ASSEMBLY IN THE FORM OF A CYLINDER BLOCK AND A WATER PUMP, EQUIPPED WITH POSITIONING AND ERROR-PROOFING MEANS, IN A VEHICLE INTERNAL COMBUSTION ENGINE

Abstract

The assembly consists of a cylinder block for an internal combustion engine and a water pump (PO) for an engine cooling system, and includes positioning and alignment means (DI1, DI2) arranged in a mechanical interface of the cylinder block and a complementary mechanical interface (IMP) of the water pump. According to the invention, the positioning and alignment means comprise at least one pair of permanent magnets (PM), the first and second permanent magnets of the pair being arranged respectively in the mechanical interface of the cylinder block and the complementary mechanical interface of the water pump so as to produce a magnetic attraction force facilitating assembly when the water pump is compatible with the cylinder block and a magnetic repulsion force preventing assembly otherwise. Figure 3

Description

Title of the invention: ASSEMBLY FORMED BY A CYLINDER BLOCK AND A WATER PUMP, EQUIPPED WITH POSITIONING AND FOOLPROOFING MEANS, IN A VEHICLE HEAT ENGINE

[0001] The present invention relates generally to the assembly, with positioning and keying means, of a water pump on a cylinder block of a vehicle heat engine. More particularly, the invention relates to an assembly formed of a cylinder block and a water pump, provided with positioning and keying means, the water pump forming part of the cooling system of the heat engine.

[0002] Known to the inventive entity is an assembly of a water pump on a cylinder block of a motor vehicle heat engine in which two pins associated with corresponding housings are used for positioning the water pump on the cylinder block. The positioning pins are mounted projecting in housings of a mechanical interface of the water pump. Corresponding positioning housings are arranged in a complementary mechanical interface of the cylinder block. The positioning of the water pump on the cylinder block is obtained by the engagement of the pins in the positioning housings of the cylinder block.

[0003] In this same assembly of the prior art, the aforementioned positioning pins and housings also fulfill a keying function. This keying function makes it possible to ensure that the water pump mounted on the cylinder block is indeed the correct reference. Given the extensive standardization in automobile construction, water pumps for thermal engines of different types, such as a naturally aspirated gasoline engine and a turbocharged gasoline engine, can have similar external appearances and mechanical interfaces based on the same standard model. The differentiation of the mechanical interfaces by a different location of the housings and positioning pins makes it possible here to obtain the desired keying.

[0004] The solution described above of the prior art has disadvantages. The diversity of the location of the pin housings to differentiate the water pumps results in manufacturing costs relating in particular to tools, machine cycle time and others. In addition, the ergonomics of the mounting of the water pump on the cylinder block is not satisfactory, because it requires effort from the operator to position the pump on the cylinder block.

[0005] Document FR2859424A1 discloses a device for attaching portable equipment in a vehicle. This device comprises a mounting bracket on the vehicle and a holding portion for receiving the portable equipment. The mounting bracket and the holding portion comprise magnetic pads which form keying means for their assembly. The magnetic pads are arranged in identical patterns so that they face each other when the holding portion is assembled on the mounting bracket. The polarities of the magnetic pads are arranged such that the pads of the mounting bracket repel those of the holding portion when the latter is presented with an incorrect orientation, and attract the pads of the holding portion when the latter is presented with the correct orientation.

[0006] The present invention aims to provide an assembly formed of a cylinder block and a water pump, the assembly being provided with positioning and keying means which do not have the aforementioned drawbacks of the prior art.

[0007] According to a first aspect, the invention relates to an assembly formed by a heat engine cylinder block and a water pump of a heat engine cooling system, the assembly comprising positioning and keying means arranged in a mechanical interface of the cylinder block and a complementary mechanical interface of the water pump. According to the invention, the positioning and keying means comprise at least one pair of permanent magnets, first and second permanent magnets of the pair being arranged respectively in the mechanical interface of the cylinder block and the complementary mechanical interface of the water pump so as to produce a magnetic attraction force facilitating assembly when the water pump is compatible with the cylinder block and a magnetic repulsion force preventing assembly otherwise.

[0008] According to a particular characteristic, the first and second permanent magnets are inserted into respective housings of the mechanical interface of the cylinder block and the complementary mechanical interface of the water pump, so as to form in cooperation with the housings a fitted assembly of cup and tenon ensuring positioning and keying functions.

[0009] According to another particular characteristic, the permanent magnets and the respective housings have circular and / or oblong cylindrical shapes.

