FR3053428A1 - MANUAL VEHICLE GEARBOX, WITH FORK ELASTIC SHIFT AFTER BRAKING OF THE REAR WHEEL SPROCKETS - Google Patents

Abstract

A manual gearbox is fitted to a vehicle and comprises an interlocking key (C1) comprising an elastic return means (MR) placed in front of a protuberance (PRF) of a fork (F2) coupled to a braking assembly (EF). during a selection phase of the reverse gear, and arranged, when this protuberance (PRF) constrains it consecutively to the translation of its fork (F2) induced by a control finger (DC) during a phase of engagement of the reverse , to return this fork (F2) to a rest position for effective reverse gear engagement by a reverse gear (DMA).

Description

Holder (s): PEUGEOT CITROEN AUTOMOBILES SA Société anonyme.

Extension request (s)

Agent (s): PEUGEOT CITROEN AUTOMOBILES SA Public limited company.

164) MANUAL VEHICLE GEARBOX, REAR GEAR BRAKING.

WITH ELASTIC RETURN OF FORK AFTER

FR 3 053 428 - A1 (6 / d A manual gearbox equips a vehicle and includes an interlocking key (Cl) comprising an elastic return means (MR) placed in front of a protuberance (PRF) of a fork (F2 ) coupled to a braking assembly (EF) during a reverse gear selection phase, and arranged, when this protuberance (PRF) constrains it following the translation of its fork (F2) induced by a control finger (DC) during a reverse gear engagement phase, to return this fork (F2) to a rest position for effective engagement of the reverse gear by a reverse gear finger (DMA).

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MANUAL VEHICLE GEARBOX WITH ELASTIC FORK DRIVE AFTER REAR SPROCKET BRAKING

The invention relates to manual gearboxes which are called "non-synchronized reverse gear" and which equip certain vehicles, possibly of the automobile type.

A gearbox of the aforementioned type generally comprises:

- primary and secondary shafts fitted with fixed and idler gears (forward and reverse) intended to define ratios (or speeds),

- forks capable of being translated to actuate friction synchronizers which are associated with idler gears,

- a braking assembly coupled to a fork of a forward and clean gear ratio in the event of translation to induce friction of the synchronizer associated with this latter gear capable of acting on the speed of reverse gears,

- a reverse actuator responsible for moving a sliding reverse gear to mesh with reverse gears of the primary and secondary shafts, and

a passage lever provided with an interlocking key comprising, on the one hand, a passage finger responsible for acting on the forks to cause the selective translation of one of their forks, on the second hand , a clean reverse finger, if the shift lever is rotated during a reverse gear engagement phase, to act on the reverse actuator, and, thirdly, a finger proper control, in the event that the shift lever is rotated during the reverse gear engagement phase, to translate part of the braking assembly to act on the speed of the reverse gears (and more precisely brake them) to allow reverse gear to engage with the reverse finger.

In this type of gearbox, to allow the braking to be interrupted when the reverse gear finger begins to engage reverse gear, the fork, which is associated with the aforementioned synchronizer, is mounted in translation on a fixed axis and provided with a first housing in the form of a trough capable of accommodating part of a ball which is also partially housed under the stress of a spring in a second housing of this fork. Consequently, when the control finger is rotated by the shift lever during the engagement phase of the reverse gear, it causes the translation of the fork associated with the aforementioned synchronizer into its active position, by pushing a latch. the braking assembly (rotatably mounted under an elastic restoring force on this fork). This translation partially exits the ball from the first housing. Then, when the control finger finds itself released from the latch to release the i5 translation of this fork, the force exerted by the spring on this ball forces this fork to translate in an opposite direction and therefore to return to its rest position, which puts an end to braking because it no longer acts on the associated synchronizer.

When braking is complete, continuing the rotational drive

0 of the shift lever forces the reverse actuator to move a sliding reverse gear which is mounted in translation on the reverse shaft, due to the action of the reverse finger on this actuator. This movement causes it to mesh with reverse gears of the primary and secondary shafts and therefore the effective engagement of reverse gear.

