JP4592604B2 - Waterproof structure for cross member of carrier frame - Google Patents

Description

  The present invention relates to a cross member that extends in a lateral direction of a vehicle in a cargo bed frame that is disposed between a chassis frame and a cargo bed of a truck to support the cargo bed. It relates to a cross member to be prevented.

  A truck, which is a vehicle for freight transportation, has a chassis frame to which a driver's cab, an engine, wheels, and the like are attached. There are two types of truck beds: open-top and open-type boxes, which are closed-type cargo beds. Recently, the box shape is excellent in terms of preventing cargo slippage and simplifying the packing work of loaded cargo. Carriers are widely used. In a box-type loading platform, a metal plate such as aluminum or a heat insulating panel sandwiching a heat insulating material is used for the side plate and ceiling plate of the loading platform, but wood is often used as the floor plate. Timber floorboards are also frequently used in uncovered cargo beds.

  In a large truck, a carrier frame is mounted on the upper part of the vehicle chassis frame to mount the carrier, and the carrier is placed on this. The loading frame has two subframes (vertical joists) that extend almost the entire length of the loading platform in the front-rear direction of the vehicle, and a number of cross members (horizontal joists) that are fixed to the subframes and extend in the lateral direction of the vehicle. is doing. The sub-frame is fastened to the side rail, which is a frame material extending in the longitudinal direction of the vehicle, in the chassis frame of the vehicle using U-bolts or the like, and the floor plate portion of the cargo bed is fastened to the cross member using tapping screws, bolts, or the like. .

  The cross member of the loading platform frame is a strength member that supports the floor plate of the loading platform and needs to have high strength and rigidity. On the other hand, it is desirable to reduce the weight of the loading platform frame as much as possible in order to improve the fuel economy of the vehicle or increase the cargo load. Since a large number of cross members are arranged on the cargo bed frame, reducing the weight of the cross members exerts a great effect on reducing the weight of the entire cargo bed frame. Under these circumstances, aluminum extruded materials that are lightweight and have excellent formability are often used for the cross members.

  FIG. 4 shows a schematic structure of a conventional truck provided with a loading platform frame, and FIG. 5 shows a cross-sectional view taken along the line AA of FIG. The truck has a chassis frame on which a driver's cab 1, front wheels 2, rear wheels 3 and the like are mounted. The two side rails 4 of the chassis frame extend in the front-rear direction over almost the entire length of the vehicle. On the side rail 4 behind the cab 1, a subframe 5 that also extends in the front-rear direction of the vehicle is mounted and fixed to the side rail 4. A large number of cross members 6 which are orthogonal to the sub frame 5 and extend in the lateral direction of the vehicle are coupled by angle members. The subframe 5 and the cross member 6 constitute a cargo bed frame 7, and a cargo bed 8 represented by a two-dot chain line in FIG. Such a loading frame is disclosed in Japanese Patent Application Laid-Open No. 2005-255077 as an example.

The cross member 6 is a single shape member (long member having a constant cross-sectional shape) made of an aluminum extruded material. As shown in the BB cross-sectional view of FIG. 5, the cross section has an upper side 61, a lower side 62, and a vertical side. It is formed in a U shape having a side 63. In order to couple the loading platform 8 to the cross member 6, a tapping screw 10 that can be tapped with a single screw is screwed from above the wooden floor board 81, and the tapping screw 10 penetrates the upper side 61 of the cross member 6 and 81 is fastened to the cross member 6. Such a fastening method is disclosed in Japanese Patent Application Laid-Open No. 2004-276936 as an example.
An axle cross member 6A having a special structure is disposed above the rear wheel 3 so as to avoid contact between the tire and the cross member due to vertical movement of the rear wheel 3 while the vehicle is traveling. The axle cross member 6A is constructed such that two aluminum extruded members having a U-shaped cross section are stacked one above the other, and only the upper member extends to the upper side of the tire. Even in 6A, a tapping screw is used to fasten the floor plate 81 and the upper profile.
Japanese Patent Laying-Open No. 2005-255077 JP 2004-276936 A

  By the way, even if there is a chassis frame or the like below the loading platform frame, it does not block the ground, so rainwater or the like will splash directly on the loading frame when the vehicle is traveling in the rain. . The splashed water passes through the gap X between the upper surface of the cross member and the floor board (cross section BB in FIG. 5) and reaches the threaded part of the tapping screw due to capillary action or the like. There is a case where it reaches the upper part of the floor plate through a slight gap Y with the threaded portion (male thread) of the screw, which is a phenomenon called so-called water rising. When the water reaches the upper part of the floor board, the cargo loaded on the loading platform may be contaminated or damaged, and the floor board itself may be corroded by the rising water. Conventionally, measures such as applying a sealing material to the upper surface of the cross member or sticking a sealing tape have been taken to prevent water from passing through the gap between the upper surface of the cross member and the floor board and preventing water from rising. It was.

