Patent Application
20250180038
Water pumps are critical components in various machinery, responsible for circulating liquid to maintain optimal temperatures within a system coupled to the water pump. In watercraft and other applications, rubber impellers can be used in the water pumps to circulate water or coolant through the watercraft systems (e.g., engines, exhaust, transmissions, and/or other systems). Routine maintenance tasks, such as impeller replacement, are essential for the reliable operation and longevity of the systems cooled by water pumps.
Impellers are typically press-fit to a pump shaft and have a keyed coupling to prevent the impeller from slipping with respect to the pump shaft during use. Replacement of the impeller requires removal from the pump shaft by pulling the impeller off of the pump shaft. Traditional impeller pullers utilized in various industries (e.g., the marine industry) typically consist of metal tools with prongs or arms that engage the impeller during removal. While effective in some instances, these conventional pullers often pose the risk of damaging the shaft of the water pump or slipping with respect to the impeller during extraction. The rigidity of metal pullers, combined with the force required for removal, may result in tears or cracks in the impeller rubber, resulting in difficulty in removal of the impeller.
Conventional impeller removal tools may also lack versatility, making them incompatible with certain impeller designs or challenging to use in confined engine spaces. In one example, marine service personnel (engineers, mechanics, etc.) often require a wide variety of impeller puller types and sizes to address differing impeller installation configurations. Inaccessible impeller locations, especially in compact marine engine compartments, can impede the efficient application of conventional pullers, leading to time-consuming and labor-intensive maintenance procedures.
The foregoing aspects and many of the attendant advantages of the claimed subject matter will become more readily appreciated as the same become better understood by reference to the following detailed description, when taken in conjunction with the accompanying drawings, wherein:
The detailed description set forth above in connection with the appended drawings, where like numerals reference like elements, are intended as a description of various embodiments of the present disclosure and are not intended to represent the only embodiments. Each embodiment described in this disclosure is provided merely as an example or illustration and should not be construed as preferred or advantageous over other embodiments. The illustrative examples provided herein are not intended to be exhaustive or to limit the disclosure to the precise forms disclosed.
As will be described in more detail below, the present disclosure provides embodiments of an impeller removal tool assembly (“impeller puller”) that can be used to remove a press-fit impeller from a water pump shaft. Embodiments of the present disclosure are described herein with application examples related to the field of marine water pump maintenance and, more specifically, to an improved rubber impeller puller designed for efficient removal of rubber impellers from marine water pump assemblies. Embodiments disclosed herein address the challenges associated with existing impeller pullers, offering an enhanced solution that improves ease of use, minimizes potential damage to the pump shaft, water pump housing, and/or other components, and enhances overall efficiency in the maintenance process.
Although embodiments of the present disclosure may be described with reference to rubber impeller pullers for water pumps suitable for marine cooling systems, one skilled in the relevant art will appreciate that the disclosed embodiments are illustrative in nature and therefore should not be construed as limited to such an application. It should therefore be apparent that the disclosed technologies and methodologies have wide application, and therefore may be suitable for use with many types of water pumps, including different types of land, air, or marine vehicles, various engines, generators, and other equipment, and the like. As used herein, the term “water pump” is intended to include pumps configured to impart flow in any fluid or fluid mixture utilizing impellers with flexible vanes. In this regard, the impeller pullers of the present disclosure are suitable for use with impellers from pumps for cooling fluids (e.g., water, glycol-based coolant, water mixtures, etc.), high-and low-temperature fluids, viscous fluids (e.g., oils), delicate fluids, and/or slurry fluids having solid content. Such pumps are typically used in the oenological, food processing, chemical, cosmetic, and marine fields, and are applicable to the embodiments disclosed herein. Accordingly, the following descriptions and illustrations herein applying the embodiments to water pumps of marine cooling systems should not limit the scope of the claimed subject matter thereto.
The present disclosure provides examples of an impeller puller for removing water pump impellers press-fit onto pump shafts. Many water pumps are flexible vane pump assemblies having flexible material impellers made from, for example, natural rubber, synthetic rubber polymer (such as neoprene, nitrile, ethylene propylene diene monomer, etc.), silicone, etc. These flexible material impellers can be used in the water pump used to move fluid through a water pump by deforming (bending motion) of the flexible vanes. The flexibility of the vanes enables a tight seal to the internal housing, making the pump self-priming, while also permitting bi-directional operation. In these types of water pumps, the rubber impeller is driven by a pump shaft connected to a power source, such as a motor or mechanical power takeoff from the engine or transmission. The impeller can be connected to the pump shaft by friction in a press-fit coupling, with rotational torque of the pump shaft transferred by the friction fit and mechanically reinforced by interleaved splines or a key way feature.
