EP1874596A1

EP1874596A1 - Toothed wheel

Info

Publication number: EP1874596A1
Application number: EP06742623A
Authority: EP
Inventors: Christophe Lassalle
Original assignee: Valeo Systemes dEssuyage SAS
Current assignee: Valeo Systemes dEssuyage SAS
Priority date: 2005-04-29
Filing date: 2006-04-20
Publication date: 2008-01-09
Also published as: WO2006117084A1; RU2007144183A; MX2007013562A; FR2885198A1; CN101203409A; JP2008539372A; FR2885198B1; BRPI0610393A2; US20100011892A1; KR20080013917A

Abstract

The invention relates to a toothed wheel (1) comprising a central bore (12) which defines a central rotation axle (3) and a secondary bore (13) in which a crank pin (4) is fixed. The invention is characterised in that one of the faces thereof (1a) is equipped with means (10) for determining the distance between the central axle (3) of the central bore (12) and the axle of the crank pin (4) in the secondary bore (13), said means (10) taking the form of coding means (10).

Description

WHEEL

The present invention relates to a toothed wheel, and more specifically to the production of means for differentiating the toothed wheels.

More specifically, in motors, for example of the wiper motors motor vehicle type, it is commonly used gear wheels for the transmission of the movement, this transmission is done with a crankpin connected to the connecting rod and guided by a stud located on one of the faces of the toothed wheel.

These gears are usually made from a molded wheel traversed by a wheel shaft, having a serration on their rim and having on one of their face a recess into which a cam is inserted.

These wheels are typically connected by a set of moving parts to an output drive shaft, for example a drive shaft of a wiper arm in the case of wiper motors.

Currently, the distance between the axis of the rotation of the toothed wheel and the axis of the crankpin, fixed on one of the faces of the gear wheel, commonly called "spacing", makes it possible to determine the output rotation angle of the drive shaft connected for example to a wiper arm.

Therefore, it is important to know this distance to determine the angle of rotation output of the drive shaft and consequently the sweep angle of the wiper arm in the case of a wiper motor.

However, because of the relatively small size of the engine parts, it is often difficult to quantify precisely the naked eye, this distance being generally of the order of a centimeter and varying only a few millimeters to cause problems. different angles of rotation.

A first method of quantification is to measure manually the center distance using a ruler or a measuring device, which however does not allow to have a sufficiently precise and reliable measurement, because of the margin of measurement. error inherent in manual measurement. An alternative solution consists in producing, for example, electronic measuring devices by optical reading of this center distance.

However, these devices are relatively heavy to set up, expensive and are likely to malfunction.

In order to remedy these problems, it is known in the prior art to incorporate coloring pigments in the basic material constituting the wheel, each color corresponding to a given spacing.

However, besides the fact that the number of colors recognizable by a human being is limited and subject to error for colors of similar hues, it should be noted that the addition of pigments in the base material of the wheels also modifies the intrinsic characteristics. of the material.

It would therefore be particularly advantageous to make differentiating means of a gear wheel easily understandable by a human being, requiring only one mold for the formation of the wheel and not causing a change in the intrinsic characteristics of the base material. of the wheel.

Moreover, in wiper motors, the wheels and their cam used are different according to the direction of sweeping and the configuration of the motor.

Indeed, depending on the available location for fixing an engine, for example the type of windshield wiper, it is of the "right" or "left" type.

Likewise, depending on the direction of sweeping of the wiper arm, the motor is said to have a fixed stop type on the right or a fixed stop on the left.

The difference between these types of motors affects the cam associated with the surface of the gear wheel.

It is currently impossible for those skilled in the art, by directly visualizing the wheel and in particular the face of the wheel where the cam is inserted, to determine whether the wheel is intended for a right or left engine or an engine. with fixed stop right or left. It would therefore be particularly advantageous to also make differentiation means of a toothed wheel allowing, in addition to the simple determination of the center distance of the wheel, but also the determination of the type of engine in which the wheel fits.

The present invention proposes to solve the problems related to the prior art using a toothed wheel with easily understandable differentiation means, not requiring a complex molding and inexpensive.

The present invention relates to a toothed wheel having a central bore defining a central axis of rotation and a secondary bore for fixing a crank pinion, characterized in that it has, on one of its faces, means for determining the the distance between the central axis of the central bore and the pin axis of the secondary bore, the determination means being in the form of coding means made from a plurality of projecting elements provided on the face of the wheel on which is fixed the crankpin.

