Firearm Housing Bushing with Adjustable Slot for Barrel Root

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing firearm housings with interchangeable barrels face challenges in achieving a secure and precise fit while allowing for easy barrel changes, often requiring high manufacturing accuracy and leading to undesirable stresses due to inadequate play between the barrel root and housing socket.

Innovation Solution

A housing design featuring a combined actuating element for both clamping and spreading devices, allowing the slot to be widened for easier barrel insertion and securely anchored in a narrowed position, reducing manufacturing accuracy requirements and distributing anchoring force effectively.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Manufacturing precision

If the clearance between the barrel root and receiver bushing is reduced to improve attachment precision, then the manufacturing precision requirements increase, but the ease of manufacture decreases

Engineering Contradiction:
Improveattachment precisionVSAvoidease of manufacture
Core Design Contradiction:
Manufacturing precisionVSEase of manufacture

Solution Approach 1:

The invention divides the bushing into two functional parts: a press-fit section that provides precise attachment of the barrel root, and a clamping section with a slot that allows for adjustment and clamping. This segmentation allows each part to be optimized independently - the press-fit section for precision and the clamping section for ease of manufacture and assembly.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The invention introduces a dynamic clamping mechanism with a movable clamping element that can adjust the slot width. This allows the bushing to transition from a static press-fit structure to a dynamic clamped structure, enabling precise attachment while maintaining ease of manufacture through adjustable clearance.

Inventive Principle:
Principle #15Dynamics

2Ease of manufacture

If the clearance between the barrel root and receiver bushing is increased to ease manufacture, then the ease of manufacture improves, but the attachment precision deteriorates

Engineering Contradiction:
Improveease of manufactureVSAvoidattachment precision
Core Design Contradiction:
Ease of manufactureVSManufacturing precision

Solution Approach 1:

The bushing is segmented into a press-fit section for precise barrel root attachment and a clamping section with adjustable slot. This allows the clamping section to have larger clearance for ease of manufacture while the press-fit section maintains high precision.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The invention changes the parameter of slot width dynamically through the clamping mechanism. The slot can be widened during assembly to facilitate barrel insertion, then narrowed during clamping to secure the barrel, thus accommodating both ease of manufacture and attachment precision requirements.

Inventive Principle:
Principle #35Parameter changes

3Ease of operation

If the clamping mechanism deforms the bushing more to compensate for excessive clearance, then the ease of operation improves, but the stress on the receiver and clamping mechanism increases

Engineering Contradiction:
Improveease of operationVSAvoidstress on receiver
Core Design Contradiction:
Ease of operationVSStress or pressure

Solution Approach 1:

The invention introduces a dynamic slot width adjustment mechanism that allows the bushing to adapt its geometry during operation. The slot can be widened to facilitate easy barrel insertion, then narrowed during clamping to secure the barrel without excessive deformation, thus reducing stress on the receiver.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The slot width parameter is changed dynamically through the clamping mechanism. By adjusting the slot width before and during clamping, the system achieves easy operation for barrel changes while controlling the deformation level to minimize stress on the receiver structure.

Inventive Principle:
Principle #35Parameter changes

4Manufacturing precision

If separate clamping screws and spreading devices are used to achieve precise barrel attachment, then the attachment precision improves, but the device complexity increases

Engineering Contradiction:
Improveattachment precisionVSAvoiddevice complexity
Core Design Contradiction:
Manufacturing precisionVSDevice complexity

Solution Approach 1:

The invention merges the clamping function and spreading function into a single integrated clamping mechanism. The clamping element simultaneously performs both functions by adjusting the slot width, eliminating the need for separate clamping screws and spreading devices, thus reducing device complexity while maintaining attachment precision.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The clamping mechanism is designed as a multi-functional element that can both widen the slot for spreading and narrow it for clamping. This universal mechanism replaces multiple separate components, achieving precise barrel attachment with a single integrated device that performs multiple functions.

Inventive Principle:
Principle #6Universality (Multi-functionality)

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

Ensures a high-precision and secure barrel anchoring with reduced manufacturing complexity and stress on the tensioning device, facilitating easy operation and space-saving design.

Implementation Method 1

the spreading device significantly facilitates the axial insertion of the barrel root of the reversible barrel into the bushing by widening the slot and thus spreading the bushing

Methodology Applied
Scientific EffectElastic deformation: Elasticity

Implementation Method 2

In the narrowed slot position, the barrel root, and therefore the reversible barrel, is particularly securely anchored to the housing

Methodology Applied
Scientific EffectFriction: Friction

Implementation Method 3

the barrel root is already press-fitted in the bushing in the slot's initial position, unaffected by the clamping device, a highly precise fit of the barrel root in the bushing is ensured

Methodology Applied
Scientific EffectInterference fit: Mechanical Force

Data Source

PatentEP3619494B1Housing for a firearm with an exchangeable barrel
Publication Date: 2021.05.19 STEYR ARMS GMBH
  • EP3619494B1 patent drawingFigure 1~2

AI summary

The invention relates to a housing (1) for a firearm with an exchangeable barrel, comprising a bushing (2) in which the barrel root (3) of the exchangeable barrel can be inserted in the axial direction. The bushing (2) has a slot (7) in the axial direction and a clamping device (8) for adjusting the slot (7) from a starting position into a narrowed position, and the bushing (2) is designed to receive the barrel root (3) in a press-fitting manner when the slot (7) is in the starting position, which is uninfluenced by the clamping device (8), and has a spreading device (17) for moving the slot (7) from the starting position into an expanded position.