JP6114772B2 - Rear bumper for asphalt finisher - Google Patents

Description

  The present invention relates to a rear bumper capable of accommodating an asphalt finisher that can be stored under a rear end portion of a vehicle body frame in a rear bumper of a large-sized truck such as a dump truck.

  As shown in FIG. 3, in the dump truck 2 also used as a cargo truck provided with the rear bumper device 1, the rear bumper 8 of the rear bumper device 1 prevents a phenomenon called submarine in which a passenger car or the like sinks under an accident such as a rear-end collision. Therefore, the height from the ground is strictly limited (within 550mm) according to the safety standards of the Road Transport Vehicle Law, and the length range from the rear end of the loading platform to the inside, that is, the driver's seat side, is also strictly limited (within 600mm to 350mm). Within).

  On the other hand, for example, when the asphalt finisher 7 is used in road pavement work, the rear bumper 8 does not get in the way because the rear bumper 8 gets in the way when the asphalt finisher 7 is pulled down the rear end of the vehicle body frame of the vehicle. A vehicle is provided that is arranged in a retracted position. (See Figure 6)

Specifically, a rear bumper is provided at the rear end portion of the vehicle body frame so as to be pivotable back and forth via an attachment member, and the rear bumper is moved rearward from the rear end portion of the vehicle body frame via the attachment member by an expansion / contraction operation of the expansion / contraction cylinder. It is configured to be arranged at a travel position where it can project by overhanging and a storage position that is rotated forward from this travel position and stored below the rear end of the vehicle body frame (for example, Patent Documents) 1).
Japanese Patent No. 3315514

  3 to 5 are described as the prior art in this patent document 1, and the support arm 4 that supports the rear bumper 8 provided at the rear of the vehicle has its base end turned to the rear end of the cargo bed frame 5. In this method, the hydraulic cylinders 10 are swiveled and housed in a forward and upward manner.

  The hydraulic cylinder 10 in which the distal end of the support arm 4 and the loading frame 5 are coupled by two upper and lower link arms 76 and 77 and the base end is rotatably coupled to the loading frame at an intermediate position between the link arms 76. The tip of the piston rod 101 is coupled.

  When the piston rod 101 contracts from the extended state, the two link arms 76 and 77 are broken as shown by the chain line in FIG. It is stored directly under the carrier frame 5.

  By adopting such a configuration, the rear bumper 8 is swiveled and stored, and one end of the asphalt finisher 7 can be sufficiently drawn below the loading platform frame 5 in the road pavement work. The material can be supplied satisfactorily (FIG. 6).

  However, in such a movable intrusion prevention device, when a rear vehicle collides with the rear bumper 8, the load is directly received by the link arms 76, 77 and the hydraulic cylinder 10, so the hydraulic cylinder 10, the link arms 76, 77, etc. In order to ensure the strength of the steel, the increase in size and weight was inevitable.

  In particular, in order to withstand a large load, the air cylinder mechanism was not useful, and a hydraulic cylinder had to be used. However, the hydraulic power source is limited to some vehicles equipped with cranes and the like, and if this is installed in a general vehicle, it has led to a significant cost increase.

Patent Document 2 below was invented by the inventor as a rear bumper capable of handling an asphalt finisher having a sufficient impact resistance with a simple, lightweight and inexpensive structure.
JP 2010-202160 A

  As shown in FIGS. 7 and 8, reference numeral 8 denotes a rear bumper provided at the rear part of the cargo truck / dump truck 2 having the rear bumper device 1. The rear bumper is supported by the rotary support 9 so as to jump up and move with respect to the load carrier frame 5 at a height and an inner position within the restricted range from the rear end of the load carrier.

