Patent Description:
<CIT> discloses a vehicle vent valve assembly to prevent excessive air pressure in a passenger compartment of a vehicle. The vent valve assembly includes a vent valve which is movable between a closed condition blocking fluid (air) flow from a passenger compartment of the vehicle and an open condition. An actuator assembly is provided to operate the vent valve from the closed condition to the open condition. The vent valve is urged toward the closed condition by a closing spring. A damper is connected with the vent valve to delay closing of the vent valve. A force transmitting member in the actuator assembly is connected with the vent valve by a slide connection that enables relative movement to occur between the vent valve and the force transmitting member.

An operator cab for work vehicles such as dump trucks operating at mining sites or civil engineering sites needs to have high airtightness in order to prevent dust entry from an outside area and to maintain an indoor temperature adjusted by an air conditioner. <CIT> discloses a configuration in which a ventilation port formed in an operator cab performs an opening operation when an opening motion of a door is detected, and the ventilation port performs a closing operation when a closing motion of the door is detected. In this configuration, when the door of the operator cab is closed, air inside the operator cab flows out through the ventilation port, thereby preventing an instantaneous increase in an air pressure inside the operator cab. In this manner, the door of the operator cab can be closed with a weak force.

In a configuration of <CIT>, it is necessary to use electrical means such as a sensor or a solenoid in order to detect opening and closing motions of the door and open and close the ventilation port. However, the work vehicle is operated at a site where there is a lot of dust, and many vehicle vibrations are generated during an operation. Accordingly, the electrical means needs to be reliably operated under a harsh environment. Therefore, it is necessary to take measures for durability of the electrical means, thereby causing a problem in that the costs for manufacturing the operator cab increase.

The present invention is made in view of the above-described problems, and an object thereof is to provide an operator cab for work vehicles, which is capable of easily closing a door of the operator cab at a low cost and capable of maintaining airtightness of the operator cab.

According to an aspect of the present invention, an operator cab for work vehicles comprises an operator cab body that forms a doorway and a ventilation port, a door that is configured to open and close the doorway, a lid portion that is configured to open and close the ventilation port, a link mechanism that connects the door and the lid portion to each other so that the lid portion is opened when the door is opened and the lid portion is closed when the door is closed, and a closing timing adjustment unit that stops a closing motion of the lid portion in a first stage of a motion of closing the door and that performs the closing motion of the lid portion in a second stage of the motion of closing the door after the first stage. The link mechanism includes a door-side link swingably connected to the door so as to be centered on a first end portion of the door-side link, and a lid-side link swingably connected to the lid portion so as to be centered on a first end portion of the lid-side link, a second end portion of which being swingably connected to a second end portion of the door-side link. The closing timing adjustment unit includes a slot hole formed in the second end portion of the door-side link so as to extend in a longitudinal direction of the door-side link, and a slot projection formed in the second end portion of the lid-side link, inserted into the slot hole, being movable in a longitudinal direction of the slot hole in the first stage, and reaching an end in the longitudinal direction of the slot hole in the second stage. The closing timing adjustment unit further includes a first projection portion fixed to the operator cab body, and a second projection portion provided in the lid-side link and pressed against the first projection portion toward the lid portion side to restrict a movement of the lid-side link, and, when the slot projection reaches the end in the longitudinal direction of the slot hole, pressing of the second projection portion against the first projection portion is released.

According to the present invention, a door of an operator cab can be easily closed at a low cost, and airtightness of the operator cab can be maintained.

Hereinafter, an embodiment of the present invention will be described in detail with reference to <FIG>. An operator cab according to the present embodiment includes a dump truck <NUM> illustrated in <FIG>. First, the dump truck <NUM> will be described.

As illustrated in <FIG>, the dump truck <NUM> is a work vehicle and is an articulated-type dump truck in which a front frame <NUM> and a rear frame <NUM> are connected to each other to freely swing so as to be centered on an axial line O.

The rear frame <NUM> is provided with a rear wheel <NUM> and a vessel <NUM>. The vessel <NUM> is provided to freely raised and lowered with respect to the rear frame <NUM>. The vessel <NUM> is driven by a hoist cylinder <NUM> which is a hydraulic actuator.

The front frame <NUM> is provided with a front wheel <NUM>, an operator cab <NUM> (cab), and an engine room <NUM>. The engine room <NUM> is disposed in front of the operator cab <NUM> and is covered with an exterior cover <NUM>.

As illustrated in <FIG>, the operator cab <NUM> includes an operator cab body <NUM>, a door <NUM>, a lid portion <NUM>, a link mechanism <NUM>, and a closing timing adjustment unit <NUM>.

As illustrated in <FIG> and <FIG>, the operator cab body <NUM> is formed in a box shape internally having a space. The operator cab body <NUM> has a doorway <NUM> for an operator of the work vehicle to enter and exit the operator cab <NUM>, and a ventilation port <NUM> for allowing air to flow into and flow out from the operator cab <NUM>.

