CN104603507A - shift unit - Google Patents

Abstract

A shifting unit 1 is proposed, which has a shifting element 2 with a locking contour 3 and a shift locking device 4 for the position locking of the shifting element 2. The shift locking device 4 has a housing 10 and a locking element 5, wherein the locking element 5 is prestressed against the locking contour 3 by means of a spring 6, and has a stroke limiting mechanism 7, which limits the elastic deflection of the locking element 5 such that the maximum stroke H of the locking element 5 is smaller than the height difference H between the locking recess 8 and a side wall 21 connected to the locking recess 8.

Description

shift unit

technical field

The invention relates to a shift unit. The shifting unit has: a shifting element with a locking contour; and a shift lock with a housing and a locking element for position locking of the shifting element, wherein the locking elements are opposed by means of a spring Preload on the locking profile.

Background technique

Such shifting units are used in particular in motor vehicle transmissions in order to be able to fix shiftable or displaceable elements in defined positions.

For this purpose, a spherical section of the sleeve of the shift lock or at least one spring-preloaded ball can engage in a recess of the component to be fixed, so that the component assumes the desired position and when a sufficiently large It can only be moved out of this position again with a certain shifting force.

Such a gearshift locking device is known from DE 41 03 465 C2. The shift lock has two sleeve-shaped elements which are arranged coaxially with one another. The sleeve-shaped part is formed as a carrier element, which serves as an opening for receiving a further sleeve-shaped part serving as a locking element. The locking element is axially displaceable relative to the carrier element, since the receiving openings in the cylindrical outer circumference of the carrier element and of the locking element form sliding guides.

On the end facing away from the carrier element, the locking element carries a ball which can engage in a recess in the component for locking. The locking element is prestressed with respect to the carrier element by means of a helical spring.

From DE 103 59 067 there is known another gearshift locking device suitable for use without rolling balls. The circular locking element is held on the housing by an edge which limits the travel of the locking element during springback.

Such a shifting unit is known from DE 10 2005 053 542 A1. In order to ensure that the shift locking device moves on the shifting element only in the region of the locking contour and that no impermissible relative movements occur, the shifting element of the shifting unit has a stop for the housing of the locking device. stopper. Although the stop prevents excessive axial movement, it must be machined from the material of the shifting element or must be connected thereto in a non-detachable manner. In both cases this represents increased manufacturing outlay.

Contents of the invention

The present invention is therefore based on the object of proposing a shifting unit with a locking mechanism for limiting a linear movement and/or an angular displacement, summarized below as a relative movement, which can be produced in an inexpensive manner. .

This object is achieved by a shifting unit according to claim 1 . According to the invention, the maximum possible travel of the locking element is coordinated with the locking contour of the shifting element, so that disengagement of the locking contour is reliably prevented. A separate stop on or on the shifting element, for example cooperating with the housing of the shift lock device, is therefore not necessary and therefore does not have to be produced. The production of the shifting element from tubes or flat profiles is thus simplified.

According to the invention, the locking contour has a contour with a locking recess in the position of the shift end. If the shift locking device is not moved back into the neutral channel from the shift end position, but is moved past the shift end point, the locking element is strongly loaded by the locking contour, so that the stroke limiting mechanism stops against the stop and prevent further movement. The height difference to be overcome, viewed from the locking recess, must therefore be greater than the remaining path, which is normally also springable by the prestressed locking element in the locking recess.

In order to limit the stroke, the shift lock has a stroke limiting mechanism. Suitably, the travel limiting mechanism is not formed by the spring itself, so that the spring is not forced to move "hindered" and thus not overloaded. In a first refinement, the travel limiting means is the locking element itself or a component of the switch locking device which is acted upon directly by the locking element. The travel limiting mechanism cooperates with a stop which is part of the shift lock or part of a component which accommodates the shift lock. The stop is formed in a particularly simple manner by a part of the housing of the shift lock device, for example its base or an inwardly protruding projection in its wall.

According to the invention, the stroke limiting mechanism prevents excessive elastic run-out of the locking element. It is not necessary to ensure that the locking element is retained on the housing.

In one refinement, the shift locking device has a locking element in the form of a ball which is seated in a ball cap of a locking pin which is movable back and forth by means of the ball. With respect to the rear side of the ball, the locking bolt has a shoulder that acts as a travel limiting mechanism. The shoulder is so long that it abuts against the housing of the shift lock device after a maximum permissible spring runout predetermined by the type of locking contour.

The locking element is held in the housing in a loss-proof manner. For this purpose, for example, the locking element is pot-shaped, wherein the pot wall can be tapered or shrunk. The can edge can also be tapered or the free can end opposite the can bottom can be partially covered by a part of the housing. The spring can be supported on the bottom of the tank. The locking element is arranged on the open end opposite the tank bottom. The tank wall can be formed as a cylindrical sleeve or can be composed of segmented, planar tank wall sections. Alternatively, the tank wall can consist of a plurality of individual sections spaced apart from one another. The bottom of the tank need not be designed to be flat.

