Interchangeable Firearm Choke With Sealing Ring

Solution Overview

Problem

Interchangeable chokes for smooth-bore firearms tend to unscrew during firing and can jam in the barrel due to powder and lead residue accumulation, requiring specialized maintenance to disassemble without damage.

Innovation Solution

An interchangeable choke with a flexible or heat-shrinkable sealing ring housed in a beveled constriction on the outer surface, providing a mechanical seal that prevents residue deposition and facilitates easy assembly and disassembly, using a combination of mechanical coupling and sealing means to secure the choke in place.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If interchangeable choke is used with fine screw thread for mounting, then ease of assembly and adaptability is improved, but reliability deteriorates due to unscrewing during firing and jamming from residue accumulation

Engineering Contradiction:

Core Design Contradiction:

Adaptability or versatilityVSReliability

Solution Approach 1:

The sealing function is segmented from the main choke body and implemented as a separate sealing ring component. This sealing ring can be independently replaced and maintained, allowing the choke to be divided into functional segments that can be serviced separately without replacing the entire assembly.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The sealing ring is pre-installed in the constriction of the choke's external surface before mounting. This preliminary sealing action prevents residue accumulation from the start, eliminating the progressive jamming problem that occurs with conventional chokes.

Inventive Principle:

Principle #10Preliminary action

2Ease of operation

If functional clearance is provided between choke external diameter and barrel housing, then ease of operation is improved, but object-generated harmful factors worsen due to powder and lead residue deposition

Engineering Contradiction:

Core Design Contradiction:

Ease of operationVSObject-generated harmful factors

Solution Approach 1:

The sealing ring acts as an intermediary element between the choke and barrel housing. It fills the functional clearance space with a sealing material that prevents residue deposition while maintaining the necessary clearance for assembly and disassembly operations.

Inventive Principle:

Principle #24Intermediary (Mediator)

Solution Approach 2:

A flexible sealing ring is used to create the seal in the constriction of the choke. The flexibility of the sealing ring allows it to conform to the surfaces it seals against while maintaining contact pressure to prevent residue accumulation in the clearance space.

Inventive Principle:

Principle #30Flexible shells and thin films

3Reliability

If sealing means are added to prevent residue deposition, then reliability is improved, but device complexity increases

Engineering Contradiction:

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The sealing ring is designed as a simple, inexpensive component that can be easily replaced when worn. This approach trades the complexity of a maintenance-free seal for a simple replaceable component, reducing overall system complexity while maintaining reliability.

Inventive Principle:

Principle #27Cheap short-living objects (Disposable)

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

Prevents the choke from unscrewing during firing and allows for easy maintenance by preventing residue accumulation, ensuring the choke can be disassembled without issue and reducing the need for specialized gunsmith intervention.

Implementation Method 1

a sealing ring made of a flexible material such as, for example, rubber, elastomer or heat-shrinkable material

Methodology Applied

Scientific EffectElasticity: Elasticity

Implementation Method 2

sealing ring made of a flexible material such as, for example, rubber, elastomer or heat-shrinkable material

Methodology Applied

Scientific EffectThermal contraction: Thermal Contraction

Implementation Method 3

The frictional forces, which result from contact with the compressed sealing ring, will ultimately generate a torque of forces which opposes the torque of forces required for the dismantling of the choke

Methodology Applied

Scientific EffectFriction: Friction

Data Source

PatentEP2159530B1Interchangeable choke for a smooth bore firearm

Publication Date: 2015.03.11

Figure 1~2
Figure 3~4

AI summary

Interchangeable choke (3) for a smoothbore firearm (2), this choke (3) being provided with mechanical coupling means (8) for mounting and dismounting the choke (3), characterized in that the choke (3) is provided with additional sealing means (16) in order to give the choke (3), at least in one place, a seal with respect to the barrel (2), as well as to prevent the unscrewing of the choke (3) during firing.