DE102011009831A1 - Device for locking e.g. switching shaft of automatic or automated gear box of motor car, has locking element connected with switching element for locking or releasing element and releasably fixed with interposition of ball by plunger - Google Patents

Abstract

The device (10) has a locking element connected with a switching element (1) e.g. switching shaft, for selectively locking or releasing the switching element. The locking element is releasably fixed with interposition of a ball (3) by a plunger (2). The ball directly cooperates with the switching element, and the plunger is actuated by an electromagnet. The switching element or the locking element has a radial recess (4), which cooperates with the ball for locking the switching element. The locking element is pressed against an outer contour of the switching element by a spring (5).

Description

The invention relates to a mechanical locking of a switching element in transmissions, in particular in automatic or automated transmissions, which are remotely switched by means of so-called shift-by-wire or remotely controlled. The speed steps are not controlled manually by means of a shift stick, but the shift stick can be hydraulically operated by means of a hydraulic arrangement to realize the shift-by-wire function. Furthermore, it is known to hydraulically actuate the parking lock of a transmission. As switching elements serve, for example, switching shafts or cylinder piston of an actuating element. The invention also relates to a transmission with such a device.

Such means of shift-by-wire actuated gear require a lock to suppress unwanted switching movements for safety reasons in case of failure of an example hydraulically actuated actuator. Known latches use pawl mechanisms and electric magnets, where the lever design is very difficult to design because of the small lifting work in conjunction with the high actuating forces of the actuator in case of failure. Furthermore, such locking mechanisms require close tolerances of the components as well as well-known friction coefficients of the sliding parts. The known lever mechanisms are therefore expensive due to a complicated and tight tolerance geometry in connection with required high surface quality in the field of functional surfaces in their production. In addition, the spatially curved ratchet lever require the most demanding manufacturing processes. For the levers, it is also necessary to provide leg springs that are difficult to assemble and require a high degree of friction. Since the pawls can not cover all error cases, in particular in the case of hydraulic shift-by-wire controllers, complicated and complicated securing in the form of a pressure reducing valve in front of the module is required. Such an error case may be an unwanted cylinder actuation against the pawl at full system pressure, whereby the module is destroyed. Object of the present invention is to provide a simple, robust and space-saving mechanical locking a switching element for a means of shift-by-wire operated transmission.

The object is achieved by a device for locking a switching element of a transmission of a motor vehicle, wherein the switching element is lockable in at least one switching position, the device having a the switching element for selectively locking or releasing the switching element associated latching element, wherein the locking element with the interposition of at least one Ball can be fixed by means of a plunger and is detachable.

The task is thus solved in principle by the application of a blocking ball mechanism. The invention is characterized in that instead of the pawls, a ball mechanism is provided. In this case, a guided ball fall into corresponding recesses of a moving switching element, so the shift shaft or its actuating cylinder and thus clear the way for a magnetic pin which holds the ball locked in a locked position.

In a Weitzerbildung of the invention, the switching element with the interposition of at least one ball by means of a plunger can be fixed and released, wherein the ball interacts directly with the switching element and serves as a latching element.

Preferably, the plunger is actuated by means of an electromagnet.

In a further development of the device according to the invention, the switching element or the latching element has a recess, a groove or a constriction, which cooperates with the ball for locking the switching element. Said recess, groove or constriction can be provided with such a contour that self-locking occurs.

Said output is also achieved with a transmission having a switching position-having switching element for selecting speed ranges or gears of the transmission, which is provided with an embodiment of the device described above for locking the switching element.

The locking of the switching element according to the invention by means of a ball mechanism has a number of advantages. Thus, the balls may be arranged coaxially about a cylinder piston of a hydraulic actuator or coaxially about a switching shaft. In this way, a rotary latch is shown. Instead of complicated spatial ratchet lever turned parts and cheap to be provided as bulk material balls can be used. Thus, the lock according to the invention can be made low even with only small quantities needed. Due to the closed circular structure or the circular cross section of the locked switching elements such as switching shaft or cylinder piston of the actuator, a very good material utilization is achieved, so that high locking forces in a small space are transferable and manageable. Furthermore, if necessary, by means of appropriate configuration of the contour of the recess, groove or constriction in the shift shaft or in the cylinder piston self-locking can be adjusted.