The locking element can be designed as a solid sphere or as a hollow sphere. The locking element can also be designed as a post. Alternatively, the locking element is a sleeve or another, as round as possible, spring-loaded component. The spring is a spring element which pretensions the locking element against the housing also without the action of an external force. A force introduced from the outside onto the locking element moves said locking element in the direction of the tank bottom. The spring is preferably designed as a mechanical spring, in particular a helical compression spring.

In one embodiment of the invention, the housing has stops on its tank wall. The stop protrudes from the tank wall and projects laterally inwardly from the tank wall extending substantially in the direction of the elastic run-out of the locking element. In this case, a lateral protrusion is to be understood as any protrusion. In particular, no right angles are required to form the stop. The stop can be formed as a material thickening or have the same thickness as the tank wall. For this purpose, the tank wall can be provided with inwardly directed recesses.

In a preferred development, the entire housing is pot-shaped and in one piece.

In a further development of the invention, the housing is produced from sheet metal using molding techniques. The housing can be deep-drawn and the stop for the stroke limiting mechanism can be formed by one or more lugs pointing away from the tank wall.

For ventilation of the locking device, the locking device can be provided with one or more openings. In a variant, the locking device has a central opening on its pot bottom, which is formed as a transition point and is adapted to the thread radius of the compression helical spring. If the opening has an edge pointing inward, the spring is held in a locked manner.

In one embodiment of the invention, the shifting element is designed as a selector lever, as a selector shaft or as a selector rail. The locking contour is either introduced into the shifting shaft, for example by machining, or it is fixedly connected thereto as a component produced separately from the shifting element. For this purpose, the locking contour can be arranged on a shifting sleeve surrounding the shifting element or be fastened as a plate-shaped part on the shifting element.

If the shifting element formed as a shifting rail can only be moved linearly, the locking contours can be formed by a plurality of grooves which are aligned substantially parallel to one another and run perpendicularly to the direction of movement of the shifting rail, said grooves optionally being It is produced, for example by stamping, in the same production step as the shifting element. The groove depth of at least the outer groove relative to the contour pointing away from the locking contour is greater than the residual travel that the locking element can carry out in the mounted state. The individual slots are separated by a bulge which is smaller than the remaining travel, so that the shift lock can be moved into any slot.

In particular, the locking contour can be formed in the shifting shaft as the shifting element by a plurality of circumferential locking recesses in the form of annular grooves. In this case, radial rotation cannot be prevented by the locking contour. Alternatively, the locking contour has only individual cavity-shaped locking recesses, which can also form a stop against undesired movements in the circumferential direction. In this case, the locking contour covers only a partial corner region of the shifting element.

In a further embodiment, the shifting unit has a shift fork which is arranged on the shift element. The selector lock is fixedly connected to the selector fork, so that a movement of the selector fork over the shifting element causes the locking contour to move out. Preferably, the shift fork is coupled to the shifting element via a guide tube. In a refinement, the guide tube can have, for example, a radially oriented extension in the form of a flange, on or in which the shift locking device is arranged. It is particularly simple if the shift locking device is pressed into the extension.

To sum up, the invention provides a shifting unit in which the locking and anti-twist and anti-removal functions are brought about individually by the shift locking device instead of by a plurality of components. Thus, even without an external locking mechanism, the shift locking device cannot be unscrewed or moved out of the locking contour, so that the shift fork can always be positioned in a defined manner in the transmission.

Description of drawings

Hereinafter, the present invention will be explained in detail based on examples. Figures 1-4 show:

FIG. 1 shows a longitudinal section through a first shifting unit according to the invention with a schematically illustrated shift lock device,

FIG. 2 shows a schematic diagram of the individual shifting strokes according to FIG. 1 ,

FIG. 3 shows a first shift locking device for the shifting unit according to FIG. 1 , and

FIG. 4 shows a second shift lock arrangement for the shifting unit according to FIG. 1 .

Detailed ways

FIG. 1 shows a shifting unit 1 with a selector lever as shifting element 2 and a shift locking device 4 with a locking element 5 . The shift locking device 4 is prestressed against the locking contour 3 , which is machined into the shifting element 2 . The locking contour 3 has three locking recesses 8 following one behind the other in the shifting direction, into which the locking element 5 can be locked. A locking side wall 21 , which merges into the outer diameter of the selector lever without forming a bulge beyond the outer diameter of the selector lever, is connected to the corresponding outer locking recess 8 .

The shift lock 4 is fixedly connected to the shift fork 13 . For this purpose, the shift fork 13 has, in addition to its fork-shaped base body, a guide sleeve 14 , via which the shift fork is coupled to the fixedly arranged selector lever and is mounted on the selector lever. Guided by vertical movement. The guide sleeve 14 has an extension 15 oriented transversely to its main direction of extent, into which the housing 10 of the shift lock device 4 is pressed. The shift lock device 4 is therefore connected via the wall 12 of its housing 10 to the selector fork 13 .

