GB2562786A

GB2562786A - Method of attaching a first component to a second component, component for use with the method, components joined using the method, and sump comprising

Info

Publication number: GB2562786A
Application number: GB1708423.7A
Authority: GB
Inventors: John Desmond Alexander; Johnson Jack
Original assignee: Jaguar Land Rover Ltd
Current assignee: Jaguar Land Rover Ltd
Priority date: 2017-05-26
Filing date: 2017-05-26
Publication date: 2018-11-28
Anticipated expiration: 2037-05-26
Also published as: GB2562786B; GB201708423D0

Abstract

A method of attaching a first component 100 comprising at least a first opening 104 to a second component 102 comprising at least a second opening 106 where the second component 102 includes a compression limiter 112. The first and second components 100, 102 are positioned in an overlapping relationship, such that the first and second openings 104, 106 at least partly overlap and the compression limiter 112 and a threaded fastener 114 (see figure 1B) extend at least partly through the first opening 104. As the threaded fastener is tightened, an axial compressive force causes the compression limiter 112 to deform radially to engage an internal edge of the first opening 104, thereby to attach the first component 100 to the second component 102. The first and second components 100, 102 may be formed from materials with different coefficients of thermal expansion. The first component 100 may be a polymeric sump liner and the second component 102 may be a sump frame.

Description

METHOD OF ATTACHING A FIRST COMPONENT TO A SECOND COMPONENT, COMPONENT FOR USE WITH THE METHOD, COMPONENTS JOINED USING THE METHOD, AND SUMP COMPRISING FIRST AND SECOND SUMP COMPONENTS

TECHNICAL FIELD

The present disclosure relates to attaching a first component to a second component.

The invention has been developed particularly, but not exclusively, for joining automotive components to each other, such as parts of a two-part sump comprising first and second components formed from different materials having different coefficients of thermal expansion. It will be appreciated, however, that the invention and embodiments may be applied in other fields and for different applications.

Aspects of the invention relate to a method of attaching a first component to a second component, a component for use with the method, a component for use with the method, and a vehicle comprising first and second components attached in accordance with the method.

BACKGROUND

In general, engine sumps are unitary components. In the past, sumps were most commonly stamped from a sheet material such as steel, but more recently have also been cast, forged, machined or otherwise formed from a material such as aluminium alloy.

A novel, unpublished approach to sump manufacture is to provide separate frame and liner components. The frame may be formed from a relatively strong material such as an aluminium alloy, while the liner may be formed from a polymeric material such as glassreinforced nylon. Because engine lubricant is retained in the liner, the frame may be formed in such a way that it is stronger only in places where strength is needed. For example, the frame may not be continuous over the whole surface of the liner. This approach allows an advantageous combination of strength and weight reduction, which may be useful where attempts are being made to reduce overall vehicle weight while retaining sump strength, which may be useful if the sump is to perform a structural role.

A difficulty faced by using such different materials is a relative disparity that may exist in their physical characteristics. For example, aluminium alloys typically have a far higher coefficient of thermal expansion than glass-reinforced nylon. The different materials may also have different manufacturing tolerances that make it difficult to accurately produce articles with, for example, identically sized openings for fixtures that align perfectly when the components are assembled at or before the time of their installation onto an engine.

Similar issues may apply in other scenarios where it is desired to join overlapping components.

Although at least some of the disadvantages above may be exacerbated when the first and second components have different coefficients of thermal expansion, it will be appreciated that even where the coefficients are similar, it may still be desirable to provide a way of attaching such components to each other in an efficient manner, especially where a hole in one component may not be identical in size to the outer diameter of a corresponding compression limiter on the other component.

It would be desirable to attach first and second components, such as components of a twopart sump, to each other in such a way as to overcome these and/or other disadvantages.

