JP2013181441A - Impeller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an impeller for preventing wear and damage on a sliding surface of the impeller by stably reducing sliding resistance, capable of reducing power loss and improving fuel efficiency due to reduction in rotational torque, and capable of reducing even a load applied to an adhesive surface between a blade part made of a rubber-like elastic material and a bush made of a metal material.SOLUTION: An impeller includes blade parts made of a rubber-like elastic material rotatably held in a pump housing and in elastic contact with an inner peripheral surface of the housing. In the impeller, the tip side of the blade part is covered with a U-shaped sheet member made of a fluororesin material.

Description

  The present invention relates to a pump impeller used for a cooling water pump, an bilge pump, etc. of an outboard motor engine, and more particularly to a pump impeller capable of preventing wear and seizure damage of the impeller generated during dry operation. Is.

2. Description of the Related Art Conventionally, pump impellers used in outboard engine engines such as cooling water pumps and pilge pumps have structures shown in FIGS.
That is, the impeller 100 is configured to include a blade portion 110 made of a rubber-like elastic material that is rotatably held inside the pump housing 200 and elastically contacts the inner peripheral surface 210 of the housing 200.
In this type of pump impeller, the water pumped up by the pump becomes a kind of lubricant in normal operation, so that seizure damage is unlikely to occur. Therefore, there has been a problem that the blade portion is damaged in a short time.

  Also, in order to compensate for the lack of lubricant during dry operation, PTFE (tetrafluoroethylene resin) coating on the rubber surface of rubber impeller pump impellers, oil application, and unevenness on the sliding surface However, (patent document 1) has a problem that durability and durability are poor due to peeling of the PTFE coating film, reduction of applied oil, uneven wear, and the like.

  Furthermore, the oil is directly kneaded into the rubber material constituting the impeller for the pump, so that the impeller is made of so-called oil-impregnated rubber, the workability and the metal made to be inserted into the center of the impeller There are also problems such as adhesion to the bushing, deterioration of the oil-containing oil, molding failure of the pump impeller itself, and the like, which makes it difficult to use.

JP 2011-21538 A Japanese Utility Model Publication No. 4-35594

  The present invention has been made in view of the above-described problems. By stably reducing the sliding resistance, the sliding surface of the impeller can be prevented from being worn and damaged, and the rotational torque can be reduced. Therefore, an object of the present invention is to provide an impeller that can be expected to reduce power loss and improve fuel efficiency, and at the same time reduce the load applied to the bonding surface between the rubber-like elastic material blade and the metal material bush.

  An impeller according to the present invention includes a blade portion made of rubber-like elastic material that is rotatably held inside a pump housing and elastically contacts an inner peripheral surface of the housing. It is characterized by being covered with a sheet member made of a U-shaped fluororesin material.

The present invention has the following effects.
According to the impeller of the first aspect of the invention, as a result of covering the tip end side of the blade portion with the sheet member made of the U-shaped fluororesin material, the sliding resistance can be permanently reduced, and therefore, for a long period of time. The impeller's sliding surface can be prevented from being worn and damaged, and the rotational torque can be reduced, reducing power loss and improving fuel efficiency. At the same time, blades and metal material made of rubber-like elastic material The load on the bonding surface with the bush made of steel can also be reduced.
According to the impeller of the invention described in claim 2, since the lip portion is provided on the sliding surface that comes into contact with the inner peripheral surface of the housing of the fluororesin material sheet member, the sliding resistance can be further reduced, and It is possible to firmly join the resin sheet member and the rubber elastic material blade.

According to the impeller of the invention described in claim 3, the durability of the sheet member can be improved by making the sheet member made of a tetrafluoroethylene resin material.
According to the impeller of the invention described in claim 4, since the fluororesin material sheet member and the rubber-like elastic material blades are driven in an integrated state over a long period of time, a long period of time is achieved. The wear and damage of the sliding surface of the impeller can be prevented and the rotational torque can be reduced.
According to the impeller of the invention described in claim 5, since the end portion of the sheet member is corrugated, the stress concentration generated at the end portion of the sheet member can be dispersed, so that the sheet member is peeled off or the blade portion is bent (seat Can be prevented.

The top view which shows embodiment of this invention. AA sectional drawing of FIG. The side view which has arrange | positioned the impeller of FIG. 1 in the housing for pumps. The elements on larger scale which show other embodiment of this invention. The figure which showed further another embodiment of this invention similarly to FIG. The impeller top view which concerns on a prior art. BB sectional drawing of FIG. The side view which has arrange | positioned the impeller of FIG. 5 in the housing for pumps.

The best mode for carrying out the present invention will be described below with reference to the drawings.
<First Embodiment>
1 to 3, an impeller 1 according to the present invention is rotatably held inside a pump housing 2, and a blade portion made of a rubber-like elastic material that is in elastic contact with an inner peripheral surface 21 of the housing 2. 11.
And the front end side of this blade | wing part 11 is covered with the sheet | seat member 12 made from a U-shaped fluororesin material.

