Drive apparatus

Patent metadata

Field	Value
Publication number	US-9080653-B2
Application number	US-201314086251-A
Country	US
Kind code	B2
Filing date	Nov 21, 2013
Priority date	Nov 21, 2012
Publication date	Jul 14, 2015
Grant date	Jul 14, 2015

Abstract

A drive cam is rotated about a camshaft member upon application a drive torque of a drive source to the drive cam. A transmission device converts rotational motion of the drive cam into linear reciprocating motion and transmits the converted linear reciprocating motion to a control shaft member. The control shaft member is connected to a controlled subject and is linearly reciprocated together with the transmission device in an axial direction. A reverse input cutoff clutch transmits the drive torque, which is received from the drive source, to the drive cam. The reverse input cutoff clutch non-rotatably locks an output shaft of the drive source in response to a reverser input torque transmitted from the controlled subject through the drive cam.

First claim

What is claimed is:

1. A drive apparatus that adjusts a controlled variable of a controlled subject in response to an axial position of a control shaft member, the drive apparatus comprising:
a drive source that generates a drive torque;
a drive cam that is rotated about a camshaft member upon application the drive torque of the drive source to the drive cam, wherein a profile radius of the drive cam, which is a radial distance from a rotational center of the drive cam to an outer peripheral surface of the drive cam, is not uniform in a circumferential direction of the drive cam;
a transmission device that converts rotational motion of the drive cam into linear reciprocating motion upon rotation of the drive cam and transmits the converted linear reciprocating motion to the control shaft member;
the control shaft member that is connected to the controlled subject and is linearly reciprocated together with the transmission device in an axial direction upon the rotation of the drive cam; and
a reverse input cutoff clutch that transmits the drive torque, which is received from the drive source, to the drive cam, wherein the reverse input cutoff clutch non-rotatably locks an output shaft of the drive source in response to a reverser input torque transmitted from the controlled subject through the drive ca;
the transmission device includes:
a contact member that is placed on one side of a rotational center of the drive cam in a radial direction, wherein the contact member is urged by the controlled subject and thereby contacts the outer peripheral surface of the drive cam through a contact point; and
a support member that supports the contact member and is linearly reciprocated in a direction perpendicular to the camshaft member in response to a change in the profile radius of the drive cam at the contact point caused by the rotational motion of the drive cam;

the control shaft member is joined to the support member and is linearly reciprocated together with the support member in the axial direction;
the drive cam includes a plurality of holding sections, wherein a corresponding one of the plurality of holding sections contacts the contact member when a drive force of the drive source is stopped;
the drive apparatus further comprises a controller that controls a stop cam angle of the drive cam relative to a cam angle, which is a rotational angle of the drive cam from a reference axis of the drive cam, when the drive force of the drive source is stopped;
each of the plurality of holding sections is set such that a size of an angular range from a minimum cam angle to a maximum cam angle of the holding section is equally set in each of the plurality of holding sections, and an amount of change in the profile radius relative to an amount of change in the cam angle in the angular range of the holding section is equally set in each of the plurality of holding sections; and
the controller sets a corresponding predetermined value as an angular difference, which is a difference from the minimum cam angle to the stop cam angle, in each of the plurality of holding sections, and the corresponding predetermined value corresponds to an individual relative position of the drive apparatus relative to the controlled subject.

2. The drive apparatus according to claim 1 , further comprising a speed reducing mechanism that reduces a rotational speed of rotation transmitted from the drive source and transmits the rotation of the reduced rotational speed to the drive cam, wherein the reverse input cutoff clutch is placed between the drive source and the speed reducing mechanism.

3. The drive apparatus according to claim 2 , wherein the reverse input cutoff clutch is coaxial with the output shaft of the drive source.

4. The drive apparatus according to claim 1 , wherein the drive source is an electric motor.

5. The drive apparatus according to claim 1 , wherein the amount of change in the profile radius relative to the amount of change in the cam angle is constant in each of the plurality of holding sections.

Assignees

• Denso Corp

Inventors

• Suzuki Yasuyoshi
• Takahashi Yuuya
• Takahara Toshihiro

Classifications

• F01L13/00

  Modifications of valve-gear to facilitate reversing, braking, starting, changing compression ratio, or other specific operations · CPC title

• Y10T74/18296

  Cam and slide · CPC title

• F16H25/14 Primary

  with reciprocation perpendicular to the axis of rotation (crank or eccentric gearings without swinging connecting-rod F16H21/36) · CPC title

• F16H53/06

  Cam-followers (F16H53/08 takes precedence) · CPC title

• F01L1/344

  changing the angular relationship between crankshaft and camshaft, e.g. using helicoidal gear · CPC title