GB1565175A

GB1565175A - Gearbox control assembly

Info

Publication number: GB1565175A
Application number: GB3673/78A
Authority: GB
Original assignee: Societe Anonime de Vehicules Industriels et dEquipements SA SAVIEM
Current assignee: Societe Anonime de Vehicules Industriels et dEquipements SA SAVIEM
Priority date: 1977-02-15
Filing date: 1978-01-30
Publication date: 1980-04-16
Also published as: FR2380473A1; DE2804697B2; FR2380473B1; IT1107095B; IT7867300A0; SE7801591L; DE2804697C2; DE2804697A1

Description

(54) GEARBOX CONTROL ASSEMBLY (71) We, SOCIETE ANONYME DE VEHICULES INDUSTRIELS ET D'E QUIPEMENTS MECANIQUES (S.A.V.I.E.M.), a French body corporate, of 8, quai Leon Blum, 92152 Suresnes, France, do hereby declare the invention for which we ray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: The present invention relates to a gearbox control assembly.

A previously proposed gearbox control assembly comprises a pivotally mounted actuating lever which is urged by resilient means towards a position corresponding to the gearbox neutral condition. The resilient resistance to be overcome to select a higher gear from neutral is different from the resilient resistance to be overcome to select from neutral a lower gear, such as reverse gear. The lever is displaceable in a gate and is fixed on a carrier by means of two further, parallel springs urging it towards a position in the gate, which corresponds to the neutral position. One end of the actuating lever directly actuates sliders carrying the control forks for displacement of the sliding gears of the gearbox synchromesh mechanism and it is of advantage for the lever construction to be as simple as possible, for the purpose of imparting thereto a high degree of control precision and a degree of mechanical strength which is sufficient, for actuating the sliders.

According to one aspect of the invention, there is provided a control assembly for a gearbox, comprising an actuating lever mounted for pivotal control movement about a pivot axis, and resilient means for urging the lever towards a lever position which corresponds to a gearbox neutral position, the line of action of said resilient means on said lever being displaced axially of the pivot axis relative to the longitudinal axis of the actuating lever in said neutral position and the resilient resistance to be overcome to select a higher gear from neutral being different from the resilient resistance to be overcome to select from neutral a lower gear.

Embodiments of a control assembly according to the present invention will now be described by way of example with reference to the accompanying drawings, in which: Figure 1 is a view in cross-section of a part of a motor vehicle gearbox, with the control assembly, Figure 2 is a plan view of the control assembly of Figure 1.

Figure 3 is a view of the assembly in cross-section taken along line III-III in Figure 1.

Figure 4 is a view corresponding to Figure 1 showing an alternative embodimer t of the control assembly.

Figure 5 is a view of the Figure 4 assembly in cross-section taken along line V-V in Figure 4 Figure 6 is a perspective view of a selector gate for selecting actuating movements of the sliders, of the gearboxes of Figures 1 to 3 or Figures 4 and 5.

A gearbox control assembly as shown in Figures 1. 2 and 3 includes the actuating lever 1 comprising an upper portion la, a lower portion ib, and a pivot ic between the two portions la and ib. The upper portion la is in the form of a tube provided with an actuating handle (not shown). The lower portion ib is disposed on a carrier casing member or portion 2, on which the pivot ic is also mounted. The casing member 2 is rigidly connected at its base 3 to a main casing 4 of the gearbox, by means of screws (not shown). The lower portion 1b of the lever 1 also passes through a selector gate 5 which is screwed into the casing 4 and which is shown in greater detail in Figure 6. The lower portion 1b of the lever 1 terminates in a rounded enlarged portion or finger 6 which is selectively co-operable directly with recessed head portions 7a of sliders 7, 7' which are disposed in one or two parallel planes and which carry control forks 8 and 8' for displacement of the synchromesh sliding gears, and a control fork or lever 10 for controlling a sliding pinion p for selecting reverse gear. For this purpose, the lever 10 carries an actuating lug or finger 9. The lever 10 is pivoted on the casing member 2 by means of an actuating rod 11 of a light switch (not referenced) for lighting reversing lamps.

The pivot 1c of the lever 1 is formed by a spindle 12 which is fixed in the lever 1 non-rotatablv relative thereto. The spindle 12 carries two movable sliders 13 and 14 disposed at respective ends of the spindle.