SUMMARY OF THE INVENTION

Aspects and embodiments of the invention provide a method of attaching a first component to a second component, a component for use with the method, a component for use with the method, and a vehicle comprising first and second components attached in accordance with the method, as claimed in the appended claims

According to an aspect of the invention, there is provided a method of attaching a first component to a second component, the first component comprising at least a first opening, and the second component comprising at least a second opening, the second component comprising a compression limiter, the method comprising:

positioning the first component and the second component in an overlapping relationship, such that the first and second openings at least partly overlap, and the compression limiter and a threaded fastener extend at least partly through the first and second openings;

tightening the threaded fastener, such that as the fastener is tightened, it places an axial compressive force on the compression limiter, in response to which at least a portion of the compression limiter deforms radially to engage an internal edge of the first opening, thereby to attach the first component to the second component.

The deformation of the compression limiter may include plastic deformation, such that the first component remains attached to the second component when the threaded fastener is subsequently loosened.

The first component may be made of a first material and the second component may be made of a second material different to the first material.

The first material may have a different coefficient of thermal expansion to the second material.

The first material may be polymeric. The first material may be a glass-reinforced plastics material.

The second material may be metallic.The second material may be aluminium or an aluminium alloy.

The first component may be a polymeric sump liner.

The second component may be a structural frame for supporting a sump liner.

The compression limiter may be formed integrally with the structural frame.

According to another aspect of the invention, there is provided a component for use with any other aspect ofthe invention, the component including the compression limiter.

The component may be a sump component.

The compression limiter may comprise a boss encircling the second opening.

According to another aspect of the invention, there is provided a first component attached to a second component in accordance with any other aspect of the invention.

According to another aspect of the invention, there is provided a sump comprising first and second components attached to each other in accordance with any other aspect of the invention.

According to another aspect of the invention, there is provided an engine comprising:

an engine block; and a sump according to any other aspect of the invention, the sump being attached to the engine block by way of the threaded fastener.

According to another aspect of the invention, there is provided a vehicle comprising first and second components attached to each other in accordance with any other aspect of the invention.

The first and second components may form part of a sump or a rocker cover.

Within the scope of this application it is expressly intended that the various aspects, embodiments, examples and alternatives set out in the preceding paragraphs, in the claims and/or in the following description and drawings, and in particular the individual features thereof, may be taken independently or in any combination. That is, all embodiments and/or features of any embodiment can be combined in any way and/or combination, unless such features are incompatible. The applicant reserves the right to change any originally filed claim or file any new claim accordingly, including the right to amend any originally filed claim to depend from and/or incorporate any feature of any other claim although not originally claimed in that manner.

BRIEF DESCRIPTION OF THE DRAWINGS

One or more embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings, in which:

Figs. 1A to 1D are sectional views of showing the attachment of a first component to a second component, in accordance with an embodiment of the invention;

Fig 2 is a sectional view of an alternative compression limiter for use with embodiments of the invention;

Fig 3 is a sectional view of another alternative compression limiter for use with embodiments of the invention;

Fig. 4 is perspective view of a sump comprising first and second components, the second component according to a further embodiment of the invention;

Fig. 5 is a detailed perspective view of a portion of the sump of Fig. 4;

Fig. 6 is a detailed perspective view of a portion of the second component of the sump of Fig. 4;

Fig. 7 is a detailed sectional view through part of the sump of Figs 4 to 6, showing the threaded fastener after tightening;

Fig. 8 is a side elevation of a vehicle comprising components attached to each other in accordance with an embodiment of the invention; and

Fig. 9 is a flowchart of a method of attaching a first component to a second component, according to yet another embodiment of the invention.

Throughout the description, similar elements across embodiments are indicated with like reference signs.

DETAILED DESCRIPTION

Referring to the drawings, Figs 1A to 1D show the attachment of a first sheet 100 to a second sheet 102. In this embodiment, the first sheet 100 and second sheet 102 are formed from different materials, and more particularly, from materials having different coefficients of thermal expansion. For example, the first sheet 100 may be formed from a composite polymeric material, such as glass-reinforced nylon, and the second sheet 102 may be formed from a metal, such as an aluminium alloy. Aluminium alloy has a greater coefficient of thermal expansion than that of glass-reinforced nylon. The first sheet 100 has a first opening 104. The second sheet 102 has a second opening 106.

