JPS6329675B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a cab suspension device for a cab-over-engine vehicle, and more specifically, to accurately prevent wobbling of a floating bar that detachably supports the lower rear end of the cab. The present invention relates to a suspension device that is capable of suppressing rebound of a floating bar (cab).

A floating bar that supports the rear end of the cab is elastically supported by a rear arch fixed to the chassis frame using coil springs, etc., thereby increasing the vibration isolation performance between the chassis frame and the cab. In some cases, the floating bar is used as a foothold for workers when inspecting and repairing an engine or the like by tilting the cab.

However, in the past, there was no mechanism to restrict the free movement of the floating bar, so
When a floating bar is used as a scaffold as described above, the floating bar may wobble due to the shift of the worker's weight (a pitching motion in which the floating bar tilts back and forth while maintaining almost the same height). (The same applies hereafter), which resulted in the problem of being forced to perform unstable work.

For example, as in the cab suspension device disclosed in Japanese Utility Model Application Publication No. 54-50324, a floating bar is attached to the bridge (rear arch) fixed to the chassis frame using shear type anti-vibration rubber. In this case, although the floating bar does not wobble, the vibration isolation performance between the chassis frame and the cab deteriorates, and the riding comfort of the cab cannot be sufficiently improved.

The present invention has been made to solve these conventional problems, and provides a floating bar that supports the rear end of the cab without reducing the vibration isolation function between the chassis frame and the cab. To provide a suspension device for a cab which can be used as a stable footing during work and can also effectively suppress rebound of the cab when traveling on rough roads.

In order to achieve such an object, in the present invention, a cab is supported on a frame on the chassis side by a suspension device, and a pair of left and right brackets are fixed to the rear arch fixed to the frame. A floating bar that detachably supports the lower rear end of the cab is mounted on the bracket so as to be movable up and down through a pair of left and right springs. Further, the floating bar is configured with a member that opens downward, and the floating bar has a closed cross-section portion that is closed in the vertical direction and has a width in the front-back direction that is approximately the same width as the width in the front-back direction of the floating bar. It is formed near both the left and right ends of. A stopper member having a width substantially the same as the front-rear width of the floating bar is fixed to a portion integral with the rear arch, so that the stopper member faces inside the closed section, and a lower part of the rear end of the cab is fixed to the rear arch. When the cab is supported on the floating bar, the stopper member is positioned approximately at the vertical center of the closed section, while when the cab is tilted, the floating bar is pressed upward and the stopper member The member that closes the opening of the floating bar is pressed and held with a front-back width that is approximately the same as the front-back width of the floating bar, and the spring is strong enough to prevent the floating bar from wobbling. It is characterized by being composed of

Therefore, in a normal state where the lower rear end of the cab is placed on the floating bar, the weight of the cab compresses the pair of left and right springs and lowers the floating bar, thereby lowering the stopper. Since the member is located approximately at the vertical center of the closed section, the floating bar is allowed to move up and down.

However, when the load applied to the floating bar decreases as the cab tilts, the floating bar is pushed up by the restoring force of the pair of left and right springs. The members fixed near both ends of the bar have a considerably wide width in the front and back direction of the stopper member (almost the same width as the width in the front and back direction of the floating bar).
It is held under pressure.

For this reason, even if a worker who is sufficiently lightweight compared to the cab rides on the floating bar, the pair of left and right springs will not be compressed, and the free movement of the floating bar will be prevented. Then,
Even when inspecting and servicing the engine using the floating bar as a foothold, the floating bar does not wobble due to the shift of the worker's weight, and work safety is ensured.

Embodiments of the present invention will be described in detail below based on the drawings.

In FIGS. 1 and 2, a cab 1 is mounted on a frame 2 on the chassis side via a suspension device 3, and a rear arch 4 fixed to the frame 2 has a rear arch 4 near the upper end on both left and right sides facing outward. Fix the bracket 5, and
Floating bar 8 via coil spring 6 on top
The lower rear end 1a of the cab 1 is removably mounted on the floating bar 8. 7 is the left and right coil spring 6
This is a shock absorber that connects the bracket 5 and the floating bar 8 at the center thereof, and damps the vibrations of the floating bar 8.