  The rotary support body 9 has a vertically long trapezoidal shape that gradually becomes wider from the base end, the vertical side is vertical, the other side is an inclined side, and the rear bumper 8 is fixedly supported at the tip corner. The rear bumper 8 extends in the vehicle width direction at a position below the rear end of the loading platform and is positioned at a predetermined height close to the road surface. The rotation support 9 protrudes from the outer surface of the left and right cargo bed frames 5 and supports the left and right intermediate positions of the rear bumper 8.

  Each of the left and right rotation supports 9 is rotatably supported by inserting a support shaft 11 projecting from the center position of the base end into a bearing member provided on the loading frame 5.

  4 to 6 described as the conventional example, the invention of Patent Document 1 also includes two upper and lower first arms 6a and a second between the rotary support 9 and the loading frame 5 as in the conventional example. The arm 6b is connected by a link arm 6 connected in series, the two arms 6a and 6b are bent, the rotary support 9 is turned to the front upper side of the vehicle, and the rear bumper 8 is stored directly under the frame 5. It is.

  The length of the first arm 6a is larger than that of the second arm 6b (for example, the first arm 6a is 310 mm and the second arm 6b is 125 mm), and the tip of the second arm 6b Is pivotally supported by a triangular bearing pedestal 12 provided on the vertical side of the rotary support 9 with a support shaft 13.

  The upper end of the first arm 6a has a support shaft 14 fitted in a bearing member 15 provided on the loading frame 5 and is supported rotatably.

  In the figure, reference numeral 16 denotes a rotation restricting means by a rotation restricting base for the first arm 6a. The rear bumper 8 is lowered and the link arm 6 is in a straight line position. On the other hand, the rotation is controlled downward (clockwise in the drawing).

  A rod 17a of an air chamber (air cylinder) 17 as a rotation driving means is integrated with a support shaft 14 at the base end of the first arm 6a so that the link arm 6 is refracted toward the rear of the loading frame by rotating upward. It was made to couple | bond with the rotational drive shaft 14a protrudingly provided.

  A rotation protrusion 18 is provided on the rotation drive shaft 14a, and the rod 17a of the air chamber (air cylinder) 17 is pivotally attached to the rotation protrusion 18 so that the support shaft 14 is rotationally driven via the rotation drive shaft 14a. To do.

  In the air chamber (air cylinder) 17, the rear bumper 8 is lowered at the position where the link arm 6 is in a straight line when the rod 17 a is extended. The air chamber (air cylinder) 17 can be operated from the driver's seat.

  Next, the usage will be described. When the rear bumper 8 is used, that is, when the vehicle is running, the air chamber (air cylinder) 17 is in a state where the rod 17a is contracted, the link arm 6 is in a straight line state, and the rear bumper 8 has a height within 550 mm. Set to

  In this state, the rotation restricting means 16 restricts the rotation below the first arm 6a (clockwise in the drawing), and when the rear vehicle collides with the rear bumper 8, as shown in FIG. P can be received directly by the link arm 6 and the rotation restricting means 16. This is because the stopper arm is also used according to the stay angle of the first arm 6 a of the link arm 6.

  Next, in order to move the rear bumper 8 from the travel position to the retracted position, as shown in FIG. 8, the air chamber (air cylinder) 17 extends the rod 17a.

  As a result, the first arm 6a of the link arm 6 rotates counterclockwise in the drawing, the link arm 6 is bent, and as a result, the rotary support 9 is pulled up clockwise in the drawing, and the rear bumper 8 is also Move to the ascending position.

  When the rear bumper 8 is rotated to move from the retracted position to the traveling position, the reverse operation is performed.

  According to the invention of Patent Document 1, when the rod of the air chamber as the rotation driving means is extended, the link arm rotates upward and refracts toward the rear of the cargo bed frame. As a result, the rotating support rotates in a clockwise direction so that the rear bumper at the ground height within the restricted range and at the inner position within the restricted range from the rear end of the loaded platform moves so as to jump up with respect to the loaded frame. To do. As a result, the rear bumper does not get in the way when the asphalt finisher is pulled down below the rear end of the vehicle body frame of the vehicle.

