CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority to Japanese Patent Application No. 2020-162271 filed Sep. 28, 2020, the disclosure of which is hereby incorporated by reference in its entirety.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a work vehicle including an attachment device for attaching an engine auxiliary machine to an auxiliary machine fixing portion formed integrally with (or inseparably from) a engine section.

2. Description of the Related Art

An example of a work vehicle of the above-noted type is known from Japanese Unexamined Patent Application No. 2020-51424 document. In this work vehicle according to the conventional art, at a position upwardly of a engine section disposed inside an engine room, an exhaust gas treatment device as an engine auxiliary machine is supported via an attachment device. The attachment device is configured to bolt-couple a support table member to the auxiliary machine fixing portion formed integrally with the engine section. When the support table member is to be bolt-coupled to the auxiliary machine fixing portion formed integrally with the engine section, firstly, a coupling bolt will be threaded and temporarily fastened with a nut which is disposed on the side opposite the support table member across the auxiliary machine fixing portion. And, this temporary fastening operation is effected by a manual operation using a manual operation tool for example. Under this temporarily fastened state, a separate operation will be effected in such a manner as effecting attachment of the exhaust gas treatment device mounted to the attachment device while adjusting a connection state of an exhaust manifold or an exhaust pipe etc. to be connected subsequently. Thereafter, a final fastening operation of the coupling bolt is effected with using a power tool such as an impact driver. In this, if e.g. the temporarily fastened state is too loose because the temporary fastening operation has not been done properly or has hardly been done, the fastening operation per use using the power tool may not be possible due to idle rotation (or racing) of the nut. Conversely, if the temporary fastening has been done too tightly, there may occur an error or distortion of bonded position at a connecting position between the exhaust gas treatment device and a machine disposed before/after it or connection failure which invites e.g. deformation of a gasket. In this respect, there remains room for improvement. The present invention provides a work vehicle that allows easy checking of whether a preliminary temporary fastening operation has been done properly or not when a support table member of an attachment device is to be bolt-coupled at the time of attachment of an engine auxiliary machine to the auxiliary machine fixing portion.

SUMMARY OF THE INVENTION

As a solution proposed for accomplishing the above-noted object, a work vehicle according to the present invention comprises:

an auxiliary machine fixing portion formed integrally with an engine section and capable of attaching an engine auxiliary machine;

an attachment device for attaching the engine auxiliary machine to the auxiliary machine fixing portion;

a support table member included in the attachment device and configured to attach the engine auxiliary machine to the auxiliary machine fixing portion under a predetermined posture;

a coupling mechanism included in the attachment device and configured to fixedly couple the support table member to the auxiliary machine fixing portion;

a coupling bolt included in the coupling mechanism and provided to extend through the support table member and the auxiliary machine fixing portion; and

an abutment member included in the coupling mechanism to come into abutment against the auxiliary machine fixing portion on the side oppose the side abutted by the support table member across the auxiliary machine fixing portion, the abutment member having a nut portion threaded to the coupling bolt;

wherein in the abutment member, there is formed a locking protrusion protruding to the side where the auxiliary machine fixing portion is present as the target of abutment;

wherein in the auxiliary machine fixing portion, there are formed an insertion hole for the coupling bolt and an anti-rotation hole in which the locking protrusion can be fitted;

wherein the locking protrusion has its protrusion amount in the protruding direction set such that the locking protrusion is fitted in the anti-rotation hole between a state where the abutment member is at its maximally fastened position in abutment against the auxiliary machine fixing portion and a state where the abutment member is at a temporarily fastened position set to a loosening side by a predetermined amount from the maximally fastened state; and

wherein the locking protrusion has the protrusion amount in the protruding direction set such that the locking protrusion is located at a position withdrawn from the anti-rotation hole when the abutment member is located at a position farther from the auxiliary machine fixing portion than the temporarily fastened position.

