DE202013003691U1 - Cover for internal combustion engines - Google Patents

Abstract

Cover (300) for a front or a rear side of an internal combustion engine (110) comprising an upper lid portion (310), a lower lid portion (320) and a variable spacer (355), wherein after mounting the lid (300) on A combustion engine (110) overlaps a surface (370) of the upper lid portion (310) partially with a surface (380) of the lower lid portion (320) and the variable spacer (355) is spaced a distance (d) between the surface (370) of the upper lid portion (310) and the surface (380) of the lower lid portion (320) to eliminate.

Description

TECHNICAL AREA

The present disclosure relates to a lid suitable for internal combustion engines. More particularly, the invention relates to a control housing cover comprising two separate sections, an upper capable of covering at least a part of the engine cylinder head, and a lower one capable of covering at least a part of the engine block.

STATE OF THE ART

It is known that the front or rear of an internal combustion engine is sealed and covered to protect the internal parts, particularly belts, chains or gears, and to prevent the discharge of working fluids (mainly water and oil). Since the covering of the timing chain is one of the most important topics in this technical field, such covers are referred to as a control housing cover. According to the prior art, different solutions for fixing the cover to the engine are known.

In document US Pat. No. 6,591,801 B1 For example, a sealed lid is disclosed, such as an engine valve or toggle lid, which is secured to a motor with symmetrical grommets which hold the lid with equal compressive loads on the inside and outside of the lid. A sealing surface of the lid is positioned at a fixed distance from an opposing sealing surface of a cylinder head or other engine component. The gap is sealed with a liquid RTV sealant (room temperature vulcanizing) which is cured at room temperature in situ after the lid has been installed. The arrangement isolates the function of noise isolation from the sealing function performed by the RTV material so that the specifications of the sealing material and the noise insulating rubber grommet material can be varied as desired to perform their separate functions without interfering with each other.

In the document US 6,360,712 B1 a special mounting arrangement is described for an accessory to a motor, which is used with a pair of Einpressbuchsen in a pair of arms of the attachment and a guided through this single bolt. The arms of the mounting assembly are designed to over-spread the portions of an anchor member attached to the engine. A connecting bolt is inserted through a socket in one arm of the mounting assembly and through a passage in the anchor member, and next engaged with internal threads carried by the other sleeve, which in turn is carried by the other arm of the mounting assembly.

Finally, in the document US 5,129,375 discloses an auxiliary drive assembly for an internal combustion engine with belt driven overhead camshafts within a belt cover. On the engine, an additional mounting base is mounted within the belt cover having a bead portion which extends through the belt cover and which drives a pulley of an auxiliary drive.

Although not common, a solution adapted for internal combustion engines is the design of a control housing cover divided into two separate sections: an upper section covering at least part of the cylinder head and a lower section containing at least a part covering the engine block. The reasons for such a solution are easier assembly and maintenance. For example, a cover divided into two parts prevents the gearbox from being removed in view of the serviceability of the timing chain in order to be able to carry out work on the design of the timing chain. To prevent leaks, the upper and lower sections can not be reversed, but they should overlap at their common interfaces, the so-called T-joint area.

A possible solution for the attachment of a control housing cover of two separate parts is now that the upper portion is attached only to the cylinder head, while the lower portion is attached only to the engine block, without any common attachment points for connecting the upper and the lower portion. The mounting points are for manufacturing reasons and to reduce the connection opening close to the T-connection.

Regardless of this solution, T-joint areas are often affected by leakage problems. According to fault analysis and thermostructural analysis, this has the following reasons: different geometric tolerance of the parts (mostly engine block and cylinder head), mounting tolerances and different thermal expansions of the same parts. Such properties cause significant opening of the T-joint region, especially under operating conditions. A common fastening of the two cover sections in the T-connection region would not be sufficient, since such would cause an unacceptable thermal-structural stress in the cover sections.

There is thus a need for an improved version of a timing cover that not suffering from the problems listed above - leakage and mechanical stress - suffers.

A goal of an embodiment of the invention is to provide a new, reliable solution of the lid, whose separate upper and lower portions can ensure an adequate seal.

These objects are achieved with an engine cover and an internal combustion engine having the features described in the independent claims.

The dependent claims describe preferred and / or particularly advantageous aspects.