  Since an air chamber (air cylinder) is used in this way and power can be obtained from the vehicle, it is not necessary to provide a hydraulic pressure source as compared with the case of using a hydraulic cylinder, leading to a significant cost reduction.

  In addition, the direction of operation is that the bumper is rotated by lifting the link of the rear bumper, and the operating space is small and compact.

  On the other hand, when the rear bumper collides with the rear bumper when the rear bumper is at the ground level within the restricted range and is located at the inner position within the restricted range from the rear end of the loading platform in normal use, the load is linked. Since it is received directly by the arm and the rotation restricting means, the stopper operating cylinder is not required by using the link arm as a stopper depending on the stay angle of the first arm of the link arm. It is impossible to receive the second arm of the link arm with the rotation restricting cradle. This is because the presence of the rotation restricting cradle hinders the rotation of the rotation support.

  Furthermore, since the rod of the air chamber (air cylinder) is in a contracted state during normal use during running, troubles such as scratches due to stones and freezing trouble can be reduced.

  In Patent Document 1, the air chamber 17 is provided in the length direction of the cargo bed frame 5 with the rod 17a facing sideways.

  The loading platform frame 5 as a whole is susceptible to mud splashing and the air chamber 17 is also at a low position, so that mud etc. are easily covered.

  The strength standard for the rear bumper support is currently 1/2 of GVW (total vehicle weight), but it is expected that the strength standard will become stricter in the future. Accordingly, in order to increase the impact receiving strength when the rear vehicle collides with the rear bumper in the normal use state, the impact is directly received by the link arm and the rotation restricting means, so the rotation restricting means Must be large, and the link arm must be thick and strong. As a result, the air chamber 17 must be large in order to rotate the heavy link arm.

  The object of the present invention is to eliminate the inconvenience of the conventional example, using an air chamber (air cylinder) and taking power from the car, so it is not necessary to provide a hydraulic pressure source compared to the case of using a hydraulic cylinder, With a simple, lightweight and inexpensive structure that leads to significant cost reductions, it has sufficient impact resistance, there is no risk that the air chamber will suffer mud, etc., and it can be made safe with few failures, The purpose is to provide a rear bumper that can accommodate an asphalt finisher that can be compactly accommodated.

  In order to achieve the above object, according to the present invention, a rear bumper is provided at a rear part of a cargo bed frame at a ground height within a restricted range and at an inner position within the restricted range from a rear end of the cargo bed frame. The tip of the link arm, which is supported by the rotary support so as to move up and move with respect to the first arm and the second arm in series, is attached to the rotary support, the rear bumper descends, and the link arm An air chamber serving as a rotation drive means for providing a downward rotation restricting means with respect to the first arm at a position in which the first arm is linear, and refracting the link arm toward the rear of the cargo bed frame by the upward rotation. In a rear bumper of a lorry vehicle in which the rod of the first arm base end is provided with a rotation projection provided with a rotation projection on the first arm, the air chamber lowers the rod. The rotation restricting means is composed of a rotating body that pivotally supports the central portion, and the tip portion on the rear side of the lorry vehicle with respect to the pivot support portion is a hooking surface to the link arm. The gist of the present invention is that the front side portion of the lorry can be engaged with a stopper provided on the cargo bed frame side.

  According to the first aspect of the present invention, when the rod of the air chamber as the rotation driving means is extended, the link arm rotates upward and is refracted toward the rear of the cargo bed frame. As a result, the rotating support rotates in a clockwise direction so that the rear bumper at the ground height within the restricted range and at the inner position within the restricted range from the rear end of the loaded platform moves so as to jump up with respect to the loaded frame. To do. As a result, the rear bumper does not get in the way when the asphalt finisher is pulled down below the rear end of the vehicle body frame of the vehicle.

  Since an air chamber (air cylinder) is used in this way and power can be obtained from the vehicle, it is not necessary to provide a hydraulic pressure source as compared with the case of using a hydraulic cylinder, leading to a significant cost reduction.