With the present invention, the coupling mechanism of the attachment device includes, on the side opposite the side abutted by the support table member across the auxiliary machine fixing portion, an abutment member having a nut portion threaded to the coupling bolt. In this abutment member, there is formed a locking protrusion protruding toward the side where the auxiliary machine fixing portion as the target of abutment is present. And, in the auxiliary machine fixing portion, there is formed an anti-rotation hole in which the locking protrusion can be fitted. And, the locking protrusion has its protrusion amount in the protruding direction set such that the locking protrusion is fitted in the anti-rotation hole between a state where the abutment member is at its maximally fastened position in abutment against the auxiliary machine fixing portion and a state where the abutment is at a temporarily fastened position set to a loosening side by a predetermined amount from the maximally fastened position. And, the protrusion amount in the protruding direction is set such that the locking protrusion is located at a position withdrawn from the anti-rotation hole when the abutment member is located at a position farther from the auxiliary machine fixing portion than the temporarily fastened position. Therefore, it is readily possible to check whether an appropriate temporary fastening operation has been effected or not when conducting a temporary fastening operation by threading the coupling bolt to the nut portion of the abutment member located at a position where visual confirmation is difficult. It is also readily possible to check whether the temporary fastening operation has been effected appropriately or not when a final fastening operation is to be effected. Namely, at the time of effecting a temporary fastening operation, for checking whether the temporary fastening is appropriate or not, while the temporary fastening operation of the coupling bolt is being effected with pressing a manual tool for manual operation against the head portion of the coupling bolt, the abutment member located on the side opposite the auxiliary machine fixing portion will be moved slightly in the direction perpendicular to the axis of the coupling bolt, whereby it is possible to check whether the locking protrusion has been fitted into the anti-rotation hole or not. If fitting of the locking protrusion into the anti-rotation hole has been confirmed, with this, it may be determined that the temporary fastening operation has been effected as intended. Or, also when the final fastening operation is to be effected, it is readily possible to check whether the temporary fastening operation has been effected appropriately or not. Namely, prior to execution of the final fastening operation, it is readily possible to check problems such that adjustment is found difficult due to occurrence of some error or distortion in the coupling position at the connection portions between the engine auxiliary machine and any component disposed therebefore or thereafter, there is found some connection failure inviting deformation of the gasket due to too tight temporary fastening, etc. Further, when a fastening operation by a power tool placed against the head portion of the coupling bolt is attempted when a final fastening operation is to be effected, if racing or idle rotation of the nut occurs to disable the fastening operation per se by the power tool, it may be determined that the temporary fastening operation has been effected too loosely or no temporary fastening operation has been effected at all. In this way, when a temporary fastening operation is effected or a final fastening operation is effected, it is possible to check whether the temporary fastening operation has been effected appropriately or not. Consequently, there is achieved an advantage that the possibility of occurrence of assembly error in a finished product can be minimized.

Preferably, the work vehicle having the above-described configuration further comprises:

a knob portion that can be gripped during an attachment operation, the knob portion being included in the abutment member and extended in a direction intersecting a line segment interconnecting the nut portion and the locking protrusion and to a direction away from the auxiliary machine fixing portion.

With the above-described arrangement, in the abutment member, there is provided a knob portion that can be gripped during an attachment operation, the knob portion being extended to a direction away from the auxiliary machine fixing portion. Therefore, at the time of temporary fastening, when the coupling bolt is to be fastened with pressing a manual tool for a manual operation against the head portion of the coupling bolt, it is readily possible to grip the abutment member located on the side opposite the auxiliary machine fixing portion. Thus, it is readily possible to effect e.g. a confirming operation to confirm whether the locking protrusion has been fitted into the anti-rotation hole or not. More particularly, when a temporary fastening operation of the coupling bolt is effected with pressing the manual tool against the head portion of the coupling bolt, the abutment member located on the side opposite to the auxiliary machine fixing portion which is located at a position where access by hand is difficult can be gripped relatively easily by gripping the knob portion extended in the direction away from the auxiliary machine fixing portion, whereby the temporary fastening operation of the coupling bolt can be carried out with stabilizing the posture of the abutment member by gripping of the knob portion. Therefore, in the course of the temporary fastening operation, when one tries to slightly pivot the knob portion about the axis of the coupling bolt, if the knob portion pivots without much resistance, this means that the fastened state is too loose with the locking protrusion being not yet fitted into the anti-rotation hole. Conversely, if the knob portion will not pivot at all even when one tries to pivot the knob portion by gripping it, this means that the fastened state is too tight. And, if the locking protrusion will slightly move loosely or slightly rattle within the anti-rotation hole, one can confirm this as indication of the temporary fastening being effected appropriately.

Preferably, in the work vehicle having the above-described configuration,

the nut portion is provided at one side end portion of the abutment member; and

the knob portion is provided at the other side end portion opposite to the side where the nut portion is provided.

With the above-described arrangement, at the time of temporary fastening operation, when the coupling bolt is to be fastened with pressing the manual tool for manual operation against the head portion of the coupling bolt, the knob portion may be pivotally operated about the nut portion side with gripping of the knob portion provided at the end portion opposite to the side where the nut portion is provided, whereby the confirming operation of the fit-in state of the locking protrusion in the anti-rotation hole can be carried out easily.

Preferably, in the work vehicle having the above-described configuration:

the locking protrusion is provided between the portion where the nut portion is provided and the portion where the knob portion is provided, the locking protrusion being closer to the knob portion.

With the above-described arrangement, since the locking protrusion is provided between the portion where the nut portion is provided and the portion where the knob portion is provided and closer to the knob portion, it is readily possible to sensorily recognize the relative position of the locking protrusion relative to the knob portion. Thus, confirming operation of the fitting-in state of the locking protrusion to the anti-rotation hole can be carried out even more easily.

Preferably, in the work vehicle having the above-described configuration:

of the knob portion, the end portion thereof away from the auxiliary machine fixing portion is tilted toward the side opposite to the protruding direction of the locking protrusion.

With the above-described arrangement, since the end portion of the knob portion is tilted toward the side opposite to the protruding direction of the locking protrusion, the knob portion can be gripped easily as it is located at a position as far as possible from the auxiliary machine fixing portion where various kinds of members are present.