The doorway <NUM> and the ventilation port <NUM> may be formed at any desired portion of the operator cab body <NUM>. In the present embodiment, the doorway <NUM> is formed in a side wall portion <NUM> of the operator cab body <NUM>. The ventilation port <NUM> is formed in a bottom wall portion <NUM> of the operator cab body <NUM>. That is, the ventilation port <NUM> is open on an inner surface 24a of the bottom wall portion <NUM>. The ventilation port <NUM> causes an internal space of the operator cab body <NUM> to communicate with an external space of the operator cab body <NUM>.

The ventilation port <NUM> may be formed at any desired position in the bottom wall portion <NUM>. The ventilation port <NUM> of the present embodiment is formed at a position which is not stepped on by the operator who enters and exits the operator cab <NUM>. Specifically, the ventilation port <NUM> is located at a distance from the doorway <NUM> in a direction (X-axis direction; hereinafter, also referred to as a first direction) orthogonal to an opening direction (Y-axis direction; hereinafter, also referred to as a second direction) of the doorway <NUM> along the inner surface 24a of the bottom wall portion <NUM>. The direction orthogonal to both the Y-axis direction and the X-axis direction is a height direction (Z-axis direction; hereinafter, also referred to as a third direction) of the operator cab body <NUM> orthogonal to the inner surface 24a of the bottom wall portion <NUM>.

As illustrated in <FIG>, the door <NUM> opens and closes the doorway <NUM> of the operator cab body <NUM>. The door <NUM> of the present embodiment is attached to the side wall portion <NUM> of the operator cab body <NUM> to be rotatable. A shaft <NUM> (door rotation shaft <NUM>) that rotates the door <NUM> with respect to the side wall portion <NUM> extends in the height direction (Z-axis direction) of the operator cab body <NUM>. The door rotation shaft <NUM> is located between the doorway <NUM> and the ventilation port <NUM> which are arranged in the first direction. The door <NUM> opens the doorway <NUM> of the operator cab body <NUM> by rotating to be separated outward of the operator cab body <NUM> from the doorway <NUM>.

As illustrated in <FIG> and <FIG>, the lid portion <NUM> opens and closes the ventilation port <NUM> of the operator cab body <NUM>. The lid portion <NUM> of the present embodiment is attached to the bottom wall portion <NUM> of the operator cab body <NUM> to be rotatable. A shaft <NUM> (lid portion rotation shaft <NUM>) that connects the lid portion <NUM> and the bottom wall portion <NUM> to each other to rotate the lid portion <NUM> with respect to the bottom wall portion <NUM> extends in the opening direction (Y-axis direction) of the doorway <NUM> along the inner surface 24a of the bottom wall portion <NUM>. The lid portion rotation shaft <NUM> is located between the doorway <NUM> and the ventilation port <NUM> which are arranged in the first direction. The lid portion <NUM> is disposed to overlap the inner surface 24a of the bottom wall portion <NUM>, thereby closing the ventilation port <NUM> of the operator cab body <NUM>. That is, the lid portion <NUM> closes the ventilation port <NUM> by performing a closing motion, thereby blocking the internal space of the operator cab body <NUM> and the external space of the operator cab body <NUM>. The lid portion <NUM> may be formed in any desired shape. The lid portion <NUM> of the present embodiment is formed in a flat plate shape having a rectangular shape in a plan view. One side of the lid portion <NUM> in a plan view is parallel to the lid portion rotation shaft <NUM>. In the following description, a direction orthogonal to a plate thickness direction of the lid portion <NUM> and away from the lid portion rotation shaft <NUM> may be referred to as a longitudinal direction of the lid portion <NUM> in some cases.

As illustrated in <FIG>, the link mechanism <NUM> connects the door <NUM> and the lid portion <NUM> to each other so that the lid portion <NUM> is opened when the door <NUM> is opened and the lid portion <NUM> is closed when the door <NUM> is closed. The link mechanism <NUM> of the invention includes a door-side link <NUM> and a lid-side link <NUM>. The door-side link <NUM> and the lid-side link <NUM> are formed to respectively extend linearly.

The door-side link <NUM> is swingably connected to the door <NUM> so as to be centered on a first end portion 31a in the longitudinal direction of the door-side link <NUM>. For example, the door-side link <NUM> may be directly connected to the door <NUM>. The door-side link <NUM> of the present embodiment is connected to the door <NUM> via a first link member <NUM> and a second link member <NUM> which configure the link mechanism <NUM> together with the door-side link <NUM>.

