 20 communicating with the suctioning member 16, and an outlet 22 communicating with the housing 12. The driving member comprises an electric motor 26.

As shown in Figure 1 , the housing 12 is generally formed by fastening together two separate components, namely a bottom member 28 and a top member 30. Each member is preferably molded from a plastic such as polypropylene. It is seen that in the assembled position in Figure 1, the face-to-face engagement of the cooperating flange members on the top and bottom members compresses an O-ring by means of a ring coupling 36.

The liquid transferring member 14 includes a pump housing 32 which is provided within a lower portion of the housing 12, and an impeller 34 which is provided within the pump housing 32 and is fastened to a driving shaft 26a of the electric motor 26. The pump housing 32 is formed by fastening together two separate components, namely a bottom member 38 and a top member 40. The pump housing 32 further comprises a cylindrical tubular portion 42 which is connected to the top member 40, and a flange portion 44 extendir,g radially outwardly from one end of the tubular portion 42.

As is best shown in Figures 1 and 2, the suctioning member 1 6 comprises a main suctioning member 46 communicating with the inlet aperture 20 and an auxiliary suctioning chamber 4-6 positioned inner side of the main suctioning chamber 46. A first partition wall 50 is verticaliy provided between the top member 40 of the pump housing 32 and the housing 12. As is best shown in Figure 2, the partition wall 50 is formed by a rectangular first partition plate 52 which is secured to an outral edge of the top member 40 of the pump housing 32, a second partition plate 54 and a third partition plate 56.

The main suctioning chamber 46 is formed between the partition wall 50 and an inner wall of the housing 12.

As is best shown in Figure 2, a second partition wall 58 is provided between the tubular portion 42 of the pump housing 32 and the housing 12.

The second partition wall 58 is formed by a fourth partition plate 60 and a fifth partition plate 62 which are secured, respectively, to an outer surface of the tubular portion 42 of the pump housing 32 and the inner wall of the housing 12 spaced apart a predetermined angle each other.

A cover plate 64 is provided between the first partition wall 50, the second partition wall 58 and the inner wall of the housing 12. As is shown in Figures 1 and 2, the auxiliary suctioning chamber 48 is formed by the first partition wall 50, the second partition wall 58 and the inner wall of the housing 12. The first partition plate 52 is provided with holes 66a and 66b to communicate between the main suctioning chamber 46 and the auxiliary suctioning chamber 48.

As is shown in Figures 2 and 3, a third partitioning member 68 is provided between the partition plate 60 and the inner wall of the housing 1 2 to form an outleting chamber 70. A separating plate 72 is mounted between the second partitioning member 58, the third partitioning member 68 and the inner wall of the housing 12 to form a priming chamber 76 of the priming member 1 8. The separating plate 72 is provided with a plurality of separating holes 74 for separating the liquid and the air.

As is shown in Figure 1 , the bottom member 28 of the housing 1 2 includes a radially outwardly projecting flange. The radially lowermost portion of the top member 30 defines a flange in opposed facing relation of the flange of the bottom member 28. The top member 30 includes a tubular portion, the inlet aperture 20 and the outlet aperture 22.

The inlet aperture 20 is generally larger than the outlet aperture 22 and its associated nipple portion extends generally tangentially from the tubular portion of the top member 30 of the housing 1 2.

The bottom member 28 of the housing 12 includes a generally planar bottom wall 78 and an upstanding peripheral side wall 80 with the juncture between the side wall and the bottom wall 78 radiused so as to provide a generally smoothed contour.

As is shown in Figures 1,3 and 6, the bottom member 38 of the pump housing 32 centrally defines an opening 82. The bottom member 38 includes a generally planar bottom wall 84, a first vertical and upstanding peripheral side wall 86, a stepped flat wall 88 communicating with the first vertical side wall 86 and a second vertical and upstanding portion 90 communicating with the annular stepped flat portion 88.

