Connecting unit

Abstract: The present invention relates to a connecting unit for the transmission of pulling movements to one end of at least one bowden cable, in particular for a parking brake of a vehicle. The present invention further relates to a method for establishing a connection between a bowden cable and a pulling element for the transmission of pulling movements, as it is preferably used during the assembly of parking brakes in vehicles. The connecting unit comprises a support with at least one opening for the mounting of the connecting unit, a pulling element with at least one receptacle for the end of the at least one bowden cable and a guiding element, where the end of the at least one bowden cable can engage the receptacle, and the guiding element is arranged between the at least one opening of the support and the at least one receptacle. The guiding element deflects the end of the at least one bowden cable under a movement in direction of the receptacle through the at least one opening of the support to the side to engage the receptacle.

Description: 1. Technical field The present invention relates to a connecting unit for the transmission of pulling movements to at least one bowden cable, in particular for a parking brake of a vehicle. The present invention further relates to a method for establishing a connection between a bowden cable and a pulling element for the transmission of pulling movements, as it is preferably used during the assembly of parking brakes in vehicles. 2. The prior art Bowden cables serve in many fields of technology for transmitting movements from one place to another. In motor vehicles for example the transmission is often controlled by a shift lever whose movements are transmitted by means of one or more bowden cables. A further typical field of use for bowden cables is the parking brake of a car. In this case the movement of a lever is transmitted by two bowden cables to the brakes usually mounted to the two rear wheels to achieve a simultaneous operation of the two brakes. For transmitting the pulling movements to a bowden cable a thickening is arranged at the end of the steel cable typically used for bowden cables. The receptacle for the bowden cable, for example of a brake lever, usually comprises a small hole through which the cable extends. The diameter of the hole is such that the cable, but not the thickening at the end of the cable, can fit through the hole. When the receptacle moves into a direction opposite to the direction into which the cable extends, a pulling movement is transmitted to the cable. This kind of connection between receptacle and cable according to the prior art causes during the assembly of bowden cables, in particular in the automotive field a considerable amount of work since the cable has to be manually passed through the small hole in the receptacle before the other end can be connected with the desired part (transmission, brake, etc.). The difficulties caused thereby are to be further explained in the following with reference to the example of a parking brake in a car as it is for example shown in the DE 195 46 931: When a parking brake is assembled, the two braking cables for the simultaneous operation of the two brakes are to be mounted to a so-called equalizer compensating a different wear of the brake linings and/or small differences in the length of the two cables. The equalizer is via a further single braking cable connected to the brake lever. In order to avoid the accumulation of dirt or corrosion such an equalizer can be arranged inside a housing. During assembly at first the two braking cables have to be manually arranged in the corresponding receptacles of the equalizer before the housing can be mounted. The overall procedure therefore requires several manual steps and thus causes considerable costs. Further, it is necessary that the equalizer and the ends of the braking cables can be easily accessed and seen from the outside. Depending on the location where the equalizer is arranged, it will during assembly be necessary to rotate and/or lift the complete car to allow an easy access and view of the equalizer and the two braking cables. Further, general concepts for the connection of a single bowden cable and a lever are disclosed in the EP 0 311 346 and the EP 0 857 881. The document EP 0 857 881 A1 shows a device for the connection of the cable end fitting of a bowden cable to a control lever. The device consists of a cap comprising a socket for the cable end fitting. The cap further has guide surfaces for the cable end fitting, taking it from the base of the cap and into the socket. The socket lies at the bottom of a recess inside the cap so that the cable end fitting is guided automatically into it when a traction is applied to the cable once it has passed over the guide surfaces. Since the cap includes the guide surfaces for the cable end fitting, these guide structures increase the weight of the parts to be moved and effect the shape of the cap. It is therefore the problem of the present invention to provide an improved connecting unit for the transmission of pulling movements to one or several bowden cables which can be assembled in a simple step, i.e. the connection between the end of the bowden cable and corresponding receptacle can be achieved without having to access or to see the connecting unit, wherein the weight of the movable part is minimized and the shape of the movable part is not negatively affected. According to a further aspect, it is the problem of the present invention to provide a simple and easy method for connecting a pulling element and a bowden cable for the transmission of pulling movements to the bowden cable, wherein an improved connecting unit is used. 3. Summary of the invention These problems are solved by a connecting unit with the features of independent claim 1 and a method with the features of independent claim 12 . In detail the present invention relates to a connecting unit for the transmission of pulling movements to one end of at least one bowden cable, in