As a person skilled in the art knows, billing (that is to say the ball and its two housings) induces a hard point which requires the driver to exert an additional engagement effort which harms his comfort. driving whenever the fork, which is associated with the brake assembly, is

0 used to engage a forward gear, even though this counting is only useful for selecting reverse gear. In addition, this billing is expensive and wears out relatively quickly due to its frequent use.

The invention therefore aims in particular to improve the situation.

In particular, it offers a manual gearbox, intended to equip a vehicle and comprising:

- gears defining relationships,

- forks suitable for being translated to actuate friction synchronizers associated with some of said pinions, and

a shift lever provided with an interlocking key comprising a reverse gear finger and a control finger which are clean, in the event of the drive lever being rotated during a reverse gear engagement phase , respectively to act on a reverse actuator and to translate part of a braking assembly coupled to a fork of a forward gear, to induce friction of the synchronizer associated with this latter gear capable of acting on the speed of reverse gears.

i5 This gearbox is characterized in that its interlocking key also includes an elastic return means which is suitable for being placed at least partially in front of a protuberance of the fork coupled to the braking assembly during a selection phase. of the reverse gear, and which is arranged, when this protuberance

0 constrained consecutively to the translation of its fork induced by the control finger during the engagement phase of reverse gear, to return this fork to a rest position for effective engagement of reverse gear by the finger of reverse.

Thanks to the implantation of an elastic return means on the interlocking key in a place which can only be partially in front of a protuberance of the fork associated with reverse braking when the latter is selected, not only are s frees from billing and the hard point it induces during certain forward marches. In addition, this elastic return means is only used during the phases of

0 reverse gear selection.

The gearbox according to the invention may include other characteristics which can be taken separately or in combination, and in particular:

- In a first embodiment, the elastic return means can be a torsion spring;

- In a second embodiment, the elastic return means can be a leaf spring;

- The elastic return means can be fixedly secured to the interlocking key by overmolding of at least part of the latter;

- the reverse finger and the control finger can be an integral part of the same part coupled in rotation to the passage lever;

- the fork, which is associated with the braking assembly, can also be associated with third and fourth reports.

The invention also provides a vehicle, possibly of the automotive type, and comprising a manual gearbox of the type presented above.

Other characteristics and advantages of the invention will appear on examining the detailed description below, and the appended drawings, in which:

- Figure 1 schematically illustrates, in a perspective view, part of an exemplary embodiment of a manual gearbox according to the invention, before the start of the reverse gear selection phase (or

0 gearbox neutral),

- Figure 2 schematically illustrates, in a perspective view, the gearbox of Figure 1 at the end of the reverse gear selection phase

FIG. 3 schematically illustrates, in a side view, the gearbox of FIG. 1 at the end of the reverse gear selection phase, and

- Figure 4 schematically illustrates, in a side view, the gearbox of Figure 1 at an intermediate stage of the engagement phase of reverse gear.

0 The object of the invention is in particular to provide a gearbox

Manual gearbox and reverse gear not synchronized, and intended to equip a vehicle.

In what follows, it is considered, by way of nonlimiting example, that the vehicle is of the automobile type. This is for example a car. However, the invention is not limited to this type of vehicle. It concerns in fact any type of land or sea (or river) vehicle.

Furthermore, it is considered in what follows, by way of nonlimiting example, that the gearbox BV comprises five forward gears and one reverse gear, and is associated with a gear shift grid (or gears ) called "double H" in which the first gear is in opposition to the second gear, the third gear is in opposition to the fourth gear, and the reverse gear is in opposition to the fifth gear. However, the invention is not limited to this type of arrangement of the BV gearbox. Thus, it also relates in particular to manual gearboxes with seven forward gears and one reverse gear.