As is shown in Figures 1 and 3, the top member 40 of the pump housing 32 includes a first stepped flat wall 92 formed in an inner side of the outermost periphery of the top member 40, a first annular projection 94 projecting from the stepped flat portion 92 toward the inner side of the pump housing 32, a second annular projection 96 projecting from the top wall 40 and positioned in the inner side of the pump housing 32. An annular slot 98 is formed between the first projection 94 and the second projection 96. The central portion of the top member 40 centrally defines an aperture defined by a vertical sleeve 102. As is shown in Figures 1,4 and 7, a balancing hole 104 is provided in the top member 40 so as to be positioned in the annular slot 98.The stepped flat wall 92 of the top member 40 is secured to an end portion of the second vertical and upstanding portion 90 of the bottom member 38.

The impeller 34 is disposed within the pump housing 32 in driving engagement with the driving shaft 26a of the motor 26. The impeller 34 includes a central hub portion 106 having a threaded hole 108 which telescopically receives the driving shaft 26a of the motor 26 therein. The impeller 34 is fastened to the end portion of the driving shaft 26a.

As is best shown in Figures 7, 8 and 9, the impeller 34 extends radially outwardly from the hub member 106 forming a generally planar bottom wall 84, the bottom face of which is in close facing relationship with the bottom wall 84 of the bottom member 38. The lower face of the impeller's bottom wall supports a plurality of pumping blades 112 which have an arcuate configuration to provide a pumping capability in either direction of rotation of the impeller 34, however, with the pump capacity of the blade in one direction being substantially more efficient that the pumping capacity of the first impeller blade 112 in the opposite direction.

As is best shown in Figure 7, the impeller 34 comprises a hub member 106, a disc plate 110, a plurality of liquid sealing blades 114 projecting from the disc plate 110 toward the bottom wall 84 of the bottom member 32, an annular projection 11 6 vertically projecting from the upper surface of the disc plate 110 toward the annular slot 98. The peripheral edge portion 11 8 of the disc plate 110 is positioned within the second slot 119.

A narrow gap 122 is formed with the second annular projection 96, the first annular projection 94, and the upstanding portion 90 of the pump housing 32, the disc plate 110, the sealing blades 114 and the peripheral edge portion 118 of the impeller 34. The pump housing 32 is provided with a balancing hole 104 in the top member 40 of the pump housing 32 and a vortex chamber 124 which is formed between the inner wall 84 of the bottom member 86 of the pump housing 32.

As is shown in Figures 1 and 3, a priming hole 126 is provided at the bottom wall 84 of the pump housing 32 so as to be communicated with the voltex chamber 124. An outlet chamber 128 is formed between the side wall 80 of the housing 80 and.the pump housing 32 and the priming chamber 1 8. A siphoning hole 130 is provided in a wall of the auxiliary suctioning chamber 48 such that it is located to the upper portion of the outleting chamber 140 and it communicates the priming chamber 1 8 and the auxiliary suctioning chamber 48.

In the conventional self-priming pumps, a suctioning chamber is designed to be smaller than a priming chamber. A non-return valve is, therefore, employed in order to store the priming liquid in the priming chamber. According to the present invention suctioning member 1 6 is designed so as to be same volume with that of the priming chamber 1 8 and, therefore, the priming water is stored by means of the operation of the siphoning hole 130.

The siphoning hole 130 is provided on a wall of the auxiliary suctioning chamber 48 so as to communicate the priming chamber 1 8 with the auxiliary suctioning chamber 48. In the priming operation of the pump, the liquid in the pump housing 1 2 passes through the siphoning hole 130. The suctioning member 1 6 which comprises the main and auxiliary chambers 46 and 48 hold the vacuum pressure therein in the driving operation of the pump. When the pumping operation of the pump is stopped, the water level goes down and thence the air is absorbed into the inlet 20 by way of the siphoning hole 1 30 and the suctioning member 1 6 to stop the siphoning operation.

The auxiliary suctioning chamber 48 stores the water although the water flows reversely toward the inlet 20 and thereby the water of the main suctioning chamber 46 flows reversely toward the inlet 20 when the rotation of the impeller 34 is stopped. In the priming operation of the pump, the second suctioning chamber 48 is ejected toward the main suctioning chambers 46 through the communicating hole 66a and 66b. The water of the main suctioning chamber 46 is transferred to the priming chamber 1 8 by the operation of the impeller 34.