Advantageously, the projecting elements are substantially cylindrical and at least one of the projecting elements has a transverse wall forming a diameter of this projecting element.

In order to further differentiate certain characteristics of the gears, a bore is provided in the bottom of at least one of the projecting elements.

In order to allow a homogeneous molding of the wheel, the projecting elements are located on the same circle centered on the central bore.

The present invention also relates to a method of differentiating a gear wheel according to the preceding characteristics, characterized in that it comprises the step of reading a binary code according to the presence or absence of a wall in the projecting elements as well as the step of determining a characteristic of the gear as a function of the presence or absence of a bore in the bottom of the projecting elements.

The present invention is now described by way of purely illustrative and non-limiting examples of the scope of the present invention and from the following illustrations, in which: FIG. 1 represents a perspective view of a toothed wheel linked by a crank pin to a connecting rod and having the coding means according to the invention;

Figure 2 shows a lower perspective view of a toothed wheel coupled to a cam;

Figure 3 is a perspective view of a toothed wheel with the encoding means according to the invention;

FIG. 4 represents an upper view of a toothed wheel with the coding means according to the invention; and FIGS. 5 and 6 are more detailed top views of the coding means of a wheel according to the invention.

FIG. 1 is a perspective view of a wheel 1 having on its peripheral rim a toothing 2 and in its center an axis of rotation 3.

It is provided on one face of the wheel 1, said fixing face of the crank pin la, a bore (not visible in Figure 1) in which is inserted a crankpin 4, of a type known per se.

The crankpin 4 is itself inserted into the end of a connecting rod 5 whose other end is connected by a second crankpin 6 with two rockers 7, of a type known per se.

An output shaft 8 guides the rockers 7, the angle of rotation of which is determined in particular by means of the angle of rotation of the wheel 1 and the movement thus transmitted, the toothed end 5a of the connecting rod 5 being suitable for meshing in a toothed end sector 9 of the output shaft 8.

The attachment face 1c of the crankpin 4 has the coding means 10 according to the invention, the embodiment of which will be explained later.

2 shows a perspective view of the face Ib of the wheel 1 in which a cam 11, of known type, is inserted.

It is determined by the conformation of the cam 11 that it is determined whether the wheel 1 is intended for a wiper motor of the left or right type or with a fixed stop on the right or on the left.

FIG. 3 represents a perspective view of the wheel 1 with the coding means 10 according to the invention. The wheel 1 has a central bore 12 in the form of a sleeve or boss for the central rotation shaft 3 and a secondary bore 13, also in the form of a sleeve or boss, intended for the fixing the crankpin 4 on the wheel 1 and defining the axis of the crankpin 4.

The distance between the central axis of rotation 3 and the axis of the crankpin 4 is commonly called the "center distance" and makes it possible to determine the angle of rotation of the output shaft 8, for example the scanning angle of the windshield wiper arm in the case of the incorporation of the toothed wheel 1 into a wiper motor.

The coding means 10 on the so-called fixing face of the crank pin 1a of the wheel 1 are in the form of a plurality of projecting elements (14, 15, 16, 17), advantageously in the form of four elements protrusion (14, 15, 16, 17) substantially cylindrical.

Advantageously, the projecting elements (14, 15, 16, 17) are located on a same circle of center the central bore 12 of the axis of rotation 3 of the wheel 1 and are interconnected by curved walls 18.

In addition, the secondary bore 13 is also located on the same circle.

More precisely, the fixing face 1a of the wheel 1 has a circular inner depression 19 on which the protruding elements (14, 15, 16, 17) and the curved walls 18 abut.

Walls in the form of parallelepipedal elements 20 are also formed between the periphery of the internal circular digging 19 and the projecting elements (14, 15, 16, 17) circular.

These parallelepipedal elements 20 are said to be "external" because they lie outside the circle defined by the cylindrical projecting elements (14, 15, 16, 17) and are substantially radial with respect to the central axis of rotation 3 of the wheel. 1, that is to say located on a radius of the wheel 1.

