JPH0139201Y2 - - Google Patents

Description

[Detailed explanation of the idea] [Industrial application field]

The present invention relates to a traction connection structure, and more particularly to a traction connection structure incorporating means for simply and accurately detecting the hitch load that has the greatest effect on running stability during towing.

[Prior art]

When towing is performed using a towing connection structure that includes a hitch member that is attached to the towed vehicle and whose tip is removably fitted into the hitch ball on the towed vehicle and connected in three axes, the hitch load ( The load on the hitch member (on the hitch ball) greatly affects running stability during towing. When the hitch load is small, the towed vehicle causes a so-called sway phenomenon around the hitch ball (hitch point) due to unevenness of the road surface or crosswind while driving, which impairs the stability of the towed vehicle. On the other hand, if it is too large, the running performance of the towing vehicle will change significantly, causing problems such as the inability to smoothly turn curves. Normally, this hitch load is maintained at an appropriate value mainly by changing the way the cargo is loaded.
The amount of hit load occurring at that point during loading has been estimated by humans based on experience from the loading conditions. However, this method has a problem in that individual errors greatly affect the estimation of hitch loads. That is, in some cases, the driver may have to drive once to check the state of sway vibration, and if the sway vibration is large, he may have to stop again and adjust the stacking method.

[Purpose of invention]

The present invention has been developed in view of the above-mentioned conventional problems, and is capable of accurately detecting the current hitch load when loading cargo onto a towed vehicle with a simple configuration. To provide a towing connection part structure that allows cargo to be loaded while constantly checking the hitch load that has the greatest influence on running stability during towing.

[Structure of the idea]

The present invention provides a traction connection structure including a hitch member that is attached to the towed vehicle and whose tip is removably fitted into a hitch ball on the towed vehicle and connected in three axial directions. The hitch member side receiving part to be pressed is connected to the hitch ball through an elastic member that can be expanded and contracted according to the pressure contact force so as to be relatively displaceable in the vertical direction, and the receiving part on the hitch member side is attached to either the hitch ball side or the hitch member side in the vertical direction. The above object has been achieved by providing a scale along the entire length and providing an indicating mark on the other side for reading the vertical relative displacement using the scale.

[Effect of invention]

In the present invention, the hitch member side receiving part, which is pressed against the upper part of the hitch ball by the hitch load, is connected to the hitch ball so as to be relatively displaceable in the vertical direction via an elastic member that can expand and contract according to the pressing force. Further, a scale is provided on either the hitch ball side or the hitch member side in the vertical direction. In addition, since the other side is configured to have an indicating mark for reading the relative positional displacement in the vertical direction using the scale,
The hit load can be directly observed visually based on the relative displacement of the hit member side receiving portion which moves up and down due to the expansion and contraction of the elastic member.