When the priming operation is finished, the water in the main suctioning chamber 46 flows toward the auxiliary suctioning chamber 48 through the communicating holes 66a and 66b, and thence the water is fulfilled into the auxiliary suctioning chamber 48.

The water in the priming chamber 18 is absorbed through the balancing hole 104 by the centrifugal operation of the impeller 34 and thereby the central lower portion in the impeller housing 34 becomes negative pressure. In case that the balancing hole 104 is not provided, the air injects into the voltex chamber 1 24 by the operation of the sealing blades 114 of the impeller 34. The balancing hole 104 operates to prevent the injection of the air into the voltex chamber 114, since the air supplied from the sleeve i 02 is moved toward the priming chamber 1 8 through the balancing hole 104.

The ring-shaped projection 11 6 interrupts the flow of air toward the priming blades 112 of the impeller 34. The air is transferred from the suctioning member 16 to the priming chamber 18.

The air in the priming chamber 1 8 is separated from the water by means of the separating plate 72. When the priming chamber 18 is not provided with the separating plate 72, the water and the air bubbles in the priming chamber 18 is moved toward the priming blades 112 of the impeller 34 by way of the balancing hole 104 due to the violent turbulent flow. By the aid of the separating plate 72, the air is separated from the water, and thereby the water is absorbed into the outleting chamber 128 through the priming hole 126 of the pump casing 34.

In the self-priming pump described foregoing, the priming water is initially inserted into the priming chamber 18. When the impeller 34 is rotated by the electric motor 26, the liquid in the form of the water is suctioned into the housing 12 from the inlet 20 and is ejected from the outlet 22.

In more detail, the water suctioned into the housing 12 is supplied into the suctioning member 1 6. The water suctioned into the main suctioning chamber 46 of the suctioning member 1 6 is supplied into the auxiliary suctioning chamber 48 through the communicating holes 66a and 66b.

The water suctioned into the main suctioning chamber 46 of the suctioning member 1 6 is also supplied into the pump housing 32 through the opening 82 from the main suctioning chamber 46.

The water ejected from the main suctioning chamber 46 is transferred to the outleting chamber 70 and is ejected from the outlet 22 to the outer portion of the housing 1 2 by the operation of the pumping blades 112 of the impeller 34. The impeller 34 is rotated in the narrow gap 1 22 such that projections 11 6 and 118 do not contact with the inner wall of the pump housing 32.

In the priming operation of the pump 10, the friction of the liquid is produced in the narrow gap which is formed between the first annular projection 94, the second annular projection 96 of the upper member 40 of the pump housing 32, the ring-shaped projection 11 6 and the outer peripheral projection 11 8 of impeller 34 due to the viscosity of the liquid. The liquid in the narrow gap 122 is transferred to the upper surface and the liquid contacting with the upper surface is transferred toward the lower surface of the disc plate 110. These transferred liquid coincide with each other and is balanced, and thereby sealing operation is performed. Under these conditions, the narrow gap 22 functions as the resistor of the liquid.The water in the narrow gap 122 generates the voltex flow and the turbulent flow, and therefore the pumping blades of the impeller 34 is substantially apart from the sealing blade 114. A high speed voltex flow is generated in the voltex chamber 124 and thereby the high vacuum condition is obtained in the voltex chamber 124, since the injection of the air from the tubular portion 42 is avoided due to the narrow gap 122 of the pump housing 32. Accordingly the sealing operation is performed by the viscosity of the liquid.

Since the high vacuum of the voltex chamber 124 is lowered when the air is entered into the voltex chamber 124, the self-priming operation is lowered. The balancing hole 104 is provided in the pump housing 32 so as to be positioned in the vicinity of the sealing blades 114 in accordance with the present invention. Accordingly, the air injected from the sleeve 102 into the pump housing 32 is transferred into the self-priming chamber 1 8 through the balancing hole 104.

