DEVICE FOR DETERMINING THE DIRECTION OF ROTATION OF THE IMPELLER OF A PUMP

Abstract

A fan cover for protection of an impeller, said impeller arranged to rotate about a rotation axis x producing a consequent fluid flow, said fan cover comprising a protection wall defining an inner volume arranged, in use, to house the impeller and an indicator comprising a planar portion having a first face and a second face. In particular, the protection wall comprises at least one through hole and the indicator is arranged, in use, at the through hole with the planar portion at least partially within the inner volume, in such a way that, when the impeller rotates in a first direction, the fluid flow generates a pressure on the first face moving the indicator in a first position, and, when the impeller rotates in a second direction, the fluid flow generates a pressure on the second face moving the indicator in a second position.

Description

FIELD OF THE INVENTION

The present invention relates to the field of electric pumps for the industrial and domestic market.

In particular, the invention relates to a device for determining the direction of rotation of the impeller of a pump.

DESCRIPTION OF THE PRIOR ART

As well known, the direction of rotation of an impeller inside a centrifugal pump is of fundamental importance to ensure maximum compression efficiency.

However, in the case of pumps powered by three-phase electric motors in alternating current, it may happen that this direction of rotation is incorrect due to an involuntary inversion of the phases during connection to the power supply. This aspect can be particularly burdensome in terms of time for the operator, as most of the time it is possible to realize that the direction of rotation is wrong only after having completed the installation of the system.

Therefore, it is extremely useful to provide the operator with an indicator that allows you to check the right direction of rotation of the impeller when connecting to the power supply.

A first example of such devices is shown in DE2532436, in which the fan cover provides a tab hinged to it and pushed by the air flow generated by the impeller. In the event that the impeller rotates in the wrong direction, the tab is pushed towards a stop which causes it to touch the impeller blades, causing a noise used as a sound signal for incorrect rotation.

However, this system has first of all the drawback of severe wear of the tab and, secondly, the difficulty for an operator to receive the sound signal within noisy environments, very frequent in this sector.

To overcome these drawbacks, U.S. Pat. No. 8,777,586 describes a device capable of providing a visual and contactless signal between the indicator and the impeller blades. In particular, this indicator device includes a tab arranged near the impeller in such a way that the air flow can move it to a first position in the event of a correct direction of rotation and to a second position in the event of an incorrect direction of rotation. A shaft connected to this tab then transmits the assumed position to an element external to the fan cover, allowing the operator to check the direction of rotation of the impeller.

However, this solution also has various drawbacks. Firstly, the presence of a transmission shaft, in a device of necessarily reduced dimensions and subject to strong vibrations, can result in a structurally weak point of the indicator, with low reliability over time and high probability of fatigue failure. Furthermore, in order to be able to use it on existing pumps, in this solution the indicator is completely separate from the fan cover, facilitating its loss during transport and installation of the system. A further disadvantage lies in the fact that, once the indicator is installed in the fan cover and having used it for a first test, the indicator is not easily accessible for a second use, requiring the disassembly of the entire fan cover.

SUMMARY OF THE INVENTION

It is therefore a feature of the present invention to provide a fan cover for protection of an impeller which allows the direction of rotation of the impeller to be viewed without the need for installation of external components.

It is also a feature of the present invention to provide such a fan cover which comprises an indicator not subject to severe wear and with high reliability over time.

It is also a feature of the present invention to provide such a fan cover which comprises an indicator which can be easily removed from the fan cover itself and which can be reused or reset for tests subsequent to the first.

It is also a feature of the present invention to provide such a fan cover that includes an indicator that can be easily locked in its position during transport and/or during full operation of the pump once the installation phase is completed.