The first link member <NUM> is formed in an L-shape. The first link member <NUM> is swingably connected to the door <NUM> so as to be centered on a first end portion 33a in the longitudinal direction of the first link member <NUM>. The first link member <NUM> is swingable with respect to the door <NUM> so as to be centered on a first rotation shaft <NUM> parallel to the door rotation shaft <NUM>.

The second link member <NUM> is formed to extend linearly. The second link member <NUM> is swingably connected to a second end portion 33b of the first link member <NUM> so as to be centered on a first end portion 34a in the longitudinal direction of the second link member <NUM>. The first link member <NUM> and the second link member <NUM> is mutually swingable so as to be centered on a second rotation shaft <NUM> parallel to the door rotation shaft <NUM>.

The door-side link <NUM> of the present embodiment is swingably connected to a second end portion 34b of the above-described second link member <NUM> so as to be centered on the first end portion 31a in the longitudinal direction of the door-side link <NUM>. The door-side link <NUM> and the second link member <NUM> is mutually swingable so as to be centered on a third rotation shaft <NUM> extending in the second direction (Y-axis direction) orthogonal to the first direction along the inner surface 24a of the operator cab body <NUM>.

The first end portion 31a of the door-side link <NUM> is movable only in the first direction with respect to the operator cab body <NUM>. This point will be specifically described. As illustrated in <FIG> and <FIG>, a rail portion <NUM> is provided between the first end portion 31a of the door-side link <NUM> and the second end portion 34b of the second link member <NUM>. The rail portion <NUM> guides a movement of the first end portion 31a and the second link member <NUM> of the door-side link <NUM> only in the first direction. Specifically, the rail portion <NUM> has an elongated hole 38a extending in the first direction. The third rotation shaft <NUM> connecting the door-side link <NUM> and the second link member <NUM> to each other is inserted into the elongated hole 38a. In this manner, the first end portion 31a and the second link member <NUM> of the door-side link <NUM> are movable only in the first direction with respect to the operator cab body <NUM>. For example, the first end portion 31a and the second link member <NUM> of the door-side link <NUM> move toward the lid portion <NUM> side in the first direction in response to a motion of closing the door <NUM>.

The above-described rail portion <NUM> is fixed to the operator cab body <NUM>. Specifically, the rail portion <NUM> is fixed to the inner surface 24a of the bottom wall portion <NUM> via a slit-provided plate member <NUM> (to be described later).

As illustrated in <FIG> and <FIG>, the lid-side link <NUM> is swingably connected to the lid portion <NUM> so as to be centered on the first end portion 32a in the longitudinal direction of the lid-side link <NUM>. The lid-side link <NUM> is swingable with respect to the lid portion <NUM> around a fourth rotation shaft <NUM> extending in the second direction. The lid-side link <NUM> of the present embodiment is directly connected to the lid portion <NUM>. The first end portion 32a of the lid-side link <NUM> is connected to an intermediate portion in the longitudinal direction of the lid portion <NUM>.

As illustrated in <FIG>, the second end portion 32b of the lid-side link <NUM> is swingably connected to the second end portion 31b of the door-side link <NUM>. The door-side link <NUM> and the lid-side link <NUM> is mutually swingable so as to be centered on a fifth rotation shaft <NUM> extending in the second direction.

The door-side link <NUM> and the lid-side link <NUM> described above are sequentially arranged in the first direction from the door <NUM> side (doorway <NUM> side) toward the lid portion <NUM> side (ventilation port <NUM> side). In addition, the longitudinal direction of the door-side link <NUM> is inclined with respect to the inner surface 24a of the bottom wall portion <NUM> so that the second end portion 31b of the door-side link <NUM> is located farther away from the inner surface 24a of the bottom wall portion <NUM> than the first end portion 31a in the third direction.

The closing timing adjustment unit <NUM> stops a closing motion of the lid portion <NUM> in a first stage of a motion of closing the door <NUM> and performs the closing motion of the lid portion <NUM> in a second stage of the motion of closing the door <NUM> after the first stage. As illustrated in <FIG> and <FIG>, the closing timing adjustment unit <NUM> of the invention includes a slot hole <NUM> formed in the second end portion 31b of the door-side link <NUM>, and a slot projection <NUM> formed in the second end portion 32b of the lid-side link <NUM> and inserted into the slot hole <NUM>.

The slot hole <NUM> is formed to extend in the longitudinal direction of the door-side link <NUM>. The slot hole <NUM> is formed in an elongated hole shape when viewed in the second direction which is the plate thickness direction of the door-side link <NUM>. The slot hole <NUM> may be formed so that at least the slot projection <NUM> is inserted. The slot hole <NUM> of the present embodiment is formed to penetrate the door-side link <NUM> in the second direction.

The slot projection <NUM> is movable in the longitudinal direction of the slot hole <NUM> in a state of being inserted into the slot hole <NUM>. The slot projection <NUM> also serves as the above-described fifth rotation shaft <NUM>. That is, the slot projection <NUM> connects the door-side link <NUM> and the lid-side link <NUM> so as to be mutually swingable.