Flexible vane impellers are typically constructed with a hub having the same material as the impeller vanes (e.g., rubber), and can include a reinforcing central cylinder, covered on the outwardly facing surface by the flexible material, to provide structure at the interface with the pump shaft. In the embodiments of the present disclosure, the puller includes arms having inwardly projecting teeth configured to grip against and/or pierce into the flexible material of the hub to provide a mechanical coupling to transfer the pulling forces to the impeller with respect to the pump shaft, urging the impeller hub off of the pump shaft. The puller can include a mechanical tightening system for the arms to provide increased mechanical leverage, the system having adjustable leverage strength by varying the bearing angle and/or thread pitch.
During maintenance of water pump systems, the replacement of the flexible impeller can be difficult due to typically confined spaces where the pump has been installed and the necessity of removing the impeller without damaging the shaft or housing of the water pump. Flexible impellers having larger diameters can often have a longer hub length, corresponding to greater surface area in contact with the shaft of the water pump. This relatively large surface area and other considerations (e.g., corrosion on the components) can increase the required force to remove the impeller from housing. To prevent binding, the impellers must be pulled off the pump shaft axially, as a skew in the removal can cause the impeller to become stuck on the shaft. Embodiments of the present disclosure are expected to address these and other needs in impeller removal tools.
The impeller pullers described herein can have arms having an angled surface configured to interface with an arm rotator bolt that allows a leveraged pressure of the arms on the impeller hub with a relatively low corresponding torque applied to the arm rotator bolt. As will be described below, with this leverage, a user of the impeller puller is able to generate a clamping force on hub of the impeller with a mechanical advantage. In some embodiments, the impeller puller can include a bearing surface to transfer the mechanical load to the angled surfaces while tightening the arm rotator bolt of the system, rather than having the rotating arm rotator bolt directly interface across the angled surfaces. The arms of the impeller puller include one or more teeth configured to pierce into the flexible material (e.g., rubber) of the hub of the impeller. As the mechanical load is applied through the arm rotator bolt into the arms, the teeth clamp inward toward the hub of the impeller. In this regard, as the arm rotator bolt is tightened, the arms rotate toward the impeller hub to engage the teeth into the flexible material. In some embodiments, the teeth have a profile that increases the grip with the flexible material as the axial force is applied to the impeller to remove it from the pump shaft. The configuration of the embodiments described herein allows removal of the impeller from the pump shaft by engagement of the teeth into the flexible material of the impeller hub.
In the disclosed embodiments, the arms can have any length, size, or profile. Although only two opposing arms are shown in the FIGURES, the impeller pullers of the present disclosure can be configured to have more than two arms, e.g., three arms, four arms, etc. The impeller pullers can be scaled in size and can be manufactured any suitable material, such as metal, composite, or a combination thereof. In some embodiments, the arm rotator bolt can include flats to use an external tool for mechanical leverage, such as a wrench. The angle and profile of the teeth, their spacing, and the number of teeth can vary depending on application configuration. In some embodiments, the bearing size and interfacing surface can be any shape to transmit rotation to the arms when tightening the arm rotator bolt.
The assembly 100 can further include an arm rotator bolt 120 configured to threadably engage an aperture of the central body 102 in a coaxial configuration, such that arm rotator bolt 120 moves axially with respect to the central body 102 when rotated within the central body 102. As shown in
As the arm rotator bolt 120 moves axially with respect to the central body 102, engagement with the first and second puller arms 110a and 110b causes the arms to rotate about the first and second pins 114a and 114b. The interface between the arm rotator bolt 120 and the first and second puller arms 110a and 110b can be separated by a bearing 130 positioned therebetween. The bearing 130 can have an arm interface surface 132 (e.g., as shown in the illustrated embodiment, a rounded surface), that interfaces with first and second angled ramp surfaces 116a and 116b on the upper portions of the first and second puller arms 110a and 110b, respectively, as the arm rotator bolt 120 moves axially with respect to the central body 102. The angled ramp surfaces 116a and 116b can be arranged at any angle or a compound angle, with a steeper angle (closer to vertical in the orientation shown in
Embodiments of the present disclosure can have any configuration of the angled ramp surfaces 116a and 116b. Accordingly, different size and material of impellers, or related tooth profile of the first and second puller arms 110a and 110b can require different ramp angles of the angled ramp surfaces 116a and 116b. In this regard, tougher impeller materials and/or more dull tooth profiles may require a steeper angle to provide greater mechanical leverage to engage the teeth with the impeller hub. Relatedly, softer impeller materials and/or sharper tooth profiles may benefit from a shallower angle to prevent the teeth from piercing too deep into the material, potentially impacting the enclosed impeller hub cylinder and/or the pump shaft. The illustrated embodiment of the teeth 112a and 112b shown in
The assembly 100 further includes a threaded central rod 140 coaxial with the arm rotator bolt 120 and the bearing 130, and having a tool engaging portion 142 (e.g., for a socket wrench, spanner, etc.) at a first end and an interface tip 144 at an opposite second end. During use of the assembly 100, as will be explained in greater detail below, once the teeth 112 of the first and second puller arms 110a and 110b are engaged into the flexible material of the impeller hub, the threaded central rod 140 can be rotated to press against the pump shaft to move all of the other components of the assembly 100 with respect to the pump shaft and the threaded central rod 140, imparting an axial force on the impeller with respect to the pump shaft and thereby removing the impeller from the pump shaft. In the embodiments disclosed herein, the first and second puller arms 110a and 110b are configured to rotate with respect to their corresponding first and second pins 114a and 114b at a similar rate during use to provide a centering effect of the threaded central rod 140, and resultingly aligning the interface tip 144 of the threaded central rod 140 with the shaft of the water pump.
