Hybrid spring and electric motor tape rule

Patent metadata

Field	Value
Publication number	US-10422616-B2
Application number	US-201715643565-A
Country	US
Kind code	B2
Filing date	Jul 7, 2017
Priority date	Jul 7, 2017
Publication date	Sep 24, 2019
Grant date	Sep 24, 2019

Abstract

A tape rule having a housing, a hub, a reel, a tape, a spring, and a motor. The hub and reel are rotatably mounted within the housing. The tape is wound around the reel. The spring is wound around the hub and is attached to at least one of the reel and the tape. The motor is disposed adjacent to the hub and is configured, when activated, to rotate the hub to adjust an amount by which the spring is wound around the hub.

First claim

What is claimed is:

1. A tape rule comprising:
a housing;
a hub rotatably mounted within the housing;
a reel rotatably mounted within the housing;
a tape wound around the reel;
a spring wound around the hub and attached to at least one of the reel and the tape, wherein the hub comprises an axial member around which the spring is wound, and wherein the axial member of the hub is disposed within the reel; and
a motor disposed adjacent to the hub and configured, when activated, to rotate the hub to wind or unwind the spring relative to the hub to adjust an amount by which the spring is wound around the hub.

2. The tape rule of claim 1 , wherein the amount by which the spring is wound around the hub is configured to increase as the tape is extracted from the housing, and wherein the motor is configured, when activated, to rotate the hub in a direction that unwinds the spring relative to the hub to decrease the amount by which the spring is wound around the hub.

3. The tape rule of claim 2 , wherein the tape rule is configured, during extraction of the tape from the housing,
to determine a parameter value indicative of the amount by which the spring is wound around the hub,
to determine whether the parameter value has reached or exceeds a defined threshold, and
in response to a determination that the parameter value has reached or exceeds the defined threshold, activate the motor to unwind the spring relative to the hub.

4. The tape rule of claim 3 , wherein the parameter value is a value of a force or torque exerted by the spring on the hub, or is a value of a length of the tape that has been extracted from the housing.

5. The tape rule of claim 4 , further comprising a battery, wherein the motor is configured to draw current from the battery to maintain the hub in a substantially rotationally fixed state relative to the motor as the tape is extracted from the housing, wherein the tape rule is configured to determine the value of the force or torque by: determining an amount of the current being drawn by the motor from the battery to maintain the hub in the substantially rotationally fixed state as the tape is extracted from the housing, and determining the value of the force or torque based on the amount of the current being drawn by the motor to maintain the hub in the substantially rotationally fixed state.

6. The tape rule of claim 3 , wherein the tape rule is further configured, after activating the motor to unwind the spring,
to determine whether the parameter value has fallen below the defined threshold by at least a defined buffer amount, and
in response to a determination that the parameter value has fallen below the defined threshold by at least the defined buffer amount, to deactivate the motor.

7. The tape rule of claim 3 , wherein the defined threshold corresponds to the spring being in a fully wound state in which the spring is substantially non-compressible.

8. The tape rule of claim 3 , wherein the defined threshold is reached when less than half of a total length of the tape has been extracted from the housing.

9. The tape rule of claim 1 , wherein the amount by which the spring is wound around the hub is configured to decrease as the tape is retracted into the housing, and wherein the motor is configured, when activated, to rotate the hub in a direction that winds the spring relative to the hub to increase the amount by which the spring is wound around the hub.

10. The tape rule of claim 9 , wherein the tape rule is further configured, during retraction of the tape into the housing:
to determine a parameter value indicative of the amount by which the spring is wound around the hub,
to determine whether the parameter value has reached or fallen below a defined threshold, and
in response to a determination that the parameter value has reached or fallen below the defined threshold, activate the motor to wind the spring relative to the hub, and
in response to a determination that the parameter value has subsequently risen above the defined threshold by at least a defined buffer amount, to deactivate the motor.

11. The tape rule of claim 1 , wherein the tape rule is configured to determine a parameter value indicative of the amount by which the spring is wound around the hub, and is configured, after the parameter value has reached or exceeded a first defined threshold, to maintain the parameter value in a range between the first defined threshold and a second defined threshold lower than the first defined threshold by causing the motor to rotate the hub in a first direction to unwind the spring or causing the motor to rotate the hub in a second direction to wind the spring to adjust the parameter value.

12. The tape rule of claim 1 , further comprising a clutch disposed between the motor and the hub, wherein the clutch is configured to selectively disengage the motor from the hub based on a value of a force or torque exerted by the hub on the motor.

13. The tape rule of claim 1 , further comprising a user input element disposed on or in the housing and configured to receive a user input, wherein the tape rule is configured to activate the motor in response to the user input element receiving the user input.

14. The tape rule of claim 1 , wherein, during retraction of tape into the housing, the spring is configured to exert a force or torque on the reel or on the tape in a second direction, and wherein the tape rule has a mode that, when pre-set or manually activated, causes the tape rule to activate the motor to rotate the hub in a first and opposite direction to reduce the force or torque exerted by the spring on the reel or on the tape during at least part of the retraction of the tape into the housing.

15. The tape rule of claim 14 , wherein the mode is an auto slow-down mode that, when pre-set or manually activated, causes the tape rule to determine whether a parameter value indicative of the force or torque being applied by the spring on the reel or tape has reached or exceeds a defined threshold, and wherein the motor is activated to rotate the hub in the first direction during the retraction of the tape in response to a determination that the parameter value has reached or exceeds the defined threshold.

16. A tape rule comprising:
a housing;
a reel rotatably mounted within the housing;
a tape wound around the reel;
a motor connected to the reel, wherein the tape is configured to exert a force or torque on the reel during extraction of the tape from the housing,
wherein the tape rule is configured, during extraction of the tape from the housing:
to determine whether the force or torque exerted by the tape on the reel has reached or exceeds a defined threshold, and
in response to a determination that the force or torque exerted by the tape on the reel has reached or exceeds the defined threshold, to activate the motor to output rotation to reduce the force or torque exerted by the tape on the reel.

17. The tape rule of claim 16 , wherein the force or torque exerted by the tape on the reel causes or will cause the reel to rotate in a first direction, and wherein the motor, when activated, is also configured to rotate the reel in the first direction.

18. The tape rule of claim 17 , further comprising a torque sensor disposed adjacent to the reel or to the motor and configured to measure a torque being exerted by the tape on the reel.

19. The tape rule of claim 18 , wherein the tape rule is configured to activate the motor in a second and opposite direction to retract the tape into the housing.

Assignees

• Stanley Black & Decker Inc

Inventors

• Orsini Antony
• Eidinger Bruce

Classifications

• G01B3/1043

  Details of internal structure thereof, e.g. means for coupling separately moulded casing halves · CPC title

• G01B2003/103

  operated by springs · CPC title

• G01B3/1005 Primary

  Means for controlling winding or unwinding of tapes · CPC title

• G01B2003/1028

  operated by electric motors · CPC title

• F16F1/121

  adjustable, e.g. to modify spring characteristics · CPC title