The slot projection <NUM> is movable in the longitudinal direction with respect to the slot hole <NUM> in the first stage of the motion of closing the door <NUM>. In addition, the slot projection <NUM> reaches an end <NUM> in the longitudinal direction of the slot hole <NUM> in the second stage of the motion of closing the door <NUM>. The end <NUM> of the slot hole <NUM> is located on the first end portion 31a side in the longitudinal direction of the door-side link <NUM>. In the following description, an end of the slot hole <NUM> located on a side opposite to the end <NUM> of the slot hole <NUM> in the longitudinal direction of the slot hole <NUM> will be referred to as a starting end <NUM> of the slot hole <NUM>.

As illustrated in <FIG> and <FIG>, the closing timing adjustment unit <NUM> of the invention further includes a first projection portion <NUM> fixed to the operator cab body <NUM>, and a second projection portion <NUM> provided in the lid-side link <NUM>. That is, the closing timing adjustment unit <NUM> of the present embodiment includes the slot hole <NUM>, the slot projection <NUM>, the first projection portion <NUM>, and the second projection portion <NUM>.

The first projection portion <NUM> of the present embodiment is fixed to the inner surface 24a of the bottom wall portion <NUM> via a slit-provided plate member <NUM> (to be described later). The first projection portion <NUM> is located between the inner surface 24a of the bottom wall portion <NUM> and the lid-side link <NUM> in a direction orthogonal to the inner surface 24a of the bottom wall portion <NUM> (Z-axis direction). In addition, the first projection portion <NUM> is located in an intermediate portion of a movement range of the second end portion 32b of the lid-side link <NUM> that moves in the first direction in conjunction with the opening and closing of the lid portion <NUM>.

The first projection portion <NUM> has a pressed surface <NUM> against which the second projection portion <NUM> is pressed toward the door <NUM> side in the first direction. For example, the pressed surface <NUM> may be orthogonal to the inner surface 24a of the bottom wall portion <NUM>. In the present embodiment, the pressed surface <NUM> is inclined from the door <NUM> side toward the lid portion <NUM> side in the first direction while being away from the inner surface 24a of the bottom wall portion <NUM> in the Z-axis direction. That is, the pressed surface <NUM> is a surface inclined at a predetermined angle with respect to the third direction.

In addition, the first projection portion <NUM> has an inclined surface <NUM> facing a side opposite to the pressed surface <NUM> in the first direction. The inclined surface <NUM> is inclined from the door <NUM> side to the lid portion <NUM> side in the first direction while being closer to the inner surface 24a of the bottom wall portion <NUM> in the Z-axis direction.

The second projection portion <NUM> of the present embodiment projects from the second end portion 32b of the lid-side link <NUM> toward the inner surface 24a of the bottom wall portion <NUM>.

The second projection portion <NUM> is pressed against the first projection portion <NUM> toward the lid portion <NUM> side, thereby restricting the movement of the lid-side link <NUM> in a closing direction of the lid portion <NUM>. For example, the second projection portion <NUM> may be pressed against the first projection portion <NUM> in a state where the door <NUM> and the lid portion <NUM> are completely opened. In the present embodiment, as illustrated in <FIG> and <FIG>, in the state where the door <NUM> and the lid portion <NUM> are completely opened, the second projection portion <NUM> is located on the door <NUM> side (side in the first direction) at a distance from the first projection portion <NUM>. Therefore, the second projection portion <NUM> is pressed against the first projection portion <NUM> in an intermediate stage of closing the lid portion <NUM>. Pressing of the second projection portion <NUM> against the first projection portion <NUM> is released when the above-described slot projection <NUM> reaches the end <NUM> of the slot hole <NUM> in the longitudinal direction by the movement of the door-side link <NUM>.

As illustrated in <FIG>, the operator cab <NUM> of the present embodiment further includes an elastic member <NUM>. The elastic member <NUM> is provided between the lid portion <NUM> and the operator cab body <NUM>. The elastic member <NUM> gives force in the closing direction of the lid portion <NUM> by an elastic force. The elastic member <NUM> may be a torsion spring or rubber. The elastic member <NUM> of the present embodiment is a coil spring. A first end of the elastic member <NUM> is attached to a facing surface 13a of the lid portion <NUM> that faces the ventilation port <NUM>. A second end of the elastic member <NUM> is attached to an attachment portion <NUM> of the operator cab body <NUM> which is disposed outside the ventilation port <NUM>. As illustrated in <FIG>, the attachment portion <NUM> may be formed separately from the bottom wall portion <NUM>, and then, may be fixed to the bottom wall portion <NUM>, or may be formed integrally with the bottom wall portion <NUM>, for example. Since the elastic member <NUM> is attached in this way, it is possible to prevent the elastic member <NUM> from hindering the lid portion <NUM> when the ventilation port <NUM> is closed. That is, the elastic member <NUM> has a characteristic of expanding and contracting (elastic force). Accordingly, a force that causes the elastic member <NUM> to contract is generated during the closing motion of the lid portion <NUM>. In this manner, the lid portion <NUM> tends to be closed by using the lid portion rotation shaft <NUM> as a rotation shaft. In addition, even in a state where the closing motion of the lid portion <NUM> is completed (state where the ventilation port <NUM> is closed by the lid portion <NUM>), the force that causes the elastic member <NUM> to contract is generated. In this manner, the lid portion <NUM> maintains a closed state of the ventilation port <NUM>.