The second sheet 102 includes an integral compression limiter in the form of a boss 112 that encircles the second opening 106. The boss 112 may be formed integrally as part of the manufacturing process of the second sheet 102, or may be at least partly formed by way of machining processes following initial moulding, forging or forming of the second sheet 102.

The boss 112 extends axially away from the second sheet 102 by a distance D1 that is greater than the thickness D2 of the first sheet. The external diameter of the boss 112 is smaller than an internal diameter of the first opening 104. The larger size of the first opening 104 relative to the outer diameter of the boss 112 means that there is some tolerance in the initial positioning of the first sheet 100 relative to the second sheet 102 while still allowing relatively accurate alignment of the second opening 106 with the threaded bore 110. The tolerance in the initial positioning of the first sheet 100 may be required due to, for example, differences in manufacturing tolerances applicable to the first sheet 100 and the second sheet 102.

To attach the first sheet 100 to the second sheet 102, they are positioned in an overlapping relationship, as shown in Fig. 1A. In this embodiment, the first sheet 100 and the second sheet 102 are also to be attached to a substrate 108, which has a threaded bore 110. The substrate 108 may be formed from, for example, an aluminium alloy. The first opening 104 and the second opening 106 at least partly overlap with each other. In this embodiment, the first opening 104 and the second opening 106 are positioned so as also overlap with the threaded bore 110, as shown in Fig. 1A.

As shown in Fig. 1B, when the first sheet 100 and second sheet 102 are placed in an overlapping relationship with each other, the boss 112 extends through the first opening 104 and engages a surface of the substrate 108 adjacent the threaded bore 110. A threaded fastener in the form of a bolt 114 is inserted through the first opening 104 and second opening 106, and then screwed into the threaded bore 110. An optional washer 116 is used to help distribute axial force from the bolt 114 to the second sheet 102 and boss 112.

As the bolt 114 is initially tightened, the boss 112 is urged into contact with the surface of the substrate 108. Further tightening of the bolt 114 causes an increasing axial compressive force to be applied to the boss 112.

As shown in Fig. 1C, further tightening of the bolt 114 causes the boss 112 to deform radially, such that a radially outer surface 118 of the boss 112 engages an internal edge of the first opening 104. The result is attachment of the first sheet 100 to the second sheet 102, with both the first and second sheets being attached to the substrate 108.

In the embodiment illustrated, tightening the bolt 114 to a predetermined torque results in the deformation comprising a plastic deformation component. Accordingly, if the bolt 114 is subsequently loosened or even removed as shown in Fig. 1D, the boss 112 remains deformed sufficiently that the first sheet 100 and second sheet 102 remain attached to each other. This approach has the advantage of effectively locking the first and second sheets together in a relatively permanent way, meaning that they can be removed and reattached to the substrate 108 as a unit, without the need to realign the first and second sheets upon reattachment.

It is not strictly necessary for D1 to be greater than D2. If the first component is sufficiently compressible, D1 may be the same size as D2, or even smaller than D2, as long as sufficient axial force can be generated by the threaded fastener to cause the required deformation of the boss 112.

The embodiment of Figs 1A to 1D shows the compression limiter (i.e., boss 112) as an integral part of the second sheet 102. In other embodiments, the compression limiter may be an integral part of the first sheet 100.

Alternatively, or in addition, the compression limiter may be configured or formed so as to encourage the desired deformation. For example, as shown in Fig. 2, one or more grooves 260 or recesses within the area to be deformed may encourage the required deformation. Alternatively, or in addition, the thickness of the wall of the compression limiter may vary along its length, being thinner where deformation is desired and thicker where deformation is discouraged. For example, as shown in Fig. 3, deformation takes place preferentially along the thinner section 262.

