EGR cooler bypass valve

Patent metadata

Field	Value
Publication number	US-10408170-B2
Application number	US-201815987411-A
Country	US
Kind code	B2
Filing date	May 23, 2018
Priority date	Jun 28, 2017
Publication date	Sep 10, 2019
Grant date	Sep 10, 2019

Abstract

In a casing, a cooler valve element is placed in a cooler flow passage, while a bypass valve element is placed in a bypass flow passage. The cooler valve element is adjacent and fixed to a first shaft end portion of a valve shaft. The bypass valve element is adjacent and fixed to a second shaft end portion of the valve shaft. A first bearing is provided between the casing and the first shaft end portion and a second bearing is provided between the casing and the second shaft end portion. A first seal member is placed, adjacent to the first bearing, and a second seal member is placed adjacent to a second bearing. A driven gear is fixed to a leading end of the first shaft end portion. The first bearing consists of a rolling bearing and the second bearing is formed of a slid bearing.

First claim

What is claimed is:

1. An EGR cooler bypass valve to be used together with an EGR cooler for cooling EGR gas and a bypass passage bypassing the EGR cooler, the EGR cooler bypass valve being configured to simultaneously adjust a flow rate of the EGR gas passing through the EGR cooler and a flow rate of the EGR gas passing through the bypass passage,
the EGR cooler bypass valve including:
a casing including a cooler flow passage through which the EGR gas having passed through the EGR cooler flows, and a bypass flow passage through which the EGR gas having passed through the bypass passage flows, the casing being configured such that the cooler flow passage and the bypass flow passage are separated by a partition wall;
a valve shaft placed in the casing so that the valve shaft extends across the cooler flow passage, the bypass flow passage, and the partition wall, and the valve shaft including a first shaft end portion and a second shaft end portion;
a cooler valve element placed in the cooler flow passage and provided integral with the valve shaft;
a bypass valve element placed in the bypass flow passage and provided integral with the valve shaft;
a first bearing provided between the casing and the first shaft end portion and configured to rotatably support the first shaft end portion;
a second bearing provided between the casing and the second shaft end portion and configured to rotatably support the second shaft end portion;
a first seal member placed near the first bearing and configured to seal between the first shaft end portion and the casing;
a second seal member placed near the second bearing and configured to seal between the second shaft end portion and the casing; and
a driven gear fixed to a leading end of the first shaft end portion to rotate the valve shaft, the driven gear constituting a speed reducing mechanism,

the EGR cooler bypass valve being configured to rotate the valve shaft through the driven gear to open and close the cooler valve element and the bypass valve element,
wherein the cooler flow passage and the cooler valve element are placed adjacent to the first shaft end portion and the bypass flow passage and the bypass valve element are placed adjacent to the second shaft end portion,
the first bearing consists of a rolling bearing to precisely support rotation of the first shaft end portion, and
the second bearing consists of a slide bearing to enhance heat radiation from the second shaft end portion to the casing.

2. The EGR cooler bypass valve according to claim 1 , wherein
the driven gear consisting of a resin gear, a metal connecting member is integrally provided in the resin gear, the leading end of the first shaft end portion is connected to the resin gear through the metal connecting member, and
the metal connecting member is provided with a heat-transfer reducing structure for reducing heat transfer from the first shaft end portion to the resin gear.

3. The EGR cooler bypass valve according to claim 1 , wherein the EGR cooler bypass valve includes a heat-radiation promoting unit placed on the first shaft end portion and between the first bearing and the first seal member to promote heat radiation from the first shaft end portion to the casing.

Assignees

• Aisan Ind

Inventors

• Kobayashi Masahiro
• Yoshioka Mamoru
• Takeuchi Mitsuru
• Suzuki Musashi
• Kawai Shinji
• Ito Naruto

Classifications

• F02M26/26 Primary

  characterised by details of the bypass valve · CPC title