阅读说明：本技术 具有紧配合在平衡部件上的偏心轴的机械装置 (Mechanical device with eccentric shaft tightly fitted on balance member ) 是由 泽维尔·勒拉塞克斯 伽兹高兹·米图凯威斯 于 2018-05-17 设计创作，主要内容包括：本发明涉及一种机械装置(DM),其包括：轴(AP),该轴具有相对的两个端部(PT1-PT2),该两个端部具有第一转动轴线(AR1)并由中间部分(PI)隔开,该中间部分具有相对于第一转动轴线(AR1)偏心的第二转动轴线(AR2)；以及部件(PM),该部件包括第一部分(P1)以及第二部分(P2),该第一部分限定第一平衡块并包括第一内孔(AI1),该第一内孔以第一转动轴线(AR1)为中心并通过第一联接部分地容纳端部中的一个(PT2),该第二部分限定第二平衡块并包括第二内孔(AI2),该第二内孔以第二转动轴线(AR2)为中心并通过第二联接部分地容纳中间部分(PI)。(The invention relates to a mechanical Device (DM) comprising: a shaft (AP) having opposite ends (PT1-PT2) having a first axis of rotation (AR1) and separated by an intermediate Portion (PI) having a second axis of rotation (AR2) eccentric to the first axis of rotation (AR 1); and a component (PM) comprising a first portion (P1) defining the first weight and comprising a first internal hole (AI1) centred on the first axis of rotation (AR1) and receiving in part one of the ends (PT2) by means of a first coupling, and a second portion (P2) defining the second weight and comprising a second internal hole (AI2) centred on the second axis of rotation (AR2) and receiving in part the intermediate Portion (PI) by means of a second coupling.)

1. A machine (DM) comprising a shaft (AP) having two opposite ends (PTj) having a first axis of rotation (AR1) and separated by a middle Portion (PI) of said shaft (AP) having a second axis of rotation (AR2) offset with respect to said first axis of rotation (AR1), said machine (DM) further comprising a member (PM) comprising a first portion (P1) defining a first counterweight and comprising a first inner bore (AI1) centred on said first axis of rotation (AR1) and receiving partly one of said ends (PTj) by means of a first coupling, and a second portion (P2) defining a second counterweight and comprising a second inner bore (AI2) centred on said second axis of rotation (AR2) and receiving partly said middle Portion (PI) by means of a second coupling, -said second portion (P2) of said component (PM) has a centre of gravity positioned along a third axis, opposite said second axis of rotation (AR2) with respect to said first axis of rotation (AR1), so as to promote eccentric mass balancing, characterized in that at least one of said first and second couplings is tight.

2. Device according to claim 1, characterized in that said second portion (P2) of said component (PM) has an elliptical cross section.

3. The device according to any one of claims 1 to 2, characterized in that said first coupling is achieved by a first step defined at a first interface (IC11, IC12) between said first portion (P1) of said component (PM) and said end portion (PT2) of said shaft (AP) housed in said first internal bore (AI1), and in that said second coupling is achieved by a second step defined at a second interface (IC21, IC22) between said second portion (P2) of said component (PM) and said intermediate Portion (PI) of said shaft (AP).

4. The device according to claim 3, characterized in that said first step is defined on said end (PT2) of said shaft (AP) housed in said first internal bore (AI 1).

5. Device according to claim 3 or 4, characterized in that said second step is defined on said intermediate Portion (PI) of said shaft (AP).

6. Coupling device, characterized in that it comprises at least one mechanical Device (DM) according to any of the previous claims.

7. The apparatus of claim 8, wherein the apparatus is a gearbox.

8. Vehicle comprising a drive chain, characterized in that it comprises at least one mechanical Device (DM) according to any one of claims 1 to 5, and/or at least one coupling device according to claim 6 or 7.

Technical Field

The invention relates to a machine comprising a so-called main shaft with an eccentric portion, which should have a balancing mass for centering the inertial mass.

Background

Some devices, such as reducers, include a shaft (called a main shaft) having two opposite end portions having a first axis of rotation and separated by an intermediate portion having a second axis of rotation that is eccentric with respect to the first axis of rotation. This is particularly the case with certain retarders, which are coupled to an electric machine (or motor) or are part of a coupling device equipped to a vehicle, which may be a motor vehicle, for example.

The (fast-rotating and eccentric) primary shaft is coupled to the (slow-rotating) secondary shaft, for example, by means of a first and a second planetary gear mechanism, for example of the hypocycloidal type, defining respectively a first and a second axially offset reduction stage.

Since the eccentricity of the main shaft produces an imbalance (and more specifically an eccentric mass (planetary gear and eccentric portion)), it has been proposed, in particular in patent documents FR 2657131 and US 4,604,916, to add such balance masses (e.g., two) for moving the overall center of gravity to the main shaft. Currently, the addition of each weight is achieved by welding, or by a splined connection, pin or key. However, this addition is expensive and complicates processing. Furthermore, due to the difficulty or impossibility of positioning (index), such additions may be made at positions that are not exactly the same as the positions that have been predefined, and in this case, are not perfectly balanced and therefore cause vibrations that generate noise and accelerate wear.

