Low Profile Door Closer Using Strap and Spring

Solution Overview

Problem

Conventional door closers, such as helical tension springs, pneumatic tubes, and hydraulic mechanisms, face issues like user pinching, exposure to elements, aesthetics, high profile, and cost, as well as unsightly appearance and abrasion.

Innovation Solution

A door closer design featuring a housing with a helical extension spring, a strap, a strap guide, and a spring anchor, which provides a compact, aesthetically pleasing, and cost-effective solution by using a strap to engage with the door and frame, minimizing exposure and wear.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a helical tension spring is used as a door closer, then the door closing function is achieved, but the spring may pinch users and become exposed to elements causing dirt and corrosion

Engineering Contradiction:

Improvedoor closing functionVSAvoiduser pinching and exposure to elements

Core Design Contradiction:

ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The spring is nested inside a housing that is attached to the door frame. The housing encloses the spring, preventing user contact and protecting it from environmental elements. The strap mechanism extends from the housing to connect to the door, allowing the spring to remain hidden while still performing its closing function.

Inventive Principle:

Principle #7Nested doll (Nesting)

Solution Approach 2:

A strap is introduced as an intermediary component between the spring and the door. The strap transmits the closing force from the spring to the door without requiring direct exposure of the spring. This mediator allows the spring to remain protected while still achieving the door closing function.

Inventive Principle:

Principle #24Intermediary (Mediator)

2Device complexity

If a bare spring is used, then the door closer is simple and cost-effective, but the spring is unsightly and may abrade the door edge

Engineering Contradiction:

Improvedoor closer structureVSAvoidaesthetic issues and door edge abrasion

Core Design Contradiction:

Device complexityVSObject-generated harmful factors

Solution Approach 1:

The spring is nested inside a housing that is attached to the door frame. The housing encloses the spring, preventing user contact and protecting it from environmental elements. The strap mechanism extends from the housing to connect to the door, allowing the spring to remain hidden while still performing its closing function.

Inventive Principle:

Principle #7Nested doll (Nesting)

Solution Approach 2:

A strap is introduced as an intermediary component between the spring and the door. The strap transmits the closing force from the spring to the door without requiring direct exposure of the spring. This mediator allows the spring to remain protected while still achieving the door closing function.

Inventive Principle:

Principle #24Intermediary (Mediator)

3Reliability

If a pneumatic tube or hydraulic mechanism is used, then the door closing function is improved, but the device has a high profile and projects into adjacent living space

Engineering Contradiction:

Improvedoor closing functionVSAvoidprofile height

Core Design Contradiction:

ReliabilityVSLength of moving object

Solution Approach 1:

The patent extracts the essential closing function from complex pneumatic or hydraulic systems and implements it using a simple spring mechanism. By removing unnecessary components and using only the essential spring-strap configuration, the solution achieves reliable door closing with a minimal profile that does not project into living space.

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

The patent uses a thin strap instead of bulky mechanical linkages. The flexible strap allows the spring to be positioned close to the door frame while still effectively closing the door, minimizing the profile height and avoiding projection into adjacent living space.

Inventive Principle:

Principle #30Flexible shells and thin films

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

The solution effectively closes doors without pinching users, reduces exposure to elements, and maintains aesthetics while being cost-effective and minimizing wear on the door edges.

Implementation Method 1

A door closer typically includes an energy storage device configured to store energy imparted to the door when it is opened and to use the stored energy to close the door when it is released.

Methodology Applied

Scientific EffectElastic potential energy storage: Spring

Implementation Method 2

A door closer may be embodied as nothing more than a helical tension spring connected between the door and a mating door frame.

Methodology Applied

Scientific EffectHelical spring mechanism: Spring

Data Source

PatentUS10577846B2Low profile door closer

Publication Date: 2020.03.03 LIPPERT COMPONENTS INC

AI summary

A door closer includes a helical extension spring disposed within a housing. A first end of the spring is attached to a spring anchor attached to a first end of the housing. A second end of the spring is attached to a first end of a strap. The strap passes through a strap guide attached to a second end of the housing. A second end of the strap is configured for attachment to a door jamb. The spring anchor and strap guide are configured for attachment to a door.