When the elastic member <NUM> is a torsion spring or a coil spring, for example, the elastic member <NUM> may be attached to the lid portion rotation shaft <NUM> provided between the lid portion <NUM> and the operator cab body <NUM>.

As illustrated in <FIG>, the operator cab <NUM> of the present embodiment further includes the slit-provided plate member <NUM> fixed to the operator cab body <NUM> and interposed between the door-side link <NUM> and the lid-side link <NUM> in the second direction. The slit-provided plate member <NUM> has a slit <NUM> which penetrates in the second direction and into which the slot projection <NUM> (fifth rotation shaft <NUM>) is inserted. The slit <NUM> is formed to have a proper movement range of the slot projection <NUM> in conjunction with the opening and closing motions of the door <NUM>.

As illustrated in <FIG> and <FIG>, the operator cab <NUM> of the present embodiment further includes a support portion <NUM> fixed to the operator cab body <NUM>. The support portion <NUM> supports the second projection portion <NUM> from the inner surface 24a side of the bottom wall portion <NUM>. The support portion <NUM> is disposed at a position adjacent to the door <NUM> side with respect to the first projection portion <NUM> in the first direction. The support portion <NUM> has a support surface <NUM> extending in the first direction to be parallel to the inner surface 24a of the bottom wall portion <NUM> and supports the second projection portion <NUM>. The support surface <NUM> is located on the inner surface 24a side of the bottom wall portion <NUM> from the first projection portion <NUM> (particularly, the pressed surface <NUM>). The pressed surface <NUM> and the support surface <NUM> are continuously connected to each other. In <FIG> and <FIG>, the support portion <NUM> is formed integrally with the first projection portion <NUM>. However, the present invention is not limited thereto.

Next, a motion of the operator cab <NUM> of the present embodiment will be described with reference to <FIG> illustrate a simplified or changed structure of the operator cab <NUM> illustrated in <FIG> in order to describe the motion of the operator cab <NUM>. First, the motion when the door <NUM> is closed will be described with reference to <FIG>.

As illustrated in <FIG>, in a state where the door <NUM> and the lid portion <NUM> are completely opened, the second projection portion <NUM> is located on the door <NUM> side at a distance from the first projection portion <NUM>. In addition, the elastic force of the elastic member <NUM> causes the slot projection <NUM> to reach the starting end <NUM> of the slot hole <NUM>. Therefore, in the state where the door <NUM> and the lid portion <NUM> are completely opened, when the door <NUM> is closed as indicated by an arrow ND1, until the second projection portion <NUM> is pressed against the first projection portion <NUM> as illustrated in <FIG>, the closing motion of the lid portion <NUM> is performed as indicated by an arrow NC1 in conjunction with the closing motion of the door <NUM>. At this time, the second projection portion <NUM> may be located away from the support surface <NUM> of the support portion <NUM>, or may be disposed on the support surface <NUM> of the support portion <NUM>.

As illustrated in <FIG>, in a state where the second projection portion <NUM> is pressed against the first projection portion <NUM>, the movement of the lid-side link <NUM> is restricted in the closing direction of the lid portion <NUM>. That is, the closing motion of the lid portion <NUM> is stopped. In this state, when the closing motion of the door <NUM> is continuously performed as indicated by the arrow ND1, the first end portion 31a of the door-side link <NUM> moves toward the lid portion <NUM> side in the first direction as indicated by an arrow N. Therefore, the door-side link <NUM> moves with respect to the lid-side link <NUM> so that the slot projection <NUM> moves toward the end <NUM> from the starting end <NUM> of the slot hole <NUM>. In this manner, the closing motion of the door <NUM> can be performed while the closing motion of the lid portion <NUM> is stopped. The motion at this stage corresponds to the first stage of the above-described motion of closing the door <NUM>.

Thereafter, as illustrated in <FIG>, the closing motion of the door <NUM> indicated by the arrow ND1 is further continuously performed. In this manner, when the slot projection <NUM> reaches the end <NUM> of the slot hole <NUM>, pressing of the second projection portion <NUM> against the first projection portion <NUM> is released. Hereinafter, this point will be described in detail.