There is schematically shown in Figures 1 to 4 a part of a gearbox BV type manual and non-synchronized reverse. Such a BV gearbox is intended to be coupled to a heat engine (as well as possibly an electric machine) of a vehicle via a clutch.

0 Although this does not appear in FIGS. 1 to 4, the gearbox BV conventionally comprises in particular at least one primary shaft, a secondary shaft, a reverse shaft, and friction synchronizers. As illustrated, it also includes a gearshift (or engagement) lever LP (or gear) to which is coupled a selection lever, control forks Fj, an actuator (or rocker) for reverse gear AMR, a key interlocking device C1, and a brake assembly EF.

The primary shaft is the input to the BV gearbox. It is intended to receive the engine torque via the clutch and includes several

0 fixed and idler gears, forward and reverse, intended to participate in the definition of the selectable ratios (or speeds) of the BV gearbox. The secondary shaft constitutes the output of the gearbox BV (via the differential). It is intended to receive the engine torque via the β shaft

primary in order to communicate it to the transmission shaft to which it is coupled, and for this purpose comprises several fixed and idler pinions, forward and reverse, intended to mesh certain pinions of the primary shaft in order to participate in the definition of the different selectable ratios (or speeds) of the BV gearbox.

The AMR reverse actuator (or rocker) is responsible for moving a sliding reverse gear which is mounted in translation on the reverse shaft to mesh with reverse gears on the primary and secondary shafts. It is actuated by a DMA reverse finger which is described below.

Each fork Fj is provided with a stock and is suitable for being translated by a passage finger (invisible in the figures), installed in the interlocking key Cl and secured in rotation to the passage (or engagement) lever of LP report. This translation is intended to place, during i5 of an engagement phase, the fork Fj selected in an active position in which it actuates a friction synchronizer which is associated with it and which is also associated with idler gears dedicated to at least a report.

In the example illustrated without limitation, where the gearbox BV

0 includes five forward and one reverse gear, three forks F1 to F3 are used (j = 1 to 3). The first range F1 (j = 1) is dedicated to the first and second reports, the second range F2 (j = 2) is dedicated to the third and fourth reports, and the third range F3 (j = 3) is dedicated to the fifth report. But the BV gearbox could include more than three forks or even less than three forks.

The interlocking key Cl is secured in translation to the shift lever (gear) LP and immobilized in rotation by the gearbox housing BV. The passage lever LP is translatable according to the arrow FL1

0 (see FIG. 2) by means of the selection lever to which it is fixedly secured by a crown CS, and is driven in rotation along the arrow FL2 (see FIG. 4) during a gear engagement phase (or a speed).

This interlocking key Cl is responsible for acting on the forks of the forks Fj in order to block the translation of the unselected forks. For example, it may comprise on a lower face two ribs spaced from each other by a distance chosen so as to allow the housing of a projecting upper end of the butt of a fork Fj. When a fork Fj is in its rest position (illustrated in FIGS. 1 to 3) the upper end of its stick is substantially in contact with the rightmost rib and therefore this stick can be translated to the right so that its fork Fj gains its active position (illustrated in FIG. 4) when driving in rotation counterclockwise of the shift lever LP. When a fork Fj is in its active position, its stock can be moved to the left when the passage lever LP is rotated clockwise to return to its rest position (illustrated in Figures 1 to 3).

This interlocking key C1 includes not only the aforementioned passing finger, which is responsible for selectively translating the cross-pieces of the forks Fj, but also the aforementioned reverse DMA finger, a DC control finger and an elastic return means MR.

The DMA reverse finger is coupled in rotation to the

0 passage LP. It is suitable, in the event of the LP shift lever being rotated during a reverse gear engagement phase, to act on the AMR reverse actuator so that it realizes the effective engagement of the reverse gear. .

The control finger DC is coupled in rotation to the passage lever LP. It is clean, in the event of the LP shift lever being rotated during the reverse gear engagement phase (following the reverse gear selection phase (or BV gearbox neutral)) , to translate an LF part of an EF braking assembly.