These and other objects are achieved by a fan cover for protection of an impeller, said impeller arranged to rotate about a rotation axis x producing a consequent fluid flow, said fan cover comprising:

• • a protection wall defining an inner volume arranged, in use, to house said impeller, said protection wall comprising a front face and a lateral face;
  • an indicator comprising a planar portion having a first face and a second face;
  • whose main feature is that said protection wall comprises at least one through hole arranged on said front face or on said lateral face,
  • and that said indicator is arranged, in use, at said through hole with said planar portion at least partially within said inner volume, in such a way that, when said impeller rotates in a first direction, said flow generates a pressure on said first face moving said indicator in a first position and, when said impeller rotates in a second direction, said flow generates a pressure on said second face moving said indicator in a second position.

With respect to the solutions of the prior art, the present invention integrates the indicator into the fan cover itself, requiring fewer components and increasing overall reliability.

Advantageously, said indicator comprises an indication portion integrally connected to said planar portion and said indicator is inserted, in use, in said through hole with said indication portion at least partially external to said inner volume, in such a way that outside of said protection wall is visible if said indicator is in said first position or in said second position.

Alternatively, said indicator is arranged entirely within said inner volume and said or each through hole is adapted to show outside of said protection wall if said indicator is in said first position or in said second position.

This solution allows to have the indicator completely inside the volume of the protection wall, avoiding possible damage due to impacts of the protection wall itself.

In particular, said indicator is, in use, arranged to rotate with respect to said protection wall to move to said first position or to said second position.

In particular, the axis x′ around which the indicator rotates is parallel to the axis x around which the impeller rotates.

Alternatively, the axis x′ is orthogonal to the axis x.

Advantageously, said protection wall comprises a single through hole and said indicator is, in use, rotatably connected to said protection wall at said through hole.

This solution allows to reduce the exposed area and to fully cover the opening light by means of the indicator pivot pin.

Alternatively, the protection wall comprises a first through hole and a second through hole.

Advantageously, the indicator is, in use, rotatably connected to the protection wall in a position substantially equidistant from the through holes, so that the first through hole shows the first face when the indicator is positioned in the first position and the second through hole shows the second face when the indicator is in the second position.

Advantageously, transparent protective plates are provided in correspondence with the through holes.

In particular, said indicator is, in use, arranged to translate with respect to said protection wall to move to said first position or to said second position.

Advantageously, said indicator is removably inserted in said through hole.

In particular, a locking means is provided arranged to prevent the rotation of said indicator.

Advantageously, said locking means comprises a plug configured to be inserted in said through hole to prevent said indicator from escaping from said through hole, said plug being suitably shaped to prevent the rotation of said indicator.

Advantageously, said first face is visually distinguished from said second face.

For example, the first and second faces have different colours, or identifying marks, or writings.

According to another aspect of the invention, it is also claimed a motor pump arranged to increase the pressure of a fluid, said motor pump comprising:

• • an impeller arranged to rotate about a rotation axis x to generate a fluid flow;
  • an electric motor arranged to rotate said impeller about said rotation axis x;
  • a fan cover according to one of the claims from 1 to 9.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be now shown with the following description of some exemplary embodiments, exemplifying but not limitative, with reference to the attached drawings in which:

FIG. 1 schematically shows a section of a possible embodiment of the fan cover according to the present invention;

FIG. 2 schematically shows a section of a possible embodiment of the fan cover according to the present invention;

FIG. 3 schematically shows a section of a possible embodiment of the fan cover according to the present invention;

FIG. 4 schematically shows a section of a possible embodiment of the fan cover according to the present invention;

FIGS. 5A and 5B schematically show two perspective views of a possible embodiment of the fan cover according to the present invention;

FIGS. 6A and 6B schematically show two perspective views of a possible embodiment of the fan cover according to the present invention;

FIG. 7 shows a perspective view of an application solution of the embodiment of FIG. 1;

FIG. 8 shows a section of the embodiment of FIG. 7;

FIG. 9A shows in detail a cross-section of the section FIG. 8;

FIG. 9B shows the cross-section FIG. 9A where it is also present a plug.

DESCRIPTION OF SOME PREFERRED EXEMPLARY EMBODIMENTS

In FIGS. 1 to 6B are schematically shown some possible embodiments of the fan cover 100, according to the present invention, for protection of an impeller 200 arranged to rotate about a rotation axis x.

