DE102006003245B4 - Power transmission joint for a switching device of a motor vehicle transmission, a switching device for such a motor vehicle transmission, and a method for producing a power transmission joint - Google Patents

Abstract

Power transmission joint (1) for a switching device of a motor vehicle transmission, with a joint cage (11) which is connected to a first transmission element (3) and in which a bushing (27) is held on the inside, in which a pin (25) of a second transmission element ( 5) is rotatably mounted, and with a damping element (31) which is arranged between the bushing (27) and the joint cage (11) for damping gear-side shift shocks or vibrations, the damping element (31) carrying the bushing (27) and in the joint cage (11) is supported, and wherein the bush (27) is mounted in a through hole (29) of the damping element (31), characterized in that the bush (27) has a radial play (S1) in the through hole (29) of the damping element (31) is mounted, and that the bush (27) is formed on the front side with a guide plate (37) which is free of play in the joint cage (11) in a longitudinal direction (7) of the power transmission joint (1) rt, whereby only a translational movement of the bushing (27) in the longitudinal direction (7) of the power transmission joint (1) is possible, while a rotational movement in terms of a torsional security of the bushing (27) is avoided, and that the guide plates (37) have axial stops form which allow axial movement of the bushing (27) via an axial play (S2) in the damping element (31).

Description

The invention relates to a power transmission joint for, in particular, a switching device of a motor vehicle transmission according to the preamble of the patent claim 1 , a switching device for a motor vehicle transmission according to claim 14, and a method for producing a power transmission joint according to claim 15.

Such a switching device of a motor vehicle has a manually operable shift lever. The shifting movements of the shift lever initiated by the driver of the vehicle are transmitted by means of transmission elements to a shift shaft on the transmission side for shifting gears or gear ratios.

Such transmission members can be cables or linkages which are connected via a generic power transmission joint, as shown in FIG DE 39 32 815 A1 is revealed. This power transmission joint has a joint cage for connection to a first transmission element, ie a lever on the transmission side. In the joint cage, a bush designed as a sliding block is held, in which a pin of a second transmission member, ie a shift rod, is rotatably mounted. A damping element is arranged between the bushing and the joint cage, which dampens force peaks during a synchronization process or gear-side shift shocks or vibrations during a shift process. The damping takes place only in the switching direction of the shift lever or the longitudinal direction of the power transmission joint. In contrast, the bushing is mounted without play in the selection direction of the shift lever or in the transverse direction of the power transmission joint without damping in order to give the vehicle driver a precise feeling of selection.

To hold the socket in the joint cage, a detent spring is provided as an additional retaining member, which is latched on the outside with the joint cage and presses the socket or the sliding block with its wedge surfaces under preload against corresponding surfaces of the joint cage. The production of this power transmission joint with the additional holding member is associated with a high manufacturing effort and is therefore cost-intensive.

From the further publication DE 41 16 996 A1 a shifting device is known in which a shift shaft mounted in a transmission housing is connected to a shift finger via a hub. The selector shaft is connected to the hub via a leaf spring, by means of which gear-specific stimuli and impulses are eliminated. From the DE 43 34 166 C1 a circuit for a motor vehicle change-speed transmission is known. In the circuit, a transmission input shaft is connected to the forked head of a transmission link. A flexible bearing layer is inserted in the forked head of the transmission link. From the DE 198 13 721 A1 a connecting element is known which has a joint housing in which a bushing is held. A damping element is inserted between the socket and the recess of the joint housing, which dampens vibrations during vehicle operation.

From the DE 10 2004 014 813 A1 a generic power transmission joint is known which has a damping element which is arranged between a radially inner bearing bush and a radially outer joint cage. The damping element carries the bush and is held in the joint cage. From the DE 102 16 903 B4 a connection device for an actuating cable on a slave, in particular a drawbar eye, is known. From the DE 199 27 055 A1 another cable fastening is known. From the DE 10 2004 013 193 A1 a connection device for an actuating cable to a slave is known.

The object of the invention is to provide a power transmission joint for, in particular, a shifting device of a motor vehicle transmission, a shifting device and a method for producing a power transmission joint, which has a simple structure in terms of reducing components.