This LF part is secured to one of the forks Fj. It’s about

0 example and as shown without limitation, of a latch which is rotatably mounted on one of the forks Fj, under an elastic restoring force, and which is placed in front of the control finger DC once the latter (DC) was placed by the shift lever LP in a position illustrated in Figures 2 and 3) during the reverse gear selection phase (or gearbox neutral).

Only the LF part (here a latch) of the EF braking assembly is illustrated in FIGS. 1 to 4. This EF braking assembly is coupled to one of the forks Fj, and loaded, when its LF part is translated by the DC control finger (and therefore that it translates this fork Fj (arrow FL3 in FIG. 4)), to induce friction of the idler synchronizer, which is associated with the forward gear ratio associated with this translated fork Fj . This friction is intended to act on the speed of the reverse gear gears îo (and more precisely brake them) to allow engagement of the reverse gear by action of the reverse gear finger DMA on the actuator (or rocker) of reverse gear. AMR (arrow FL4 in Figure 4).

In what follows, it is considered by way of nonlimiting example that the braking assembly EF is coupled to the second fork F2 (here associated with the third and fourth reports). But it could be coupled with another range as far as the internal architecture of the control allows.

The LF part (here a latch) of the braking assembly EF is therefore here secured in rotation to the second fork F2.

0 It will be noted that the control finger DC and the reverse finger DMA can, for example and as illustrated without limitation, form an integral part of the same part coupled in rotation to the passage lever LP. The passing finger can also and optionally form an integral part of this last part which is then called “multifunction”.

The elastic return means MR is suitable for being placed at least partially in front of a protrusion PRF which comprises the second fork F2 (coupled to the braking assembly EF) during the selection phase of reverse gear (and therefore at the end of the translation of the passage lever LP according to the arrow FL1 in FIG. 2). This PRF protrusion is

0 defined on one face of the stock C2 of the second fork F2 which is oriented towards the part LF. It is, for example, in the form of a stud or minor axis, possibly of generally circular cylindrical shape.

This elastic return means MR is arranged, when this protrusion PRF constrains it following the translation of its second fork F2 (arrow FL3 in FIG. 4) induced by the control finger DC during the engagement phase of reverse gear, to return this second fork F2 to a rest position for effective engagement of reverse gear by the reverse gear finger DMA.

In other words, when the control finger DC translates the part LF and therefore also the second fork F2 (arrow FL3), the protuberance PRF of the latter (F2) contacts then constrains the means of the elastic return MR. Consequently, when the control finger DC ceases to act on the part LF (because it has passed over a tab PL which it includes (see FIG. 4)), the second fork F2 is found again free to translate in a direction opposite to that of arrow FL3 in FIG. 4. The elastic return means MR can therefore return this second fork F2 to its rest position (illustrated in FIGS. 1 to 3) thanks to its elasticity, which immediately puts an end to the braking effected by the EF braking assembly.

It will be noted that the protrusion PRF can either be attached to one face of the stock C2 of the second fork F2 (for example by welding,

0 bonding or screwing), or be an integral part of the stock C2 of the second fork F2, at this face.

It will also be noted that the elastic return means MR can be fixedly secured to the interlocking key Cl by molding at least part of the latter (Cl).

As shown without limitation in Figures 1 to 4, the elastic return means MR can be arranged in the form of a torsion spring. In this case, it comprises a part fixedly secured to the interlocking key Cl, and a free end EL that the protrusion PRF comes to constrain when its second fork F2 is translated along the arrow

0 FL3. It will be noted that in order to avoid the wear of this free end EL during each approaching of the PRF protrusion, it can be provided with a part made of a very resistant material and possibly overmolded.

In an alternative embodiment not shown, the elastic return means ίο MR could include a leaf spring in place of the spiral spring. For example, this leaf spring may have a general shape of J. In this case, the PRF protuberance may come to constrain the docking end of the J (that is to say its leg which is the shortest). Note that to avoid wear of this docking end during each docking of the PRF protrusion, it can be provided with a part made of a very resistant material and possibly overmolded.