Disclosure of Invention

The invention therefore aims in particular to improve this situation.

To this end, the invention proposes a mechanical device, optionally for reducing the rotation speed, comprising a (main) shaft having two opposite end portions, which have a first axis of rotation and are separated by an intermediate portion of the shaft, which intermediate portion has a second axis of rotation offset with respect to the first axis of rotation. The mechanical device also includes a component comprising:

-a first portion defining a first counterweight and comprising a first bore centred on the first axis of rotation and partially housing one of the ends of the shaft by means of a first coupling portion, and

a second part defining a second counterweight and comprising a second internal bore centred on the second axis of rotation and partially housing, through a second coupling, the intermediate part of the shaft, the second part of the member having a centre of gravity positioned along a third axis located opposite the second axis of rotation with respect to the first axis of rotation to promote the balancing of the eccentric mass.

The mechanical arrangement is characterized in that at least one of the first and second couplings may be tight.

Thus, the counterweight defined by this component can advantageously be added to the main shaft by a tight fit, and therefore it is not necessary to carry out a welding operation, nor to use a splined connection, pin or key.

The mechanical device according to the invention may comprise other features that may be adopted individually or in combination, in particular:

the second portion of the member may have an elliptical cross-section;

the first coupling may be achieved by a first step defined at a first interface between a first portion of the component and an end of the shaft received in the first bore, and the second coupling may be achieved by a second step defined at a second interface between a second portion of the component and an intermediate portion of the shaft;

the first step may be defined on the end of the shaft housed in the first bore;

the second stage may be defined on an intermediate portion of the shaft.

The invention also proposes a coupling device comprising at least one mechanical device of the above-mentioned type.

Such a device may be, for example, a gearbox.

The invention also relates to a vehicle, possibly of the motor vehicle type, comprising a drive chain comprising at least one mechanical device of the above-mentioned type and/or at least one coupling device of the above-mentioned type.

Drawings

Other features and advantages of the present invention will become apparent upon review of the following detailed description and the accompanying drawings in which:

figure 1 schematically shows an embodiment of a part of a mechanical device according to the invention in a longitudinal plan sectional view, and

fig. 2 schematically shows a part of the mechanical arrangement of fig. 1 in a front view.

Detailed Description

The invention is particularly intended to propose a mechanical device DM with an eccentric spindle AP which is a close fit on the balancing member PM.

In the following, as a non-limiting example, the mechanical device DM is considered to be a retarder for a motor vehicle fitted to, for example, a car. However, the invention is not limited to this application. In fact, the mechanical device according to the invention may be coupled to any electric machine (or motor) or may be part of a coupling device (e.g. a gearbox). Thus, the mechanical device according to the invention can be equipped, for example, to a (land, sea (or river) or air) vehicle, optionally an industrial type of installation, or a building.

Furthermore, as a non-limiting example, the mechanical device DM is considered hereinafter for coupling to an electric prime mover that is part of the drive train of a hybrid or purely electric type vehicle. The term "electric prime mover" refers herein to an electric machine (or motor) configured to provide or recover torque for moving a vehicle, either alone or in combination with at least one optional other electric or thermal prime mover (e.g., a heat engine).

Fig. 1 and 2 schematically show an embodiment of a part of a mechanical device DM, here a retarder, according to the invention. The portion shown only includes the eccentric spindle AP and the balance member PM.

The main shaft AP includes two end portions PTj (j ═ 1 or 2) opposite each other and separated by the intermediate portion PI.

The two end portions PTj have a first axis of rotation AR 1. It should be noted that in the example shown in fig. 1 without limitation, both ends PTj have the same first diameter, but this is not required.

For example, the first end PT1(j ═ 1) on the front face may be used to connect to an output shaft of an electric motor having a first rotational speed (or first rotational speed) that is optionally variable over time.

The second end PT2(j 2) on the back is rotatably mounted on a bearing.

The intermediate portion PI of the main shaft AP has a second axis of rotation AR2, the second axis of rotation AR2 being offset from the first axis of rotation AR1 by a distance e. The intermediate portion PI may not be limited to receiving first and second planetary gear mechanisms, such as of the hypocycloidal or epicycloidal type, defining first and second reduction stages, respectively, axially offset, and ensuring the coupling of the primary shaft AP, on which the intermediate portion PI is located, to the secondary shaft. It will be understood that the first and second planetary gears are responsible for converting the first rotational speed of the primary shaft AP into a second rotational speed of the secondary shaft, which is strictly less than the first rotational speed.

The present invention does not relate to the first and second planetary gear mechanisms, which will not be described hereinafter.