SUMMARY

An embodiment of the disclosure provides a lid for a front or a rear side of an internal combustion engine including a top lid portion, a bottom lid portion, and a variable spacer, wherein after the lid is mounted on the engine, a surface of the upper lid portion is a surface of the lower lid portion partially overlapped and the variable spacer is adapted to eliminate a distance between the surface of the upper lid portion and the surface of the lower lid portion.

An advantage of this embodiment is that the distance between the mutually partially overlapping surfaces of the upper and lower lid portion is not eliminated by the application of a load on the lid portions via fastening means, but thanks to a variable spacer which eliminates the distance, without the upper and lower cover section of a load suspend.

According to another embodiment, the variable spacing element comprises a threaded sleeve, and the upper or lower lid portion has a threaded opening into which the threaded sleeve is screwed.

Thus, the sleeve may be considered as a "movable part" of the upper lid portion (or alternatively the lower lid portion) which can be moved by screws towards the lower lid portion without subjecting the upper lid portion to mechanical stress.

According to one aspect of this embodiment, after the lid has been mounted on the internal combustion engine in an initial position where the distance reaches its maximum, the threaded sleeve is in contact with the upper or lower lid portion.

It follows that after the assembly of the upper and lower lid portions there is a controlled distance between them, or more preferably between the lower lid portion and the sleeve or alternatively between the upper lid portion and the sleeve.

According to another aspect of this embodiment, the threaded sleeve is in contact with the surface of the upper lid portion via a first surface of the threaded sleeve, the first surface being disposed perpendicular to the longitudinal axis of the threaded sleeve.

An advantage of this aspect is that the sleeve is preassembled on the upper lid portion, thereby reducing the risk of loss of parts.

According to another aspect of this embodiment, the threaded sleeve is after the mounting of the lid on the internal combustion engine and after the threaded sleeve has been screwed into the threaded opening of the upper lid portion in contact with the lower lid portion.

Thanks to this aspect, the elimination of the distance between the two surfaces of the upper and lower lid portions is due to the sliding of a threaded sleeve, which is screwed and therefore moved from an initial position (rest position) to an end position (operating position).

According to a further aspect of this embodiment, the threaded sleeve is in contact with the surface of the lower lid portion by means of a second surface of the threaded sleeve, the second surface being disposed perpendicular to the longitudinal axis of the threaded sleeve.

This aspect is due to the fact that the threaded sleeve, which is in contact with the lower lid portion, avoids any leakage from the T-connection portion of the lid.

According to a further aspect of this embodiment, after the cover has been mounted on the internal combustion engine and after the threaded sleeve has been screwed into the threaded opening of the lower cover section, the threaded sleeve is in contact with the upper cover section.

Thanks to this alternative aspect, the elimination of the distance between the two surfaces of the upper and lower lid portions occurs also due to the displacement of the threaded sleeve.

In another aspect, the maximum value of the distance is greater than a displacement equivalent to 1.5 turns of an automatic screwdriver.

An advantage of this aspect is that the screwing of the sleeve is compatible with the conditions of automatic screwdrivers.

In another aspect, after being mounted on the internal combustion engine, the upper and lower lid sections are connected to each other and to the internal combustion engine by means of a detachable connection.

An advantage of this aspect is the provision of a simple method of mounting the lid to the engine.

In another aspect, the detachable connection comprises a screw which is partially disposed in the threaded sleeve.

An advantage of this aspect is the improved packaging of the entire lid.

Another embodiment of the disclosure provides an internal combustion engine including a lid according to any one of the preceding embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

The various embodiments will now be described by way of example with reference to the accompanying drawings.

In 1 a control housing cover is shown with two sections - an upper and a lower cover section.

In 2 is the timing case cover the 1 shown mounted on an internal combustion engine.

3 is an exploded view of the control housing cover according to an embodiment of the invention.

In 4 an initial position of the lid sections is shown.

The 5 is an enlarged detail of the 4 ,

In 6 an end position of the lid sections is shown.

DETAILED DESCRIPTION OF THE DRAWINGS

According to a preferred embodiment of the invention is in 1 and 2 a lid 300 , in particular a control housing cover disclosed. As in 2 shown, this cover is advantageously used to the front or back of an internal combustion engine 110 seal and protect. The lid comprises two separate sections, an upper lid section 310 which is capable of covering at least part of a cylinder head (not shown) and a lower lid portion 320 , the at least part of the engine block 125 can cover. The underside of the upper lid section 310 and the top of the lower lid section 320 overlap each other along a surface, the so-called T-joint region. Due to different thermo-structural loads, leaks may occur in the T-connection area, which is why a suitable joint fastening must be implemented between the two cover sections.

