Utility vehicle

1. A utility vehicle comprising:

a vehicle body frame;

a seat frame including a seat bottom support member and a seat backrest support member, at least the seat bottom support member and the seat backrest support member being formed by square pipes with rectangular cross-sections;

a seat bottom fastened to the seat bottom support member; and

a seat backrest fastened to the seat backrest support member;

wherein the seat bottom support member and the seat backrest support member of the seat frame are integral with each other to have a bent portion;

the seat bottom support member of the seat frame is fastened to the vehicle body frame;

the seat backrest has a convex portion and a recess on a back surface thereof; and

the seat backrest support member is fastened to the seat backrest in contact with a back surface of the seat backrest and is disposed forward relative to a rear surface of the convex portion.

2. The utility vehicle according to claim 1 ,

wherein the seat bottom support member of the seat frame is fastened to the vehicle body frame in such a manner that the seat bottom support member is in surface contact with the vehicle body frame.

3. A utility vehicle comprising:

a vehicle body frame;

a seat frame including a seat bottom support member and a seat backrest support member, at least the seat bottom support member and the seat backrest support member being formed by square pipes with rectangular cross-sections;

a seat bottom fastened to the seat bottom support member; and

a seat backrest fastened to the seat backrest support member;

wherein the seat bottom support member and the seat backrest support member of the seat frame are integral with each other to have a bent portion;

the seat bottom support member of the seat frame is fastened to the vehicle body frame; and

each of the seat bottom and the seat backrest has an opposite surface opposite to the seat frame in a rightward and leftward direction.

4. A utility vehicle comprising:

a vehicle body frame;

a seat frame including a seat bottom support member and a seat backrest support member, at least the seat bottom support member and the seat backrest support member being formed by square pipes with rectangular cross-sections;

a seat bottom fastened to the seat bottom support member; and

a seat backrest fastened to the seat backrest support member;

wherein the seat bottom support member and the seat backrest support member of the seat frame are integral with each other to have a bent portion;

the seat bottom support member of the seat frame is fastened to the vehicle body frame; and

the seat bottom is provided with a rubber-made damper on a portion of a lower surface of the seat bottom which is opposite to an upper surface of the seat bottom support member.

5. The utility vehicle according to claim 1 ,

wherein the seat frame having the bent portion has a configuration in which a square pipe of a straight-line shape is bent at a portion of the square pipe which is provided with a portion formed by cutting, in a direction toward the portion formed by cutting, and the portion formed by cutting is welded.

6. The utility vehicle according to claim 1 ,

wherein at the bent portion or in a vicinity of the bent portion of the seat frame, a seat belt accommodating portion is fastened to the seat bottom support member and the seat backrest support member.

7. A utility vehicle comprising:

a vehicle body frame;

a seat frame including a seat bottom support member and a seat backrest support member, at least the seat bottom support member and the seat backrest support member being formed by square pipes with rectangular cross-sections;

a seat bottom fastened to the seat bottom support member; and

a seat backrest fastened to the seat backrest support member;

wherein the seat bottom support member and the seat backrest support member of the seat frame are integral with each other to have a bent portion;

the seat bottom support member of the seat frame is fastened to the vehicle body frame;

the seat frame includes a first fastening portion;

the vehicle body frame includes a second fastening portion opposite to the first fastening portion;

one of the first fastening portion and the second fastening portion has a plurality of first mounting holes arranged in a forward and rearward direction;

the other of the first fastening portion and the second fastening portion has a second mounting hole corresponding to one of the plurality of first mounting holes; and

the first fastening portion is fastened to the second fastening portion by a fastener member inserted into one of the plurality of first mounting holes and into the second mounting hole.

8. A utility vehicle comprising:

a vehicle body frame;

a seat frame including a seat bottom support member and a seat backrest support member, at least the seat bottom support member and the seat backrest support member being formed by square pipes with rectangular cross-sections;

a seat bottom fastened to the seat bottom support member; and

a seat backrest fastened to the seat backrest support member;

wherein the seat bottom support member and the seat backrest support member of the seat frame are integral with each other to have a bent portion;

the seat bottom support member of the seat frame is fastened to the vehicle body frame; and

the seat backrest has, on a front surface thereof, a swelling portion extending along a backbone of a passenger.

9. The utility vehicle according to claim 1 , comprising:

a plurality of seats arranged at least either front and rear sides or at right and left sides; the seats being provided separately; and

each of the plurality of seats includes the seat frame, the seat bottom and the seat backrest.