particular for a parking brake of a vehicle, where the connecting unit comprises a support for mounting the connecting unit with at least one opening, a movably arranged pulling element with at least one receptacle for the end of the at least one bowden cable and a guiding element, where the end of the at least one bowden cable can engage the receptacle and where the guiding element is stationary arranged at the support between the at least one opening of the support and the at least one receptacle. The guiding element deflects the end of the at least one bowden cable to the side under a movement in the direction of the receptacle through the at least one opening of the support for an engagement with the receptacle. In the connecting unit according to the invention the cable is not inserted from the front side but slides, coming from the back side, preferably sideways through a slit into the receptacle. This is achieved by the sideways deflection of the end of the cable by the guiding element, leading to an elastic bending of the cable which causes the cable to spring back into the slit of the receptacle once it has passed the guiding element. As a result, the bowden cable can "automatically" engage the receptacle in one step by a simple pushing of the end through the opening in the support in the direction of the receptacle. Since the guiding element itself inserts the end of the bowden cable under such a movement into the slit, the complete procedure can be carried out "blind", i.e. without the need to be able to see the connecting unit from the outside. The end of the braking cable in the direction of the receptacle can also be moved by pushing at the other end of the bowden cable so that there is no need to directly access the connecting unit. The complete connecting unit can therefore be arranged inside a closed housing which does not need to be opened for the assembly of the bowden cable. This allows a pre-assembly to a great extent which considerably shortens the time for the assembly of a vehicle at the assembly line. According to a preferred embodiment the guiding element comprises a groove-like guiding surface for deflecting the end of the at least one bowden cable. By this shape of the guiding surface it is assured that the end of the bowden cable is reliably deflected by the guiding element. Preferably, the groove-like guiding surface comprises a slit-like recess, in which the at least one cable extends after the end of the cable has engaged the at least one receptacle. In a particularly preferred embodiment the pulling element comprises a second receptacle with a slit and a second bowden cable extends essentially parallel to the first bowden cable through a second opening in the support where the guiding element deflects one end of the second bowden cable under a movement in the direction of the second receptacle so that it is inserted into the slit of the second receptacle. For the use in a parking brake of a vehicle the pulling element is preferably provided as an equalizer and the two bowden cables as braking cables. The equalizer preferably contacts in the disengaged state of the parking brake the front side of the guiding element. Preferably, the two receptacles for the two braking cables are shaped as essentially hemispherical recesses in the equalizer, which are arranged in corresponding recesses of the front side of the guiding element, when the brake is disengaged. Thus, the positions of these two parts with respect to each other are fixed. The subject matter of the dependent claims are further preferred embodiments of the connecting unit according to the invention. According to a further aspect, the invention relates to a method for establishing a connection between at least one bowden cable and a movably arranged pulling element for transmitting pulling movements from the pulling element to the at least one bowden cable where the method comprises the steps of moving the end of the at least one bowden cable in the direction of a receptacle in the pulling element, deflection of the end of the bowden cable from the direction of movement by a stationary arranged guiding element under the elastical bending of the bowden cable and elastical spring-back of the end of the at least one bowden cable into the receptacle through a slit in the receptacle. 4. Short description of the drawing In the following detailed description a presently preferred embodiment of the present invention is shown with reference to the drawing which shows: Fig. 1: A perspective front view of a preferred embodiment of the connecting unit according to the invention in the assembled state; Fig. 2: A perspective rearview of the connecting unit of Fig. 1; Fig. 3: A perspective view of the connecting unit during assembly of bowden cable 1; Fig. 4: A perspective rearview of the connecting unit of Fig. 1 in the assembled state with a disengaged parking brake; Fig. 5: A top view of the connecting unit of Fig. 1; Fig. 6: A side view of the connecting unit of Fig. 1. 5. Detailed description of the invention The particularly preferred embodiment of the invention described in the following is used as a part of a parking brake system of a vehicle. However, it has to be understood that the invention can be used wherever a pulling movement is to be transmitted to one or several bowden cables. With reference to Fig. 1 the connecting unit comprises a support 10 having a horizontal and vertical section (cf. Fig. 6). The support serves preferably for mounting the connecting unit to the vehicle. To this end several further (not shown) borings can be provided for mounting screws or the like. Conceivable is also to glue the support to the frame of the vehicle. As a protection against dirt and/or corrosion the complete connecting unit can be arranged inside a housing (not shown) having on its one side an opening for the cable 34 and on the other side two openings for the two cables 1, 2. If needed, the support 10 can be an integral part of the housing. In the vertical section of the support preferably two circular openings 