MOTOR VEHICLE WITH HEAT ENGINE WITH IMPROVED LUBRICATION OF THE PERIPHERALS DRIVEN BY THE CAMSHAFT

Abstract

The invention relates to a motor vehicle comprising a heat engine itself comprising at least one camshaft (200) guided in rotation about an axis of rotation (D) by at least one support bearing (210) and carrying at least one cam (220) for controlling a radial movement, in a direction perpendicular to said axis of rotation (D), of at least one actuator (230), said at least one camshaft (200) being at least locally hollow and arranged to contain a lubricant, and comprising at least one end cap (240) arranged to control the radial outlet and prevent the axial outlet of said lubricant from said at least one camshaft (200), which end cap (240) comprises at least one lubricant circulation channel (250) arranged to allow the circulation of lubricant between at least one inlet orifice (260) and an outlet orifice (270) radial and calibrated in line with a said actuator (230). Figure 2.

Description

Title of the invention: MOTOR VEHICLE WITH HEAT ENGINE WITH IMPROVED LUBRICATION OF THE PERIPHERALS DRIVEN BY THE CAMSHAFT

[0001] The invention relates to a motor vehicle comprising at least one heat engine itself comprising at least one camshaft guided in rotation about an axis of rotation by at least one support bearing and carrying at least one cam for controlling a radial movement, in a direction perpendicular to said axis of rotation, of at least one actuator, said at least one camshaft being at least locally hollow and arranged to contain a lubricant, and comprising at least one end plug arranged to control the radial outlet and prevent the axial outlet of said lubricant from said at least one camshaft.

[0002] The invention relates to the field of motor vehicles with a thermal engine with a camshaft, and the lubrication of engine accessories controlled by a camshaft, or close to a camshaft.

[0003] The invention relates to the problem of lubricating the peripherals driven by the camshaft on an internal combustion engine.

[0004] This lubrication is commonly carried out by a plain bearing or lubricant mist in the environment of the contact between the high pressure fuel pump cam and the pump tappet roller.

[0005] However, this lubrication proves to be insufficiently directed to satisfy the need for contact between the high pressure fuel pump cam and the pump tappet roller.

[0006] The objective of the present invention is to overcome these drawbacks by proposing to use a plug at the end of the camshaft, by arranging it in a suitable manner to bring the lubricant, in particular oil, from the camshaft bearing to the high pressure petrol pump cam and the roller of its tappet, using a circulation of lubricant internal to the camshaft, imposed by circulation channels arranged at least in this plug.

[0007] This arrangement of the camshaft according to the invention makes it possible to better direct the lubrication towards the contact zone between the roller of the high pressure petrol pump tappet and its cam on the camshaft, as well as in the roller and its needles.

[0008] The invention allows the creation of a circulation of lubricant internal to the camshaft by using an already existing plug, modified with some evolutions of definition allowing the passage of lubricant from the camshaft bearing to the injection pump control cam area.

[0009] To achieve this objective, the invention proposes a motor vehicle comprising at least one heat engine itself comprising at least one camshaft guided in rotation about an axis of rotation by at least one support bearing and carrying at least one cam for controlling a radial movement, in a direction perpendicular to said axis of rotation, of at least one actuator, said at least one camshaft being at least locally hollow and arranged to contain a lubricant, and comprising at least one end plug arranged to control the radial outlet and prevent the axial outlet of said lubricant from said at least one camshaft.

[0010] According to the invention, said at least one end plug comprises at least one lubricant circulation channel arranged to allow the circulation of lubricant between at least one inlet orifice and a radial and calibrated outlet orifice in line with a said actuator.

[0011] Thanks to the invention, it is possible, without heavy modification, to deliver lubricant exactly where needed.

[0012] Advantageously, said at least one inlet orifice is provided at the level of a said support bearing.

[0013] Thus the lubricant supply uses existing components, and avoids the use of added components.

[0014] Advantageously, said at least one lubricant circulation channel comprises a first annular chamber limited between surfaces of said at least one end plug and at least one sealing surface comprised in a bore comprised in said at least one camshaft and / or comprised in said at least one end plug and / or comprised in a sealing component carried by said bore or said end plug, said first annular chamber being arranged to distribute lubricant to a second lateral chamber opening onto said outlet orifice.

[0015] It is thus easy to separate a first chamber collecting the lubricant at the inlet, and a second chamber containing the lubricant to be delivered to the peripheral driven by the camshaft.

[0016] More particularly, said bore comprises a said sealing surface.

[0017] The bore can thus include a shoulder forming a sealing surface.

[0018] More particularly, said end cap comprises a said sealing surface.

