JPS6251191B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a tail structure for tilting a cab provided in a cab-over type vehicle, and particularly to a torsion rod that functions as a torsion spring for tilting a cab. The effective length of the torsion rod can be extended without being restricted by the layout of the vehicle, sufficient torsion moment and torsion angle can be secured, and the amount of elastic energy stored in the torsion rod, that is, the amount of torsion moment, can be arbitrarily adjusted. This invention relates to a tilt structure that allows the cab to be tilted with an appropriate spring force and improves the support of the cab due to the arrangement of torsion rods and the like.

[Prior Art] As shown in FIG. 1, in a cab-over type vehicle 1, an engine 2 is covered by a cab 3. Therefore, when servicing the engine 2, the cab 3, which has a considerable weight, must be moved outward. In order to make such heavy work easier, the cab-over type vehicle 1 is equipped with a tail structure for pivoting the cab 3 forward.

Conventionally, in this type of tail structure, for example, a single torsion rod or torsion bar 4, which functions as a torsion spring, is provided in the tail center of the front end of the cab 3 in the vehicle width direction. This torsion rod 4 has one end fixed to the cab 3 and the other end fixed to the vehicle body frame 5.
The cab 3 is secured to the body frame 5 by the locking device 6.
When the cab 3 is held in place, it is twisted by its own weight and elastic energy is stored, while the locking device 6
When released, the cab 3 is configured to turn and move forward of the vehicle 1 due to the torsional moment.

[Problems to be Solved by the Invention] By the way, the spring specifications of the torsion rod 4 that are generally adopted in a tail structure take into account the rotational moment due to the weight of the cab 3 and the operating force required when the cab 3 is tilted and locked. It is determined by setting the torsion angle and torque,
Depending on the specifications, the length of the torsion rod 4 may have to be increased. In that case, the torsion rod 4 will protrude a considerable amount in the vehicle width direction,
This may not be possible due to the layout of the steering mechanism and other mechanisms. Also, even if it is possible,
The problem arises of restricting their layout or changing the position of the torsion rods 4.

A related technology is a "truck cab tilt device" that has two torsion bars.
(Utility Model Publication No. 56-141880) and a "pivotal plate balance device" (Utility Model Publication No. 47-26807), which consists of two rods connected in series, have been proposed. By combining these, it is possible to obtain a large twist angle and tilt the cab. However, the "balance device" has a structure in which the rods and hinges are arranged differently, and adopting this device as it is in the limited narrow space between the cab 3 and the vehicle body frame 5 would complicate the structure. It ends up. On the other hand, in the "tilt device", the torsion bar is arranged approximately at the tilt center, which simplifies the structure. By the way, if we pay attention to the arrangement structure of the torsion bar of this "tilt device", one end of one torsion bar is attached to one end of the chassis frame in the vehicle width direction, and the other end is attached to one end of the cab in the vehicle width direction. If this is combined with a structure in which the bars of the "balance device" are folded back and connected in series, one end of a pair of torsion bars folded back to each other is attached to one end of the chassis frame in the vehicle width direction, and the other end is attached to one end of the chassis frame in the vehicle width direction. is attached to one end of the cab in the vehicle width direction.
When the torsion bar is disposed in this manner to support the cab, the cab is supported by being torsioned by the reaction force of the torsion of the torsion bar.
This problem arises because when the torsion bar is placed at the tail center, the cab is directly supported by the torsion bar.

In addition, as a structure for connecting two torsion bars, the "equilibrium device" discloses a folded structure, but this is a structure in which the folded support part moves, and when supporting a heavy object such as a cab. In this case, excessive stress will be generated in this folded part, and it is thought that the structure will lack reliability. The present invention has been devised in view of the problems of the conventional cab tail structure as described above, and to effectively and all at once solve these problems.

An object of the present invention is to substantially extend the length of the torsion rod that functions as a torsion spring for tilting the cab without being restricted by the layout of the vehicle, to ensure sufficient torsional moment and torsional angle, and to provide sufficient torsional moment and angle. The cab's tailing structure is designed to arbitrarily adjust the amount of elastic energy stored in the rod, that is, the amount of torsional moment, to tilt the cab with an appropriate spring force, and to improve the cab's support from the arrangement structure of the torsion rods, etc. Our goal is to provide the following.

[Means for Solving the Problems] The present invention provides a tail structure in which the cab is tilted around the tail center from the vehicle body frame using a torsional moment, and a sleeve that is rotatably provided on the vehicle body frame coaxially with the tail center and supports the cab. a first torsion rod that is inserted coaxially into the sleeve body with the tail center and has one end fixed thereto; and a second torsion rod that is provided parallel to the first torsion rod and has one end fixed to the vehicle body frame. and an arm member provided at each other end of these torsion rods and swinging according to the twisting angle, and the swinging ends of these arm members are connected to each other to maintain a continuous torsion moment, and a separation between these swinging ends is provided. It is configured with a screw body for adjusting the distance.