The impeller 1 has a configuration in which a blade portion 11 made of a rubber-like elastic material such as chloroprene rubber (CR) or nitrile rubber (NBR) is integrally bonded to an outer peripheral surface of a bush 3 made of metal or resin. It has become.
The impeller 1 rotates by inserting a rotating shaft (not shown) into the bush 3.

Further, as shown in FIG. 3, the impeller 1 is arranged so that the rotation center axis is eccentric with respect to the center axis of the housing 2 when the impeller 1 is arranged in the pump housing 2.
In FIG. 3, the center of the impeller 1 is located on the right side with respect to the central axis of the housing 2.

For this reason, the space surrounded by the right wings 11 and 11 and the inner peripheral surface 21 of the housing 2 is narrower than the space surrounded by the left wings 11 and 11 and the inner peripheral surface 21 of the housing 2,
The liquid existing in the space surrounded by the right blades 11 and 11 and the inner peripheral surface 21 of the housing 2 is compressed and forcibly discharged from a discharge port (not shown).

  As the U-shaped sheet member 12 made of a fluororesin material, a tetrafluoroethylene resin, a trifluoride ethylene resin, a vinylidene fluoride resin or the like can be used, but from the viewpoint of wear resistance, a tetrafluoroethylene resin is used. preferable.

  In addition, the attachment to the blade portion 11 includes a method in which a sheet member 12 made of a fluororesin material, which has been previously formed into a U shape, is fixed to the tip of the blade portion 11 with an adhesive, and is formed into a substantially U shape. There is a method in which the sheet member 12 made of a fluororesin material is placed in a mold and is integrally formed when the blade portion 11 is formed.

Even when the sheet member 12 is attached to the blade part 11 by any method, the sheet member 12 is detached from the blade part 11 because the sheet member 12 is attached to the blade part 11 in a U-shaped state. However, as long as it fits in the housing 2, the sheet member 12 does not fall off the blade portion 11.
Further, since the sheet member is made of a fluororesin material, there is no fear of peeling from the blade portion like the PTFE coating film.

  In particular, such a configuration is effective for the sheet member 12 made of a fluororesin material that is difficult to be firmly bonded to other members.

  In this way, as a result of covering the front end side of the blade portion 11 with the sheet member 12 made of a U-shaped fluororesin material, the sliding resistance can be reduced permanently, so that the sliding of the impeller 1 over a long period of time can be achieved. The wear and damage of the moving surface can be prevented and the rotational torque can be reduced, so that reduction of power loss and improvement of fuel consumption can be expected. At the same time, the blade portion 11 made of rubber-like elastic material and the bush 3 made of metal material The load on the adhesive surface can be reduced.

Second Embodiment
A second embodiment of the present invention will be described based on FIG.
The difference from the above-described embodiment is that a lip portion 121 is provided on the sliding surface of the sheet member 12 on the side in contact with the inner peripheral surface 21 of the housing 2.

  And since the blade | wing part 11 of the impeller 1 is also lip-shaped corresponding to the lip | rip part 121, engagement with the sheet | seat member 12 and the blade | wing part 11 can be strengthened more.

  In this manner, since the lip portion 121 is provided on the sliding surface that contacts the inner peripheral surface 21 of the housing 2 of the sheet member 12 made of the fluororesin material, the sliding resistance can be further reduced, and The sheet member 12 and the rubber-like elastic material blade 11 can be firmly joined.

<Third Embodiment>
Based on FIG. 5, a third embodiment of the present invention will be described.
The difference from the above-described embodiment is that the end portion 122 of the sheet member 12 is not a linear shape but a wave shape as shown in the figure.
As a result, the stress concentration generated at the end 122 of the sheet member 12 can be dispersed, so that peeling of the sheet member 12 and bending (buckling) of the blade portion 11 can be prevented.
In the present embodiment, an arcuate wave shape is used, but a triangular wave shape may be used.
Moreover, although it is preferable that both the edge parts 122 and 122 of the sheet | seat member 12 are made into a wave shape, it is good also as an aspect provided only in the side with large deformation stress.

  Further, the present invention is not limited to the best mode for carrying out the invention described above, and various other configurations can be adopted without departing from the gist of the present invention.

  It is preferably used for a pump impeller used for an outboard engine cooling water pump, a bilge pump, or the like.

DESCRIPTION OF SYMBOLS 1 Impeller 2 Housing 3 Bush 11 Blade | wing part 12 Sheet | seat member 121 Lip part 122 edge part

Claims (5)

  An impeller (1) having a blade portion (11) made of a rubber-like elastic material that is rotatably held inside the pump housing (2) and elastically contacts the inner peripheral surface (21) of the housing (2). The impeller is characterized in that the front end side of the blade part (11) is covered with a U-shaped sheet member (12) made of a fluororesin material.   The impeller according to claim 1, wherein a lip portion (121) is provided on a sliding surface that contacts the inner peripheral surface (21) of the housing (2) of the seat member (12).   The impeller according to claim 1 or 2, wherein the sheet member (12) is made of a tetrafluoroethylene resin material.   The impeller according to any one of claims 1 to 3, wherein the sheet member (12) is integrally bonded to the blade portion (11).   The impeller according to any one of claims 1 to 4, wherein the end (122) of the sheet member (12) has a corrugated shape.

Images