Weight scale for a patient lift system, a control system for the weight scale, and a method for weighing a patient supported on the weight scale

Patent metadata

Field	Value
Publication number	US-8987616-B2
Application number	US-201213488963-A
Country	US
Kind code	B2
Filing date	Jun 5, 2012
Priority date	Jun 5, 2012
Publication date	Mar 24, 2015
Grant date	Mar 24, 2015

Abstract

A weight scale for a patient lift system includes a frame assembly. A plurality of force sensors are coupled to the frame assembly. Each of the plurality of force sensors is configured to generate a signal indicative of a measured weight force. A foot rest panel is coupled to the frame assembly. The foot rest panel is configured to support a patient. An angle sensor is operatively coupled to the frame assembly. The angle sensor is configured to generate a signal indicative of an angle of the frame assembly with respect to a horizontal reference plane. A controller is coupled in signal communication with each force sensor and the angle sensor. The controller includes one or more processors configured to receive signals from each force sensor and the angle sensor to determine an actual weight force of the patient.

First claim

What is claimed is:

1. A weight scale for a patient lift system, the weight scale comprising:
a frame assembly;
a plurality of force sensors coupled to the frame assembly, each force sensor of the plurality of force sensors configured to generate a signal indicative of a measured weight force;
a base frame of the frame assembly comprising a first leg having a first end and an opposing second end, the first leg defining a first channel between the first end and the second end and a second leg having a first end and an opposing second end, the second leg defining a second channel between the first end and the second end of the second leg;
a first castor support link positioned within the first channel, the first castor support link having a first end defining a first slot and an opposing second end defining a second slot;
a first force sensor of the plurality of force sensors positioned within the first slot and coupled to the first leg at the first leg first end;
a second force sensor of the plurality of force sensors positioned within the second slot and coupled to the first leg at the first leg second end;
a second castor support link positioned within the second channel, the second castor support link having a first end defining a third slot and an opposing second end defining a fourth slot;
a third force sensor of the plurality of force sensors positioned within the third slot and coupled to the second leg at the second leg first end;
a fourth force sensor of the plurality of force sensors positioned within the fourth slot and coupled to the second leg at the second leg second end;
a foot rest panel coupled to the frame assembly, the foot rest panel configured to support a patient;
an angle sensor operatively coupled to the frame assembly, the angle sensor configured to generate a signal indicative of an angle of the frame assembly with respect to a horizontal reference plane; and
a controller coupled in signal communication with each force sensor and the angle sensor, the controller comprising one or more processers configured to receive signals from each force sensor and the angle sensor to determine an actual weight force of the patient.

2. The weight scale of claim 1 , wherein the first force sensor comprises:
a load cell, the load cell comprising a pin; and
a castor support coupled to the first leg first end and the castor support link first end, the castor support defining a bore configured to receive the pin with the castor support coupled to the first leg.

3. The weight scale of claim 2 , further comprising a castor coupled to the castor support.

4. The weight scale of claim 1 , wherein each force sensor is configured to output force vector information including the measured weight force to the controller indicative of a portion of the actual weight force of the patient measured by each force sensor.

5. The weight scale of claim 4 , wherein the controller is configured to generate weight information including the actual weight force based at least in part on force vector information received from each force sensor.

6. The weight scale of claim 5 , wherein the controller is configured to compensate for the force vector information received from each force sensor based on an angle information output received from the angle sensor to generate the actual weight force.

7. The weight scale of claim 1 , further comprising a patient input device in signal communication with the controller, the patient input device comprising a display configured to display information received from the controller.

8. The weight scale of claim 1 , wherein the controller is configured to calibrate the plurality of force sensors.

9. The weight scale of claim 1 , wherein the controller is configured to calibrate the angle sensor.

10. The weight scale of claim 1 , wherein each force sensor comprises a load cell and a castor support operatively coupled to the load cell.

11. The weight scale of claim 1 , wherein the angle sensor comprises an accelerometer.

12. A control system for a patient lift system comprising a frame assembly, a foot rest panel coupled to the frame assembly, the foot rest panel configured to support a patient, and a weight scale comprising a plurality of force sensors coupled to the frame assembly and an angle sensor operatively coupled to the frame assembly, the control system comprising:
a controller coupled in signal communication with each force sensor of a plurality of force sensors and the angle sensor, the controller comprising one or more processers configured to receive signals from each force sensor and the angle sensor to determine an actual weight force of the patient and output weight information including the actual weight force to a display;
a base frame of the frame assembly comprising a first leg having a first end and an opposing second end, the first leg defining a first channel between the first end and the second end and a second leg having a first end and an opposing second end, the second leg defining a second channel between the first end and the second end of the second leg;
a first castor support link positioned within the first channel, the first castor support link having a first end defining a first slot and an opposing second end defining a second slot;
a first force sensor of the plurality of force sensors positioned within the first slot and coupled to the first leg at the first leg first end;
a second force sensor of the plurality of force sensors positioned within the second slot and coupled to the first leg at the first leg second end;
a second castor support link positioned within the second channel, the second castor support link having a first end defining a third slot and an opposing second end defining a fourth slot;
a third force sensor of the plurality of force sensors positioned within the third slot and coupled to the second leg at the second leg first end; and
a fourth force sensor of the plurality of force sensors positioned within the fourth slot and coupled to the second leg at the second leg second end.

13. The control system of claim 12 , wherein the one or more processors are further configured to receive force vector data from each force sensor and calibrate the weight scale based on the received force vector data, wherein the force vector data includes an individual weighing factor attributed to a weight distribution of the patient lift system.

14. The control system of claim 12 , wherein the one or more processors are configured to apply a Gauss-Jordan elimination method to calibrate the weight scale.

15. The control system of claim 12 , wherein the one or more processors are configured to determine a foot rest panel mounting offset.

16. The control system of claim 12 , wherein the one or more processors are configured to determine a weight of the patient lift system and the actual weight force of the patient based on one or more of the following: force vector data received from each force sensor, associated weighing factors for each force sensor, a gravity factor determined from a latitude and an altitude at a destination location, a foot rest panel mounting offset, and angle information received from the angle sensor.

17. The control system of claim 12 , wherein the one or more processors are configured to receive directional data from the angle sensor to calibrate the angle sensor and determine an angle of the frame assembly with respect to a horizontal reference plane.

18. The control system of claim 12 , wherein the one or more processors are configured to calibrate the angle senso

Assignees

• Ngoh Liew Chooi
• Yuanqiang Wen
• Liko Res & Dev Ab

Inventors

• Ngoh Liew Chooi
• Yuanqiang Wen

Classifications

• A61G7/108 Primary

  Weighing means · CPC title

• A61G7/1067

  for adjustable bases · CPC title

• A61G7/1017 Primary

  Pivoting arms, e.g. crane type mechanisms · CPC title

• G01G19/52

  Weighing apparatus combined with other objects, e.g. furniture (with walking sticks A45B3/08) · CPC title

• G01G19/445

  in a horizontal position · CPC title