# US 11,078,704 B2 · Method and apparatus for adjusting the closing force of a door

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 11,078,704 B2
- Document ID: US11078704B2
- Status: Granted
- Kind: B2
- Application number: 16/279,663
- Filed: 2019-02-19
- Published: 2019-10-17
- Granted: 2021-08-03
- Earliest claimed: 2016-05-16
- Assignees: Schlage Lock Company LLC
- Applicants: Schlage Lock Company LLC
- Inventors: Nicholas Long; Aaron P. McKibben; Jason Fodstad
- Web page: https://patentgrep.com/patent/US11078704B2

## CPC

- E05F 1/105: {with a compression spring}
- E05F 15/70: with automatic actuation
- G01L 3/242: {by measuring and simultaneously multiplying torque and velocity}
- E05F 15/63: operated by swinging arms
- E05F: DEVICES FOR MOVING WINGS INTO OPEN OR CLOSED POSITION; CHECKS FOR WINGS; WING FITTINGS NOT OTHERWISE PROVIDED FOR, CONCERNED WITH THE FUNCTIONING OF THE WING
- G01L: MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE (weighing G01G)

## Abstract

A method of adjusting the closing force of a door coupled to a door closer assembly having a bias element. The method includes determining the kinetic energy of the door without using the weight or other dimensions of the door. The determined kinetic energy is used to adjust the closing force of an electro-mechanical door closer that includes a spring and a motor. The door includes the use of one, some of, or all of an accelerometer, an angular position sensor, a time to close, a breaking torque, and a controller to identify values a acceleration, velocity, and/or position of the door. The identified values are provided to the controller, which is configured to calculate the kinetic energy of the door. The calculated kinetic energy is used to determine the closing velocity of the door closure to ensure proper operation of the door at the point of installation.

## Claims

### Claim 1

A method of operating a door closer coupled to a door, the method comprising:
initiating movement of the door from a first position toward a second position by exerting a net torque on the door, the net torque having a first net torque value when the door is in the first position, and a second net torque value when the door is in the second position;
measuring movement of the door from the first position to the second position;
determining a net torque change between the first net torque value and the second net torque value;
determining a mass moment of inertia of the door based on the measured movement of the door and the net torque change;
determining the kinetic energy of the door based on the mass moment of inertia; and
modifying operation of the door closer based on the kinetic energy of the door to adjust a movement speed of the door.

### Claim 2 (depends on 1)

The method of claim 1, further comprising exerting, by a spring of the door closer, a closing torque on the door; and
wherein the net torque includes the closing torque.

### Claim 3 (depends on 2)

The method of claim 2, further comprising exerting, by a motor of the door closer, a braking torque on the door; and
wherein the net torque includes the braking torque.

### Claim 4 (depends on 3)

The method of claim 3, wherein the braking torque opposes the closing torque.

### Claim 5 (depends on 3)

The method of claim 3, further comprising varying the braking torque.

### Claim 6 (depends on 3)

The method of claim 3, further comprising maintaining the braking torque at a constant braking torque value.

### Claim 7 (depends on 1)

The method of claim 1, wherein the measuring movement of the door comprises determining, with an accelerometer, an acceleration of the door during the movement of the door from the first position to the second position; and
wherein the determining the mass moment of inertia of the door based on the measured movement of the door and the net torque change comprises determining the mass moment of inertia based on the measured acceleration and the net torque change.

### Claim 8 (depends on 1)

The method of claim 1, wherein the measuring movement of the door comprises measuring, by an accelerometer of the door closer, an acceleration of the door; and
wherein the method further comprises integrating the acceleration of the door to determine an angular velocity of the door.

### Claim 9 (depends on 8)

The method of claim 8, wherein the determining the net torque change comprises determining the net torque change based on the angular velocity of the door.

### Claim 10 (depends on 8)

The method of claim 8, further comprising integrating the angular velocity of the door to determine an angular position of the door; and
wherein the determining the net torque change comprises determining the net torque change based on the angular position of the door.

### Claim 11 (depends on 1)

The method of claim 1, further comprising determining the first net torque value and the second net torque value.

### Claim 12 (depends on 11)

The method of claim 11, wherein the determining the first net torque value comprises determining the first net torque value based on an angular position of the door; and
wherein the determining the second net torque value comprises determining the second net torque value based on information stored in a memory of the door closer.

### Claim 13 (depends on 1)

The method of claim 1, wherein the door closer comprises a motor operable to exert a motor torque on the door; and
wherein the modifying operation of the door closer comprises adjusting the motor torque.

### Claim 14

A method of operating a door closer coupled to a door, the method comprising:
with the door in a first position, exerting a net torque on the door to move the door from the first position to a second position;
varying the net torque from a first net torque value when the door is in the first position to a second net torque value when the door is in the second position, thereby resulting in a net torque change;
monitoring, by an accelerometer of the door closer, acceleration of the door as the door moves from the first position to the second position;
determining a mass moment of inertia of the door based on the acceleration of the door and the net torque change;
determining the kinetic energy of the door based on the mass moment of inertia; and
modifying operation of the door closer based on the kinetic energy of the door to adjust a movement speed of the door.

### Claim 15 (depends on 14)

The method of claim 14, further comprising determining the net torque change based on at least one measured parameter.

### Claim 16 (depends on 15)

The method of claim 15, wherein the at least one measured parameter comprises the acceleration of the door.

### Claim 17 (depends on 15)

The method of claim 15, wherein the at least one measured parameter includes a first measured parameter related to the first net torque value and a second measured parameter related to the second net torque value.

### Claim 18 (depends on 14)

The method of claim 14, wherein exerting the net torque comprises:
exerting, by a spring of the door closer, a first torque urging the door from the first position toward the second position; and
exerting, by a motor of the door closer, a second torque resisting movement of the door from the first position toward the second position.

### Claim 19 (depends on 14)

The method of claim 14, wherein the door closer comprises a motor operable to exert a motor torque on the door; and
wherein the modifying operation of the door closer comprises adjusting the motor torque.

### Claim 20 (depends on 14)

The method of claim 14, wherein the door closer comprises a spring exerting a variable torque on the door; and
wherein the method further comprises:
determining a first door closer position when the door is in the first position;
determining the first net torque value based on the first door closer position and a known relationship between values of the variable torque and positions of the door closer;
determining a second door closer position when the door is in the second position; and
determining the second net torque value based on the second door closer position and the known relationship.