  However, when the floor plate of the cargo bed and the cross member are fastened by the tapping screw, the tip of the tapping screw penetrates the upper side of the cross member and protrudes downward. The water splashed on the protruding portion passes through a very small gap Z between the female thread portion tapped on the upper side of the cross member and the tapping screw and a gap Y of the female thread portion of the floor plate, that is, passes through the upper surface of the cross member. Without being able to reach the top of the floorboard by capillary action.

In the above Patent Document 2, a technique of applying a sealing material to a certain range of the threaded portion of the tapping screw in order to prevent water from entering from the protruding portion of the tapping screw is disclosed. It is necessary to prepare a special sealing material, and when the tapping screw is screwed in, a process of applying the sealing material to a certain range of the screw portion is added, and the work process becomes complicated. In addition, cracks or the like may occur with the secular change of the sealing material or flooring, and there is a possibility that water will rise from here.
An object of the present invention is to improve the structure of the cross member in the cargo bed frame that fastens the floor plate of the cargo bed and the cross member with a tapping screw to realize the above-mentioned problem-free water rise prevention means. It is to improve strength and rigidity.

In view of the above problems, the present invention has a cross member structure in which water splashed during vehicle travel does not cause the tapping screw to collide with a portion passing through the upper side of the cross member and wet this portion. It is to provide. That is, the present invention
“It is a cross member of the carrier frame on which the vehicle carrier is placed,
The cross-section of the cross member has a basic shape of a U-shaped cross-section having a vertical side extending vertically, an upper side and a lower side extending horizontally from the upper end and the lower end thereof, and an opposing portion of the vertical side being opened , The upper side is fastened to the floor plate of the cargo bed by a tapping screw,
A cross-section of the cross member is provided with a connecting side that connects the upper side and the middle part of the vertical side, and a closed space surrounded by the upper side, the vertical side, and the connecting side is formed, and The tapping screw is fastened to the position where the closed space exists. "
It is a cross member characterized by this.

According to a second aspect of the present invention, the connecting side in the cross section of the cross member includes a vertical intermediate side extending downward from the upper side and a horizontal intermediate side extending horizontally from the intermediate side from the vertical side. Is preferred.

  According to a third aspect of the present invention, the tapping screw can penetrate the connection side, that is, the tip can reach the lower side of the connection side through the connection side from the closed space.

The cross member of the present invention basically has a U-shaped cross-sectional shape which is composed of a vertical side and upper and lower sides extending horizontally from the upper end and the lower end of the cross member, and the opposed parts of the vertical side are open. In addition, a connecting side connecting the upper side and the middle part of the vertical side is provided in the cross section , thereby forming a closed space. A tapping screw that fastens the floor of the loading platform and the upper side of the cross member is fastened to a position where this closed space exists. Therefore, there is a connecting side below the portion where the tapping screw passes through the upper side of the cross member, and the portion that passes through the connecting side is covered, so that water does not splash in this passing portion. The water does not rise through the gap between the tapping screw thread and the female thread on the upper side of the cross member.

Moreover, in this invention, the intensity | strength and rigidity of a cross member will increase with the connection edge provided in the cross member. Various loads are applied to the cross member of the loading platform frame due to the weight of the loading platform or acceleration / deceleration during traveling of the vehicle. For example, the weight of the loading platform exerts a bending moment on the cross member that bends both ends in the longitudinal direction of the cross member downward, and as a result, deforms the cross member. In the present invention, the connecting side provided in the cross-sectional shape becomes resistance to deformation, excessive deformation can be prevented, and the strength is improved. When the vertical intermediate side extending downward from the upper side of the cross member and the horizontal intermediate side extending horizontally from the intermediate part of the vertical side are provided as the connecting side as in the invention of claim 2, the respective intermediate sides are so-called. It functions as a reinforcing rib and improves the strength and rigidity of the cross member.