In an example, the assembly 100 can be used according to the following procedure. The liquid (water, coolant, etc.) is drained from the cooling system and the cover is removed from the water pump housing to expose the impeller. The first and second puller arms 110a and 110b are initially adjusted by turning the arm rotator bolt 120 with respect to the central body 102. Once the first and second puller arms 110a and 110b are open wider than the diameter of the impeller hub portion, the assembly 100 is installed on the impeller by sliding the first and second puller arms 110a and 110b down the length of impeller until the central body 102 is near the pump housing. While holding the assembly 100 in place, the arm rotator bolt 120 is tightened toward the central body 102. During the tightening, the first and second puller arms 110a and 110b rotate about their corresponding pins 114 and drive the teeth 112 inward towards the impeller hub, engaging the flexible material. In some embodiments, the inward force is expected to cause the teeth 112a and 112b to pierce into the rubber material of the impeller hub. Next, the threaded central rod 140 is rotated with respect to the central body 102 toward the pump shaft until the interface tip 144 contacts the pump shaft, where continued rotation of the threaded central rod 140 exerts a pulling force on the impeller through the teeth 112 of the arms 110, removing the impeller from the pump shaft.
The above procedure will be described with respect to
In
In the foregoing description, specific details are set forth to provide a thorough understanding of exemplary embodiments of the present disclosure. It will be apparent to one skilled in the art, however, that the embodiments disclosed herein may be practiced without embodying all of the specific details. In some instances, well-known process steps have not been described in detail in order not to unnecessarily obscure various aspects of the present disclosure. Further, it will be appreciated that embodiments of the present disclosure may employ any combination of features described herein.
The present application may reference quantities and numbers. Unless specifically stated, such quantities and numbers are not to be considered restrictive, but exemplary of the possible quantities or numbers associated with the present application. Also in this regard, the present application may use the term “plurality” to reference a quantity or number. In this regard, the term “plurality” is meant to be any number that is more than one, for example, two, three, four, five, etc. The terms “about,” “approximately,” “near,” etc., mean plus or minus 10% of the stated value. For the purposes of the present disclosure, the phrase “at least one of A and B” is equivalent to “A and/or B” or vice versa, namely “A” alone, “B” alone, or “A and B.” Similarly, the phrase “at least one of A, B, and C,” for example, means (A), (B), (C), (A and B), (A and C), (B and C), or (A, B, and C), including all further possible permutations when greater than three elements are listed.
It should be noted that for purposes of this disclosure, terminology such as “upper,” “lower,” “vertical,” “horizontal,” “fore,” “aft,” “inner,” “outer,” “front,” “rear,” etc., should be construed as descriptive and not limiting the scope of the claimed subject matter. Further, the use of “including,” “comprising,” or “having” and variations thereof herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items. Unless limited otherwise, the terms “connected,” “coupled,” and “mounted” and variations thereof herein are used broadly and encompass direct and indirect connections, couplings, and mountings.
Throughout this specification, terms of art may be used. These terms are to take on their ordinary meaning in the art from which they come, unless specifically defined herein or the context of their use would clearly suggest otherwise.
The principles, representative embodiments, and modes of operation of the present disclosure have been described in the foregoing description. However, aspects of the present disclosure, which are intended to be protected, are not to be construed as limited to the particular embodiments disclosed. Further, the embodiments described herein are to be regarded as illustrative rather than restrictive. It will be appreciated that variations and changes may be made by others, and equivalents employed, without departing from the spirit of the present disclosure. Accordingly, it is expressly intended that all such variations, changes, and equivalents fall within the spirit and scope of the present disclosure as claimed.
| Number | Date | Country | |
|---|---|---|---|
| 63606325 | Dec 2023 | US |
