Valve device

1. A valve device configured to perform at least one of adjusting a flow rate of fluid and changing a flow passage of the fluid, comprising:

a housing that has a fluid inlet, through which the fluid enters the housing, and a fluid outlet, through which the fluid exits from the housing;

a valve body that is rotatably placed at an inside of the housing and has a flow inlet, which is formed at a location that corresponds to the fluid inlet, and a flow outlet, which is formed at a location that corresponds to the fluid outlet;

a sleeve that is placed at the fluid outlet of the housing and forms a flow passage, into which the fluid is outputted from an inside space of the valve body through the flow outlet; and

a seat member that is placed between an outer wall of the valve body and an end portion of the sleeve located on a side where the valve body is placed while the seat member slidably contacts the outer wall of the valve body, wherein:

the valve device is configured such that the fluid, which enters from the fluid inlet of the housing into the inside of the housing, flows from the flow inlet of the valve body toward the inside space of the valve body and is limited from flowing into a space formed between an inner wall of the housing and the outer wall of the valve body;

the fluid inlet of the housing and the flow inlet of the valve body are both located at one side in an axial direction of a rotational axis of the valve body; and

an inner diameter of the fluid inlet of the housing is smaller than an outer diameter of an end portion of the valve body located on a side where the flow inlet is placed.

2. The valve device according to claim 1 , wherein the inner diameter of the fluid inlet of the housing is smaller than the outer diameter of the end portion of the valve body located on the side where the flow inlet is placed, and the inner diameter of the fluid inlet of the housing is larger than an inner diameter of the end portion of the valve body located on the side where the flow inlet is placed.

3. The valve device according to claim 1 , wherein:

the fluid inlet of the housing and the flow inlet of the valve body are both located at one side in an axial direction of a rotational axis of the valve body; and

an inner wall of the fluid inlet of the housing is shaped in a tapered form that has an inner diameter progressively reduced from an opposite side, which is opposite to the flow inlet, toward the flow inlet.

4. A valve device configured to perform at least one of adjusting a flow rate of fluid and changing a flow passage of the fluid, comprising:

a housing that has a fluid inlet, through which the fluid enters the housing, and a fluid outlet, through which the fluid exits from the housing;

a valve body that is rotatably placed at an inside of the housing and has a flow inlet, which is formed at a location that corresponds to the fluid inlet, and a flow outlet, which is formed at a location that corresponds to the fluid outlet;

a sleeve that is placed at the fluid outlet of the housing and forms a flow passage, into which the fluid is outputted from an inside space of the valve body through the flow outlet; and

a seat member that is placed between an outer wall of the valve body and an end portion of the sleeve located on a side where the valve body is placed while the seat member slidably contacts the outer wall of the valve body, wherein:

the valve device is configured such that the fluid, which enters from the fluid inlet of the housing into the inside of the housing, flows from the flow inlet of the valve body toward the inside space of the valve body and is limited from flowing into a space formed between an inner wall of the housing and the outer wall of the valve body;

the fluid inlet of the housing is formed at a portion of the housing, which is positioned relative to a rotational axis of the valve body in a direction perpendicular to the rotational axis of the valve body;

the flow inlet of the valve body is formed at a portion of the valve body, which is placed in an axial direction of the rotational axis;

the valve device comprises a projection that is located on an opposite side of the rotational axis of the valve body, which is diametrically opposite to the fluid inlet, wherein the projection projects from the inner wall of the housing toward the rotational axis of the valve body beyond an outer peripheral portion of the valve body; and

the projection is configured to limit the fluid, which enters from the fluid inlet of the housing into the inside of the housing, from flowing into the space formed between the inner wall of the housing and the outer wall of the valve body.

5. The valve device according to claim 4 , comprising an outlet pipe forming member that is placed at an outside of the housing, wherein:

the projection extends from the outlet pipe forming member through a hole of the housing and projects from the inner wall of the housing toward the rotational axis of the valve body beyond the outer peripheral portion of the valve body.

6. A valve device configured to perform at least one of adjusting a flow rate of fluid and changing a flow passage of the fluid, comprising:

a housing that has a fluid inlet, through which the fluid enters the housing, and a fluid outlet, through which the fluid exits from the housing;

a valve body that is rotatably placed at an inside of the housing and has a flow inlet, which is formed at a location that corresponds to the fluid inlet, and a flow outlet, which is formed at a location that corresponds to the fluid outlet;

a sleeve that is placed at the fluid outlet of the housing and forms a flow passage, into which the fluid is outputted from an inside space of the valve body through the flow outlet; and

a seat member that is placed between an outer wall of the valve body and an end portion of the sleeve located on a side where the valve body is placed while the seat member slidably contacts the outer wall of the valve body, wherein:

the valve device is configured such that the fluid, which enters from the fluid inlet of the housing into the inside of the housing, flows from the flow inlet of the valve body toward the inside space of the valve body and is limited from flowing into a space formed between an inner wall of the housing and the outer wall of the valve body;

the fluid inlet of the housing and the flow inlet of the valve body are both located at one side in an axial direction of a rotational axis of the valve body; and

an inner wall of the fluid inlet of the housing is shaped in a tapered form that has an inner diameter progressively reduced from an opposite side, which is opposite to the flow inlet, toward the flow inlet.