[0010] According to yet another particular characteristic, at least one of the permanent magnets is a rare earth permanent magnet.

[0011] According to yet another particular characteristic, at least one of the permanent magnets is a permanent magnet without rare earths.

[0012] According to yet another particular characteristic, the positioning means and The keying devices comprise two pairs of permanent magnets, first permanent magnets of the two pairs being arranged in the mechanical interface of the cylinder block and second permanent magnets of the two pairs being arranged in the complementary mechanical interface of the water pump.

[0013] The invention also relates to a heat engine, such as a naturally aspirated gasoline engine or a turbocharged gasoline engine, comprising an assembly as briefly described above.

[0014] The invention also relates to a motor vehicle comprising a heat engine as indicated above.

[0015] Other advantages and characteristics of the present invention will appear more clearly on reading the detailed description below of several particular embodiments of the invention, with reference to the appended drawings, in which:

[0016] [Fig-1] is a partial perspective view of a heat engine cylinder block intended to receive a water pump from the thermal engine cooling system.

[0017] [Fig.2] is a perspective view of a pellet-shaped permanent magnet used for positioning and keying in an assembly according to the invention formed of a cylinder block and a water pump.

[0018] [Fig.3] a perspective view of a water pump intended to be mounted on the block- thermal engine cylinders of [Fig.l].

[0019] With reference to [Fig.l] and [Fig.2] and to [Fig.3], a particular embodiment of an assembly according to the invention formed of a cylinder block BC and a water pump PO is now described by way of example. The cylinder block BC and the water pump PO are here, for example, components of a naturally aspirated gasoline engine or a turbocharged gasoline engine. The bodies of the cylinder blocks BC and the water pump PO are parts made of aluminum, which is a paramagnetic material with a low magnetic permeability, close to 1.

[0020] As visible in [Fig.l], the cylinder block BC includes a mechanical interface IMB provided for the mounting of the water pump PO.

[0021] The mechanical interface IMB comprises several tapped holes OT for fixing the water pump PO by screwing, as well as positioning and keying means ID1 and ID2.

[0022] The positioning and keying means ID1, ID2, shown in section in an enlargement AG of [Fig.l], each comprise a housing TL in the form of a circular, or oblong, cylindrical hole, and a permanent magnet PM in the form of a circular, or oblong, cylindrical pellet.

[0023] The permanent magnet PM, better visible in [Fig.2], comprises a north pole N and a south pole S corresponding to opposite end faces thereof. The magnet permanent magnet PM is inserted into its housing TL, until it comes to a stop, and is held in place in the housing by gluing or other means. The permanent magnet PM is oriented here in the housing TL with its south pole S facing the bottom of the housing and its north pole N facing the opening of the housing. The depth PR of the housing TL is greater than the height HA of the permanent magnet PM, so that a positioning and keying cup CU is created once the permanent magnet PM is placed in its housing TL. The bottom of the cup CU is formed here by the north pole face N of the permanent magnet PM.

[0024] As seen in [Fig.3], the water pump PO comprises a mechanical interface IMP provided for mounting the water pump PO on the cylinder block BC.

[0025] The mechanical interface IMP comprises several screw passage holes TO for fixing the water pump PO to the corresponding mechanical interface IMB of the cylinder block BC, as well as positioning and keying means DU and DI2.

[0026] The positioning and keying means DU, DI2, shown in section in an enlargement GA of [Fig. 3], each comprise a housing LT in the form of a circular or oblong cylindrical hole, and a permanent magnet PM like that integrated in the mechanical interface IMB of the cylinder block BC. The positioning and keying means DU, DI2, of the mechanical interface IMP and those ID1, ID2, of the mechanical interface IMB are installed according to the same pattern so as to come into contact, respectively, during the assembly of the water pump PO on the cylinder block BC.

[0027] The permanent magnet PM is inserted into its housing LT, until it comes to a stop, and is held in place in the housing by gluing or other means. The permanent magnet PM is oriented here in the housing LT with its north pole N facing the bottom of the housing and its south pole S outside the housing. The depth RP of the housing LT is less than the height HA of the permanent magnet PM, so that once the magnet PM is placed in its housing LT, a portion of the magnet PM projects outside the housing LT and forms a positioning and keying pin TP with a magnetic polarization S.

[0028] The projection of the permanent magnet PM outside the housing LT is determined so that the positioning and keying tenon TP thus formed can be housed entirely, in an adjusted manner, in the corresponding positioning and keying cup CU.