【Example】

Embodiments of the present invention will be described in detail below based on the drawings. As shown in FIGS. 1 to 3, this embodiment is attached to the towed vehicle 10 side, and the tip portion 12 is removably fitted into a hitch ball 16 on the towed vehicle (not shown) side. In the traction connection structure including hitch members 18 connected in the axial direction, a hitch member side first receiving part 20 that is pressed against the upper part of the hitch ball 16 is supported so as to be displaceable in the vertical direction X via an elastic member 22. In addition, a display means 24 is provided for displaying the hit load based on the displacement of the hit member side first receiving portion 20. The hitch member 18 has a box shape with an open bottom as a whole, and the hitch member side first receiving part 20 is located at the top of the hitch ball 16 at the tip thereof, and is located at the front and left and right bottom of the hitch ball 16. Curved hitch member side 2nd
The hitch ball 16 is restrained in the three axial directions of front and back, up and down, and left and right by the receiving part 30 and the hit member side third receiving part 32 of the attachment/detachment attachment 28 located at the rear lower part of the hitch ball 16. The hit member side first receiving part 20 has a concave spherical surface 34 along the outer shape of the hit ball 16 on the lower side, and receives the hit member 1 through the elastic member 22 on the upper part.
It is supported on the inner upper surface of 8 so as to be movable in the vertical direction X. The elastic member 22 is a coil spring, and connects the upper part of the hitch ball 16 and the inner upper back side of the hitch member 18 via a fixing metal fitting 36. The display means 24 includes an instruction arrow (instruction mark) 54 drawn on the front elevational surface 52 of the first receiving portion 20 on the hit member side, and a front end surface of the hit member in order to make this instruction arrow 54 visible. a window 56 opened in the upper part of the second receiving part 30, and a scale that allows the vertical movement state of the instruction arrow 54 drawn on the side of the window 56 and visually recognized from the window 56 to be visually observed. It consists of 58. The hit member side second receiving portion 30 includes a concave spherical surface 30A that extends along the front part and a portion of the left and right sides of the lower spherical surface of the hit ball 16. The detachment attachment 28 includes the hit member side third receiving portion 32 at the front end, and
an arm 31 whose rear end is supported by a hinge 46 so as to be swingable in the vertical plane;
A bolt 48 suspended via the hinge 33 is screwed into the upper surface of the hitch member, and the height of the bolt 48 is changed depending on the amount of screwing, and the hanging angle of the arm 31 is adjusted to θ. It is comprised of a nut 50 for adjustment and removal. The third receiving portion 32 on the hit member side has a concave spherical surface 40 along the hit ball 16 on the lower side of its tip surface.
A vertical upright portion 44 is provided on the upper side of the distal end surface. This hit member side third receiving portion 32 is adapted to engage with the front and left and right lower portions of the hit ball 16 when the nut 50 for removal and removal is tightened. Furthermore, hitchi ball 1 of hitchi member 18
Attachment/removal to/from the third receiving portion 32 is performed by rotating the third receiving portion 32. Reference numeral 60 in FIG. 1 indicates a wheel on the towed vehicle side, and 62 indicates its axle. The operation of this embodiment will be explained below. The hitch member 18 is attached to the hitch ball 16 using bolts 48 and nuts 50.
This is done by the rotation of the When no cargo is loaded on the towed vehicle 10, only a so-called free balance load is applied to the upper part of the hitch ball 16 via the hitch member side first receiving part 20, and the elastic member 22 is in a slightly compressed state. . As a result, the pointing arrow 54 drawn on the front elevational surface 52 of the first receiving part 20 is displaced slightly upwardly with respect to the hitch member 18 and moved to approximately the center of the window part 56.
If the maximum load on the side is 500 to 1000 kg・f, the scale is 58.
It refers to around 60Kg・f. This is in good condition. When the towed vehicle 10 starts to be loaded with cargo, a new rotational moment is applied to the towed vehicle 10 depending on the weight of the cargo and the distance from the axle 62 in the longitudinal direction.
The pressing force applied to the upper part of the hitch ball by the first receiving part 20, that is, the hitch load changes. This change is reflected in the expansion and contraction of the elastic member 22, and since the first receiving part 20 moves up and down relative to the hit member 18, the pointing arrow 54 drawn on the front elevational surface 52 of the first receiving part 20 moves up and down within the window portion 56. Therefore, by reading the corresponding scale 58, the increase or decrease in the hitch load can be directly observed. As a result, for example, when the hit load is decreasing, heavy loads are moved to the front side of the axle 62 and loaded, so that loading can always be carried out with the optimal hit load. Although the elastic member 22 is a coil spring in the above embodiment, it may be of any type as long as it expands and contracts according to the hit load.
For example, as shown in FIG. 3, this may be replaced with a soft synthetic resin member 22A such as rubber. Further, the display means 24 is not limited to the configuration of the above embodiment, and for example, a scale may be drawn on the first receiving portion 20 side on the hit member side, and an indicating arrow may be drawn on the side of the window portion 56. Further, in the above embodiment, the window portion 56 is formed in the front elevational surface 52 of the hit member, but it may be formed in the front side surface. Furthermore,
When a coil spring is used as the elastic member 22, an opening is formed on the upper surface of the hitch member corresponding to the center of the upper part of the elastic member 22, and a scale erected above the first receiving portion 20 is inserted through the opening. The scale may be made to protrude, and the hit load may be displayed by the amount of protrusion of the scale from the top surface of the hit member.

[Effect of the idea]

Since the present invention has the above-described configuration, when loading a towed vehicle, it is possible to always check the current load of the hitch, which has the greatest effect on driving stability during towing. You can get excellent results. As a result, even a person with little experience in cargo handling can handle cargo with an appropriate hit load, thereby preventing the need to reload cargo due to the occurrence of sway vibrations after driving. be able to. Furthermore, since the elastic member is interposed between the hitch ball and the hitch member, the effect of vertical positional deviation between the towing vehicle and the towed vehicle can be absorbed without impact.

[Brief explanation of the drawing]

Fig. 1 is a perspective view of a towed vehicle to which the towing connection structure according to the present invention is applied, and Fig. 2 is a -
FIG. 3 is an enlarged sectional view taken along the line, FIG. 3 is a - line view of FIG. 2, and FIG. 4 is a sectional view corresponding to FIG. 2 showing another embodiment of the present invention. 10...Towed vehicle, 12...Tip, 14...
Traction vehicle, 16... hitch ball, 18... hitch member, 20... (hitch member side) first receiving part, 22... elastic member, 24... display means, X...
…vertical direction.

Claims (1)

[Scope of Claim for Utility Model Registration] In a towing connection structure comprising a hitch member that is attached to the towed vehicle side and whose tip part is removably fitted into a hitch ball on the towed vehicle side and connected in three axial directions, A hitch member side receiving part that is pressed against the upper part of the hitch ball is connected to the hitch ball so as to be relatively displaceable in the vertical direction via an elastic member that can be expanded and contracted according to the pressure contact force, and is attached to either the hitch ball side or the hitch member side. A traction connection structure, characterized in that a scale is attached to the vertical direction thereof, and an indication mark is provided on the other side for reading the relative displacement in the vertical direction by the scale.