Removable Sliding Nut Plate with Front Side Slot Cover
Publication Date: 2015-Dec-01
The IP.com Prior Art Database
A Nut plate allows the installation of a component where there is a lack of wrench access and saves time during installation The fixed nut plate and floating nut plate are two configurations which is commonly used in aerospace and automobile industry The limitation of these nut plates is that they provide very little or no tolerance variation between two connecting parts This paper proposes a novel cost effective and lightweight removable sliding nut plate design to provide wide tolerance variation between two connecting parts The proposed design provides an integrated washer for the front side of the slot to provide support back over the slot and helps to uniformly distribute the loads
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Removable Sliding Nut-Plate with Front Side Slot Cover
Shawn Alstad ABSTRACT
A Nut-plate allows the installation of a component where there is a lack of wrench access and saves time during installation. The fixed nut-plate and floating nut-plate are two configurations which is commonly used in aerospace and automobile industry. The limitation of these nut-plates is that they provide very little or no tolerance variation between two connecting parts. This paper proposes a novel, cost effective and lightweight removable sliding nut-plate design to provide wide tolerance variation between two connecting parts. The proposed design provides an integrated washer for the front side of the slot to provide support back over the slot and helps to uniformly distribute the loads.
Nut-Plates are extensively used in number of applications to provide a threaded insert for a bolt or screw. In the nut-plate assembly, bolt and nut (fixed with plate) is coupled between the fixed part and removable part and tightened down. This permits the user to install the bolt without using the wrench on the nut side. This saves time during installation or removal of the part, reduces the assembly part counts and blind installation of the part is possible when there is little space available or no access to tighten the nut.
There are different types of nut-plate configurations available. The most common is a simple insert with a pad, which is usually riveted to the work piece. The other one provides the radial float, known as a floating nut-plate. The floating nut plate allows the nut to move slightly to enlarge the positioning tolerance of the mounted part. These floating nut-plates were designed for aerospace industry as it increases the positioning
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tolerance of the mounted part. Recently these are also commonly used in automotive and other industries.
Despite a number of advantages of the nut-plate design, there are few limitations associated with above nut-plate designs. In the riveted nut-plate type assembly, it is difficult to replace the nut-plate assembly in case of any damage or during nut strip off condition. The other limitation with this type of design is that it is impossible to provide wide tolerance variations to the mounted part as it is fixed with nut-plate hole through bolt. This could be resolved by providing a slot at the parent part (over which mounted part is attached) or at the nut-plate. A typical arrangement for the slot, wherein one part has the slot and the other has the hole.
However, slots in the nut-plate are not common in aerospace industry, despite having an advantage over the hole. This is because the slot poses two problems. First on the mechanical strength, the parent part is essentially weaker with the slot than with a hole. Second, a washer is required to bridge over the slot. This helps the component that touch the slot face, to rest against the washer face. This provides material back over the...