[Effect] The operation of the present invention will be described.

Two torsion rods are provided in parallel and a torsion moment is continuously applied between these torsion rods via an arm member and a screw body, thereby obtaining a large torsion angle and tilting the cab. Furthermore, when the first torsion rod is disposed at the tail center to make the arrangement more compact and simple, the first torsion rod that is twisted in the axial direction does not directly support the cab. The entire cab is supported through a sleeve body that rotates uniformly, thereby preventing twisting of the cab. Furthermore, when arranging the sleeve body, the first torsion rod is inserted through the tail center to form a double structure, thereby ensuring compactness. In addition, regarding the rotation transmission mechanism between the torsion rods, by adopting an arm member that swings freely according to the torsion angle,
To prevent unnecessary stress from being applied to connecting parts at each end of a torsion rod by converting torsion into a rotational moment. Furthermore, the biasing force of the torsion rod is adjusted by adjusting the spacing using the screw body.

[Embodiment] Next, a preferred embodiment of the cab tail structure according to the present invention will be described in detail with reference to the accompanying drawings.

As shown in FIG. 2, reference numeral 5 denotes a vehicle body frame that forms the frame of the entire vehicle, and a bearing bracket 7 is provided at the front end 5a of the vehicle body frame 5 in the vehicle width direction.
1 and 7r are installed in parallel. First bearing holes 8l and 8r are formed in these bearing brackets 7l and 7r, respectively, and extend through the same axis in the vehicle width direction (in this example, the tail center of the cab). Second bearing holes 9l, 9 are adjacent to and parallel to the holes 8l, 8r.
r is formed through. In this embodiment, as shown in the figure, second bearing holes 9l and 9r are formed below the first bearing holes 8l and 8r.

As shown in FIG. 3, these bearing brackets 7
A tube body 10, which is a sleeve body, is spanned between l and 7r coaxially with the tail center along the vehicle width direction. This tube body 10 consists of a thin-walled steel tube and one end of the tube 10L.
It consists of a thick boss 14l that is welded and fixed inside.
The boss 14l is composed of an outer peripheral surface having approximately the same diameter as the inner diameter of the steel pipe and a through hole (hexagonal hole) having a regular hexagonal cross section, and is formed by drawing. Both ends 10l, 10r of such a tube body 10 are supported by annular rubber bushes 11, 11 provided in the first bearing holes 8l, 8r, and the entire body is mounted between the bearing brackets 7l, 7r. Uniformly rotatably supported. As shown in FIGS. 2 and 3, support brackets 12 are fixed to the tubular body 10 along its longitudinal direction, and these support brackets 12...
A cab is fixed on top. Therefore, the cab is supported by the tubular body 10 and rotated together with the cab with its axis as the tilt center, so that the entire cab is tilted uniformly toward the front of the vehicle. A boss 14r having substantially the same shape as the boss 14l is inserted into the other end 10r of the tubular body 10 so as to be relatively rotatable. The boss 14r is provided with a through hole having a regular hexagonal cross section.

Further, as shown in FIG. 3, inside this tube body 10, a first torsion rod 13 is provided which is inserted coaxially with the tail center along its longitudinal direction, that is, the vehicle width direction, and functions as a torsion spring. . Both end portions of the first torsion rod 13 are each formed to have a regular hexagonal cross section, and are fitted into hexagonal holes of the bosses 14l and 14r, respectively. These bosses 14l and 14r are connected to the first torsion rod 13, respectively.
It is configured to rotate integrally with these at both ends. As mentioned above, among these bosses 14l and 14r, one boss 14l is fixed to the pipe body 10,
The other boss 14r is supported by the tube body 10. Therefore, the first torsion rod 13 has one end connected to the tube body 1.
The other end is configured as an end portion 13l that is fixed at zero, and the other end is an end portion 13r that is rotatable within the tube body 10.

On the other hand, as shown in the figure, the bearing bracket 7l,
7r, a second torsion rod 1 that functions as a torsion spring is installed in parallel with the first torsion rod 13.
5 is crossed. This second torsion rod 1
Both ends of the rod 5 have a regular hexagonal cross section similar to the first torsion rod 13. The second bearing hole 9l has a regular hexagonal cross section, and the other second bearing hole 9r rotatably supports a boss 16 having the same shape as the boss 14r. This second torsion rod 15 has one end connected to the second bearing hole 9.
It is fitted into the hexagonal hole of 1 and fixed to the vehicle body frame 5 via the bearing bracket 7l to prevent its rotation, and the other end is rotatably supported in the other second bearing hole 9r. It is fitted into the hexagonal hole of the boss 16 and is supported as a whole.