11, 12 are arranged through which the two cables 1, 2 extend. Via these two cables the brakes usually arranged at the rear wheels of the vehicle (not shown) are operated. At the rear side of the support 10 the outer sheath of the cables can be mounted (not shown), directly or via two tubes 3. The cables comprise at their respective front ends thickenings 4, 5 which are arranged in corresponding hemispherical receptacles 32a, 32b when the connecting unit is assembled (cf. Fig. 2). The hemispherical receptacles are part of an equalizer 30. They comprise each an outwardly to the side directed slit 33a, 33b. If the complete equalizer 30 is forwardly pulled (dashed arrow in Fig. 1), by means of the further bowden cable 34 (cf. Fig. 3) connected to the lever of the parking brake (not shown) this pulling movement is simultaneously transmitted to the two cables 1, 2. Since the cable 34 is attached to the equalizer 30 by means of a tee 31, the relative position of the two receptacles 32a, 32b with respect to the pulling direction can be changed by a rotation around the vertical part of the tee to compensate different lengths of the cables 1 or 2 or different wear of the brake linings of the two brakes (not shown). Thus it is assured, that both rear wheels are braked with the same force. Since the functioning of an equalizer is well-known to a person skilled in the art, it is not further discussed in the following. Between the rear side of the equalizer 30 and the vertical section of the support 10 the guiding element 20 is arranged according to the invention. As can be seen in particular in the top view of Fig. 5 this part has essentially the shape of an obtuse triangle where the "tip" contacts the vertical section of the support 10 between the two openings 11 and 12. The opposite front side is directed to the rear side of the equalizer 30. When the parking brake is disengaged, the rear side of the equalizer 30 directly contacts the front side of the guiding element 20 (cf. Figures 3, 4). As can be derived from Figs. 1 to 4 the two sides of the guiding elements 20 comprise each preferably a guiding surface 23, 21 shaped like a groove. In the sections of the guiding surfaces 23, 21 directed to the equalizer 30 preferably slit-like recesses 22, 24 are provided in the groove-like guiding surfaces 23, 21 extending in the direction of the respective cable 1 or 2. By means of the connecting unit according to the invention it is during assembly, as explained in the following, possible by means of simple pushing at the rear ends (not shown) of the two cables 1, 2 to arrange the two thickenings 4, 5 in the corresponding receptacles 32a, 32b of the equalizer 30: To this end the thickenings 4, 5 are pushed at the ends of the cables 1, 2 (either simultaneously or one after the other) from behind through the openings 11, 12. Fig. 3 shows the situation when the end of the cable 1 has just passed the opening 11. Under a further movement of the thickening 4 it hits the inclined guiding surface 23 which deflects it from its original direction of movement (cf. small black arrow in Fig. 3). Due to this deflection the cable 1 is elastically bent. Under a further movement the thickening 4 slides along the groove-like guiding surface 23. Due to the preferred grooved shape of the guiding surface 23 a sliding of the thickening 4 from the guiding surface 23 in a downward or upward direction is avoided. During assembly the brake lever is in the position of a disengaged brake so that, as already mentioned, the rear side of the equalizer 30 directly contacts the front side of the guiding element 20 (cf. figure 3). Therefore, when the thickening has passed the front side of the guiding element 20 it is introduced by the springy force of the cable 1 into the slit 33a on the side of the receptacle 32a. In this situation the cable 1 extends in the slit-like recess 24 of the guiding groove 23 (cf. Figures 1, 2 and 4, 5). By pushing from its rear end the thickening 5 of the cable 2 is in the same way introduced into the receptacle 32b. When the braking lever is now operated, the pulling movement of the equalizer 30 is transmitted to the two cables 1, 2. The connecting unit according to the invention and the method according to the invention allow to arrange the front ends of the cables 1 and 2 in the corresponding receptacles 32a, 32b by a simple pushing at their respective rear ends without the need of a direct access and/or view of the connecting unit. Preferably, the two receptacles 32a, 32b in the equalizer 30 are hemispherically shaped (cf. Fig. 2) to provide a better rest for the thickenings 4,5. In this case a short pulling movement is necessary subsequent to the pushing movement at the rear end of each cable 1, 2 to secure the thickenings 4, 5 in the hemispherical recesses of the receptacles 32a, 32b. Preferably, circular recesses 26 are provided on the front side of the guiding element 20 (cf. Figs. 1 and 5) in which the mentioned hemispherical recesses 32 of the equalizer 30 are arranged, when the brake is disengaged, whereby the relative position of the equalizer 30 and the guiding element 20 are fixed. It is to be understood that by providing several guiding surfaces at the guiding element 20 also other numbers of cables can be connected with corresponding receptacles. Further, it is clear that with a single guiding surface and the corresponding receptacle a connecting unit according to the invention can be provided for a single bowden cable. Finally, a person skilled in the art understands that the present invention can also be used in other fields (for example ship building, for the operation of the rudder) than the automotive field. Apart from the cables 1 and 2 which are preferably made out of steel cables, plastic materials like Polyamide No. 6 or different metal alloys are used. For the equalizer and the support which are subjected to the greatest mechanical stress preferably metal is used whereas the guiding element is preferably produced by injection molding of a plastic material to reduce the weight and costs.

