Motion-transmitting remote control cable assemblies, such as “push-pull cables,” are used for transmitting force or load and/or motion, typically along a curved path e.g. in aircraft, automotive, and marine environments, etc. Known cable assemblies can be used for transmitting load and motion in both push and pull type applications. In the automotive environment, typical applications include, but are not limited to, accelerators, or similar applications.
A motion-transmitting remote control cable assembly for transmitting motion along a curved path typically includes a flexible core element (core or strand) slidably enclosed within a flexible outer sheath (conduit) with a conduit fitting attached to each end. Each conduit fitting attaches to a corresponding bracket or other mounting fixture, support structure or the like. The cable assembly further includes, typically, a terminal sub-assembly at each end. A first terminal sub-assembly is secured (or adapted to be secured) to a controlled member, e.g., a movable lever, etc. of a motor vehicle transmission. The terminal sub-assembly at the other end is secured (or adapted to be secured) to an actuator, i.e. a control member such as a handle, motor output member, etc. Typically, the actuator member and the controlled member each provides a mounting pin or other suitable feature at a mounting point for suitable connection to the corresponding terminal sub-assembly, such that the cable assembly is able to transfer load or motion between the two mounting points. That is, moving the actuator member transmits force/motion via longitudinal movement of the strand within the sheath, to correspondingly move the controlled member. (It should be understood that in some applications the control member and the controlled member may from time to time reverse roles or may otherwise share the control and controlled roles.)
The strand of a motion-transmitting cable assembly is often secured to a mounting pin or other attachment component at the aforesaid mounting point of the controlled or control member by a terminal or core-adjuster assembly. Mounting pins and other such attachment components can have a relatively large dimensional tolerance range due to manufacturing variations and the like. Large dimensional tolerance ranges are seen, for example, in the attachment pins of automobile transmission shift systems. As a result of this large tolerance range, there can be a difference in fit from one unit to the next, between the terminal or core-adjuster assembly and the mounting pin, which in some units results in a gap and the possibility of relative movement between the fitting and the pin referred to as lash. In certain cases lash causes inaccuracy in the transmission shift system throughout its full range of movement. Additionally, these known terminal assemblies often have large installation loads (the forces required to attach the terminal sub-assembly to the pin or other mounting component) in order to obtain correspondingly high extraction loads (the forces required to inadvertently remove the terminal sub-assembly from the pin or other mounting component). Traditionally, the problem of lash is mitigated by the use of an isolator at the interconnection between the pin and the terminal sub-assembly, designed to absorb vibration. The problem with traditional isolators is that by their very nature they must be made of a softer material that has significant give or resiliency to absorb the vibration and as a result suffer from increased wear and breakdown in areas were the force or load is concentrated, i.e. where the pin contacts the isolator. Another problem with traditional terminal assemblies is determining correct orientation during assembly and installation. Having a number of interconnecting part to be assembled and installed on an assembly line can provide a potential for improperly assembled or installed parts that could lead to future failure of the device.
Accordingly, there is a need in the art for improved motion transmitting remote control cable assemblies and for end fittings for motion transmitting remote control cable assemblies, which account for dimensional tolerance ranges of mating components and are operative to reduce vibration during operation. There is also a need for motion transmitting remote control cable assemblies and end fitting for such cable assemblies, which require relatively low installation loads while maintaining relatively high extraction loads. There is also a need for motion transmitting remote control cable assemblies and end fittings for same, resistant to wear or breakdown at the area of the interconnection between the terminal sub-assembly and a mounting pin. There is also a need for terminal assemblies that are simple to assemble and install with proper orientation.
It is an object of the present invention, to provide cable assemblies addressing some or all of the above problems. It is another object to provide end fittings for motion transmitting cable assemblies, addressing some or all of the above problems.