Here, the floating bar 8 is constituted by a channel member having a U-shaped cross section that opens downward, and a contact member 9 that opens upward and has a U-shaped cross section is fixed to the lower part of both left and right ends 8a. A closed cross-section portion 8b having a width in the front-rear direction that is approximately the same as the width in the front-rear direction of the floating bar 8 is formed. Then, the upper ends of the stopper members 10 whose lower ends 10c are fixed to the bracket 5 are bent toward the center of the vehicle body so that the bent ends 10a face inside the closed section 8b, and the bent ends 10c are fixed to the bracket 5. An elastic member 10b made of rubber or the like is fixed to the lower surface of the end 10a to prevent a collision between the stopper member 10 and the abutment member 9 and to restrict the amount of upward movement of the floating bar 8. By making the width of the stopper member 10 (elastic member 10b) in the front-rear direction almost the same as the width of the closed section 8b in the front-rear direction (width of the floating bar 8 in the front-rear direction), the stopper The member 10 and the abutment member 9 are brought into contact (pressed and held) with a front-rear width that is approximately the same as the front-rear width of the floating bar 8. Reference numeral 11 denotes an elastic member that opposes the abutment member 9 from below and restricts the amount of downward movement of the floating bar 8, and is fixed to the bracket 5.

Further, when the lower rear end of the cab 1 is placed on the floating bar 8, the weight of the cab 1 applied to the floating bar 8 compresses the coil spring 7 appropriately, so that the stopper member 10 has a closed cross section. The floating bar 8 is located approximately at the center in the vertical direction within the portion 8b and allows vertical movement of the floating bar 8. However, when the load applied to the floating bar 8 decreases as the cab 1 tilts, the coil spring 7 acts with its restoring force. The force is necessary and sufficient to push up the floating bar 8 and press and hold the abutting member 9 fixed to the floating bar 8 against the elastic member 10b of the stopper member 10 to prevent the floating bar 8 from wobbling. The coil spring 7 is made up of a spring.

In the cab suspension device configured as described above, when the cab 1 is in a normal state where it is not tilted, that is, when the lower rear end 1a of the cab 1 is placed on the floating bar 8, the weight of the cab 1 is Since the coil spring 7 is moderately compressed by
As shown in FIGS. 2 and 3, the floating bar 8 is located approximately at the center in the vertical direction within the closed cross section 8b. Therefore, in this state, the floating bar 8 is allowed to move (move) in the vertical direction, so the frame 2 and the cab 1 move relative to each other to absorb vibrations.

If the cab 1 vibrates (moves) significantly in the vertical direction due to driving on a rough road, etc., the abutment member 9 will cause elastic force on the stopper member 10 or the bracket 5, respectively, as shown in FIG. 4 or FIG. Part 10
Bound and rebound of the cab 1 are suppressed due to the abutment via c and 11. Also, it goes without saying that the shock absorber 7 acts as a damper during such bounce and rebound.

On the other hand, when the cab 1 is tilted, the load applied to the floating bar 8 is reduced, so the floating bar 8 is pushed up by the restoring force of the coil spring 6, and the abutment member 9 is moved to the stopper member as shown in FIG. 10 through an elastic member 10a. In addition, since the abutting member 9 and the stopper member 10 are pressed and held with a width in the longitudinal direction that is almost the same as the width in the longitudinal direction of the floating bar 8, the cab 1 is considerably lighter than the cab 1 in a tilted state. Even if a worker stands on the floating bar 8, there is no possibility that the floating bar 8 will wobble.