[0019] It is more economical to adapt the end cap than the camshaft itself, for example by choosing a composite cap with a sealing area provided at an elastic material.

[0020] More particularly, said bore or said end plug carries a said sealing component which is a seal interposed under pressure between said bore and said at least one end cap.

[0021] It is thus easy to modify an existing end cap to make it an efficient lubricant dispenser. This arrangement is particularly economical.

[0022] Advantageously, said second lateral chamber is limited, on the one hand by said bore of said at least one camshaft, and on the other hand by a flat formed in said at least one end plug in the direction of said axis of rotation.

[0023] Machining the end cap is then very simple.

[0024] Advantageously, said sealing gasket is housed in a groove that said at least one end plug comprises.

[0025] The distribution and sealing functions are thus, very simply, combined at the end cap.

[0026] Advantageously, said seal is located at the level of a said support bearing.

[0027] The bearing thus provides its rigidity, and prevents deformation of the plug and the seal that it contains.

[0028] Advantageously, a said actuator is a high pressure fuel pump tappet roller, and a said outlet orifice is located in close proximity to a said cam which is a high pressure pump cam controlling said high pressure fuel pump tappet roller, and calibrated and oriented so as to direct lubrication to the contact area between said high pressure pump cam and said high pressure fuel pump tappet roller, and to said high pressure fuel pump tappet roller.

[0029] The invention thus makes it possible to solve the difficult problem of lubricating the high pressure fuel pump pusher roller.

[0030] The invention will be further detailed by the description of non-limiting embodiments, and on the basis of the appended figures illustrating variants of the invention, in which: - [Fig.l] schematically illustrates a motor vehicle comprising a thermal engine equipped with a camshaft; - [Fig.2] illustrates schematically and in section passing through its axis of rotation, this camshaft, one of its guide bearings, one of the cams, and an end cap distributing lubricant, according to the invention; - [Fig.3] schematically illustrates in cross-section along plane AA of [Fig.2], the same camshaft and the same cap.

[0031] [Fig.l] schematically illustrates a motor vehicle 1000 comprising at least one thermal engine 100, with at least one camshaft 200, arranged to control mechanical actuators such as valves, rocker arms, pistons, or others, equipped with an improved lubrication device for said camshaft.

[0032] The invention consists more particularly in using a plug at the end of the camshaft to bring the lubricant from the camshaft bearing to the high pressure fuel pump cam and the roller of its tappet, using a circulation of lubricant internal to the camshaft.

[0033] This camshaft plug, fitted at the end of the camshaft, comprises a lubricant chamber arranged by isolation from the rest of the interior of the camshaft with a sealing means, in particular and not limited to an O-ring, as visible in [Fig.2].

[0034] Naturally, the seal can be ensured in any case, and in particular without a seal, in particular by the plug body itself, or by a particular arrangement of the interior of the camshaft, or by another added sealing means, for example a tube or the like.

[0035] The lubricant chamber is supplied through an orifice provided in the camshaft tube from the camshaft bearing.

[0036] The lubricant chamber supplies the area of ​​the high pressure pump control cam via a peripheral flat which opens onto a hole in the camshaft tube made at the foot of the high pressure pump control cam.

[0037] The lubricant supplied to the foot of the high pressure pump control cam is projected towards the pump pusher roller by centrifugation.

[0038] More particularly, as visible in [Fig.2] and [Fig.3], the camshaft 200 is guided in rotation around an axis of rotation D by at least one support bearing 210, and carries at least one cam 220 for controlling a radial movement, in a direction perpendicular to said axis of rotation D, of at least one actuator 230.

[0039] This camshaft 200 is at least locally hollow and arranged to contain a lubricant, and comprises at least one end plug 240, which is arranged to prevent the axial exit of this lubricant from the camshaft 200.

[0040] According to the invention, this at least one end plug 240 comprises at least one lubricant circulation channel 250, which is arranged to allow the circulation of lubricant between at least one inlet orifice 260 and one radial and calibrated outlet orifice 270 in line with such an actuator 230.

[0041] More particularly, this at least one inlet orifice 260 is provided at the level of a said support bearing 210.

[0042] More particularly, this at least one lubricant circulation channel 250 comprises a first annular chamber 251, which is limited between surfaces of this at least one end plug 240 and a seal 280 interposed under pressure between a bore 209 that the camshaft 200 comprises and the at least one end cap 240. This first annular chamber 251 is arranged to distribute lubricant to a second lateral chamber 252 opening onto the outlet orifice 270.

[0043] More particularly, the second lateral chamber 252 is limited, on the one hand by the bore 209 of the camshaft 200, and on the other hand by a flat 241 formed in this at least one end plug 240 in the direction of the axis of rotation D.