This object is achieved with the features of claim 1, claim 14 or claim 15. Further developments of the invention are disclosed in the respective subclaims.

According to the invention, no additional holding member is required to hold the bushing in the joint cage, but rather the bushing is carried solely by the damping element in the joint cage. An additional holding member can therefore be saved in the sense of a reduction in components, whereby the manufacturing effort and also the required installation space is correspondingly reduced.

According to the invention, the socket is mounted in a through hole of the damping element. With regard to an advantageous damping characteristic of the damping element and a stress-free and thus low-wear mounting of the socket in the damping element, according to the invention, the socket is mounted in the damping element via an annular gap with play. Due to the defined “softness” or damping characteristics of the damping element that can be achieved, the transmission has more time for a synchronization process available without the driver needing more time to shift into gear. This also significantly reduces the transmission of vibrations from any type of transmission into the passenger compartment. The damping properties of the switching device can be further improved if the gear-side lever is designed with additional inertial masses.

According to the invention, the power transmission joint is designed so that the damping element is only subjected to pressure. In this way, materials can also be used for the damping element which would tear if subjected to tensile stress, for example a conventional rubber material or elastomer material. It is therefore possible to dispense with an expensive, process-insecure, tensile connection between a joint cage made as a plastic part and a damping element made of rubber material. With such a tensile rubber-plastic connection, a primer would have to be applied to the respective connection surfaces in advance.

When the bushing according to the invention is supported in the damping element with play, the bushing is designed with an axial stop or height stop on the front side, which allow a slight axial movement of the bushing in the damping element. Thus, the bushing can be supported in the axial direction as well as in the radial direction via a clearance, whereby vibrations and / or shifting jolts of the gear shift lever can be achieved with respect to the stationary joint cage, without the bushing in the cage being able to tilt. The damping element itself preferably forms a counterstop against which the axial or vertical stop of the bushing can come into contact.

The bushing is designed, preferably at the end face, with at least one guide plate, which is located in the joint cage in a longitudinal direction of the power transmission joint, i. H. is guided in the switching direction, essentially free of play. This prevents a rotational movement or a movement of the bushing in the damping element in the selection direction. Thus, the damping characteristic can only be designed with regard to a pressure load in the switching direction, since stressing the damping element with rotational forces and / or transverse forces is excluded.

From a manufacturing point of view, it is particularly advantageous if the bushing is formed from at least two bushing parts which can be introduced into the joint cage from opposite sides and can be connected to one another. In this way, the end face geometry of the bushing can be designed independently of a passage cross section of the joint cage.

It is preferred if the socket is held in the rest state free of pre-tension and / or without contact with respect to the joint cage, whereby mechanical stresses between the socket and the joint cage or between the socket and the damping element can be reduced, which increases the service life of the damping element. The bushing and / or the joint cage can be made of a solid plastic.

So that the damping element can safely support the bushing with radial and / or axial play, it is advantageous if the damping element is connected to the joint cage firmly or without play. In this context, the damping element can be connected to the joint cage in a frictional, non-positive or positive manner. A form-fit connection has proven to be particularly advantageous in which the joint cage can be designed on the inside with a nose-like cross-sectional constriction which can engage in a correspondingly circumferential annular groove of the damping element.

Particularly favorable damping properties are achieved if the damping element is not designed in the form of a sleeve, but rather as a compact block of strong material, preferably made of an elastomer material. A damping element designed in this way can largely fill the cage space delimited by the joint cage and be in contact with the inner sides of the joint cage over a large area on the circumference. For the damping properties, it is essential if the damping element is designed with at least one free cavity, which is preferably arranged in the switching direction between the socket and the cage. It is particularly preferred if a cavity is arranged between the bushing and the joint cage on both sides in the switching direction.

Outstanding damping properties are made possible if, in addition to the at least one free cavity in the damping element, the bushing is arranged to be movable in the longitudinal direction or switching direction via the above-mentioned annular gap. With the at least one cavity and the annular gap within the damping element, at least two spaced free cavities are provided, which are separated from one another by solid material sections and thus enable almost complete damping of the gear-side shift shocks and / or vibrations.

