US 12,291,828 B2
Work machine
Yoshitaka Ota, Wako (JP); Hajime Yoshimura, Wako (JP); Yuta Kimura, Wako (JP); and Atsushi Moroi, Wako (JP)
Assigned to HONDA MOTOR CO., LTD., Tokyo (JP)
Filed by HONDA MOTOR CO., LTD., Tokyo (JP)
Filed on Mar. 15, 2022, as Appl. No. 17/695,368.
Claims priority of application No. 2021-045145 (JP), filed on Mar. 18, 2021.
Prior Publication US 2022/0298736 A1, Sep. 22, 2022
Int. Cl. E01H 5/09 (2006.01)
CPC E01H 5/098 (2013.01) 6 Claims
OG exemplary drawing
 
1. A work machine comprising:
a drive source;
a transmission mechanism configured to transmit rotation of the drive source;
a driven rotary member configured to rotate a driven shaft in accordance with the rotation transmitted by the transmission mechanism; and
a coupling mechanism configured to couple a work rotation shaft coupled to a working section and the driven shaft to each other via a friction member and transmit the rotation of the driven shaft to the work rotation shaft,
wherein the work machine includes:
a drive rotation speed detector configured to detect a signal indicating the rotation of the drive source;
a work rotation speed detector configured to detect a signal indicating rotation of the work rotation shaft; and
a control device configured to, on the basis of comparison between signals acquired from the drive rotation speed detector and the work rotation speed detector, stop the drive source in a case where there is a rotation speed difference between the driven shaft in a rotating state due to power transmission from the drive source and the work rotation shaft,
wherein the work rotation speed detector includes:
a detection target member configured to rotate together with the work rotation shaft; and
a sensor mounting member configured to hold a detection sensor configured to detect rotation of the detection target member,
the sensor mounting member is coupled to a machine body frame of the work machine,
wherein the detection target member includes:
an inner peripheral portion fixed to a stepped portion formed in a part of an outer peripheral portion of the work rotation shaft;
a flat portion provided to extend from the inner peripheral portion in a radial direction of the work rotation shaft;
a first inclined portion formed to be inclined toward the detection sensor from an end portion of the flat portion; and
a detection target pulser portion provided to extend from an end portion of the first inclined portion in the radial direction of the work rotation shaft, and
the detection sensor detects a signal derived from rotation of the detection target pulser portion.