The longitudinal direction of the door-side link <NUM> is inclined with respect to the inner surface 24a of the bottom wall portion <NUM> so that the second end portion 31b of the door-side link <NUM> is located farther away from the inner surface 24a of the bottom wall portion <NUM> than the first end portion 31a. Therefore, after the slot projection <NUM> reaches the end <NUM> of the slot hole <NUM>, when the first end portion 31a of the door-side link <NUM> further moves toward the lid portion <NUM> side in the first direction in conjunction with the closing motion of the door <NUM>, the door-side link <NUM> rotates around the first end portion 31a so that the second end portion 31b of the door-side link <NUM> and the second end portion 32b of the lid-side link <NUM> including the second projection portion <NUM> move in a direction away from the inner surface 24a of the bottom wall portion <NUM>. In this manner, pressing of the second projection portion <NUM> against the first projection portion <NUM> is released.

In a case where the pressed surface <NUM> of the first projection portion <NUM> is inclined as illustrated in <FIG>, even when a swing center (that is, the fourth rotation shaft <NUM>) of the lid-side link <NUM> is located closer to the inner surface 24a of the bottom wall portion <NUM> than the first projection portion <NUM>, the second projection portion <NUM> pressed against the first projection portion <NUM> can be smoothly released.

When pressing of the second projection portion <NUM> against the first projection portion <NUM> is released in conjunction with the closing motion of the door <NUM>, the lid-side link <NUM> is allowed to move in the closing direction of the lid portion <NUM> (direction indicated by the arrow NC1). In this state, the slot projection <NUM> has reached the end <NUM> of the slot hole <NUM>. Accordingly, the lid-side link <NUM> can be pressed to the lid portion <NUM> side by the movement of the door-side link <NUM> in conjunction with the closing motion of the door <NUM> indicated by the arrow ND1. In this manner, the closing motion of the lid portion <NUM> is performed, and the ventilation port <NUM> can be closed by the lid portion <NUM>. In addition, according to the present embodiment, the lid portion <NUM> is given force in the closing direction of the lid portion <NUM> by the elastic force of the elastic member <NUM>. Therefore, the ventilation port <NUM> can be quickly and reliably closed by the lid portion <NUM>. The motion at this stage corresponds to the second stage of the above-described motion of closing the door <NUM>.

As described above, the motion of closing the door <NUM> and the lid portion <NUM> is completed.

In the second stage of the motion of closing the door <NUM>, the second projection portion <NUM> pressed against the first projection portion <NUM> may be released immediately before the doorway <NUM> of the operator cab body <NUM> is closed by the door <NUM> as illustrated in <FIG>, or may be released simultaneously with the closing of the doorway <NUM> of the operator cab body <NUM> which is performed by the door <NUM>, for example. When pressing of the second projection portion <NUM> against the first projection portion <NUM> is released immediately before the closing of the doorway <NUM> of the operator cab body <NUM>, the doorway <NUM> and the ventilation port <NUM> can be simultaneously closed. In addition, when the second projection portion <NUM> pressed against the first projection portion <NUM> is released simultaneously with the closing of the doorway <NUM> of the operator cab body <NUM>, the ventilation port <NUM> can be closed immediately after the doorway <NUM> is closed. That is, the ventilation port <NUM> is not closed earlier than the doorway <NUM>.

In a state where the door <NUM> and the lid portion <NUM> are completely closed, the second projection portion <NUM> is located on the lid portion <NUM> side from the pressed surface <NUM> of the first projection portion <NUM> in the first direction. The second projection portions <NUM> may be disposed at a distance above the inclined surface <NUM> of the first projection portions <NUM>. According to the present embodiment, the second projection portion <NUM> is disposed on the inclined surface <NUM> of the first projection portion <NUM> as illustrated in <FIG>.

Next, an operation when opening the door <NUM> will be described with reference to <FIG>.

In the state where the door <NUM> and the lid portion <NUM> are completely closed, when the door <NUM> is opened in a direction indicated by an arrow ND2 as illustrated in <FIG>, the first end portion 31a of the door-side link <NUM> is moved in the first direction by being pulled toward the door <NUM> side. In this manner, the slot projection <NUM> is located in the starting end <NUM> of the slot hole <NUM>, and the lid-side link <NUM> moves toward the door <NUM> side in the first direction together with the door-side link <NUM>. At this time, the second projection portion <NUM> of the lid-side link <NUM> is disposed on the inclined surface <NUM> of the first projection portion <NUM>. Accordingly, the movement of the above-described lid-side link <NUM> is not hindered by the first projection portion <NUM>. In conjunction with the movement of the lid-side link <NUM>, a force of opening the lid portion <NUM> acts on the lid portion <NUM> to overcome the elastic force of the elastic member <NUM>, and the lid portion <NUM> is opened in a direction indicated by an arrow NC2.