3 and 4 show two different shift lock devices 4 for the shifting unit 1 according to FIG. 1 . The locking elements 5 in the form of balls are each held in a loss-proof manner in the deep-drawn housing 10 from sheet metal. The balls are acted upon and pretensioned by a spring 6 designed as a helical compression spring. Its helical diameter corresponds to the inner diameter of the pot, so that the shift lock device 4 has a compact design. With its one end, the spring 6 is supported on the bottom 11 of the pot-shaped housing 10 and, with its other end, it acts on a locking bolt 16 arranged between the spring 6 and the locking element 5 . The locking bolt 16 has the shape of a spherical cap facing the locking element 5 , which accommodates the ball. On the rear side, the locking bolt 16 has a step 17 in the form of an annular shoulder, on which the spring 6 is supported. The step 17 is delimited inwardly by a rod 18 which points towards the bottom 11 of the housing. The diameter of the rod 18 corresponds approximately to the inner diameter of the spring 6 , so that it is also guided on the inside and cannot be tilted. The rod 18 has a blind hole 19 pointing towards the bottom 11 , which reduces the weight of the locking bolt 16 .

In addition to holding the ball as locking element 5 and the guide spring 6 , the locking pin 16 assumes a further function: said locking pin with its underside end 20 which can stop at the tank bottom 11 together with the bottom of the housing 10 11 forms the stroke limiting mechanism 7. The possible maximum stroke h of the locking element 5 is determined by the length of the rod 18 , the rod length being at least selected such that the spring 6 moves without hindrance.

FIG. 2 shows the correlation between the maximum stroke h of the locking element and the shaping of the locking contour 3 . The locking contour 3 , as described in FIG. 1 , has three locking recesses 8 arranged one behind the other in a straight line in the form of a cavity, which are delimited on the outside by side walls 21 . Currently, the side wall 21 is directly connected to the outer locking recess 8 . The locking recess 8 is formed as a cut-out of the locking lever with a reduced diameter. The selector lever has a shaft diameter D in its non-diameter-reduced cross-section. In the present example, the diameter of the selector lever is reduced to the value d in the locking recesses 8 , each of which has the same depth.

Due to the arrangement and design of the shift locking device 4 , the maximum travel h in the position of the locking element 5 in the locking recess 8 and the locking pin 16 in the stop at the base 11 is smaller than the difference in diameter D-d between the positions. As a result, the shift locking device 4 can only be moved relative to the shifting element 2 in the shift position region 9 , which is part of the locking contour 3 . In order to ensure a stable stop, the height difference H to be overcome, which is formed here by the diameter difference D-d, exceeds the maximum stroke h of the shift lock device 4 by 20%. Thus, the shift lock 4 always remains in a defined position on the shifting element 2 .

List of reference signs

1 shift unit

2 shift elements

3 lock profile

4 Shift lock device

5 locking elements

6 springs

7 Stroke limiting mechanism

8 locking recess

9 Shift position area

10 shell

11 bottom

12 walls

13 shift fork

14 Guide sleeve

15 stretching department

16 locking bolt

17 steps

18 poles

19 blind holes

20 end of bottom side

21 side wall

h Maximum stroke

H height difference

d diameter

D shaft diameter

Claims (8)

1. A shift unit (1), having - shifting element (2) with locking profile (3) and - a shift locking device (4) with a housing (10) and a locking element (5) for position locking of the shifting element (2), wherein the locking element (5) is The spring (6) is preloaded relative to the locking profile (3), - It is characterized in that the shift lock device (4) has a stroke limiting mechanism (7), and the stroke limiting mechanism limits the elastic jump of the locking element (5), so that the maximum The stroke (h) is smaller than the height difference (H) between the locking recess (8) and the side wall (21) connected to said locking recess (8). 2. The shifting unit according to claim 1, characterized in that, the stroke limiting mechanism (7) is configured as a bolt that loads the locking element (5), and the bolt is arranged in a reciprocating manner. In a pot-shaped housing (10) with a bottom (11) and a top wall (12), wherein the pin stops against the bottom (11) or against the top wall (12) in order to limit the stroke )superior. 3. The shifting unit according to claim 1 or 2, characterized in that the shifting element (2) is designed as a shifting shaft with locking recesses (8), wherein the maximum shaft diameter (D) is reduced Even though the diameter (d) at the deepest point of the locking recess (8) is still greater than the maximum stroke (h) of the locking element (5). 4. The shifting unit according to any one of the preceding claims, characterized in that the shift lock device (4) and the shift fork (13) arranged on the shift element (2) ) are fixedly set to each other. 5. The shifting unit according to claim 4, characterized in that the shift fork (13) has a guide sleeve (14) for guiding on the shifting element (2), the guide The sleeve has a radially oriented extension (15) for receiving the shift lock (4). 6 . The shifting unit as claimed in claim 1 , characterized in that the locking contour ( 3 ) covers only a partial corner region in the cross section of the shifting element ( 2 ). 7. The shifting unit according to claim 1, characterized in that, the shift locking device (4) has a locking pin (16), which is arranged between the locking element (5) and the Between the springs (6), wherein the locking pin (16) forms the travel limiting mechanism (7). 8. The shifting unit according to claim 1, characterized in that the maximum stroke is less than 2 mm in an installed state.