In the following, embodiments of the invention will be explained with reference to the accompanying drawings. Show

1 a sectional view through an inventive device for locking a switching element;

2 a sectional view through a further embodiment of the device according to the invention for locking a switching element by means of a locking element and

3 a sectional view through an embodiment of the inventive device for locking a switching element.

The inventive device for locking and releasing a switching element is based on the 1 to 3 explained in more detail. The same or similar parts are provided with the same reference numerals.

In 1 is a device 10 for selectively fixing and releasing one around an axis 6 rotatable switching element 1 , For example, a shift shaft for adjusting gears or shift stages of a transmission, shown. The switching element 1 has radially arranged on its outer circumference recesses 4 ' on, which for receiving the end of a locking element 1' serve. The possibility of twisting the switching element 1 is indicated by a curved double arrow. The locking element 1' is by means of a spring 5 against the outer contour of the switching element 1 pressed. When turning the switching element 1 can the locking element 1' perform an axial movement, this always in contact with the surface of the switching element 1 maintains. The axial displaceability of the locking element 1' is indicated by a double arrow. The locking element 1' can be according to the requirement in its lower position, so if its end in one of the recesses 4 ' is immersed, blocked. This is a ball 3 by means of a downward movement of a plunger 2 laterally into a substantially cylindrical detent element 1' located groove 4 pushed. As long as the pestle 2 remains in its lower position, is the locking element 1' and thus also the switching element 1 blocked. The possibility of movement of the ram 2 is indicated by a double arrow. The plunger movement is performed by means of an electromagnetic drive, not shown.

2 shows a similar embodiment of the device according to the invention 10 , wherein here no lockable switching element is shown. The main difference to the embodiment according to 1 is that the leadership and movement of the plunger 2 not parallel but perpendicular to the guide and movement of the locking element 1' is. For clarification is in the right part of 2 whose left part is shown in a sectional side view.

In the embodiment of the 3 is dispensed with an additional locking element, so that the ball 3 itself serves as a locking element, wherein the ball as a counterpart to the blocking of the switching element 1 serving recesses 4 directly in the switching element 1 are introduced. Thereby, that a multiplicity of the recesses 4 on the circumference of the switching element 1 are provided, different locking positions of the switching element 1 be realized. Between the turn electromagnetically actuated plunger 2 and the switching element 1 may need several balls 3 be arranged to establish a certain distance between the components.

LIST OF REFERENCE NUMBERS

1

switching element

1'

locking element

2

tappet

3

Bullet

4

Recess, groove

4 '

Recess, groove

5

feather

6

axis of rotation

10

contraption

Claims (6)

Contraption ( 10 ) for locking a switching element ( 1 ) of a transmission of a motor vehicle, wherein the switching element ( 1 ) can be locked in at least one switching position, with a the switching element ( 1 ) for selectively locking or releasing the switching element ( 1 ) associated latching element ( 1' ), characterized in that the detent element ( 1' ) with the interposition of at least one ball ( 3 ) by means of a plunger ( 2 ) is fixable and detachable. Contraption ( 10 ) for locking a switching element ( 1 ) of a transmission of a motor vehicle, wherein the switching element ( 1 ) is lockable in at least one switching position, characterized in that the switching element ( 1 ) with the interposition of at least one ball ( 3 ) by means of a plunger ( 2 ) is fixable and detachable, wherein the ball ( 3 ) directly with the switching element ( 1 ) cooperates and serves as a latching element. Contraption ( 10 ) according to claim 1 or 2, characterized in that the plunger ( 2 ) is actuated by means of an electromagnet. Contraption ( 10 ) according to one of the preceding claims, characterized in that the switching element ( 1 ) or the locking element ( 1' ) a recess, a groove or a constriction ( 4 ), which for locking the switching element ( 1 ) with the ball ( 3 ) cooperates. Contraption ( 10 ) according to claim 4, characterized in that the recess, the groove or the constriction are provided with such a contour that self-locking occurs. Transmission with a switch positions having switching element ( 1 ) for selecting gears or gears of the transmission, with a device ( 10 ) for locking the switching element ( 1 ) according to any one of the preceding claims.

Images