Injection of the water from the suctioning chambers 46 and 48 to the voltex is also prevented and thereby the high vacuum condition can be obtained in the voltex chamber 124 in order to enhance the ejecting pressure of the pump. By the enhancement of the vacuum pressure of the voltex chamber 124, the water is forced to be returned toward the sealing blades 114. Under these conditions, the leakage of the water is prevented by the high sealing performance in the narrow gap 122 and thereby the self-priming operation is enhanced.

The water in the main suctioning chamber 46 is transferred into the outleting chamber 70 (128) by the pumping operation of the pumping blades of the impeller 34 and thence is transferred toward outer portion of the pump housing 32 by way of the outlet 22.

The water including the air bubbles in the pump housing 32 is transferred to the separating chamber 1 8. The water of the separating chamber 1 8 is ejected toward the outlet 22 through the separating holes 74 of the separating plate 72.

The separating plate 72 functions as a rectifier for separating the air bubbles from the water. In more detail, the water and the air bubbles in the priming chamber 1 8 are ejected therefrom. The ejected air bubbles from the priming chamber 1 8 is outleted from the outlet 22 to the outer portion of the pump housing 1 2. On the other hand the water from the priming chamber 1 8 is returned into the priming chamber 1 8 through the separating holes 74.

When the pumping operation of the pump is stopped, the water of the tube connected to the inlet is reversedly flowed toward the outer portion of the pump housing 12 and thereby the negative pressure is generated in the main suctioning chamber 46. By the negative pressure in the main suctioning chamber 46, the water also flows reversely from the outlet 22 to the suctioning chamber 46. In this case, when the water level reaches the siphoning hole 130, the air enters into the auxiliary suctioning chamber 48 of the suctioning member 1 6 and thereby reverse flowing of the water is stopped. A part of the water stored in the auxiliary suctioning chamber 48 is supplied to the main suctioning chamber 46 through the communicating holes 66a and 66b by the siphoning operation.Accordingly, the water for priming is stored in the suctioning chambers 46 and 48.

Under these conditions, when the pump is operated again, the self-priming operation is securely performed since the priming water is fully stored in the pump housing 12. In more detail, the priming water stored in the main suctioning chamber 46 and the auxiliary suctioning chamber 48 is transferred toward the priming chamber 18 and toward the outlet 22 by means of the rotation of the impeller 34. These circulating operation of the priming water produces the vacuum pressure in the priming chamber 18, because the air of the priming chamber 1 8 is removed by the circulation of the water.By the priming operation of the pump, the water is suctioned into the suctioning member 1 6 and is also supplied to priming chamber 1 8 from the suctioning member 1 6 until the water is fulfilled to the pump housing 12.

When the water is fullfilled to the pump housing 12, the pump performs a continuous running operation.

According to the present invention, a selfpriming pump is provided with a siphoning hole, a suctioning member which comprises a main suctioning chamber and an auxiliary suctioning chamber communicating with the main suctioning chamber by communicating holes, a priming chamber equipped with a separating plate for separating the air from the water and a pump housing equipped with an impeller. The good priming performance of the pump can be obtained by the siphoning hole, the suctioning member and operations of the pump housing and the impeller.

Moreover, the self-priming pump of the present invention can perform the good priming performance and the good sealing operation without using a non-return valve, a sliding portion and a mechanical sealing member.

In view of above, it will be seen that the several objects of the invention are achieved and other advantageous results are attained.

While a preferred embodiment has been shown and described, it will be apparent to those skilled in the art that modifications can be made without departing from the principle and spirit of the invention, the scope of which is defined in the appended claims. Accordingly, rather than restricting of the invention and those modifications which come within the means and range of equivalency of the claims are to be included herein.