Each slider 13 and 14 comprises a slidable bearing member of which one face f is engaged by a resilient return means formed by a coil spring 15 and 16 respectively disposed in recesses 17 and 18 in the casing member 2. The springs 15 and 16 urge the spindle 12 upwardly in Figure 1, to return the lever 1 to the neutral position of the gearbox. The springs 15 and 16 which are of different lengths have different mechanical characteristics and their lines of action, which here are formed by the centre axes X and X' of the respective springs, are offset relative to the longitudinal axis of the actuating lever in the neutral position axially of the axis of the spindle 12, by virtue of the springs 15 and 16 being disposed at respective sides of the lever 1. This arrangement makes it possible easily to differentiate between the resistance to be overcome to select a higher gear from the neutral position, and the resistance to be overcome to select reverse gear from the neutral position. Thus, when the upper end of the lever 1 is displaced towards the right in Figure 1, the spring 15 disposed in the recess 17 is compressed, and the finger 6 at the lower end of the lever 1 engages the recessed head portion 7a of the slider 7', to selecting a transmission ratio corresponding to one of the forward gears.

When displacement of the upper end of the lever 1 towards the left in Figure causes compression of the spring 16, whose stiffness is greater than that of the spring 15, the finger 6 engages the recessed head portion of the lever 10 which controls the movement of the sliding reverse pinion p.

During the movements of the upper end of the lever 1 towards the right or towards the left from its central or neutral position, the sliders 13 and 14 respectively bear alternatively against abutments formed by the inner face of a closure cover 30 through which passes the lever 1, and the spindle 12 slides freely in its sliders 13 and 14. In order to facilitate the pivotal movement of the lever 1 during its movements for selecting the respective transmission ratios, which movements occur about an axis ZZ' which is perpendicular to the plane of Figure 1 and which is shown in Figure 3, the abovementioned abutments on the inner face of the closure cover 30 comprise pivot edges 31 and 32 which are perpendicular to the spindle 12. The pivot edges 31 and 32 are advantageously formed by stamping in the cover 30, and the assembly 30, 31, 32 is attached to the casing member 2.

Figures 4 and 5 show an alternative form of the assembly described above with reference to Figures 1 to 3. Some members in the Figures 4 and 5 embodiment are identical to corresponding members of the assembly shown in Figures 1 to 3 and will therefore not be described again, such members being indicated by the same reference numerals as in Figures 1 to 3 but additionally preceded by the numeral 4. Pivot 41c of lever 41 comprises spindle 412 which at its ends is engaged in the fixed prismatic or squaresection bearing members 413 and 414 which rest on a shoulder 415 in the casing member 42. The lever 41 is journalled at the position of pivot 41c on the spindle 412 and can assume an inclined position relative to the spindle 412, by pivoting in the plane of Figure 4, against the resilient resistance of a spring assembly; this spring assembly comprises at least one main spring 416 which is disposed in a recess 420 in the upper portion 41a of the lever 41 and which pushes against the spindle 412 a pushrod member 421. The line of action X of the spring 416 is displaced axially of the spindle 412 relative to the axis Y of the lever 41, by a distance d. The pivot 41c is also formed by an elongate opening 422 in the lever 41. The spindle 412 passes through the opening 422 whose shape is shown in Figure 5 and which has a vertical plane of symmetry disposed in the plane of Figure 4, as shown by line A in Figure 5; the plane of symmetry thus extends lengthwise of the lever 41. The diameter of the spindle 412 is less than the elongate dimension of the opening 422 i.e. as measured in the plane of symmetry A, so that the lever 41 is displaceable in the plane of Figure 4, by pivoting about a second axis 0 which is perpendicular to the plane of Figure 4 and which is formed by the point of contact between the pushrod member 421 and the spindle 412. The offset position of the line of action X of the spring 420, relative to the axis Y of lever 41, therefore makes it possible, as in the preceding embodiment of Figures 1 to 3, to differentiate between the resilient resistance which has to be overcome to select reverse gear from the neutral position, and the resilient resistance which is to be overcome to select a forward transmission ratio, from the neutral position. In addition, pushing the lever 41 down makes it possible to operate selector sliders which are disposed at different levels in the gearbox.

The control assembly shown in Figure 4 also has a closure cover 430 which immobilises the preferably prismatic or square bearings 413 and 414 on the casing member 42, and resilient washers 423 which are disposed between the lever 41 and the respective bearing members 413 and 414, to urge the lever 41 towards a central position in its neutral position.

Figure 6 shows a selector gate 5 through which the lever 1 or 41 extends, for guiding the lever in the appropriate paths to engage with the selector sliders 7, 7' or 47, 47'.

