Automatic measuring device

Patent metadata

Field	Value
Publication number	US-11466971-B2
Application number	US-202117227828-A
Country	US
Kind code	B2
Filing date	Apr 12, 2021
Priority date	May 28, 2020
Publication date	Oct 11, 2022
Grant date	Oct 11, 2022

Abstract

There is provided an automatic measurement device that automates a contact type measuring instrument, which is inexpensive and good usability. An automatic measurement device includes a measuring instrument support base portion that supports a measuring instrument and a workpiece holding base portion that holds a workpiece in a measurement region of the measuring instrument. The measuring instrument support base portion includes a measuring instrument holder that holds a fixed element of the measuring instrument and an automatic operation unit attachable to and detachable from the measuring instrument. The automatic operation unit is configured to automate advance and retreat of the movable element of the measuring instrument by a power from a motor.

First claim

The invention claimed is:

1. An automatic measurement device that automatically measures a workpiece using a measuring instrument, the measuring instrument measuring a dimension of the workpiece, the automatic measurement device comprising:
the measuring instrument;
a measuring instrument support base portion that supports the measuring instrument; and
a workpiece holding base portion that holds the workpiece in a measurement region of the measuring instrument, wherein
the measuring instrument includes:
a fixed element;
a movable element provided to be displaceable with respect to the fixed element, the movable element advancing and retreating to approach and separate from the workpiece; and
a displacement detection unit configured to detect the displacement of the movable element, wherein
the measuring instrument support base portion includes:
a measuring instrument holder that holds the fixed element of the measuring instrument; and
an automatic operation unit attachable to and detachable from the measuring instrument, the automatic operation unit being configured to automate the advance and the retreat of the movable element by a power from a motor.

2. The automatic measurement device according to claim 1 , wherein when the workpiece abuts on the movable element, at least one of the workpiece held to the workpiece holding base portion and the measuring instrument held to the measuring instrument holder changes a position and a posture at a pressure equal to or less than a predetermined measurement pressure preset to the measuring instrument such that the workpiece and the movable element are held with abutment surfaces mutually in close contact.

3. The automatic measurement device according to claim 2 , wherein the workpiece holding base portion is a workpiece placement base on which the workpiece is placed.

4. The automatic measurement device according to claim 2 , wherein
the workpiece holding base portion includes workpiece holding means that holds the workpiece, and
one of the workpiece holding means and the measuring instrument holder is provided so as to permit a relative displacement with respect to another.

5. The automatic measurement device according to claim 1 , wherein
the measuring instrument includes an operation unit originally for a manual operation, and the operation unit is configured to advance and retreat the movable element by a manual rotation operation or a manual pushing operation, and
the automatic operation unit is attachable to/detachable from the operation unit, and the automatic operation unit is configured to operate the operation unit by the power from the motor to automate the advance and the retreat of the movable element.

6. The automatic measurement device according to claim 1 , wherein
the measuring instrument is a micrometer,
the micrometer includes:
a U-shaped frame as the fixed element including an anvil at one end inside a U shape thereof; and
a spindle as the movable element provided on another end side of the U-shaped frame, the spindle being provided to be axially advanceable and retreatable with respect to the anvil, and
the automatic operation unit includes:
the motor; and
a power transmission unit configured to directly or indirectly connect an output shaft of the motor to the spindle to convert the power from the motor into the advance/retreat of the spindle.

7. The automatic measurement device according to claim 6 , wherein
the automatic operation unit is provided such that a position is changeable in a direction orthogonal to a center axis of the spindle such that a rotation axis of a rotor of the motor is collinear with the center axis of the spindle.

8. The automatic measurement device according to claim 6 , wherein
the micrometer includes a thimble disposed at another end of the spindle on another end side of the U-shape frame, and a rotation operation is performed on the thimble originally by a finger, and
the power transmission unit includes:
an anchor ring fitted to an outside of the thimble;
a rotation plate provided to rotate in synchronization with a rotation shaft of a rotor of the motor; and
a transmission link rod disposed parallel to a center axis of the spindle, the transmission link rod having one end fixed to the anchor ring and another end fixed to the rotation plate, the transmission link rod rotating with the center axis of the spindle as a center of the rotation to transmit the rotation of the rotation plate to the anchor ring.

9. The automatic measurement device according to claim 8 , comprising
a constant pressure mechanism provided between the thimble and the spindle, the constant pressure mechanism being configured such that when a preset load is applied to the spindle, the constant pressure mechanism disengaging the thimble and the spindle to cause the thimble to idle with respect to the spindle.

10. The automatic measurement device according to claim 6 , wherein
the automatic operation unit includes a motor controller configured to control a rotation of the motor,
the motor controller has a torque detection function of the motor,
the motor controller has, as a control mode of a motor rotation number:
a high-speed rotation mode as a high-speed rotation; and
a low-speed rotation mode at a speed lower than a rotation speed in the high-speed rotation mode,
when a motor rotation direction in a direction of advancing the spindle is defined as a forward rotation, and when the motor rotation direction in a direction of retreating the spindle is defined as a reverse direction, the motor controller is configured:
to advance the spindle in the forward rotation in the high-speed rotation mode;
such that when the torque detection function detects an abutment between the spindle and the workpiece, the motor controller retreats the spindle in the reverse rotation in the high-speed rotation mode by a predetermined first rotation number;
to subsequently advance the spindle in the forward rotation in the low-speed rotation mode by the first rotation number, and subsequently further drive the motor in the forward rotation in the low-speed rotation mode by a predetermined second rotation number; and
afterwards, to drive the motor in the forward rotation in the high-speed rotation mode by a predetermined third rotation number.

11. An automatic measurement system comprising:
the automatic measurement device according to claim 1 ; and
workpiece conveyance means configured to pick up the workpieces and sequentially convey the workpieces to the workpiece holding base portion.

12. An automatic measurement device that automates a measuring instrument, the measuring instrument causing a movable element to be in contact with a workpiece to measure a dimension of the workpiece, the automatic measurement device comprising:
a measuring instrument support base portion that supports the measuring instrument; and
a workpiece holding base portion that holds the workpiece in a measurement region of the measuring instrument, wherein
the measuring instrument support base portion includes:
a measuring instrument holder that holds a fixed element of the measuring instrument; and
an automatic operation unit attachable to and detachable from the measuring instrument, the automatic operation unit being configured to automate the advance and the retreat of the movable element by a power from a motor.

Assignees

• Mitutoyo Corp

Inventors

• Yamaji Masashi
• Morimoto Hideyuki
• Sorada Kazuma

Classifications

• G01B3/18

  Micrometers · CPC title

• G01B5/20

  for measuring contours or curvatures · CPC title

• G01B3/008

  Arrangements for controlling the measuring force · CPC title

• G01B5/08 Primary

  for measuring diameters {(G01B5/0035 takes precedence; measuring radius of curvature G01B5/213)} · CPC title

• G01B5/02 Primary

  for measuring length, width or thickness (G01B5/004, G01B5/08 take precedence) · CPC title