As in 3 shown, has the upper lid section 310 after mounting the lid 300 at the engine a surface 370 that partially has a surface 380 of the lower lid section 320 overlaps. These may be arranged in the vicinity of the interface between the cylinder head and the engine block, but they could also be arranged at the level of the cylinder head or at the height of the engine block. The two lid sections 310 . 320 can according to the surfaces 370 . 380 via a detachable connection 335 be connected to an engine block.

Due to the conditions of the design and assembly process, the distance d between the partially overlapping surfaces could 370 . 380 the upper and lower lid sections are in the range of a few microns to almost 1 mm. Such a pitch bandwidth does not allow the use of a common attachment between the two lid portions, because the bending caused in at least one of the two lid portions would create undue structural stresses. At the same time, there is a high risk of oil leakage if no attachment is used.

In 4 - 6 is the mounting of the lid 300 shown on the engine. To allow joint attachment, the top lid section was made by adding a mounting base 375 with a controlled (in 5 recognizable) distance d between the surface 370 of the upper lid section 310 and the surface 380 of the lower lid section 320 after mounting the lid modified on the engine. The distance d is through a variable spacer 355 eliminated. In this solution, no lid portion is bent to eliminate the distance, but falls the variable spacer 355 the elimination of the gap and, consequently, the guarantee of the seal too.

Advantageously, the variable spacing element could 355 a threaded sleeve 360 include. The threaded sleeve 360 can in a threaded hole 315 of the upper lid section 310 (Or on the other hand in a threaded opening of the lower lid portion 320 ) and together with the upper lid section 310 (or according to the lower lid section 320 ) to be provided. The threaded sleeve 360 can be considered as a "moving part" of the upper lid section. It is moved by screws towards the lower lid portion, without exposing the upper lid portion of a mechanical load. Moreover, the fact that the sleeve is preassembled on the upper lid portion (or alternatively on the lower lid portion) reduces the risk of losing parts.

The threaded sleeve 360 is in an initial position (cf. 4 ) when the distance d has reached its maximum and if a first surface 361 the threaded sleeve in contact with the surface 370 of the mounting base 375 of the upper lid section 310 is (alternatively, the sleeve in contact with the lower lid portion 320 be). As in 5 shown, the threaded sleeve is an axisymmetric element on its longitudinal axis 363 , and the first surface 361 the sleeve 360 is a perpendicular to the longitudinal axis 363 arranged surface. When the threaded sleeve 360 in an end position (cf. 6 ) is screwed, there is a second surface 362 the threaded sleeve 360 in contact with the surface 380 of the lower lid section 320 (Alternatively, the sleeve may be in contact with the upper lid portion 310 be). Also the second surface 362 the sleeve 360 is perpendicular to the longitudinal axis 363 arranged.

Of course, after the distance between the two lid sections through the variable spacer 355 is eliminated, the cover sections themselves are mounted on the engine without prior selection, whereby the tolerance of the distance between the two lid sections should be reduced.

According to a preferred solution, the maximum value of the distance d is greater than an offset corresponding to 1.5 tube rotations of an automatic screwdriver. As a result, screwing in the sleeve meets the requirements for automatic screwdrivers. The automatic screwdriver, in fact, requires at least one complete revolution to achieve a target torque of about 3.5 Nm. Even if the threaded sleeve 360 theoretically no screwing torque required, so the automatic screwdriver but still reach a certain torque value, which is why the lid design has been implemented so that a torque of about 4 Nm is possible, which corresponds to 1.5 revolutions.

Once the sleeve the lower lid section 320 achieved, it is possible as a detachable connection 335 a screw 340 to attach the upper and lower lid sections to the engine. The screw is passed through the upper and lower lid sections and screwed into the motor, thus ensuring a seal without bending and tearing the upper and lower sections. A standard torque can be applied to the screw. The screw 340 Can be partially in the threaded sleeve 360 be arranged.