  In addition, the direction of operation is that the bumper is rotated by lifting the link of the rear bumper, and the operating space is small and compact.

  Further, since the air chamber is provided at the upper position of the rotary drive shaft with the rod facing downward, the air chamber can be located on the upper side of the cargo bed frame, and can hardly receive mud splashing.

  In addition, the rotation restricting means is constituted by a rotating body that pivotally supports the central portion, so that it is possible to make it unobstructed when it is not necessary to latch.

  According to a second aspect of the present invention, the rotation restricting means includes the first arm of the link arm and the first arm of the link arm at a position where the rear bumper is lowered and the link arm is in a linear state. The gist is that the arm is hooked in the vicinity of the connecting portion of the two arms.

  According to the second aspect of the present invention, when the rear bumper is at the ground level within the restricted range and is located at the inner position within the restricted range from the rear end of the loading platform in the normal use state, the rear bumper is connected to the rear bumper. When the rear-end collision occurs, the load is directly received by the link arm and the rotation restricting means, and is also used as a stopper depending on the stay angle of the first arm of the link arm. By hooking in the vicinity of the connecting portion of the two arms, a large load can be received without making the link arm thick.

The gist of the present invention described in claim 3 is that the rotation restricting means has a restoring spring attached to the front end of the lorry.

According to the third aspect of the present invention, the rotation restricting means is always pulled upward by the restoring spring attached to the front end of the lorry, and surely returns to the horizontal even if there is some snow or mud adhering. Can be.

  As described above, the asphalt finisher-compatible rear bumper of the present invention uses an air chamber (air cylinder) and can take power from the vehicle. Therefore, it is necessary to provide a hydraulic pressure source as compared with the case of using a hydraulic cylinder. In addition, the simple, lightweight, and inexpensive structure that leads to significant cost reductions has sufficient impact resistance, and the air chamber is not subject to mud and can be made safe with few failures. At the same time, the whole can be compactly accommodated.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a side view of a rear bumper capable of handling an asphalt finisher according to an embodiment of the present invention during normal running, and FIG. 2 is a side view of the above-described work.

  7 and 8, reference numeral 8 in the figure denotes a rear bumper provided at the rear of the cargo truck / dump truck 2 equipped with the rear bumper device 1. The rear bumper is supported by the rotary support 9 so that the rear bumper jumps up and moves with respect to the cargo bed frame 5 from the rear edge of the cargo bed to the inside position within the restricted range.

  The rotary support body 9 has a vertically long trapezoidal shape that gradually becomes wider from the base end, the vertical side is vertical, the other side is an inclined side, and the rear bumper 8 is fixedly supported at the tip corner. Further, the rear bumper 8 extends in the vehicle width direction at a position below the rear end of the loading platform and is positioned at a predetermined height close to the road surface. The rotation support 9 protrudes from the outer surface of the left and right cargo bed frames 5 and supports the left and right intermediate positions of the rear bumper 8.

  Each of the left and right rotation supports 9 is rotatably supported by inserting a support shaft 11 projecting from the center position of the base end into a bearing member provided on the loading frame 5.

  The rotary support 9 and the loading frame 5 are connected by a link arm 6 connected in series by two upper and lower first arms 6a and a second arm 6b, and the two arms 6a and 6b are folded. The rotary support 9 is turned to the front upper side of the vehicle, and the rear bumper 8 is stored immediately below the loading frame 5.

  The length of the first arm 6a is larger than that of the second arm 6b (for example, the first arm 6a has a length of 310 mm and a width of 60 mm, and the second arm 6b has a length of 125 mm and a width of 60 mm). The tip of the second arm 6 b is pivotally supported by a triangular bearing base 12 provided on the vertical side of the rotary support 9 with a support shaft 13.

