Load sensor configurations for caster assemblies of a patient support apparatus

Patent metadata

Field	Value
Publication number	US-11123247-B2
Application number	US-201816046150-A
Country	US
Kind code	B2
Filing date	Jul 26, 2018
Priority date	Jul 27, 2017
Publication date	Sep 21, 2021
Grant date	Sep 21, 2021

Abstract

A patient support apparatus comprises a base supported by caster assemblies with each caster assembly comprising a stem, a caster wheel, and a caster wheel axle. A patient support surface is coupled to the base and is configured to receive a load. One or more load sensors are integrated with at least one of the stem, the caster wheel, or the caster wheel axle for measuring the load. One or more of the caster assemblies can be coupled to a steering motor, which controls orientation of the caster assembly. A controller can control the steering motors based on analyzing the measurements of the load sensor. The load sensors can produce measurements indicative of both vertical load and non-vertical load applied to the caster assembly. The controller can also analyze the measurements of the load sensor to determine the load received by the patient support surface by negating the non-vertical load.

First claim

The invention claimed is:

1. A patient support apparatus comprising:
a base supported by caster assemblies with each caster assembly comprising a stem, a caster wheel, and a caster wheel axle, wherein one or more of the caster assemblies is coupled to a steering motor configured to control orientation of one or more of the caster assemblies;
a patient support surface coupled to the base and configured to receive a substantially vertically applied load;
a load sensor cooperative with at least one of the stem, the caster wheel, or the caster wheel axle to measure the load; and
a controller configured to:
control the steering motor of one or more of the caster assemblies based on analyzing measurements of the load sensor,
determine an orientation of one or more of the caster assemblies based on the measurements of the load sensor in a substantially vertical direction, and
control the steering motor of one or more of the caster assemblies based on the determined orientation.

2. The patient support apparatus of claim 1 , wherein the load sensor is coupled to the stem and configured to measure load applied to the stem.

3. The patient support apparatus of claim 2 , wherein the load sensor is a load cell disposed around the stem.

4. The patient support apparatus of claim 2 , wherein the load sensor is disposed on a distal end of the stem.

5. The patient support apparatus of claim 4 , wherein the load sensor is a load cell configured to measure compressional force applied to the distal end of the stem.

6. The patient support apparatus of claim 4 , wherein the load sensor is a displacement sensor configured to undergo displacement in response to the load applied to the distal end of the stem and to measure the displacement.

7. The patient support apparatus of claim 1 , wherein the load sensor is coupled to the caster wheel axle and configured to measure load applied to the caster wheel axle.

8. The patient support apparatus of claim 1 , wherein the caster wheel comprises pressurized air and wherein the load sensor comprises a pressure sensor configured to measure air pressure of the caster wheel.

9. The patient support apparatus of claim 1 , wherein the load sensor is configured to produce measurements indicative of vertical load and non-vertical load applied to each caster assembly.

10. The patient support apparatus of claim 9 , wherein the controller is configured to analyze the measurements of the load sensor to determine the load received by the patient support surface by negating the non-vertical load.

11. The patient support apparatus of claim 1 , wherein the controller is configured to control the steering motor of the one or more of the caster assemblies to move the one or more of the caster assemblies to a trailing orientation with respect to a direction of desired movement.

12. The patient support apparatus of claim 1 , wherein the steering motor is coupled to the stem.

13. The patient support apparatus of claim 1 , wherein the load sensor is at least one of a load cell, a strain gauge, a pressure sensor, a displacement sensor, a compression sensor, or a weight sensor.

14. A patient support apparatus comprising:
a base supported by caster assemblies with one or more of the caster assemblies being coupled to a steering motor configured to control orientation of the one or more of the caster assemblies;
a patient support surface coupled to the base and configured to receive a substantially vertically applied load;
a load sensor integrated into the one or more of the caster assemblies and with the load sensor configured to produce measurements indicative of the load; and
a controller configured to:
control the steering motor of the one or more of the caster assemblies based on analyzing the measurements of the load sensor
determine an orientation of the one or more of the caster assemblies based on analyzing the measurements of the load sensor in a substantially vertical direction, and
control the steering motor of the one or more of the caster assemblies based on the determined orientation.

15. The patient support apparatus of claim 14 , wherein the controller is configured to control the steering motor of the one or more of the caster assemblies to move the one or more of the caster assemblies to a trailing orientation with respect to a direction of desired movement.

16. The patient support apparatus of claim 14 , wherein the one or more of the caster assemblies comprises a stem, wherein the steering motor is coupled to the stem, and wherein the load sensor is a load cell.

Assignees

• Stryker Corp

Inventors

• Nahavandi Kurosh

Classifications

• A61G7/0527 Primary

  Weighing devices · CPC title

• A61G2203/32

  for force · CPC title

• A61G2203/44

  for weight · CPC title

• G01L1/2237

  the direction being perpendicular to the central axis · CPC title

• G01L17/00

  Devices or apparatus for measuring tyre pressure or the pressure in other inflated bodies · CPC title