According to a particular embodiment, the installation location of the power transmission joint is in the Shifting device of the motor vehicle transmission is selected such that a shift cable connected in particular directly to a manually operable shift lever is used as the first transmission element. The shift cable can be connected via the power transmission joint to the second transmission element, designed as a gear shift lever, which is preferably connected directly to a shift shaft mounted in the gear. In this case, a corresponding selector cable can be in engagement with the gear shift lever via a reversing lever in order to transmit a shift movement in the selection direction.

Due to the above-described arrangement of the power transmission joint close to the transmission, gear-side shift shocks, vibrations and / or oscillations can be dampened at an early stage without these being able to spread further in the vehicle.

In a method according to the invention for producing the power transmission joint, the joint cage can first of all be placed as a base body, preferably in an injection molding tool. The damping element with its through hole for the bushing can then be injected directly into the cage. To hold the bushing in the joint cage, the bushing is then carried by the damping element alone.

An exemplary embodiment of the invention is described below with reference to the accompanying figures.

• 1 in einer Seitenschnittansicht ein Kraftübertragungsgelenk, das einen Getriebeschalthebel mit einem schalthebelseitigen Seilzug verbindet;
• 2 in einer Ansicht von oben das Kraftübertragungsgelenk; und
• 3 einen vergrößerten Teilschnitt entlang der Linie I-I aus der 1.

Show it:

• 1 in a sectional side view, a power transmission joint that connects a gear shift lever with a shift lever-side cable;
• 2 in a view from above the power transmission joint; and
• 3 an enlarged partial section along the line II from FIG 1 .

In the 1 is a power transmission joint as part of a switching device for a motor vehicle transmission 1 shown that a first transmission link 3 , an example of a shift lever-side cable or shift cable with a second transmission element 5 , for example a gear shift lever, connects. The Indian 1 indicated cable is guided to a shift lever, not shown. In contrast, the gear shift lever is connected to a shift shaft mounted in the transmission, which can carry a shift finger, by means of which shift rods for shifting gears or gear ratios can be displaced. It is known that switching movements in the switching direction can be achieved by manually operating the switching lever 7th along the power transmission joint 1 as well as in dialing direction 9 across the power transmission joint 1 be transferred to the control shaft. The shift lever movement is in the, in the 1 indicated dialing direction 9 that are perpendicular to the switching direction 7th extends, transmitted directly to the gear shift lever via a selector cable (not shown).

Like in the 1 is shown is the power transmission joint 1 with a frame-like joint cage 11 formed, the outside an elongated hollow cylindrical connector 13th has, the end face with radially adjustable locking jaws 15th each with an internal toothing 17th is trained. The locking jaws are on their outsides 15th from an axially displaceable sleeve 19th surrounded that in the 1 the locking jaws 15th with their internal gears 17th presses against a corresponding external toothing of the cable to lock it. The sleeve 19th is about a coil spring 21 in her, in the 1 shown position pressed. For releasing the cable from the power transmission joint 1 is the sleeve 19th against the spring force of the coil spring 21 to move, causing the locking jaws 15th come out of engagement with the cable.

The gear shift lever on the gearbox side is for connection to the power transmission joint 1 with a forked lever head 23 formed, the power transmission joint between the two parallel fork cheeks 1 is arranged. A bearing pin forming the hinge axis 25th penetrates the fork cheeks and a socket 27 of the power transmission joint 1 . The by the bearing pin 25th formed joint axis extends according to the 1 in the dialing direction 9 .

The socket 27 extends within the joint cage 11 through a through hole 29 a compactly designed damping element 31 , for example an elastomer block or elastomer body. This acts as a damping element between the socket 27 and the joint cage 11 arranged. The damping element 31 is about its outer circumferential groove 33 in a form-fit connection with a corresponding, bead-like cross-sectional constriction 35 of the joint cage 11 . In addition, there is the damping element 31 over a large area in contact with the inside of the joint cage 11 so that the damping element 31 and the joint cage 11 are also frictionally connected.