As shown in FIGS. 3 and 4, the ends 13r and 15r of the first torsion rod 13 and the second torsion rod 15 are rotatably aligned in bearings 8r and 9r via bosses 14r and 16, respectively. These rods 13 and 15 are provided between the bosses 14r and 16.
A torsion transmitting means 17 is provided which connects the two to transmit the rotation and continuously transmits the torsional moment.
As shown in FIGS. 3 and 4, this torsion transmitting means 17 includes bosses 14 at ends 13r and 15r of the first torsion rod 13 and second torsion rod 15, respectively.
arm members 18 and 19 provided at r and 16 and swinging freely according to the torsion angle, and these arm members 1
It is comprised of a turnbuckle-like screw body 20 that connects the swinging ends 18b, 19b of 8 and 19 to each other to maintain a continuous torsion moment, and adjusts the remote distance between these swinging ends 18b, 19b. The arm members 18, 19 have their respective base ends 18a,
19a is fixed to the bosses 14r and 16, and is configured to rotate integrally with the rotation of the ends 13r and 15r of the first torsion rod 13 and the second torsion rod 15. In addition, these arm members 1
Swing ends 18b and 19b of 8 and 19 extend radially outward from base ends 18a and 19a substantially parallel to each other. A first torsion rod 13 and a second torsion rod 15 are connected in series to these swinging ends 18b and 19b, and their rotation is transmitted to continue the torsion moment applied to them. A screw body 20 for this purpose is pivotally supported. As a result, the first torsion rod 13 and the second torsion rod 15 are configured as one torsion spring as a whole with the fixed ends 13l and 15l as ends, and the torsion rod 13 and the second torsion rod 15 are configured as a single torsion spring as a whole, with the fixed ends 13l and 15l being the end parts. Sufficient torsional moment can be generated without being restricted by layout. The fixed end of this torsion spring as a whole is 15L.
It is. As shown in FIG. 4, the cab 3 is held on the vehicle body frame 5 in a normal running state by a locking device (not shown) on the first torsion rod 13 and the second torsion rod 15 configured in this way. When the cab 3 is being rotated, it is twisted by its own weight and a torsional moment, that is, elastic energy is stored.
On the other hand, when the locking device is released, it is configured to release its elastic energy and swing the cab 3 toward the front of the vehicle.

Further, as shown in the figure, the screw body 20 is adapted to arbitrarily adjust the distance L between the swinging ends 18b and 19b of the arm members 18 and 19. Swing ends 18b, 19b of arm members 18, 19 whose base ends 18a, 19a are fixed to bosses 14r, 16
The first thing is that the separation distance L between the
torsion rod 13 or second torsion rod 15
Alternatively, both of these can be twisted in advance and elastic energy can be stored in them. If this is done, the elastic energy added to these torsion rods 13, 15 in advance will cause
The torsional moment generated by the weight of the cab 3 can be increased or decreased as desired, and the torsional moment can be adjusted by taking into account the operating force when the cab 3 is tilted or locked.

The operation of the above configuration will be described.

As shown in the figure, under normal running conditions, the cab 3 is held on the vehicle body frame 5 by a locking device (not shown). At this time, the cab 3 generates a torsional moment from the first torsion rod 13 to the second torsion rod 15 by the rotational moment due to its own weight, and these torsion rods 13 and 15 are sequentially exposed to elastic energy. is stored. At this time, the first torsion rod 13 and the second torsion rod 15 are constituted by the torsion transmission means 17 as a single torsion spring with an extended axial length that is not restricted by the layout of the vehicle. Sufficient torsion moment and torsion angle can be obtained without increasing the width in the lateral direction.

When tilting the cab 3, release the locking device and the extended torsion rods 13,1
5 releases its elastic energy and causes the cab 3 to turn toward the front of the vehicle due to the torsional moment. Conversely, in order to return the cab 3 to its original position, twist the torsion rods 13 and 15 using the weight of the cab 3 and the rotational moment caused by the operating force, and then twist the torsion rods 13 and 15.
It will be held on top. Note that the torsion rod is normally used to reduce the operating force when the cab is tilted, and the total tilt angle of the cab and the torsion angle of the torsion rod do not match (the torsion angle of the rod is smaller). This is because the operating force is reduced as the cab is tilted.

In the above operation, when adjusting the magnitude of the torsional moment generated in the torsion rods 13 and 15, the separation distance L between the swinging ends 18b and 19b of the arm members 18 and 19 is adjusted using the screw body 20.
It is sufficient to add or reduce elastic energy to the torsion rods 13, 15 in advance. For example, when increasing the torsional moment, the arm members 18, 1
This increases the distance L between the swing ends 18b and 19b of 9. Conversely, in order to reduce the torsional moment, the distance L between the swing ends 18b and 19b is reduced. Therefore, the amount of twisting moment can be arbitrarily adjusted by taking into consideration the operating force when the cab 3 is tilted or locked, the rotational moment of the cab 3, and the like.