The (balancing) member PM comprises a first portion P1 and a second portion P2 mutually elongated by being fastened to each other in one piece. It should be noted that the (balancing) member PM is preferably integral. This is not necessary, however. In practice, the component PM may be constituted by a first portion P1 thereof being connected securely to a second portion P2 thereof, for example by welding.

The first portion P1 of the component PM defines a first counterweight and comprises a first internal bore AI1, which first internal bore AI1 is centred on the first axis of rotation AR1 and partially houses one of the ends PTj (here the second end PT2) by means of a first coupling.

By way of example and as shown in non-limiting manner in fig. 2, the first portion P1 of the component PM may have a circular cross section.

The second portion P2 of the component PM defines a second counterweight and comprises a second internal hole AI2, which second internal hole AI2 is centred on the second axis of rotation AR2 and receives, by means of a second coupling, the intermediate portion PI. This accommodation is partial since the subportion of this second portion P2 must be located outside the second internal bore AI2 so as to be coupleable to the first and second gear mechanisms that ensure coupling to the countershaft.

By way of example and as shown in non-limiting fig. 2, the second portion P2 of the component PM may have an elliptical cross-section.

The centers of gravity of the first weight P1 and the second weight P2 lie in a plane that includes the eccentric center of gravity of the eccentric mass (due to the presence of the eccentricity e) and is orthogonal to the first axis of rotation AR1 of the main shaft AP, which allows the overall center of gravity to be pulled back to the center. The term "eccentric mass" here refers to the planet gears of the first and second gear mechanisms and the eccentric portion of the main shaft AP (the second portion P2 located on the main shaft (AP)), as well as all the intermediate components located between these planet gears and the eccentric.

For example, the second portion P2 of the component PM may have a center of gravity located along the third axis A3, the third axis A3 being located opposite the second axis of rotation AR2 relative to the first axis of rotation AR1 to promote eccentric mass balancing. Thus, the third axis a3 is spaced from the first axis of rotation AR1 by a distance e' equal to the eccentricity e.

The first and second couplings are achieved by the second end PT2 and the intermediate portion PI of the main shaft AP being a close fit in the first and second inner bores AI1 and AI2, respectively, of the component PM. Thus, adding a weight to the main shaft AP eliminates the need for a welding operation or the use of a splined connection, pin or key. This results in a reduction in costs, a simplification of the production and the possibility of positioning by means of the internal bores AI1 and AI2, which bores AI1 and AI2 ensure the positioning of the counterweight at a predetermined position of the main shaft AP. In other words, the invention ensures a good balance and therefore a (almost total) elimination of vibrations, which avoids the generation of noise and an accelerated wear.

It should be noted that at least one of the first and second couplings may be tight. In other words, there may be only the first close coupling, only the second close coupling, or both the first close coupling and the second close coupling, as needed.

To facilitate a tight fit, the first and second couplings may be implemented, for example, via first and second stages, respectively. The first step is defined at a first interface IC11, IC12 between the first portion P1 of the component PM and the second end PT2 of the spindle AP (housed in the first internal bore AI 1). A second stage is defined at a second interface IC21, IC22 between the second portion P2 of the component PM and the intermediate portion PI of the spindle AP.

The term "stepped" is referred to herein as defining at least two bearings disposed at different radial distances. In the example shown in fig. 1 without limitation, each stage comprises only two bearings (IC11 and IC12) or (IC21 and IC 22). However, each stage may comprise more than two bearings, for example three or four.

Each step allows easy pre-positioning of the main shaft AP in the internal bores AI1 and AI2, and then final completion of the axial coupling by providing the closest contact tight fit on the bearings.

As an example, a sliding type first hierarchical bearing may be defined in the first sub-portion IC11 of the first interface and/or a sliding type first hierarchical bearing may be defined in the first sub-portion IC21 of the second interface, so that the main shaft AP may be easily pre-positioned by easily specifying the angular position of the main shaft AP. For this purpose, each first step bearing may be, for example, of the so-called H7/H6 or H7/g6 type.

In this case, it is possible to define a fastening type second stepped bearing in the second sub-portion IC12 of the first interface and/or a fastening type second stepped bearing in the second sub-portion IC22 of the second interface, in order to obtain a fastening axial positioning without the need of adding additional axial stops of the snap spring or nut type. For this purpose, each second step bearing may be, for example, of the so-called H7/m6 or H7/p6 type.

For example, a first step may be defined on the second end PT2 of the main shaft AP (received in the first bore AI 1). In a variant, however, the first step may be defined in the first internal bore AI1 housing the second end PT2 of the main shaft AP.

For another example, the second stage may be defined on the intermediate portion PI of the main shaft AP. In a variant, however, the second step may be defined in a second internal hole AI2 housing the second intermediate portion PI of the main shaft AP.

It should also be noted that in a variant of implementation, each gradation may be replaced by a monotonic variation (increasing or decreasing according to the element concerned).