Machine element or mechanism – Control lever and linkage systems – Multiple controlled elements
Reexamination Certificate
2000-04-20
2001-11-20
Fenstermacher, David (Department: 3681)
Machine element or mechanism
Control lever and linkage systems
Multiple controlled elements
C074S473360
Reexamination Certificate
active
06318206
ABSTRACT:
CROSS-REFERENCES TO RELATED APPLICATIONS
This application claims the priority of German Patent Application, Ser. No. 199 19 270.7, filed Apr. 28, 1999, the subject matter of which is incorporated herein by reference.
BACKGROUND OF THE INVENTION
The present invention relates, in general, to a shift device for use in a gear shift mechanism, and more particularly to a shift rocker for translating a shift motion, for example from a manually operated gearshift lever to a change-speed gearbox or synchronizing device, to implement a selective coupling of gearshafts.
Typically, a conventional shift rocker has two sidewalls for positive engagement in a shift sleeve which is coupled to a gear. The shift rocker is a multi-part structural element and further connected via a shift slot to a shift finger which is in fixed rotative engagement with a shift shaft. Supported in a latch contour of the shift rocker is a separate spring-loaded shift latching means to secure a precise position of the shift rocker in each shifting position. A locking lever of a locking unit is operatively connected to the shift rocker to lock the shift rocker when inactive.
U.S. Pat. No. 5,802,916, issued on Sep. 8, 1998, describes a fork-shaped shift rocker which encloses the shift sleeve, with the shift sleeve swingably supported in parallel sidewalls of the shift rocker which are interconnected by a cross member. Additional devices are arranged on different sections of the shift rocker for force introduction. Secured to the cross member in midsection of the shift rocker is a driver which is guided along a longer region axially to the outer contour of the shift rocker. The driver has an angled portion which is formed with a recess to form a shift slot for a positive engagement of the shift finger. Offset to the point of securement of the driver, the shift rocker is further provided with a radial bracket for swingably mounting a locking lever. One sidewall has a U-shaped end, with the free end configured as latch contour. Consequently, this conventional structure has different force attack points upon the shift rocker so that the shift rocker requires a relative wide wall thickness in order to possess a sufficient torsional stiffness. Apart from the resultant weight increase, the manufacture is also complicated in view of the number of individual components which have to be attached to the shift rocker separately from one another.
SUMMARY OF THE INVENTION
It is thus an object of the present invention to provide an improved shift rocker, obviating the afore-stated drawbacks.
In particular, it is an object of the present invention to provide an improved shift rocker which exhibits a high moment of resistance and has a weight-optimized configuration while yet realizing a substantially symmetrical force introduction into the shift rocker.
These objects, and others which will become apparent hereinafter, are attained in accordance with the present invention by providing a bracket of forked configuration, with the bracket having spaced apart sidewalls in parallel relation for axially displacing a shift sleeve, and an arched cross member interconnecting the sidewalls; and by providing a rail which is connected to the cross member of the bracket for introduction of force, with the rail including, directly or indirectly, a shift slot for engagement of a shift finger in fixed rotative engagement with a shift shaft, a latch contour for a separate stationary shift latching means, and a receiving member for engagement of a locking lever of a locking unit to inhibit a shifting movement of the shift rocker when the shift rocker is inactive.
The configuration and disposition of the rail reinforces the bracket and thereby the overall moment of resistance of the shift rocker. The multiple functionality of the rail, by which a central force introduction into the shift rocker is realized, provides for a symmetrical force introduction, for example onto both sidewalls of the shift rocker. In addition, the provision of the rail, preferably a prefabricated rail, further reduces manufacturing costs and optimizes the weight.
According to another feature of the present invention, the rail has an inverted U-shaped configuration when secured to the cross member of the bracket. In the assembled state, the rail extends parallel to a longitudinal axis oriented through receiving bores of the sidewalls, whereby the rail has a free end which projects beyond the cross member at a distance to a cross member portion that is angled in the direction of the sidewalls.
Suitably, the receiving member of the rail is a recess or opening in the form of a punch-out hole for so receiving and securing the locking lever as to permit a swinging of the locking lever. The recess has a section extending transversely to the longitudinal axis of the shift rocker for guiding an end of the locking lever. A cylindrical pin mounted to the locking lever is received in a section of the recess which is oriented in the direction of the longitudinal axis.
According to another feature of the present invention, the rail supports at one end that is distant to the attachment area of the rail to the cross member, a flat member, e.g. flat iron, which partially projects out beyond the rail end. Impressed in the outwardly directed end of the flat member is the latch contour. The flat member defines a longitudinal axis and has a portion which is angled transversely to the longitudinal axis and inclined, in the assembled position, towards the center of the shift rocker at an angle of ≧20° with respect to the rail, with the shift slot being formed in the angled portion of the flat member for positive engagement of a shift finger.
Suitably, the bracket, the rail, and the flat member can be made in a cost-efficient manner by a non-cutting process, for example a deep-drawing process or a punching process.
The components, bracket, rail and flat member, are connected non-detachably to one another, preferably by a welding process. The lengths of the welding seams as well as the position of the welding seams between the rail and the bracket of the shift rocker may be, optionally, individually configured.
The design and disposition of the rail as U-section results in a significant reinforcement of the shift rocker in radial direction, i.e. direction of selection, as well as axial direction, i.e. direction of shift. At the same time, the inverted U-shaped rail enhances the reception of the locking lever and other components via which a force is introduced into the shift rocker.
A shift rocker according to the present invention displays a sufficient stiffness to ensure a precise, permanent shift of the gear shift mechanism.
REFERENCES:
patent: H295 (1987-07-01), Numazawa et al.
patent: 5471893 (1995-12-01), Newbigging
patent: 5802916 (1998-09-01), Ebinger et al.
patent: 6038938 (2000-03-01), Szczepanski et al.
patent: 6122983 (2000-09-01), Hoffman
patent: 24 56 962 A1 (1975-06-01), None
patent: 27 50 275 A1 (1979-05-01), None
patent: 07 94 364 A2 (1997-09-01), None
Kramer Klaus
Trissler Arnold
Feiereisen Henry M.
Fenstermacher David
Ina Walzlager Schaeffler OHG
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