In order to achieve good damping characteristics, the massive damping element fills it 31 the one from the joint cage 11 limited cage space and are in the damping element 31 free voids 36 or cavity-like pockets are provided. These are in the longitudinal direction or Switching direction 7th between the socket 27 and the joint cage 11 arranged and formed with opposing cavity walls which are spaced apart from one another _{via free spaces a 1} , a _2. The free cavities 36 as well as the through hole 29 of the damping element 31 are about solid material sections 34 separated from each other.

Like in the 3 shown is the socket 27 over an annular gap with a first game S ₁ in the radial direction in the through hole 29 of the damping element 31 stored. So that the socket 27 despite the radial play S ₁ reliable in the joint cage 11 is held, this is on the front side with guide plates 37 educated. The opposite guide plates 37 the socket 27 extend radially outward in the manner of a flange and form axial stops or height stops, which according to FIG 1 about a second game S ₂ axial movement of the bushing 27 in the damping element 31 allow.

In addition, the guide plates are 37 the socket 27 with their moving lengthways 7th Extending narrow sides essentially free of play in contact with the respective upper and lower side edges of the inner sides of the joint cage 11 or slightly spaced from it. As a result, there is only a translational movement of the socket 27 longitudinal 7th of the power transmission joint 1 allows, while a rotational movement in terms of a torsional security of the socket 27 is avoided. With such a rotational movement of the bush 27 in the through hole 29 of the damping element 31 could about shear forces on the damping element 31 are transmitted, whereby its damping characteristics are impaired with a predetermined identifier and, in the worst case, the damping element 31 can be destroyed.

For overload protection of the damping element 31 are the guide plates 37 the socket 27 with their transverse to the longitudinal direction 7th extending narrow sides according to the 2 each over a longitudinal distance b from inside stops of the joint cage 11 spaced. The longitudinal distance b thus corresponds to a maximum damping path of the socket 27 in the longitudinal direction or switching direction 7th in the joint cage 11 .

According to the 1 and 2 is the joint cage 11 formed on its opposite side edges each with a step 38 in which the two guide plates 37 are longitudinally guided. The step 38 ensures that the socket 27 with their guide plates 37 even without a damping element 31 captive in the joint cage 11 remains. The functionality of the power transmission joint 1 can therefore be maintained even if a damaged damping element 31 away from the joint cage 11 replaces.

The top and bottom of the cushioning element 31 protrudes somewhat over the step 38 of the joint cage 11 out. When the bushing moves axially 27 in the damping element 31 therefore form the top and bottom of the damping element 31 Counter stops for the axial and / or height stops 37 the socket 27 . The socket 27 is therefore free of contact with the joint cage 11 stored.

As from the 1 showing is the socket 27 in two parts with two bush parts connected to one another in the axial direction 39 , 41 educated. The socket parts 39 , 41 are connected to one another on their facing sides via a latching or screw connection, not shown in detail.

During the operation of the motor vehicle, when the gears or gear ratios are shifted, shift shocks and vibrations occur on the transmission side, which are transmitted to the power transmission joint via the gear shift lever 1 transmitted and by means of the damping element 31 as well as through the cavity-like pockets and the radial play S ₁ provided free spaces in the joint cage 11 of the power transmission joint 1 can be largely eliminated. The attenuation takes place due to the in the 1 and 2 shown longitudinal guide of the socket 27 in the edge-side gradations 38 of the joint cage 11 only in the switching direction 7th . In the dialing direction extending transversely to it 9 is the socket 27 in contrast, essentially free of play in the joint cage 11 stored, whereby only a translational movement of the socket 27 in switching direction or longitudinal direction 7th in the damping element 31 is made possible.

Due to the preload-free mounting of the bush 27 in the damping element 31 becomes the damping element 31 only used during switching operations. Without exception, this involves compressive stress, which means that the damping element is worn out early due to tensile stress 31 is avoided.