Walls in the form of projecting parallelepipedal elements 21 are also provided between the central bore 12 and each of the cylindrical projecting elements (14, 15, 16, 17) and between the secondary bore 13 and the intermediate bore 13. central bore 12. These parallelepipedal elements 21 are called "internal" because they are located inside the circle defined by the circular projecting elements (14, 15, 16, 17) and are substantially radial with respect to the central axis of rotation 3 of the wheel. 1, that is to say located on a radius of the wheel 1.

Similarly, there is provided a pair of parallel walls (22, 23) connecting the secondary bore 13 to the main bore 12 and a plurality of walls (24, 25, 26) between the inner periphery of the inner bore 19 of the fastening face 1a and the sleeve of the secondary bore 13.

It is understood in the following description by elements "projecting" lower projecting elements (14, 17) directly connected by a curved wall 18 to the boss of the secondary bore 13 and by projecting elements "upper" the elements projecting (15, 16) directly connected only by curved walls 18 to another projecting element (14, 15, 16, 17) and not to the sleeve of the secondary bore 13.

It is thus represented in the figures two upper projecting elements (15, 16) and two lower projecting elements (14, 17).

It is, however, within the skill of those skilled in the art to modify the number of protruding elements (14, 15, 16, 17) present on the attachment face 1a of the wheel 1.

Thus, it is possible to make wheels 1 with only one projecting element or with more than four projecting elements.

In each projecting element (14, 15, 16, 17) there is optionally provided a transverse wall 27 and advantageously forming a substantially radial diameter of the projecting element (14, 15, 16, 17). that is located on a radius of the wheel 1, and connecting the so-called "internal" projecting wall 21 to the so-called "outer" projecting wall 20.

Similarly, it is also possible to provide bores 28 passing through the toothed wheel 1, advantageously associated with each projecting element (14, 15, 16, 17), and more advantageously provided in the bottom of each projecting element ( 14, 15, 16, 17).

The cylindrical protruding elements (14, 15, 16, 17) are coding means 10 making it possible to determine in a simple manner the wheel / crankset spacing. Indeed, each projection element (14, 15, 16, 17) is affiliated with a binary code, ie 0 or 1, depending on the absence or the presence of the transverse wall 27 in the protruding element (14). , 15, 16, 17).

Thus, by convention, the number 0 is assigned to a protruding element (14,

15, 16, 17) having no transverse wall 27 and the code 1 is assigned to a projecting element (14, 15, 16, 17) having a transverse wall 27.

It is understood that the opposite is also conceivable, that is to say the assignment of a code 0 for the presence of a transverse wall 27 and a code 1 for the absence of transverse wall 27 .

Still conventionally, the reading direction of the binary codes of the projecting elements (14, 15, 16, 17) is clockwise from: - the lower projecting element 14 connected by a curved wall 18 to the boss of the secondary bore 13 and located to the left of this boss 13 when the user looks at the attachment face of the wheel 1 with the boss of the secondary bore 13 directed towards the user, then the upper projecting element 15 located to the left of the user always with the boss of the secondary bore 13 directed towards the user, then the upper projecting element 16 located to the right of the user with the boss of the secondary bore 13 directed towards the user, and finally the lower projecting element 17 located to the right of the user with the boss of the secondary bore 13 directed towards the user.

Alternatively, it is understood that the reading direction of the binary codes of the projecting elements (14, 15, 16, 17) can also be done in a counter-clockwise direction starting from the element in question. lower right projection 17.

Thus, in FIGS. 3 and 4, by assigning 0 to a projecting element (14, 15,

16, 17) having no transverse wall 27, there is shown a wheel

I with the binary coded number 1101, this code can correspond to a determined distance between centers and a determined exit angle.

It is understood that it is within the skill of one skilled in the art to change the four-digit binary code for a given distance and a given exit angle. Indeed, starting from a wheel with four projecting elements, it is possible to obtain 2 ⁴ = 16 different binary codes and thus to differentiate between sixteen different distances and angles of exit.

It will of course be understood by those skilled in the art that it is possible to produce more or less cylindrical protruding elements (14, 15, 16, 17) depending on the number of digits in binary codes that it wishes to obtain for to differentiate a more or less important number of distances.

In addition, in order to differentiate the types of motors in which the toothed wheel 1 must be integrated, it is possible to make the bore 28 in the bottom of the projecting elements (14, 15, 16, 17), that is to say in the interior space of the fixing face 1a of the wheel 1 defined by each projecting element (14, 15, 16, 17).