The compression limiter may be designed to deform mainly or solely in a radially outward direction. This may be useful where it is desirable that the threaded fastener be removeable. Allowing deformation (and particularly plastic deformation) in a radially inward direction may risk binding of the threaded fastener by the deformed compression limiter, and accordingly may make it more difficult to reattach the first and second sheets to the substrate. In certain embodiments, however, this may be acceptable.

The deformation may take place at other axial positions along the compression limiter. For example, radially outward deformation of the compression limiter at end furthest from the first second sheet may assist in preventing the first sheet from being removed from the second sheet. Deformation of the compression limiter more axially central to the first sheet, or along most of the length of the compression limiter, may assist in positively laterally locating the first and second sheets relative to each other.

Although it is desirable in some embodiments that the compression limiter be continuous, in other embodiments it may be acceptable for the compression limiter to include one or more discontinuities. For example, instead of a continuous boss 112, the compression limiter may take the form of a series of raised ribs or lands around the second opening 106. The ribs may be elongate or relatively compact in plan. The lands may be any suitable shape in plan, such as circular, oval or polygonal. The sectional shape or configuration of any rib or land may be selected so as to provide a desired deformation pattern, as described above in relation to the boss 112.

Turning to Figs 4 to 7, there is shown an embodiment applied to a two-piece sump 126 that is attached to an engine 128 (see Fig. 7). The sump 126 includes a first component in the form of a sump liner 130 and a second component in the form of a structural frame 132 for supporting the sump liner 130. The sump liner 130 may be formed from, for example, a composite polymeric material, such as glass-reinforced nylon. The structural frame 132 may be formed from, for example, an aluminium alloy. In an embodiment, the structural frame 132 is grade LM 24 high pressure die cast (HPDC) aluminium.

The sump liner 130 is designed to retain a volume of oil for the engine 128. The structural frame 132 supports the sump liner 130 and reinforces it where required. The structural frame 132 need not be continuous over the whole of the sump liner 130, which may reduce the amount of material required for the structural frame 132.

The structural frame 132 includes an outwardly extending flange 134 extending around its top edge. The flange 134 includes second openings in the form of through holes 136. Each through-hole 136 is surrounded by an upwardly extending boss 138, similar to boss 112 described above.

The polymeric sump liner 130 also includes an outwardly extending flange 140 extending around its top edge. The outwardly extending flange 140 of the sump liner 130 includes first openings in the form of through holes 142. The through holes 142 are large enough to allow insertion of the corresponding bosses 138.

The two-part sump 126 is designed to be attached to the engine 128, and more particularly to the bottom of engine block 129. Prior to the sump 126 being attached to the engine 128, the sump liner 130 is positioned within the structural frame 132, such that the outwardly extending flange 140 of the sump liner overlaps the outwardly extending flange 134 of the structural frame 132. The through holes 142 are positioned to overlap the through holes 136. Due to differences in manufacturing tolerances, it may be difficult to ensure that the through holes 142 perfectly align with the corresponding bosses 112. In addition, the different coefficients of thermal expansion of the sump liner 130 and the structural frame 132 make it desirable that the sump liner 130 and structural frame 132 are tightly joined to each other, to prevent rubbing between the two components during thermal cycling of the engine 128 and sump 126.

The sump 126 is then positioned relative to the engine 128. Threaded fasteners in the form of bolts 144 are inserted through the overlapping through holes 136 and 142, and then screwed into a threaded bore 146 formed within the engine block 129. As the bolts 144 are initially tightened, the bosses 138 are urged into contact with the engine block 129. Tightening of the bolts 144 causes an increasing axial compressive force to be applied to the bosses 138. Further tightening of the bolts 144 causes the bosses 138 to deform radially, such that an outer surface of each boss 138 engages an internal edge of its corresponding through hole 142. The result is attachment of the sump liner 130 to the structural frame 132, and of the sump 126 as a whole to the engine 128.