List of reference symbols

1

Power transmission joint

3

first transmission link

5

second transmission link

7th

Switching direction, longitudinal direction

9

Dialing direction, cross direction

11

Joint cage

13th

Connector

15th

Locking jaws

17th

Internal gearing

19th

Sleeve

21

Coil spring

23

forked lever head

25th

Bearing pin, bearing journal

27

Rifle

29

Through hole

31

Damping element

33

Circumferential groove

34

Solid material sections

35

Cross-sectional constriction

36

free voids

37

Guide plates, axial stops

39, 41

Socket parts

S ₁

Radial play

S ₂

Axial play

a ₁ / a ₂

free spaces between opposite cavity sides

b

In-line spacing

Claims (15)

Power transmission joint (1) for a switching device of a motor vehicle transmission, with a joint cage (11) which is connected to a first transmission element (3) and in which a bushing (27) is held on the inside, in which a pin (25) of a second transmission element ( 5) is rotatably mounted, and with a damping element (31) which is arranged between the bushing (27) and the joint cage (11) for damping gear-side shift shocks or vibrations, the damping element (31) carrying the bushing (27) and in the joint cage (11) is supported, and wherein the bush (27) is mounted in a through hole (29) of the damping element (31), characterized in that the bush (27) has a radial play (S ₁ ) in the through hole (29 ) of the damping element (31) is mounted, and that the bushing (27) is formed at the end with a guide plate (37) which is free of play in the joint cage (11) in a longitudinal direction (7) of the power transmission joint (1) leads, whereby only a translational movement of the bushing (27) in the longitudinal direction (7) of the power transmission joint (1) is enabled, while a rotational movement in terms of a torsional security of the bushing (27) is avoided, and that the guide plates (37) axial stops form that allow axial movement of the bushing (27) via an axial play (S ₂ ) in the damping element (31). Power transmission joint (1) according to Claim 1 , characterized in that the bush (27) is formed from at least two bush parts (39, 41) which can be mounted in the joint cage (11) from opposite sides. Power transmission joint (1) according to one of the preceding claims, characterized in that the bushing (27) is held in the joint cage (11) in a preload-free and / or contact-free manner. Power transmission joint (1) according to one of the preceding claims, characterized in that the damping element (31) is connected to the joint cage (11) in a fixed and / or play-free manner. Power transmission joint (1) according to Claim 4 , characterized in that the damping element (31) is frictionally, non-positively and / or preferably positively connected to the joint cage (11). Power transmission joint (1) according to Claim 5 , characterized in that the joint cage (11) is formed on the inside with a nose-like cross-sectional constriction (35) which is in positive connection with a corresponding circumferential recess (33) of the damping element (31). Power transmission joint (1) according to one of the preceding claims, characterized in that the damping element (31) is designed as a compact block, preferably made of an elastomer material. Power transmission joint (1) according to one of the preceding claims, characterized in that the damping element (31) at least partially fills a cage space delimited by the joint cage (11). Power transmission joint (1) according to one of the preceding claims, characterized in that the damping element (31) is circumferentially in contact with the inner sides of the joint cage (11) over a large area. Power transmission joint (1) according to one of the preceding claims, characterized in that the damping element (31) for setting a damping characteristic preferably in the longitudinal direction (7) of the joint (1) with at least one free cavity (36) between the joint cage (11) and the socket (27) is formed. Power transmission joint (1) according to Claim 10 , characterized in that the at least one free cavity (36) over solid material sections (34) is spaced from the longitudinal sides and / or the through hole (29) of the damping element (31). Power transmission joint (1) according to one of the preceding claims, characterized in that the first transmission element (3) is a cable, in particular a shift cable connected to a manually operated shift lever, and the second transmission element (5) is a gear shift lever which is directly connected to a gearshift lever in the motor vehicle transmission bearing shift shaft is connected. Power transmission joint (1) according to Claim 12 , characterized in that the gear shift lever is connected to a selector cable which adjusts the gear shift lever (5) in the selection direction (9). Shifting device for a motor vehicle transmission with a power transmission joint (1) according to one of the preceding claims. Method for producing a power transmission joint (1) according to one of the Claims 1 to 13th , in which a damping element (31) is firmly connected to a base body forming a joint cage (11), and then a bushing (27) is passed through a through hole (29) of the damping element (31) and carried by the latter.

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