In particular, the fan cover 100 comprises a protection wall 110 defining an inner volume 111 inside which, in use, the impeller 200 resides. In particular, the protection wall 110 comprises a front face 110′ and a lateral face 110″.

The fan cover 100 further comprises an indicator 120 comprising a planar portion 125 having a first face 125a and a second face 125b. In particular, the indicator 120 is arranged, in use, at least at one through hole 115 present in the protection wall 110 and is located in such a way that the planar portion 125 is arranged at least partially inside the inner volume 111. In particular, the through hole 115 can be located on the lateral face 110″ or on the front face 110′.

This way, when the impeller 200 rotates in a first direction, the flow generates a pressure on the first face 125a moving the indicator 120 in a first position, while, when the impeller 200 rotates in a second direction, the flow generates a pressure on the second face 125b moving the indicator 120 in a second position.

As described below, the present invention provides different solutions that allow to view from the outside whether the indicator 120 is in the first position or in the second position.

In this way, an operator who carries out the installation, for example, of an electric pump, can check that the direction of rotation of the impeller pump is correct, as soon as the electric motor connected to it is connected to the power supply, avoiding the risk of installing the entire system with an incorrect direction of rotation of the impeller.

Furthermore, all the embodiments of the present invention provide that the indicator 120 is substantially integrated in the fan cover 100, requiring fewer components than the prior art and thus increasing the overall reliability.

In particular, in the embodiments of FIGS. 1 and 2, the indicator 120 is adapted to rotate with respect to the protection wall 110. This way, the indicator 120 can rotate about its own axis as a consequence of the air flow generated by the impeller 200.

Therefore, when the impeller 200 rotates clockwise (as in FIGS. 1 to 4), the air flow generates a pressure on the first face 125a making the indicator 120 rotate counterclockwise, and, when the impeller 200 rotates counterclockwise, the air flow generates pressure on the second face 125b causing the indicator 120 to rotate clockwise.

Furthermore, the indicator 120 is inserted inside the through hole 115 in such a way that an indication portion 126 is external to the protection wall 110. Thus, when the planar portion 125 rotates due to the air flow, the indication portion 126 rotates integrally, allowing to see from the outside of the protection wall 110 whether the indicator 120 is in the first position or in the second position, allowing to know the direction of rotation of the impeller 200.

In particular, the indication portion 126 can have visually distinguishable faces, for example of different colours, to facilitate control by the operator.

In particular, the indicator 120 can be pivotally connected to the protection wall 110, for example by means of a hinge, or it can be disposed in a removable manner in a circular seat.

Advantageously, both solutions shown in FIGS. 1 and 2 provide that the lateral edges 116 of the through hole 115 prevent the indicator 120 from rotating beyond a predetermined angle.

With reference to FIG. 3, in one embodiment the invention provides that the indicator 120 is completely internal to the protection wall 110. In this embodiment, moreover, the protection wall 110 comprises two through holes 115 and 115′, in such a way that the first through hole 115 shows the first face 125a outward when the indicator 120 is positioned in the first position and the second through hole 115′ shows the second face 125b when the indicator 120 is positioned in the second position.

This embodiment therefore allows not to have an indication portion 126 that protrudes from the perimeter of the protection wall 110, avoiding possible damage to the indicator 120 due to impacts of the fan cover, for example during transport.

With reference to FIG. 4, in one embodiment the indicator 120 is not hinged to the protection wall 110 but is constrained to translate with respect to it to move to the first or second position.

This embodiment is advantageous in terms of reliability, since it avoids the presence of hinges which can potentially be damaged due to accidental impacts.

With reference to FIGS. 5A and 5B, in one embodiment the indicator 120 is rotatably connected to the protection wall 110 in correspondence with the indication portion 126 and it has an axis of rotation x′ orthogonal to the axis of rotation x of the impeller 200. In this embodiment, the planar portion 125 passes through the through hole 115 until it reaches the fluid flow present in the internal volume, as shown in FIG. 5B.