Claims

1. A self-priming pump comprising in combination; pumping means including a housing defining an inlet and an outlet and for enclosing liquid to be pumped, liquid transferring means provided in said housing and for transferring the liquid in said housing, a suctioning member provided in said housing and for sucking the liquid from said outlet into the housing and a priming member for priming the liquid into said housing in a priming operation of said pumping means; driving means for driving said pumping means; and liquid storing means for storing the liquid in said housing when pumping operation of said pumping means is ceased; said liquid transferring means comprising a pump housing provided in a lower portion of said housing, an impeller provided within said pump housing and connected to said driving means, a vortex chamber formed between an inner wall of said pump housing and said impeller, and a sealing means for preventing injection of the liquid and air into said vortex chamber; said priming member including separating means for separating the air from the liquid to be pumped; and said liquid storing means including siphoning means for siphoning the liquid from said priming member to said suctioning member.

2. A self-priming pump as claimed in claim 1, wherein said suctioning member comprises a main suction chamber provided in said housing and communicating with said inlet and an auxiliary.

suction chamber provided in said housing and located to an inner side of said main suction chamber and communicating means for communicating the main suction chamber with the auxiliary suction chamber.

3. A self-priming pump as claimed in claim 1, wherein said priming member comprises a priming chamber communicated with said pump housing through a balancing hole provided on the pump housing.

4. A self-priming pump as claimed in claim 1, wherein said separating means of said priming member comprises a separating plate provided on an upper portion and having a plurality of separating holes.

5. A self-priming pump as claimed in claim 2, wherein said main suction chamber comprises an inner wall of the housing, a partition wall vertically provided between the pump housing and the housing.

6. A seif-priming pump as claimed in claim 5, wherein said partition wall comprises a first partition plate secured to an outer edge of the housing, a second partition plate and a third partition plate which are provided between a tubular portion of the pump housing and said housing.

7. A self-priming pump as claimed in claim 2, wherein said auxiliary suction chamber comprises a second partition wall provided between a tubular portion of said pumping housing and said housing and formed by a fourth partition plate and a fifth partition plate which are secured, respectively, to an outer surface of the tubular portion of the pump housing and an inner wall of said housing spaced apart a predetermined angle each other, and a cover plate provided between a first partition wall, the second partition wall and an inner wall of said housing.

8. A self-priming pump as claimed in claim 2, wherein said communicating means comprises a first communicating hole and a second communicating hole provided on a first side wall dividing the main and second suctioning chambers.

9. A self-priming pump as claimed in claim 3, wherein said priming chamber comprises a second partitioning plate provided between a tubular portion of the pump housing and an inner wall of the housing and a third partitioning member provided between a second partitioning plate and an inner wall of the housing and the separating plate provided on an upper portion of the priming chamber.

10. A self-priming pump as claimed in claim 1, wherein said siphoning means comprises a siphoning hole provided on an upper portion of a wall of the auxiliary suctioning chamber so as to communicate the priming chamber with said auxiliary suctioning chamber.

11. A self-priming pump as claimed in claim 1, wherein said sealing means of the liquid transferring member comprises a gap defined by an inner surface of said pump housing and said impeller.

12. A self-priming pump as claimed in claim 11 , wherein said pump housing comprises a bottom member and a top member, said bottom member includes a first vertical and upstanding peripheral side wall, an annular stepped flat wall communicating with said vertical side wall and a second vertical and upstanding portion communicating with said annular stepped flat portion, said top member includes a first stepped flat wall formed in an inner side of the outermost peripheral of the top member, a first annular projection projecting from said first flat portion toward the inner side of the pump housing, a second annular projection projecting from the top member and positioned in the inner side of the pump housing, an annular slot formed between said first annular projection and said second annular projection, said impeller includes a disc plate, a plurality of sealing blades projecting from said disc plate projecting toward the inner wall of said top member, an annular projection projecting from an upper surface of said disc plate and a peripheral edge portion of the disc plate positioned within a second slot formed between said first annular projection of the top member and said stepped flat portion of the bottom member of the pump housing, said gap is defined by said first annular projection of the top member, a second annular projection of the top member, said upstanding portion of the top member of said pump housing, said disc plate of the impeller, said sealing blades and said peripheral edge portion of the impeller.

1 3. A self-priming pump substantially as herein described with reference to the accompanying drawing.