As in the invention of claim 3, when the tapping screw penetrates the connecting side, that is, the tapping screw passes through the closed space and the connecting side, and the tip portion reaches below the connecting side. In this case, as the length of the closed space in the vertical direction is reduced, the length of the entire connection side is also reduced, the amount of material required for the connection side is reduced, the weight of the cross member is reduced, and the cost is also reduced. Further, tapping is also performed on the connecting side, and the tapping screw is supported by being screwed to the cross member at two locations, the upper side and the connecting side. Therefore, the connection between the tapping screw and the cross member is strengthened, and the load acting on the tapping screw is dispersed and supported at two locations. Therefore, the load acting on the coupling portion between the upper side of the cross member and the tapping screw is correspondingly increased. Is alleviated.
In the invention of claim 3, the tip of the tapping screw is exposed below the connecting side, but even if water penetrates through the gap between the female threaded portion of the connecting side and the male threaded portion of the tapping screw, A narrow gap is not continuous upward, and water does not reach the portion where the tapping screw penetrates the upper side of the cross member.

  Hereinafter, the cross member of the present invention will be described with reference to FIGS. 1 to 3. In these drawings, parts corresponding to the conventional cross member of FIGS. 4 and 5 are denoted by the same reference numerals. . Incidentally, the basic structure of the carrier frame to which the cross member of the present invention is applied is the same as that of the conventional one shown in FIGS. A sub-frame 5 extending in the front-rear direction is arranged and fixed on the side rail 4 of the chassis frame. Like the conventional cross member, the cross member 6 of the present invention is a shape member that is arranged above the subframe 5 so as to extend in the lateral direction of the vehicle. The floor plate 81 of the loading platform 8 is fastened by a number of tapping screws 10 arranged at intervals.

FIG. 1 shows a cross-sectional shape of the cross member 6 in the first embodiment of the present invention. The cross-section of the cross member 6 of this embodiment has a vertical side 63 extending vertically, an upper side 61 and a lower side 62 extending horizontally from the upper end and the lower end, and a basic portion in which the opposing part of the vertical side 63 is opened. The connecting side 9 connecting the upper side 61 and the vertical side 63 is a vertical intermediate side 91 extending downward from the upper side 61 and a horizontal intermediate side 92 extending horizontally from the intermediate part of the vertical side 63. And. Therefore, a closed space 93 surrounded by these sides is formed below the upper side 61. Since the cross member 6 is an extruded aluminum material having excellent formability, such a cross-sectional shape can be easily manufactured.

  The tapping screw 10 that fastens the floor plate 81 of the loading platform 8 to the cross member 6 is screwed into the floor plate 81 at a position where the closed space 93 exists, that is, between the vertical side 63 and the vertical intermediate side 91. The tapping screw 10 passes through the floor plate 81 and the upper side 61 while being tapped, and the tip thereof reaches the closed space 93. Since the closed space 93 is shielded from the outside by the connecting side 9 composed of the vertical intermediate side 91 and the horizontal intermediate side 92, the splashed water collides with the portion where the tapping screw 10 penetrates the upper side 61 and this The portion does not get wet, and water does not rise through a slight gap between the female screw portion of the upper side 61 and the male screw portion of the tapping screw 10. In addition, the intrusion of water passing between the upper surface of the cross member 6 and the lower surface of the floor plate 81 can be prevented by applying a sealing material or the like to the upper surface of the cross member 6. It is possible to completely prevent it.

  In the cross member 6 of the first embodiment, a vertical intermediate side 91 and a horizontal intermediate side 92 are provided as the connecting side 9 over the entire length of the cross member 6 in the longitudinal direction. A bending moment load or a torsional moment load is applied to the cross member of the carrier frame 7 due to the weight of the carrier 8 or acceleration / deceleration during traveling of the vehicle. When the load is applied to the cross member, a stress is generated on the connecting side 9 to bear a part of the load. In other words, in the present invention, by providing the connecting member 9 on the cross member 6, the strength and rigidity of the cross member 6 are increased as compared with the conventional one in FIG. In this embodiment, the vertical intermediate side 91 and the horizontal intermediate side 92 exhibit functions equivalent to the reinforcing ribs erected on the upper side 61 of the cross member and the reinforcing ribs erected on the vertical side 63, respectively. .