[0029] When assembling the water pump PO on the cylinder block BC, the operator places the mechanical interface IMP of the pump opposite that IMB of the cylinder block. Given that the positioning and keying cups CU and the positioning and keying pins TP have opposite magnetic polarities, respectively N and S in the example described, the attractive force exerted between them allows easy installation of the water pump PO on the cylinder block BC, without that the operator needs to force.

[0030] In the invention, the keying function is obtained thanks to the direction of placement of the permanent magnets. To achieve keying between two different thermal engines, for example between a naturally aspirated gasoline engine and a turbocharged gasoline engine, the CU cups of the mechanical interface IMB of the cylinder block BC and the TP pins of the mechanical interface IMP of the water pump PO will have the magnetic polarities north N and south S, respectively, for one type of engine, and the magnetic polarities south S and north N, respectively, for the other type of engine. Thus, when the water pump PO which is presented for assembly on a cylinder block BC is not the correct reference, the CU cups and TP pins have identical magnetic polarities and assembly is prevented by the repulsion force.

[0031] Different types of permanent magnets, with rare earths and without rare earths, may be used depending on the application. It should be noted that the number of “cup-magnetized stud” pairs is not limited to two as in the embodiment described above. Depending on the power of the type of magnet chosen, the number of “cup-magnetized stud” pairs will be adjusted so as to obtain the desired magnetic attraction / repulsion force. An embodiment with a single “cup-magnetized stud” pair is also included in the invention, with possibly another positioning means, knowing that the keying function may be fully ensured by the single “cup-magnetized stud” pair. Furthermore, it should be noted that the shapes of the permanent magnets and their housings are not limited to circular or oblong cylindrical shapes.

[0032] The invention is not limited to the particular embodiments which have been described here by way of example. Those skilled in the art, depending on the applications of the invention, will be able to make various modifications and variants falling within the scope of protection of the invention.

Claims

Claims

1. Assembly formed of a cylinder block (BC) of a heat engine and a water pump (PO) of a cooling system of said heat engine, said assembly comprising positioning and keying means (ID1, DU, ID2, DI2) arranged in a mechanical interface (IMB) of said cylinder block (BC) and a complementary mechanical interface (IMP) of said water pump (PO), characterized in that said positioning and keying means (ID1, DU, ID2, DI2) comprise at least one pair of permanent magnets (PM, ID1, DU;PM, ID2, DI2), first (PM, ID1, ID2) and second (PM, DU, DI2) permanent magnets of said pair being arranged respectively in said mechanical interface (IMB) of said cylinder block (BC) and said complementary mechanical interface (IMP) of said water pump (PO) so as to produce a magnetic attraction force facilitating assembly when said water pump (PO) is compatible with said cylinder block (BO) and a magnetic repulsion force preventing said assembly otherwise.;

2. Assembly according to claim 1, characterized in that said first (PM, ID1, ID2) and second (PM, DU, DI2) permanent magnets are inserted into respective housings (TL, LT) of said mechanical interface (IMB) of said cylinder block (BC) and said complementary mechanical interface (IMP) of said water pump (PO), so as to form in cooperation with said housings (TL, LT) a fitted assembly of cup (CU) and tenon (TP) ensuring positioning and keying functions.

3. Assembly according to claim 2, characterized in that said permanent magnets (PM) and housings (TL, LT) have circular and / or oblong cylindrical shapes.

4. Assembly according to any one of claims 1 to 3, characterized in that at least one of said permanent magnets (PM) is a rare earth permanent magnet.

5. Assembly according to any one of claims 1 to 3, characterized in that at least one of said permanent magnets (PM) is a permanent magnet without rare earths.

6. Assembly according to any one of claims 1 to 5, characterized in that said positioning and keying means comprise two pairs of permanent magnets (PM, ID1, DU; PM, ID2,

7.

8.

9.

10. DI2), first permanent magnets (PM, ID1, ID2) of said two pairs being arranged in said mechanical interface (IMB) of said cylinder block (BC) and second permanent magnets (PM, DU, DI2) of said two pairs being arranged in said complementary mechanical interface (IMP) of said water pump (PO). Heat engine characterized in that it comprises an assembly (BC, PO) according to any one of claims 1 to 6. Thermal engine according to claim 7, characterized in that it is of the atmospheric gasoline type. Thermal engine according to claim 7, characterized in that it is of the turbocharged gasoline type. Motor vehicle characterized in that it comprises a heat engine according to any one of claims 7 to 9.

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