In this way, when the fluid flow generates a pressure on one of the two faces 125a, 125b, the indication portion 126 is made to rotate around the axis x′, showing externally whether the indicator 120 is in the first or second position.

With reference to FIGS. 6A and 6B, in a further embodiment the through hole 115 is arranged on the front face 110′ of the protection wall 110, instead of on the lateral face 110″, and it is crossed by the indicator 120, in such a way that the indication portion 126 is arranged on the front face 110′ itself. Similarly to the embodiments of FIGS. 1, 2 and 3, the indicator 120 is rotatably connected to the protection wall 110 and is able to rotate around an axis parallel to the axis of rotation x of the impeller 200.

This embodiment allows to better protect the indication portion 126 and not to have to make openings on the surface of the lateral face 110″.

In FIGS. 7 to 9B an application solution is shown of an embodiment of FIG. 1.

In particular, this embodiment provides that the indicator 120 is not integrally connected to the protection wall 110 and is disposed, in use, inside the through hole 115 in a removable manner, so as to be able to rotate with respect to the protection wall 110 thanks to the pins 126′.

Furthermore, with reference to FIGS. 7 and 9B, in this embodiment a plug 130 can be provided, which can be placed in correspondence with the through hole 115 and suitably shaped to prevent rotation of the indicator 120.

In this way, when the fan cover 100 is transported or handled, the plug prevents both the exit of the indicator 120 from the through hole 115 and the unwanted rotation of the same, which could cause wear and damage.

The foregoing description exemplary embodiments of the invention will so fully reveal the invention according to the conceptual point of view, so that others, by applying current knowledge, will be able to modify and/or adapt for various applications such embodiment without further research and without parting from the invention, and, accordingly, it is therefore to be understood that such adaptations and modifications will have to be considered as equivalent to the specific embodiments. The means and the 5 materials to realise the different functions described herein could have a different nature without, for this reason, departing from the field of the invention. It is to be understood that the phraseology or terminology that is employed herein is for the purpose of description and not of limitation.

Claims

1. A fan cover for protection of an impeller, said impeller arranged to rotate about a rotation axis x producing a consequent fluid flow, said fan cover comprising: a protection wall defining an inner volume arranged, in use, to house said impeller, said protection wall comprising a front face (110′) and a lateral face;an indicator comprising a planar portion having a first face and a second face;

2. The fan cover, according to claim 1, wherein said indicator comprises an indication portion integrally connected to said planar portion and wherein said indicator is inserted, in use, in said through hole with said indication portion at least partially external to said inner volume, in such a way that outside said protection wall is visible if said indicator is in said first position or in said second position.

3. The fan cover, according to claim 1, wherein said indicator is arranged entirely within said inner volume and wherein said or each through hole is adapted to show outside of said protection wall if said indicator is in said first position or in said second position.

4. The fan cover, according to claim 1, wherein said indicator is, in use, arranged to rotate with respect to said protection wall to move to said first position or to said second position.

5. The fan cover, according to claim 1, wherein said indicator is, in use, arranged to translate with respect to said protection wall to move to said first position or to said second position.

6. The fan cover, according to claim 2, wherein said indicator is removably inserted in said through hole.

7. The fan cover, according to claim 1, wherein a locking means is provided arranged to prevent the rotation of said indicator.

8. The fan cover, according to claim 6, wherein said locking means comprises a plug (130) configured to be inserted in said through hole (115) to prevent said indicator from escaping from said through hole (115), said plug (130) being suitably shaped to prevent the rotation of said indicator.

9. The fan cover, according to claim 1, wherein said first face is visually distinguished from said second face.

10. A motor pump arranged to increase the pressure of a fluid, said motor pump comprising: an impeller arranged to rotate about a rotation axis x to generate a fluid flow;an electric motor arranged to rotate said impeller about said rotation axis x;a fan cover according to claim 1.