Thereafter, as illustrated in <FIG>, when the door <NUM> is further opened in the direction indicated by the arrow ND2 and the second projection portion <NUM> of the lid-side link <NUM> moves to the door <NUM> side from the first projection portion <NUM> in the first direction, the second projection portion <NUM> is disposed on the support surface <NUM> of the support portion <NUM> and is located on the door <NUM> side with respect to the pressed surface <NUM> of the first projection portion <NUM>. In this state, even when the lid portion <NUM> tries to move in the closing direction of the lid portion <NUM> due to the elastic force of the elastic member <NUM>, the second projection portion <NUM> is pressed against the pressed surface <NUM> of the first projection portion <NUM>. Therefore, it is possible to prevent the lid portion <NUM> and the door <NUM> from being closed due to the elastic force of the elastic member <NUM>.

Then, as illustrated in <FIG>, the door <NUM> is further opened in the direction indicated by the arrow ND2. In this manner, the door <NUM> and the lid portion <NUM> can be completely opened.

As described above, according to the operator cab <NUM> in the present embodiment, means for opening and closing the lid portion <NUM> in conjunction with the opening and closing of the door <NUM> is the link mechanism <NUM> which is mechanical means. Accordingly, compared to a case of using electrical means, the mechanical means is more durable against dust or vibrations of the dump truck. In this manner, costs for manufacturing the operator cab <NUM> can be minimized. In addition, the operator cab <NUM> according to the embodiment does not need a power source required for the electrical means. Accordingly, for example, the door <NUM> and the lid portion <NUM> can be easily closed without starting an engine to supply electric power to the electrical means.

In addition, according to the operator cab <NUM> of the present embodiment, in the first stage of the motion of closing the door <NUM>, the closing motion of the lid portion <NUM> is stopped by the closing timing adjustment unit <NUM>. That is, even when the closing motion of the door <NUM> is continuously performed, the lid portion <NUM> can be held in a widely opened state. Therefore, in the first stage, air inside the operator cab <NUM> can be efficiently discharged outward of the operator cab <NUM> from the ventilation port <NUM>. In this manner, it is possible to effectively prevent an increase in the air pressure inside the operator cab <NUM> when the door <NUM> is closed. Therefore, the door <NUM> of the operator cab <NUM> can be easily closed with a weak force.

In addition, according to the operator cab <NUM> of the present embodiment, in the second stage of the motion of closing the door <NUM> of the operator cab <NUM>, the closing motion of the lid portion <NUM> is performed by the closing timing adjustment unit <NUM> or the elastic member <NUM>. Therefore, the ventilation port <NUM> can be quickly closed by the lid portion <NUM> simultaneously with the door <NUM> closing the doorway <NUM> or immediately after the door <NUM> closes the doorway <NUM>. In this manner, it is possible to effectively prevent foreign substances such as dust existing outside the operator cab <NUM> from entering the inside of the operator cab <NUM> through the ventilation port <NUM>.

In addition, according to the operator cab <NUM> of the present embodiment, the closing timing adjustment unit <NUM> includes the slot hole <NUM> formed in the door-side link <NUM> and the slot projection <NUM> formed in the lid-side link <NUM>.

Therefore, in the first stage of the motion of closing the door <NUM>, even when the door-side link <NUM> moves in conjunction with the motion of closing the door <NUM>, the slot projection <NUM> of the lid-side link <NUM> moves in the longitudinal direction of the slot hole <NUM> of the door-side link <NUM>. In this manner, the door-side link <NUM> can be moved with respect to the lid-side link <NUM>. As a result, it is possible to prevent the lid-side link <NUM> from moving in conjunction with the motion of closing the door <NUM>. That is, the closing motion of the lid portion <NUM> can be stopped in the first stage of the motion of closing the door <NUM>.

On the other hand, in the second stage of the motion of closing the door <NUM>, the slot projection <NUM> of the lid-side link <NUM> reaches the end <NUM> in the longitudinal direction of the slot hole <NUM>. In this manner, the lid-side link <NUM> can be moved in conjunction with the movement of the door-side link <NUM>. That is, the closing motion of the lid portion <NUM> can be performed in conjunction with the motion of closing the door <NUM>.

In addition, according to the operator cab <NUM> of the present embodiment, in addition to the slot hole <NUM> and the slot projection <NUM>, the closing timing adjustment unit <NUM> further includes the first projection portion <NUM> fixed to the operator cab body <NUM>, and the second projection portion <NUM> provided in the lid-side link <NUM>. Therefore, in a state where the slot projection <NUM> does not reach the end <NUM> in the longitudinal direction of the slot hole <NUM>, the second projection portion <NUM> of the lid-side link <NUM> is pressed against the first projection portion <NUM>. In this manner, it is possible to reliably prevent the lid-side link <NUM> from moving together with the door-side link <NUM>. That is, it is possible to reliably prevent the closing motion of the lid portion <NUM> from being performed in the first stage of the motion of closing the door <NUM>.