Claims: Connecting unit for the transmission of pulling movements to an end (4) of at least one bowden cable (1), in particular for a parking brake of a vehicle, comprising: a. a support (10) with at least one opening (11) for mounting the connecting unit; b. a movably arranged pulling element (30) with at least one receptacle (32a, 32b) for the end (4) of the at least one bowden cable (1), where the end (4) of the bowden cable (1) can engage the receptacle (32a, 32b); c. a guiding element (20), which deflects the end (4) of the at least one bowden cable (1) to the side under a movement in the direction of the receptacle (32a, 32b) through the at least one opening (11) of the support (10) to engage the receptacle (32a, 32b); characterized in that d. the guiding element (20) is stationary arranged at the support (10) between the at least one opening (11) of the support (10) and the at least one receptacle (32a, 32b). Connecting unit according to claim 1 where the at least one receptacle (32a, 32b) comprises a slit on the side (33a, 33b) for the engagement of the end (4) of the at least one bowden cable (1) with the receptacle (32a, 32b). Connecting unit according to claim 1 or claim 2 where the guiding element (20) comprises a groove-like guiding surface (23) for a deflection to the side of the end (4) of the at least one bowden cable (1). Connecting unit according to claim 3 wherein the groove-like guiding surface (23) of the guiding element (20) comprises a slit-like recess (24) through which the at least one bowden cable (1) extends after the end (4) has engaged the at least one receptacle (32a, 32b) of the pulling element (30). Connecting unit according to one of the preceding claims where the pulling element (30) comprises a second receptacle (32b) and where essentially parallel to the first bowden cable (1) a second bowden cable (2) extends through a second opening (12) in the support (10) and where the guiding element (20) deflects an end (5) of the second bowden cable (2) to the side under a movement in the direction of the second receptacle (32b) of the pulling element (30) for an engagement with the second receptacle (32b) of the pulling element (30). Connecting unit according to claim 5 where the guiding element (20) comprises a second groove-like guiding surface (21) for deflecting the end (5) of the second bowden cable (2) and a second slit-like recess (22) of the second groove-like guiding surface (21) through which the second bowden cable (2) extends, after the end (5) of the second bowden cable (2) has engaged the second receptacle (32b) of the pulling element (30). Connecting unit according to claim 6 where the two groove-like guiding surfaces (21, 23) are arranged on opposite sides of the guiding element (20). Connecting unit according to claim 7 where the pulling element is provided as an equalizer (30) and the two bowden cables (1, 2) are braking cables for a parking brake of a vehicle. Connecting unit according to claim 8 where the equalizer (30) contacts the front side of the guiding element (20) when the parking brake is disengaged. Connecting unit according to claim 9 where the two receptacles (32a, 32b) for the two braking cables are provided as essentially hemispherical recesses in the equalizer (30) arranged in circular recesses (26) of the front side of the guiding element (20) when the brake is disengaged. Parking brake in a vehicle comprising for the transmission of the movement of the braking lever to at least one braking cable a connecting unit according to one of the claims 8 to 10. Method for establishing a connection between at least one bowden cable (1) and a movably arranged pulling element (30) for the transmission of pulling movements from the pulling element (30) to the at least one bowden cable (1) where the method comprises the following steps: a. moving of the end (4) of the at least one bowden cable (1) to be connected in the direction of a receptacle (32a) in the pulling element (30); b. deflection to the side of the end (4) of the bowden cable (1) from the direction of movement by a guiding element (20) which is stationary arranged thereby elastically bending the bowden cable (1); c. elastical spring-back of the end (5) of the at least one bowden cable (1) into the receptacle (32a). Method according to claim 12 where the receptacle (32a) is hemispherically shaped and where the method comprises after step c further the step of backwards pulling the end (4) of the cable (1) for a secure arrangement of the end (4) in the hemispherical receptacle (32a).

Inventors: GABAS CARLOS, GABAS, CARLOS
Applicants: FICO CABLES SA, FICO CABLES, S.A.
Application year: 1999
Main classification: F16C1
IPC codes: B60T11, F16C1