Patent ID: 12228225

DETAILED DESCRIPTION

To simplify the usage, improve the air flow behavior and anti-leak property of the tool30, a nipple-shaped assembly-free tool for maintenance of a gearbox in a vehicle is provided according to embodiments herein.

Three-dimension (3D) printing or additive manufacturing (AM) includes construction of a three-dimensional object from a computer-aided design (CAD) model or a digital 3D model. 3D printing or AM can be used for producing spare parts, prototypes etc. Products are manufactured layer by layer, close to their final shape, thereby reducing wastage. Materials used include, for example, metals, polymers, wood flour, biocompatible materials, sand and composites. 3D printing or AM paves a way for manufacturing on demand for many industries. Embodiments herein take the advantages of the 3D printing or AM. The nipple-shaped assembly-free tool according to embodiments herein consolidates three parts into one unit and can be additive manufactured by a single manufacturing process.

By manufacturing the whole tool as one unit and printing directly all parts and internal structures using 3D-printing machine during one single manufacturing process, the manufacturing process for the tool is simplified compared to that of the original tool and a decrease in price can be expected. Further, the tool does not need assembly process before usage, the usage of the tool is simplified, and the service maintenance time is therefore shortened. Due to the fact that the tool is directly 3D printed so there will be no change in inner channel diameter as exists in the original tool. This will improve the air flow stability during operation.

The nipple-shaped assembly-free tool according to embodiments herein can be applied in maintenance of gearboxes in heavy duty vehicles. Although the disclosure will be described with respect to a gearbox in a heavy duty truck, the disclosure is not restricted to this particular gearbox, but may also be used in other vehicles such as medium duty vehicles.

FIG.3(a)shows a perspective view of a tool100according to embodiments herein seen from a certain angle andFIG.3(b)shows a cross-section view of the tool100, where the internal structures are shown. The tool100has a nipple shape and can be used for maintenance of a gearbox in a vehicle.

As shown inFIGS.3(a) and (b), the tool100comprises a tubular body110extending in an axial A direction and having a first portion111with a first end115and a second portion112with a second end116. As can be seen fromFIG.3(b), an inner diameter D of the tubular body110is constant through the whole channel extending in the axial direction A of the tubular body110.

The tool100further comprises a cap nut120surrounding the first portion111of the tubular body110. The cap nut120is rotatable and axially translatable in relation to the tubular body110.

The tubular body110comprises a hose fitting structure130at the second portion112of the tubular body110. The hose fitting structure130may be any shapes or structures, e.g., the hose fitting structure130may comprise a first protrusion131and a second protrusion132around the tubular body110as shown inFIG.3(a) and (b). The hose fitting structure130may locate at any position within the second portion112of the tubular body110, e.g. 5-23 mm from the second end116of the tubular body110.

The hose fitting structure130is for connecting to a tube with compressed air via a hose, as shown inFIG.1, where the tool30is attached to a hose. The cap nut120is for connecting to the gearbox. The cap nut120and the tubular body110are retained as one unit such that they are non-detachable, or inseparable, or indivisible from each other. The tubular body110comprises a retaining structure140at the first portion111of the tubular body110for retaining the cap nut120and the tubular body110as one unit such that the cap nut120and the tubular body110are non-detachable from each other. The retaining structure140may locate at any position within the first portion111of the tubular body110, e.g. 4-9 mm from the first end115of the tubular body110. The retaining structure140may be any shape, e.g. an annular protrusion or bulge around the tubular body110as shown inFIG.3(b).

As shown inFIG.3(b), the cap nut120comprises internal threads at a first inside portion121of the cap nut120for connecting to the gearbox. The cap nut120further comprises a first contact surface122at a second inside portion123of the cap nut120. The tubular body110comprises a corresponding second contact surface113at a position114within the first portion111of the tubular body110. The first and second contact surfaces122,113are adapted to engage with each other when the tool100is in use and connected to the gearbox. The second contact surface113may be a surface of the retaining structure140.

To increase the contact surface area between the cap nut120and tubular body110, the first and second contact surfaces122,113may have several alternative embodiments having male-female fitting structures with any suitable shapes, such as protrusions and groves, convex and concave structures, threads etc., which are adapted to engage with each other.

According to some embodiments herein, one of the first and second contact surfaces122,113may comprise at least one contact protrusion and the other of the first and second contact surfaces122,113may comprise a corresponding at least one groove. The at least one contact protrusion and the at least one groove being adapted to engage with each other, as shown inFIG.3(c), where the first contact surface122comprises one or more grooves, and the second contact surfaces113comprises one or more protrusions.

According to some embodiments herein, one of the first and second contact surfaces122,113may comprise at least one convex structure and the other of the first and second contact surfaces122,113may comprise a corresponding at least one concave structure. The at least one convex structure and the at least one concave structure being adapted to engage with each other.

According to some embodiments herein, the first and second contact surfaces122,113may comprise thread which are adapted to contact and fit to each other.

When using the tool100, the cup nut120is connected to a union e.g. the elbow union of the gearbox by rotating the cup nut120. Although there may be slightly friction during the rotation due to the male-female fitting structures of the first and second contact surfaces122,113, the first and second contact surfaces122,113are engaged or fitted with each other when the cup nut120has been connected to the union at the end of the rotation. The contact surface area between the cap nut120and tubular body110is increased due to male-female fitting structures compared to smooth surfaces on both the first and second contact surfaces122,113. Therefore, with any one of these alternative embodiments described above implemented to the first and second contact surfaces122,113, the contact surface area between the cap nut120and tubular body110will be increased such that a better air-tight function or better anti-leak property for the tool100is ensured and achieved compared to the original tool30.