By convention, it is decided that a bore 28 made in the upper projecting elements (15, 16) corresponds to the determination of the right or left type motor, the bore 28 being drilled in the bottom of the element. in the upper left projection 15 when the wheel 1 is intended to be integrated in a motor is of the left type and the bore 28 is drilled in the bottom of the upper right protruding element 16 when the wheel 1 is intended to be integrated in a right type motor.

Similarly, still conventionally, it is decided that a bore 28 made in the lower projecting elements (14, 17) corresponds to the determination of the fixed stop motor to the right or to the left, the bore 28 being pierced in the bottom of the left lower protruding element 14 when the wheel

I is intended to be integrated in a motor is of the fixed stop type on the left and the bore 28 is drilled in the bottom of the right lower projection element 17 when the wheel 1 is intended to be integrated in a motor type at a fixed stop on the right.

Thus, the wheel 1 as illustrated in Figure 4 is intended to be integrated in a left type motor and fixed stop right.

It is understood that it is within the skill of those skilled in the art to give any meaning to the characteristics of the toothed wheel 1, or any other element related to the toothed wheel 1, as a function of the absence or the presence of a bore 28 in the bottom of the projecting elements (14, 15, 16, 17), and more precisely in the interior space of the attachment face of the wheel 1 defined by each element protruding (14, 15, 16, 17). It is thus clearly easier to differentiate the gears 1 and quickly determine in what type of engine it is intended to be integrated.

It is the same for the determination of the center distance from a table of concordance between the binary code, the center distance and the exit angle that the user is learned by heart, or consults to determine the distance between .

Errors in the measurement and reading of the center distance and therefore the angle of rotation of the output shaft are thus avoided.

In addition, in order to facilitate the reading direction of the coding means (10), a logo or inscription is added between the two upper projecting elements (15, 16), this logo or inscription to be located horizontally. and at the point when the user reads the coding means (10) clockwise from the lower left protruding element 14 to finish at the lower right protruding element 17.

Furthermore, it is thus advantageously made gear wheels with coding means that can be machined from the same tool and can be crushed.

Indeed, it is possible to easily modify the forming mold of the toothed wheel 1 to integrate the presence or absence of through walls 27 inside the elements (14, 15, 16, 17).

In addition, the ground powder obtained after grinding the wheels 1 can be used again, which was not the case according to the prior art during the incorporation of coloring pigments.

Claims

A toothed wheel (1) having a central bore (12) defining a central axis of rotation (3) and a secondary bore (13) for fixing a crankpin (4), characterized in that it has on one of its faces (la), means (10) for determining the distance between the central axis (3) of the central bore (12) and the axis of the crankpin (4) of the secondary bore ( 13).

2. gear wheel according to claim 1, characterized in that said determining means (10) are in the form of coding means (10).

Gear wheel according to claim 1 or 2, characterized in that said determining means (10) are in the form of a plurality of projecting elements (14, 15, 16, 17) provided on the face ( la) of the wheel (1) on which is fixed said crankpin (4).

4. Gear wheel according to claim 3, characterized in that said projecting elements (14, 15, 16, 17) are substantially cylindrical.

5. gear wheel according to claim 3 or 4, characterized in that at least one of said projecting elements (14, 15, 16, 17) has a transverse wall (27).

6. gear wheel according to the preceding claim, characterized in that said transverse wall (27) forms a diameter of said at least one of said substantially cylindrical projecting elements (14, 15, 16, 17).

Gear wheel according to one of Claims 3 to 6, characterized in that a bore (28) is provided in the bottom of at least one of said projecting elements (14, 15, 16, 17).

8. gear wheel according to one of claims 3 to 7, characterized in that said projecting elements (14, 15, 16, 17) are located on the same circle centered on the central bore (12).

9. Differentiation method of a toothed wheel (1) according to one of claims 3 to 8, characterized in that it comprises the step of reading a binary code according to the presence or absence of a wall (27) in said projecting elements (14, 15, 16, 17).

10. Differentiation method of a gear according to the preceding claim, characterized in that it comprises the step of determining a characteristic of the toothed wheel according to the presence or absence of a bore (28). ) in the bottom of said projecting elements (14, 15, 16, 17).