In addition, when the first torsion rod 13 is disposed at the tail center to make the arrangement more compact and simple, the cab 3 is supported directly on the first torsion rod 13 which is twisted in the axial direction. By supporting the cab 3 through the tubular body 10 which rotates the whole uniformly,
It is possible to prevent twisting from occurring. Moreover, when the tube body 10 is arranged, compactness can be ensured by inserting the first torsion rod 13 through the tail center to create a double structure. In addition, regarding the transmission mechanism between the torsion rods 13 and 15, by adopting arm members 17 and 18 that swing freely according to the torsion angle, unnecessary stress is applied to the connecting portion of each other end of the torsion rods 13 and 15. I've learned not to participate.

In the above embodiment, the first torsion rod 13
Although the second torsion rod 15 and the second torsion rod 15 are arranged vertically in parallel, the present invention is not limited to this, and the torsion spring as a whole can have one end fixed to the cab 3 via the tube body 10 and the other end fixed to the vehicle body frame 5. It is sufficient that the torsion moment is transmitted to each other by the torsion transmission means 17.

Further, in the above embodiment, the case where two torsion rods 13 and 15 are provided is shown, but it goes without saying that it may be constructed with a large number of torsion rods.

Furthermore, in the above embodiment, the separation distance L between the arm members 18 and 19 is adjusted by the screw body 20, but the arm members 18 and 19 are not able to swing with respect to their base ends 18a and 19a, respectively. Ends 18b, 19
Of course, the lever itself may be constructed of a turnbuckle, for example, so that the length of the lever between b can be adjusted.

It goes without saying that the above-mentioned modified embodiments have the same effects as those of the above-mentioned embodiments, and that they can also be implemented with various modifications without changing the gist.

[Effects of the Invention] (1) As described above, the tail structure for rotating the cab according to the present invention has multiple torsion rods, and the ends of these rods are connected to the arm member and the screw for transmitting the rotation of the rod. By connecting the bodies in series, the effective axial length can be extended sufficiently without being restricted by the layout of the vehicle itself such as vehicle width, the layout of the steering mechanism and other mechanisms, and the same lateral length can be achieved. A larger torsion angle can be obtained compared to one with a large torsion rod.

In addition, since the screw body is configured so that the separation distance between the swinging ends of the arm member can be adjusted, the amount of elastic energy stored in the torsion rod can be arbitrarily and accurately adjusted, and the amount of elastic energy stored in the torsion rod can be adjusted arbitrarily and accurately. You can tail the cab.

Therefore, in addition to increasing the degree of swing in the setting of the spring specifications of the torsion rod, on the vehicle side,
By greatly increasing the degree of freedom in designing the layout and various mechanical parts, it is possible to improve vehicle performance.

(2) In addition, when the first torsion rod is arranged at the tail center to make the arrangement more compact and simple, the cab is directly supported by the first torsion rod which is twisted in the axial direction. Since the cab is supported via a sleeve body that rotates the entire cab uniformly, twisting of the cab can be prevented. Furthermore, when arranging the sleeve body, compactness can be ensured by inserting the first torsion rod through the tail center to create a double structure.

(3) Regarding the transmission mechanism between the torsion rods,
By adopting an arm member that swings freely according to the torsional angle, there is no movement of the fulcrum, and by converting torsion into rotational moment and transmitting it, there is no unnecessary stress on the connecting part of each other end of the torsion rod. can be prevented from being added.

[Brief explanation of the drawing]

FIG. 1 is a schematic side view showing the tailing condition of a general cab; FIG. 2 is an exploded perspective view showing a preferred embodiment of the cab tailing structure according to the present invention; FIG. 3 is a front sectional view thereof; The figure is in Figure 3 -
It is a line arrow view. In the figure, 3 is a cab, 5 is a body frame, 10 is a tube body which is a sleeve body, 13 is a first torsion rod,
15 is a second torsion rod, 18 and 19 are arm members, and 20 is a screw body.

Claims (1)

[Claims] 1. In a tail structure in which the cab is tilted around the tail center from the vehicle body frame using a torsional moment, a sleeve body is rotatably provided on the vehicle body frame coaxially with the tail center and supports the cab, and the tail center is disposed within the sleeve body. a first torsion rod coaxially inserted through the torsion rod and having one end fixed thereto; a second torsion rod provided parallel to the first torsion rod and having one end fixed to the vehicle body frame; An arm member provided at each other end and swinging according to the torsion angle, and the swinging ends of these arm members are connected to each other to maintain a continuous torsion moment and to adjust the separation distance between these swinging ends. The tail structure of the cab is characterized by having a screw body.