  The upper end of the first arm 6a has a support shaft 14 fitted in a bearing member 15 provided on the loading frame 5 and is supported rotatably.

  In the present invention, an air chamber (air cylinder) 17 is provided at an upper position of the loading frame 5, and a rod 17 a of the air chamber 17 is directed downward so as to project integrally with a support shaft 14 at the base end of the first arm 6 a. The rotary drive shaft 14a was coupled. Although not shown, the air chamber (air cylinder) 17 is supported by a frame above the loading frame 5.

  A rotation protrusion 18 is provided on the rotation drive shaft 14a, and the rod 17a of the air chamber (air cylinder) 17 is pivotally connected to the rotation protrusion 18 so that the rotation protrusion 18 is relatively rotatable. The spindle 14 is rotationally driven through a rotary drive shaft 14a integrated with the rotary shaft 14a.

  In the air chamber (air cylinder) 17, the rear bumper 8 is lowered at a position where the link arm 6 is in a linear state at a position where the rod 17 a extends. The air chamber (air cylinder) 17 can be operated from the driver's seat.

  The rotation regulating means 16 regulates the rotation with respect to the first arm 6a. The rotation regulating means 16 moves downward with respect to the first arm 6a at a position where the rear bumper 8 is lowered and the link arm 6 is in a linear state. The rotation is restricted to (clockwise in the drawing).

  This rotation restricting means 16 is provided on the side of the loading frame 5 with the rotation restricting means 16, but in the vicinity of the connection point between the first arm 6 a and the second arm 6 b of the link arm 6 with respect to the first arm 6 a of the link arm 6. In other words, the first arm 6a and the second arm 6b of the link arm 6 are hooked in the vicinity of the connecting pin 19.

  The rotation restricting means 16 is constituted by a bar-like rotating body 20 that is pivotally supported by a pin 21 at the center, and the inclined surface 22 with the tip portion on the rear side of the lorry as compared to the pivoted portion being a hooking surface for the link arm. Formed. Thus, by making the tip part on the rear side of the lorry into the inclined surface 22, even if the tip part is directed upward, the inclined surface 22 is substantially horizontal, and the first arm 6a of the rotating link arm 6 is rotated. Can be received as is.

  A portion on the front side of the lorry vehicle with respect to the shaft support portion of the rotating body 20 can be engaged with a stopper 23 as a projecting body provided on the loading frame 5 side. When the rotation restricting means 16 is in a horizontal state where it receives the first arm 6 a of the link arm 6, the front portion of the vehicle is engaged with the stopper 23 and fixed.

  The rotating body 20 of the rotation restricting means 16 has a coil spring 24 as a return spring attached to the front end of the lorry, and the other end of the coil spring 24 is connected to the loading frame 5. The coil spring 24 is a contraction spring, and the rotating body 20 is always pulled up to be in a horizontal state and securely engaged with the stopper 23. Thereby, even if there is some snow or mud adhesion, the rotating body 20 can be surely returned to the horizontal.

  As another embodiment, the engagement of the first arm 6a of the link arm 6 and the rotation restricting means 16 can be automated by using the coil spring 24 as an extension spring.

  When the first arm 6a of the link arm 6 is not engaged with the rotation restricting means 16 (see FIG. 2), the coil spring 24 extends so as to jump up the tip of the rotating body 20, and the first arm of the link arm 6 When 6a engages with the rotation restricting means 16, it is pushed and contracted.

  Next, the usage will be described. When the rear bumper 8 is used, that is, when the vehicle is running, the air chamber (air cylinder) 17 is in a state where the rod 17a is extended, the link arm 6 is in a straight state, and the height of the rear bumper 8 is within 550 mm. Set to

  In this state, the rotation restriction cradle 16 restricts the rotation below the first arm 6a (clockwise in the drawing), and when a rear vehicle collides with the rear bumper 8, the load P is applied to the link arm 6 And the rotation restricting means 16 can directly receive them.