[0044] More particularly, the seal 280 is housed in a groove 249 which is included in said at least one end plug 240.

[0045] More particularly, said seal 280 is located, in the direction of the axis D, at the level of a support bearing 210.

[0046] More particularly, an actuator 230 is a high pressure fuel pump tappet roller, and an outlet orifice 270 is located in close proximity to a said cam 220 which is a high pressure pump cam controlling this high pressure fuel pump tappet roller, and is calibrated and oriented so as to direct lubrication to the contact area between the high pressure pump cam and the high pressure fuel pump tappet roller, and to the high pressure fuel pump tappet roller.

[0047] If a device for distributing lubricant at the level of the camshaft through a bearing is known from the prior art, the invention makes it possible to avoid such an arrangement, which is difficult to produce and sensitive to any pollution, by proposing, through the use of such a hollow camshaft plug, to position exactly a calibrated orifice at the right angle of the high pressure pump by channeling the lubricant between channels formed in such a shaft plug and an internal wall of a hollow camshaft in the receiving zone of the plug. In the same way, the invention makes it possible to bring, without requiring complex manufacturing, lubricant to any point arranged along the camshaft.

[0048] The invention makes it possible to significantly improve the lubrication of the camshaft, at the cost of minor modifications to existing components. It avoids having to create a complex lubricant circulation in the camshaft bearing cap housing. The use of a lubricant circulation in the camshaft cap avoids the heavy investments required to create a lubricant pipe directly in the camshaft carrier or the cylinder head of the thermal engine.

[0049] The invention makes it possible to precisely regulate and control the radial flow of the lubricant, in particular the oil, directed towards the area to be lubricated, and thus to increase the service life of the device concerned.

Claims

Claims

1. Motor vehicle (1000) comprising at least one heat engine (100) itself comprising at least one camshaft (200) guided in rotation about an axis of rotation (D) by at least one support bearing (210) and carrying at least one cam (220) for controlling a radial movement, in a direction perpendicular to said axis of rotation (D), of at least one actuator (230), said at least one camshaft (200) being at least locally hollow and arranged to contain a lubricant, and comprising at least one end plug (240) arranged to control the radial output and prevent the axial output of said lubricant from said at least one camshaft (200), characterized in that said at least one end plug (240) comprises at least one lubricant circulation channel (250) arranged to allow the circulation of lubricant between at least one inlet orifice (260) and a radial and calibrated outlet orifice (270) in line with a said actuator (230).

2. Motor vehicle (1000) according to claim 1 characterized in that said at least one inlet orifice (260) is provided at the level of a said support bearing (210).

3. Motor vehicle (1000) according to claim 1 or 2 characterized in that said at least one lubricant circulation channel (250) comprises a first annular chamber (251) limited between surfaces of said at least one end plug (240) and at least one sealing surface comprised in a bore (209) comprised in said at least one camshaft (200) and / or comprised in said at least one end plug (240) and / or comprised in a sealing component carried by said bore (209) or said end plug (240), said first annular chamber (251) being arranged to distribute lubricant to a second lateral chamber (252) opening onto said outlet orifice (270).

4. Motor vehicle (1000) according to claim 3 characterized in that said bore (209) comprises a said sealing surface.

5. Motor vehicle (1000) according to claim 3 characterized in that said end cap (240) comprises a said sealing surface.

6. Motor vehicle (1000) according to claim 3 characterized in that said bore (209) or said end cap (240) carries a said sealing component which is a seal (280) interposed under pressure between said bore (209) and said at least one end plug (240).

7. Motor vehicle (1000) according to claim 6 characterized in that said second lateral chamber (252) is limited, on the one hand by said bore (209) of said at least one camshaft (200), and on the other hand by a flat (241) formed in said at least one end plug (240) in the direction of said axis of rotation (D).

8. Motor vehicle (1000) according to claim 6 or 7 characterized in that said seal (280) is housed in a groove (249) which said at least one end plug (240) comprises.

9. Motor vehicle (1000) according to one of claims 6 to 8 characterized in that said seal (280) is located at the level of a said support bearing (210).

10. A motor vehicle (1000) according to one of claims 1 to 9 characterized in that a said actuator (230) is a high pressure fuel pump tappet roller, and in that a said outlet orifice (270) is located in the immediate vicinity of a said cam (220) which is a high pressure pump cam controlling said high pressure fuel pump tappet roller, and calibrated and oriented so as to direct lubrication to the contact area between said high pressure pump cam and said high pressure fuel pump tappet roller, and to said high pressure fuel pump tappet roller.

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