In addition, according to the operator cab <NUM> of the present embodiment, the elastic member <NUM> that gives force to the lid portion <NUM> in the closing direction by using the elastic force is provided between the lid portion <NUM> and the operator cab body <NUM>. Therefore, the lid portion <NUM> can be quickly and reliably closed by the elastic force of the elastic member <NUM>. Since the lid portion <NUM> is quickly closed, it is possible to further prevent foreign substances such as dust from entering the inside of the operator cab <NUM> through the ventilation port <NUM>. Furthermore, even in a state where the lid portion <NUM> is closed, a closed state of the ventilation port <NUM> is maintained by the elastic force of the elastic member <NUM>. Accordingly, airtightness of the internal space of the operator cab <NUM> is maintained.

Hitherto, the embodiment according to the present invention has been described. However, the present invention is not limited thereto and can be appropriately modified within the scope as defined by the claims.

For example, the operator cab <NUM> of the present invention may not include the elastic member <NUM>. For example, the lid portion <NUM> may be provided so that gravity acts in the closing direction of the lid portion <NUM>. In this case, the lid portion <NUM> can be closed by using the gravity instead of the elastic force.

In addition, in the operator cab <NUM> of the present invention, the elastic force or the gravity does not have to act on the lid portion <NUM> in the closing direction of the lid portion <NUM>. Even in this case, when pressing of the second projection portion <NUM> against the first projection portion <NUM> is released, the slot projection <NUM> reaches the end <NUM> of the slot hole <NUM>. In this manner, the lid-side link <NUM> can be pushed to the lid portion <NUM> side due to the movement of the door-side link <NUM> in conjunction with the closing motion of the door <NUM>. In this manner, the closing motion of the lid portion <NUM> can be performed.

In the operator cab <NUM> according to the present invention, the ventilation port <NUM> may be formed in the side wall portion <NUM> of the operator cab body <NUM> as in the doorway <NUM>, for example. In this case, the link mechanism <NUM> or the closing timing adjustment unit <NUM> may be provided to correspond to an inner surface of the side wall portion <NUM> instead of the inner surface 24a of the bottom wall portion <NUM>.

Claim 1:
An operator cab (<NUM>) for work vehicles (<NUM>), comprising:
an operator cab body (<NUM>) that forms a doorway (<NUM>) and a ventilation port (<NUM>);
a door (<NUM>) that is configured to open and close the doorway (<NUM>);
a lid portion (<NUM>) that is configured to open and close the ventilation port (<NUM>);
a link mechanism (<NUM>) that connects the door (<NUM>) and the lid portion (<NUM>) to each other so that the lid portion (<NUM>) is opened when the door (<NUM>) is opened and the lid portion (<NUM>) is closed when the door (<NUM>) is closed; and
a closing timing adjustment unit (<NUM>) that stops a closing motion of the lid portion (<NUM>) in a first stage of a motion of closing the door (<NUM>) and that performs the closing motion of the lid portion (<NUM>) in a second stage of the motion of closing the door (<NUM>) after the first stage,
wherein the link mechanism (<NUM>) includes
a door-side link (<NUM>) swingably connected to the door (<NUM>) so as to be centered on a first end portion (31a) of the door-side link (<NUM>), and
a lid-side link (<NUM>) swingably connected to the lid portion (<NUM>) so as to be centered on a first end portion (32a) of the lid-side link (<NUM>), a second end portion (32b) of which being swingably connected to a second end portion (31b) of the door-side link (<NUM>), and
the closing timing adjustment unit (<NUM>) includes
a slot hole (<NUM>) formed in the second end portion (31b) of the door-side link (<NUM>) so as to extend in a longitudinal direction of the door-side link (<NUM>), and
a slot projection (<NUM>) formed in the second end portion (32b) of the lid-side link (<NUM>), inserted into the slot hole (<NUM>), being movable in a longitudinal direction of the slot hole (<NUM>) in the first stage, and reaching an end (<NUM>) in the longitudinal direction of the slot hole (<NUM>) in the second stage,
characterized in that
the closing timing adjustment unit (<NUM>) further includes
a first projection portion (<NUM>) fixed to the operator cab body (<NUM>), and
a second projection portion (<NUM>) provided in the lid-side link (<NUM>) and pressed against the first projection portion (<NUM>) toward the lid portion (<NUM>) side to restrict a movement of the lid-side link (<NUM>), and,
when the slot projection (<NUM>) reaches the end (<NUM>) in the longitudinal direction of the slot hole (<NUM>), pressing of the second projection portion (<NUM>) against the first projection portion (<NUM>) is released.