To decrease the weight and material of the tool, any one or both of the cap nut120and hose fitting structure130may have a hollow structure.

To increase the strength of the cap nut120and hose fitting structure130, the cap nut120and hose fitting structure130may comprise one or more strengthening ribs124,134, as shown inFIG.4.

According to some embodiments herein, the tool100may be made of stainless steel, tool steel or titanium alloy according to embodiments herein.

The tool100may be manufactured by additive manufacturing, i.e. 3D printing.FIG.5shows a flow chart of a method500for manufacturing the tool100. The method500comprises the following actions.

Action510

Printing the whole tool100by using a 3D-printing machine on a building plate starting from the first end115of the tubular body110and the first end125of the cap nut120and continuing up to the second end116of the tubular body110. The tubular body110and the cap nut120are 3D-printed as one unit during a single manufacturing process.

During the same single manufacturing process, the optional internal threads121of the cap nut120, the optional hose fitting structure130, the optional retaining structure140i.e. the protrusion structure140, of the tubular body110, the optional contact surfaces122,113with fitting structures, such as protrusions and corresponding grooves, convex and concave structures, threads etc., and/or the optional strengthening ribs124,134are directly 3D-printed such that the whole tool100is 3D-printed as one unit during one single manufacturing process.

As can be seen fromFIG.3(b), important face-down surfaces, e.g. surface117of the protrusion structure140, surfaces118,119of the hose fitting structure130on the tubular body110, the first contact surface122of the cup nut120etc., all have an angle such that they can be printed layer by layer without extra support structures during 3D printing.

Action520

Separating the whole tool100as one unit or a single piece from the building plate. The tool is ready to use without any post processing and assembly process.

FIG.6is a simplified cross-section view of an example 3D printing machine600, which may be used to manufacture the tool100by Selective Laser Melting (SLM) process. During the SLM process, a product is formed by selectively melting successive layers of powder by the interaction of a laser beam. Upon irradiation, the powder material is heated and, if sufficient power is applied, melts and forms a liquid pool. Afterwards, the molten pool solidifies and cools down quickly, and the consolidated material starts to form the product. After the cross-section of a layer is scanned, the building platform is lowered by an amount equal to the layer thickness and a new layer of powder is deposited. This process is repeated until the product is completed.

This layer-by-layer process was first used to produce prototypes, but the trend is towards direct manufacture of components because of its ability to net-shape manufacture complex structures from a CAD model and a wide range of materials without the need of expensive tooling and machining so that the delay between design and manufacture is minimised.

As shown inFIG.6, during the process, metal powder610in a dispenser plate620is heated close to its melting point and spread by a power recoater630on a building plate640. A scanning head650connected to a laser generator660draws or scans a cross section of a part, e.g. the tool100, into the powder material, i.e. the cross section of the first end115of the tubular body110and the first end125of the cap nut120are formed by the laser beam. After the cross-section of a layer is scanned, the building plate640is lowered corresponding to one layer thickness which is approximately 0.1 mm, after which the process is repeated until the 3D tool100is completed. A collecting plate670is used for collecting the rest of un-melted metal powder.

As the finishing is done together with the SLM, no additional finishing is required except from removing un-melted metal powder. This process produces objects with very good finish.

Another advantage of this process is that the powder is melted only locally by the laser and the rest of the powder can be recycled for further fabrication. The SLM may be used to selectively melt nickel-based superalloys, Ti-based alloys, Al-based alloys and Nb-based alloys to fabricate components and structures for automobile and aerospace application.

To summarize, advantages and improved performances of the tool100according to embodiments herein may include and not limited to the following:Providing a single piece assembly-free tool100manufactured by 3D printing with metal, e.g. stainless steel, tool steel or titanium alloy. By making the tool assembly-free, the service maintenance time will be shortened.The tool100is designed in a way that it can be 3D printed as one unit or one piece. The structures and shapes of the tool100is configured in such a way that there will be no need for support structure during printing which minimizes the post processing and reduces the cost.The tool100has simplified manufacturing process which avoids manufacturing different parts, i.e. three parts of the original tool can be printed as one unit during a single 3D printing process. No assembly structures such as screw or threads are needed as the original tool, e.g. the first and third parts of the original tool are integrated to one piece, i.e. the tubular body110. Due to the fact that the whole tool100is directly 3D printed so there will be no change in inner channel diameter as exists in the original tool. This will improve the air flow stability during operation.The male-female fitting structures on the contact surfaces of the tubular body110and the cap nut120increase the contact surface area thereby ensure better anti-leak property for the tool100. This kind of internal structures can be directly 3D printed and may not otherwise be achieved by conventional manufacturing.The new tool100has a light-weighted structure, i.e. hollow structure with or without strengthening ribs which lights the weight more than 20% of the original tool. The cost for 3D printing the tool100may be reduced as smaller volume of metal will be used compared to the original tool.After printing, the whole tool100can come off the build plate as one piece. The outer sub-part, i.e. the cup nut120can rotate with respect to the inner pipe, i.e. the tubular body110. The original function of the original tool is fully filled by the new tool100.The threads121inside the cup nut120cannot be manufactured by any conventional methods since there will be no space for a threading tool. The threads instead are directly 3D printed based on the concept that the whole tool is manufactured as one piece.

It is to be understood that the present invention is not limited to the embodiments described above and illustrated in the drawings; rather, the skilled person will recognize that many changes and modifications may be made within the scope of the appended claims.