With the arrangement illustrated, when the interlocking key C1 is translated by the passage lever LP (along the arrow FL1) into its position for selecting reverse gear (illustrated in FIGS. 2 and 3), the finger DC control is found behind the tab PL of the latch LF and the free end EL of the spring MR is placed in front of the protrusion PRF. Then, when the passage lever LP is rotated along the arrow FL2 during the engagement phase of reverse gear, this induces the rotation of the control finger DC. The latter (DC) will then push the tab PL of the latch LF (here to the right) and therefore induce the translation of the second fork F2 towards its active position (according to arrow FL3).

The rotation drive of the passage lever LP continuing, it

0 arrives at a time when the control finger DC is placed above the tab PL, which frees the translation of the second fork F2. The free end EL of the spring MR then exerting pressure on the protrusion PRF, the spring MR pushes the latter (PRF), and therefore its second fork F2 to the left in its rest position in which it no longer acts on the associated synchronizer. The reversing finger DMA continuing to be rotated by the shift lever LP along the arrow FL4, there comes a time when it acts on the reversing actuator AMR to cause the effective engagement of reverse gear.

Once reverse gear has been effectively engaged by

0 the action of the DMA reverse finger, the direction of rotation of the passage lever LP is reversed. Consequently, the control finger DC will rest on the upper face of the tab PL of the latch LF, which causes its tilting and thus allows the replacement of the control finger DC behind the tab PL of the latch LF which then resumes its initial position.

Thanks to the invention, there is no longer any hard point liable to harm the driver's approval each time the fork associated with the braking assembly is used to engage a forward gear. In addition, the elastic return means are only used during the reverse gear selection phases. Furthermore, the elastic return means and the protrusion are very compact, difficult to use, and inexpensive, and therefore can be added to many types of internal gearbox control commonly used.

Claims (8)

1. Manual gearbox (BV), intended to equip a vehicle and comprising pinions defining ratios, forks (Fj) capable of being translated to actuate friction synchronizers associated with some of said pinions, and a shift lever (LP) provided with an interlocking key (Cl) comprising a reverse gear finger (DMA) and a control finger (DC) which are clean, in the event of rotation of said passage lever (LP) during a reverse gear engagement phase, to act respectively on a reverse actuator (AMR) and to translate a part (PL) of a braking assembly (EF) coupled to a fork (F2) of a gear ratio front, to induce friction of the synchronizer associated with this last gear capable of acting on the speed of i5 reverse gears, characterized in that said interlocking key (Cl) also comprises an elastic return means (MR) propr e to be placed at least partially in front of a protuberance (PRF) of said fork (F2) coupled to the braking assembly (EF) during a reverse gear selection phase, and arranged, when said 2 0 protuberance (PRF) constrains it following the translation of its fork (F2) induced by said control finger (DC) during said engagement phase of reverse gear, to return this fork (F2) to a rest position for an effective engagement of reverse gear by said reverse finger (DMA). 2. Gearbox according to claim 1, characterized in that said elastic return means (MR) is a torsion spring. 3. Gearbox according to claim 1, characterized in that said elastic return means (MR) is a leaf spring. 4. Gearbox according to one of claims 1 to 3, characterized 3 0 in that said elastic return means (MR) is fixedly secured to said interlocking key (Cl) by molding at least part of the latter (Cl). 5. Gearbox according to one of claims 1 to 4, characterized in that said reverse finger (DMA) and control finger (DC) are an integral part of the same part coupled in rotation to said shift lever ( LP). 6. Gearbox according to one of claims 1 to 5, characterized 5 in that said fork (F2), associated with said braking assembly (EF), is also associated with third and fourth reports. 7. Vehicle, characterized in that it comprises a manual gearbox (BV) according to one of the preceding claims. 8. Vehicle according to claim 7, characterized in that it is of the automobile type. 1/4