Gear pump and image recording apparatus
AssigneeSeiko Epson Corporation
InventorsNoritaka Mitsuo, Masaaki Ando
Life of this patent
Estimating the term…
Abstract
To reduce frictional heat generated between a rotation shaft and a bearing portion in a gear pump in which the rotation shaft having a gear mounted thereon is received by the bearing portion and an image recording apparatus having the gear pump. Provided is a gear pump which has a rotation shaft, a bearing portion which receives the rotation shaft, and a gear which is mounted on the rotation shaft and rotates with the rotation shaft, in such a manner that the gear feeds liquid. Furthermore, at least either a concave portion or a convex portion is provided in at least either the rotation shaft or the bearing portion.
Claims16
A gear pump comprising:
- a rotation shaft;
- a bearing portion which defines a recess that receives a terminal portion of the rotation shaft, the bearing portion also including a separator disposed in the recess so as to be positioned between the terminal portion of the shaft and a bottom of the recess;
- and
- a gear which is mounted on the rotation shaft and rotates with the rotation shaft, in such a manner that the gear feeds liquid,
- wherein a surface pattern comprising at least either a concave portion or a convex portion is provided in the separator of the bearing portion, and
- wherein, when the rotation shaft rotates, at least either the concave portion or the convex portion causes a dynamic pressure to be generated in liquid in a portion between the rotation shaft and the bearing portion, and thus the rotation shaft and the bearing portion move away from each other due to the dynamic pressure.
A gear pump comprising:
- a rotation shaft;
- a bearing portion which defines a recess that receives a terminal portion of the rotation shaft, the bearing portion also including a separator disposed in the recess so as to be positioned between the terminal portion of the shaft and a bottom of the recess;
- and
- a gear which is mounted on the rotation shaft and rotates with the rotation shaft, in such a manner that the gear feeds liquid,
- wherein a surface pattern comprising at least either a concave portion or a convex portion is provided in the separator of the bearing portion.
An image recording apparatus comprising:
- a discharge portion which discharges liquid onto a recording medium;
- and
- a gear pump which supplies the liquid to the discharge portion,
- wherein the gear pump has a rotation shaft, a bearing portion which defines a recess that receives a terminal portion of the rotation shaft, the bearing portion also including a separator disposed in the recess so as to be positioned between the terminal portion of the shaft and a bottom of the recess, and a gear which is mounted on the rotation shaft and rotates with the rotation shaft, in such a manner that the gear feeds liquid,
- wherein a surface pattern comprising at least either a concave portion or a convex portion is provided in the separator of the bearing portion, and
- wherein, when the rotation shaft rotates, at least either the concave portion or the convex portion causes a dynamic pressure to be generated in liquid in a portion between the rotation shaft and the bearing portion, and thus the rotation shaft and the bearing portion move away from each other due to the dynamic pressure.
Dependencies are inferred from the claim text.