  FIG. 2 shows a cross member 6 according to a second embodiment of the present invention. In this embodiment, the length of the vertical intermediate side 91 is short, and the tapping screw 10 for fastening the floor plate 81 penetrates the horizontal intermediate side 92 and the tip projects downward. Also in the cross member of the second embodiment, the portion where the tapping screw 10 passes through the upper side 61 is covered by the vertical intermediate side 91 and the horizontal intermediate side 92 which are the connecting sides 9, so that water collides therewith. There is no water leakage from the gap of the threaded portion. The tip of the tapping screw 10 protrudes downward from the horizontal intermediate side 92, but even if water enters through a slight gap between the female screw part formed on the horizontal intermediate side 92 and the male screw part of the tapping screw 10, The narrow gap is not continuous above, and water does not reach the portion where the tapping screw 10 penetrates the upper side 61.

  In the cross member of the second embodiment, since the length of the vertical intermediate side 91 is short, the amount of material required for the connecting side 9 is reduced as compared with that of the first embodiment. As a result, the cross member is reduced in weight. Material costs are also reduced. Furthermore, since the tapping screw 10 is supported by being screw-coupled to the cross member at two locations of the upper side 61 and the horizontal intermediate side 92, the tapping screw 10 and the cross member 6 are firmly joined. The load acting on the tapping screw 10 is distributed and supported at two locations, and the load acting on the joint portion between the upper side 61 of the cross member 6 and the tapping screw 10 is reduced.

  In the cross members of the first and second embodiments described above, a connecting side composed of a vertical intermediate side and a horizontal intermediate side is employed. However, as in the third example of FIG. The upper side 61 and the vertical side 63 may be connected by the side 9. The shape, dimensions, and the like of the connecting side 9 can be appropriately selected in consideration of the load acting on the cross member or the ease of forming the shape member.

  As described above in detail, the present invention provides a closed space in the cross member having a substantially U-shaped cross section by providing a connecting side connecting the upper side and the vertical side of the cross section, and a tapping screw is provided here. The floor plate of the loading platform is fastened to prevent the water from rising to the floor plate. In the above embodiment, a general cross member of an extruded aluminum material is described. However, the present invention is applicable to a cross member made of, for example, a steel plate, or an axle cross member (6A in FIG. 4). Obviously, it can also be applied as an upper profile. Needless to say, the floor plate of the loading platform is not limited to a wooden one, and various modifications such as application to a floor plate made of synthetic resin or aluminum extruded shape are possible.

It is sectional drawing of the cross member in 1st Example of this invention. It is sectional drawing of the cross member in 2nd Example of this invention. It is sectional drawing of the cross member in 3rd Example of this invention. It is the schematic which shows the carrier frame etc. of a truck. It is AA sectional drawing of FIG. 4, and sectional drawing of the conventional cross member.

Explanation of symbols

5 Subframe 6 Cross member 6A Axle cross member 61 Upper side 62 Lower side 63 Vertical side 7 Loading platform frame 8 Loading platform 81 Floor plate 9 Connection side 91 Vertical intermediate side 92 Horizontal intermediate side 10 Tapping screw

Claims (3)

A cross member (6) of a carrier frame (7) on which a vehicle carrier (8) is mounted,
A cross section of the cross member (6) has a vertical side (63) extending vertically and an upper side (61) and a lower side (62) extending horizontally from an upper end and a lower end thereof, and facing the vertical side (63). The upper side (61) is fastened to the floor plate (81) of the cargo bed by a tapping screw (10),
A cross-section of the cross member (6) is provided with a connecting side (9) that connects the upper side (61) and an intermediate part of the vertical side (63) , and the upper side (61) and the vertical side (63). ) And the connecting side (9) are formed, and the tapping screw (10) is fastened to a position where the closed space (93) exists. Cross member. Wherein the connection side in the cross section of the cross member (6) (9), and the upper side (61) extending perpendicularly downward from the vertical intermediate section (91), horizontally extending horizontally from the intermediate portion of the vertical side (63) The cross member according to claim 1, comprising an intermediate side (92). The cross member according to claim 1 or 2, wherein the tapping screw (10) passes through the connecting side (9).

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