Incidentally, if the widths of the closed cross-section portion 8b (abutment member 9) and the stopper member 10 are increased in the longitudinal direction, the ability to prevent wobbling will be improved accordingly, but in this case, the suspension device will become larger, so it is not practical. isn't it. Furthermore, if the width of the closed section 8b (abutment member 9) and the stopper member 10 are made smaller than the width of the floating bar 8 in the longitudinal direction, the suspension device cannot be made smaller; The closed cross-section portion 8b (abutment member 9) may reduce the wobbling prevention function.
And, by making the width of the stopper member 10 in the longitudinal direction almost the same as the width of the floating bar 8 in the longitudinal direction, the wobbling prevention function of the floating bar 8 is prevented from decreasing without increasing the size of the suspension device. Can be done.

As is clear from the above description, according to the present invention, when the cab is tilted, the floating bar, which normally floats and supports the lower rear end of the cab, is moved upward by a pair of springs, and the abutment member is turned into a stopper member. Since the floating bar is held under pressure, when a worker who is sufficiently lightweight compared to the cab stands on the floating bar, the abutment member that forms the closed section with the floating bar is held under pressure against the stopper member. continue. Therefore, the floating bar does not wobble due to the shift of the worker's weight, making it possible to improve the safety of inspection and repair work on the engine, etc. while the cab is tilted. Further, the floating bar is constituted by a so-called channel member, and a closed cross section having a width in the front and back direction that is approximately the same as the width in the front and rear direction of the floating bar is formed near both ends of the floating bar, and the stopper member is made to face inside this closed cross section. Since it suppresses the bouncing or rebound of the cab and also prevents the floating bar from wobbling during tilting, the suspension device does not become complicated.

Furthermore, the width of the closed section and the stopper member in the longitudinal direction is formed to be approximately the same as the width of the floating bar in the longitudinal direction, so that the bottom wall (abutting member) of the closed section and the stopper member are formed to have the same width in the longitudinal direction of the floating bar. Since the floating bar is configured to be pressed and held in contact with substantially the same width in the longitudinal direction, it is possible to prevent the suspension device from increasing in size without deteriorating the function of preventing the floating bar from wobbling.

[Brief explanation of the drawing]

FIG. 1 is an overall front view of one embodiment of a suspension device according to the present invention, seen from the rear of an automobile;
The figure is a partial longitudinal sectional front view showing a partially enlarged view, and Figures 3, 4, and 5 are the same as in Figure 2, showing the relative positions of the stopper member and the closed section formed on the floating bar. - It is a cross-sectional view. 1... Cab, 1a... Lower rear end of cab, 2
...Frame, 3...Suspension device, 4...
... Rear arch, 5 ... Bracket, 6 ... Coil spring, 8 ... Floating bar, 8b ... Closed section, 9 ... Hitting member, 10 ... Stopper member.

Claims (1)

[Claims] 1. In a vehicle in which the cab is supported by a suspension device on a frame on the chassis side, a pair of left and right brackets are fixed to the rear arch fixed to the frame, and the lower part of the rear end of the cab is removably supported. A floating bar is mounted on the bracket so as to be movable up and down via a pair of left and right springs, and the floating bar is composed of a U-shaped member in cross section that opens downward, and the width of the floating bar in the longitudinal direction is A closed cross-section portion that is closed in the vertical direction and has a front-back width that is approximately the same width as the floating bar is formed near both left and right ends of the floating bar, and a stopper member that has a width that is approximately the same as the front-back width of the floating bar is formed in the vicinity of the left and right ends of the floating bar. The stopper member is fixed to an integral part of the rear arch so that the tip of the stopper member faces the inside of the closed section, and when the lower rear end of the cab is supported on the floating bar, the stopper member is fixed to the rear arch. While the floating bar is positioned approximately at the vertical center of the closed cross section, when the cab is tilted, the floating bar is pressed upward and the bottom wall of the closed cross section is positioned approximately at the longitudinal width of the floating bar. A suspension device for a cab, characterized in that the spring is constituted by a spring that is pressed and held with the same width in the longitudinal direction and has a strength that prevents the floating bar from wobbling.