In summary, the present invention provides attachment of the upper and lower lid portions without bending effects, thereby creating a solid structure that prevents potential oil leakage in the T-junction due to thermo-structural openings.

While at least one exemplary embodiment has been illustrated in the foregoing summary and detailed description, it should be understood that there are a large number of variations thereto. It is also to be understood that the exemplary embodiment or exemplary embodiments are merely examples and are not intended to limit the scope, applicability, or configuration in any way. The foregoing summary and detailed description will much more readily provide those skilled in the art with practical guidance for implementing at least one example embodiment, always bearing in mind that various changes may be made to the operation and arrangement of the elements described in an exemplary embodiment without departing from the scope as set forth in the appended claims and their equivalents.

LIST OF REFERENCE NUMBERS

110

internal combustion engine

125

block

300

engine cover

310

Upper lid section

315

threaded opening

320

Lower lid section

335

Removable connection

340

screw

355

Variable spacer

360

threaded sleeve

361

First surface of the threaded sleeve

362

Second surface of the threaded sleeve

363

Longitudinal axis of the threaded sleeve

370

Surface of the upper lid section

375

Mounting base of the upper lid section

380

Surface of the lower lid section

d

Distance between a surface of the upper and a surface of the lower lid portion

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• US 6591801 B1 [0003]
• US 6360712 B1 [0004]
• US 5129375 [0005]

Claims (11)

Cover ( 300 ) for a front or a rear side of an internal combustion engine ( 110 ), which has an upper lid section ( 310 ), a lower lid portion ( 320 ) and a variable spacer element ( 355 ), wherein after the mounting of the lid ( 300 ) on the internal combustion engine ( 110 ) a surface ( 370 ) of the upper lid section ( 310 ) partially a surface ( 380 ) of the lower lid section ( 320 ) overlaps and the variable distance element ( 355 ), a distance (d) between the surface ( 370 ) of the upper lid section ( 310 ) and the surface ( 380 ) of the lower lid section ( 320 ) to eliminate. Lid according to claim 1, wherein the variable spacer element ( 355 ) a threaded sleeve ( 360 ) and wherein the upper lid portion ( 310 ) or the lower lid section ( 320 ) a threaded opening ( 315 ), in which the threaded sleeve ( 360 ) is screwed. Lid according to claim 2, wherein after assembly of the lid ( 300 ) on the internal combustion engine ( 110 ) in an initial position in which the distance (d) reaches its maximum value, the threaded sleeve ( 360 ) in contact with the upper lid portion ( 310 ) or with the lower lid section ( 320 ). Lid according to claim 3, wherein the threaded sleeve ( 360 ) by means of a first surface ( 361 ) of the threaded sleeve in contact with the surface ( 370 ) of the upper lid section ( 310 ), the first surface ( 361 ) perpendicular to Lid according to claim 2, wherein after assembly of the lid ( 300 ) on the internal combustion engine ( 110 ) and after the threaded sleeve ( 360 ) in the threaded opening ( 315 ) of the upper lid section ( 310 ) was screwed the threaded sleeve ( 360 ) in contact with the lower lid portion ( 320 ). Lid according to claim 5, wherein the threaded sleeve ( 360 ) by means of a second surface ( 362 ) of the threaded sleeve in contact with the surface ( 380 ) of the lower lid section ( 320 ), wherein the second surface is perpendicular to the longitudinal axis ( 363 ) of the threaded sleeve ( 360 ) is arranged. Lid according to claim 2, wherein after assembly of the lid ( 300 ) on the internal combustion engine ( 110 ) and after the threaded sleeve ( 360 ) in the threaded opening ( 315 ) of the lower lid section ( 320 ) was screwed the threaded sleeve ( 360 ) in contact with the upper lid portion ( 310 ). Lid according to one of the preceding claims, wherein the maximum value of the distance (d) is greater than an offset corresponding to 1.5 sleeve revolutions. Lid according to one of the preceding claims, wherein the upper ( 310 ) and lower ( 320 ) Cover section after mounting on the combustion engine ( 110 ) by means of a decreasing connection ( 335 ) with each other and with the internal combustion engine ( 110 ) get connected. Lid according to claim 8, wherein the detachable connection ( 335 ) a screw ( 340 ) partially in the threaded sleeve ( 360 ) is arranged. Internal combustion engine ( 110 ), which has a lid ( 300 ) according to one of the preceding claims

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