In the embodiment illustrated in Figs 4 to 7, tightening the bolts 144 to a predetermined torque results in the deformation comprising a plastic deformation component. Accordingly, if the bolt 144 is subsequently loosened or even removed, the bosses 138 remain deformed sufficiently that the sump liner 130 and structural frame 132 remain attached to each other. This approach has the advantage of effectively locking the sump liner 130 and structural frame 132 together in a relatively permanent way, meaning that the sump 126 can be removed in one piece from the engine 128, and subsequently reattached thereto, without the need to realign the sump liner 130 and structural frame 132 upon reattachment.

Turning to Fig. 8, in another embodiment, a vehicle in the form of a car 254 comprises first and second components attached to each other in accordance with any of the embodiments above. For example, the car 254 may include a two-part sump 126 as described above. Alternatively, or in addition, the car 254 may include one or more other embodiments. For example, the car 254 may include a structural rocker cover frame (not shown) with a plastic liner (not shown), mounted to the head of the car’s engine (not shown). The rocker cover frame and plastic liner would experience thermal expansion issues similar to those of the above-described sump 126.

Turning to Fig. 9, there is shown a method of attaching a first component to a second component. The first and second components may be formed from different materials, which in turn may have different coefficients of thermal expansion. The first and second components may be sub-components of an automotive component such as a sump or rocker cover. The first component comprises at least a first opening, and the second component comprises at least a second opening.

The method comprises positioning 256 the first component and the second component in an overlapping relationship, such that the first and second openings at least partly overlap and a compression limiter and a threaded fastener extend at least partly through the first and second openings.

Next, a threaded fastener is tightened 258 into a threaded bore. As the fastener is tightened, it places an axial compressive force on the compression limiter, in response to which at least a portion of the compression limiter deforms radially to engage an internal edge of at least one of the first and second openings. This attaches the first component to the second component.

The first and second components, the compression limiter, and the threaded fastener may correspond, for example, with any of the corresponding above-described elements.

Although the above embodiments describe the attachment of a first component to a second component, it will be appreciated that more than two components may be joined together by way of this invention. For example, one or more additional components may be positioned between the first and second components.

Some or all of the outer surface of the compression limiter may be knurled, grooved, or otherwise patterned to increase grip between the deformed portion of the compression limiter and the adjacent first and/or second component.

Although the invention has been described reference to a number of specific non-exhaustive and non-limiting embodiments, the skilled person will appreciate that the invention may be embodied in many other forms.

Claims

1. A method of attaching a first component to a second component, the first component comprising at least a first opening, and the second component comprising at least a second opening, the second component comprising a compression limiter, the method comprising:

2. The method of claim 1, wherein the deformation of the compression limiter includes plastic deformation, such that the first component remains attached to the second component when the threaded fastener is subsequently loosened.

3. The method of any preceding claim, wherein the first component is made of a first material and the second component is made of a second material different to the first material.

4. The method of claim 3, wherein the first material has a different coefficient of thermal expansion to the second material.

5. The method of claim 4, wherein the first material is polymeric and the second material is metallic.

6. The method of claim 5, wherein the first material is a glass-reinforced plastics material.

7. The method of claim 5 or 6, wherein the second material is aluminium or an aluminium alloy.

8. The method of any preceding claim, wherein the first component is a polymeric sump liner.

9. The method of any preceding claim, wherein the second component is a structural frame for supporting a sump liner.

10. The method of claim 9, wherein the compression limiter is formed integrally with the structural frame.

11. A component for use with the method of any preceding claim, the component including the compression limiter.

12. The component of claim 11, wherein the component is a sump component.

13. The component of any preceding claim, wherein the compression limiter comprises a boss encircling the second opening.

14. A first component attached to a second component in accordance with the method of claim 2, or any one of claims 3 to 10 when dependent on claim 2.

15. A sump comprising first and second components attached to each other according to claim 14.

16. An engine comprising:

an engine block; and a sump according to claim 15, the sump being attached to the engine block by way of the threaded fastener.

17. A vehicle comprising first and second components attached to each other in accordance with the method of any one of claims 1 to 10.

18. The vehicle of claim 17, wherein the first and second components form part of a sump or a rocker cover.