  In this case, the rotation restricting means 16 supports the link arm 6 when the rotating body 20 is substantially horizontal. The rotating body 20 is fixed by a stopper 23.

  Next, to move the rear bumper 8 from the travel position to the retracted position, the air chamber (air cylinder) 17 contracts the rod 17a as shown in FIG.

  As a result, the first arm 6a of the link arm 6 rotates counterclockwise in the drawing, the link arm 6 is bent, and as a result, the rotary support 9 is pulled up clockwise in the drawing, and the rear bumper 8 is also Move to the ascending position.

  When the link arm 6 is bent, the rotation restricting means 16 is released from the latch, and as shown in FIG. 2, the tip of the rotating body 20 jumps up and does not get in the way.

  When the rear bumper 8 is rotated to move from the retracted position to the traveling position, the reverse operation is performed.

It is a side view at the time of normal driving | running | working which shows one Embodiment of the rear bumper which can respond to the asphalt finisher of this invention. It is a side view at the time of storage which shows one Embodiment of the rear bumper which can respond to the asphalt finisher of this invention. It is a perspective view of a large lorry. It is a loading platform rear part side view which attached the conventional rush prevention apparatus. FIG. 5 is an enlarged side view of FIG. 4. It is a side view at the time of normal driving | running | working of a prior art example. It is a side view at the time of the normal driving | running | working of the rear bumper which can respond to the conventional asphalt finisher. It is a side view at the time of storage of the rear bumper which can respond to the conventional asphalt finisher. It is explanatory drawing when receiving the impact of the rear bumper which can respond to an asphalt finisher.

DESCRIPTION OF SYMBOLS 1 ... Rear bumper apparatus 2 ... Truck 3 ... Loading platform 4 ... Support arm 5 ... Loading platform frame 6 ... Link arm 6a ... 1st arm 6b ... 2nd arm 7 ... Asphalt finisher 8 ... Rear bumper 9 ... Rotating support body 10 ... Hydraulic cylinder 11 ... support shaft 12 ... bearing base 13 ... support shaft 14 ... support shaft 14a ... rotation drive shaft 15 ... bearing member 16 ... rotation restricting means 17 ... air chamber (air cylinder)
17a ... Rod 18 ... Rotation protrusion 19 ... Connecting pin 20 ... Rotating body 21 ... Pin 22 ... Inclined surface 23 ... Stopper 24 ... Coil spring 76, 77 ... Link arm 101 ... Piston rod

Claims (3)

  The rear bumper is supported with a rotating support so that the rear bumper jumps up and moves with respect to the cargo bed frame at the rear of the cargo bed frame at the ground height within the restricted range and from the rear end of the cargo bed to the inner position within the restricted range. At the position where the tip of the link arm connected in series with the first arm and the second arm is attached to the rotary support, the rear bumper is lowered, and the link arm is linear, A downward rotation restricting means is provided, and an air chamber rod as a rotation driving means is provided with a rotation protrusion at the base end of the first arm so that the link arm is refracted toward the rear of the cargo bed frame by rotating upward. In a rear bumper of a lorry that is rotatably coupled to a rotary drive shaft, the air chamber is provided at a position above the rotary drive shaft with the rod facing downward, and the rotation restriction The stage is composed of a rotating body that pivotally supports the center part, the tip part on the rear side of the lorry from the pivot part is formed on the hooking surface to the link arm, and the front part of the lorry is on the loading platform frame side A rear bumper compatible with asphalt finishers, which can be engaged with the stopper provided.   The rotation restricting means is applied to the first arm of the link arm in the vicinity of the connection point between the first arm and the second arm at the position where the rear bumper is lowered and the link arm is in a straight line state. The rear bumper capable of handling an asphalt finisher according to claim 1. The asphalt finisher-compatible rear bumper according to claim 1 or 2, wherein the rotation restricting means has a restoring spring attached to an end on the front side of the lorry.

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