It will be seen from the foregoing description that the pivot spindle 12 and the pivot edges 31 and 32 in the embodiment of Figures 1 to 3, and the pivot spindle 412 and the axis 0 in the embodiment of Figures 4 and 5, make it possible easily to satisfy operating requirements in respect of selection and engagement of the different transmission ratios of the gearbox. The abovementioned pivot arrangements 12, 31. 32 and 412, therefore operate in the manner of a conventional gearbox lever pivot while being inexpensive.

Of course, the resilient means for urging the actuating lever 1 towards a lever position which corresponds to a gearbox neutral position may engage the lever 1, or the spindle 12, 412, or both lever and spindle.

WHAT WE CLAIM IS: 1. A control assembly for a gearbox.

comprising an actuating lever mounted for pivotal control movement about a pivot axis, and resilient means for urging the lever towards a lever position which corresponds to a gearbox neutral position, the line of action of said resilient means on said lever being displaced axially of the pivot axis relative to the longitudinal axis of the actuating lever in said neutral position and the resilient resistance to be overcome to select a higher gear from neutral being different from the resilient resistance to be overcome to select from neutral a lower gear.

2. An assembly according to claim 1 wherein said resilient means comprises two springs disposed in respective recesses in a casing portion, wherein each spring bears against a respective slider. wherein said pivot axis comprises a spindle movably mounted in the sliders, and wherein at least in the neutral position of the lever each slider is urged by the respective springs against pivot edge means extending perpendicular to said pivot axis.

3. An assembly according to claim 2 wherein said pivot edge means is stamped in a closure cover through which passes the actuating lever and which is fixed to said casing portion.

4. An assembly according to claim 1 wherein said return means comprises at least one main spring which is disposed in a recess in the lever and which applies its spring force to a pivot spindle providing said pivot axis, and wherein the pivot spindle passes through an elongate opening in the lever, the opening having its elongate dimension in a plane of symmetry which extends lengthwise of the lever, and the diameter of the pivot spindle being less than said elongate dimension.

5. An assembly according to claim 4 wherein bearing members disposed at respective ends of the pivot spindle rest on a shoulder arrangement of a casing portion carrying the lever and are immobilised thereon by a closure cover.

6. An assembly according to claim 4 or claim 5 wherein said at least one main spring urges a pushrod member against the said spindle providing said pivot axis, the contact between the pushrod member and said spindle defining a second pivot axis for the lever, which second axis is perpendicular to the first-mentioned pivot axis.

7. A control assembly for a gearbox, comprising a support member, a pivot spindle carried by the support member, a control lever carried on the spindle and pivotal about the axis of the spindle. the lever also being pivotal on the spindle about a second axis in the same plane as and perpendicular to the spindle axis, and resilient means engaging the lever and/or the spindle and urging the lever towards a lever position which corresponds to a gearbox neutral position. the line of action of said resilient means on the lever and/or spindle being displaced axially of the spindle axis from the longitudinal axis of the actuating lever in said neutral position and the resilient resistance to be overcome to select a higher gear from neutral being different from the resilient resistance to be overcome to select from neutral a lower gear.

8. A control assembly for a gearbox, substantially as hereinbefore described with reference to Figures 1 to 3 or Figures 4 and 5 of the accompanying drawings.

9. A motor vehicle gearbox including a control assembly according to any one of the preceding claims.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. to be overcome to select a forward transmission ratio, from the neutral position. In addition, pushing the lever 41 down makes it possible to operate selector sliders which are disposed at different levels in the gearbox. The control assembly shown in Figure 4 also has a closure cover 430 which immobilises the preferably prismatic or square bearings 413 and 414 on the casing member 42, and resilient washers 423 which are disposed between the lever 41 and the respective bearing members 413 and 414, to urge the lever 41 towards a central position in its neutral position. Figure 6 shows a selector gate 5 through which the lever 1 or 41 extends, for guiding the lever in the appropriate paths to engage with the selector sliders 7, 7' or 47, 47'. It will be seen from the foregoing description that the pivot spindle 12 and the pivot edges 31 and 32 in the embodiment of Figures 1 to 3, and the pivot spindle 412 and the axis 0 in the embodiment of Figures 4 and 5, make it possible easily to satisfy operating requirements in respect of selection and engagement of the different transmission ratios of the gearbox. The abovementioned pivot arrangements 12, 31. 32 and 412, therefore operate in the manner of a conventional gearbox lever pivot while being inexpensive. Of course, the resilient means for urging the actuating lever 1 towards a lever position which corresponds to a gearbox neutral position may engage the lever 1, or the spindle 12, 412, or both lever and spindle. WHAT WE CLAIM IS:

1. A control assembly for a gearbox.