JPH0125055Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a link structure for transmitting operating force for a tail cab with suspension, and is particularly applicable to a cab suspended on a vehicle body frame and moved up and down around the tail center while driving. Mutual interference that occurs due to relative displacement between the cab and frame in a link system that connects a gear shift lever and a transmission to transmit operating force, such as a link system that connects a series of links from the to the vehicle body frame, i.e., the cab side. The present invention relates to a link structure for transmitting operating force of a tail cab with a suspension, which can minimize the difference in movement between the side and the frame side and improve the safety of the link mechanism.

[Prior Art] Generally, in a cab-over type vehicle in which the cab covers the engine from above, the entire cab can be tilted forward in the direction of travel for engine maintenance or the like. In addition, when the cab is in its normal resting position, that is, in a running state, it is suspended by a suspension mechanism provided on the vehicle body frame, so that vibrations from the road surface are damped and a good ride comfort is obtained.

By the way, since a steering mechanism, a parking brake mechanism, etc. are installed between the cab and the body frame, there is a large relative movement between the cab and the body frame when the cab is tilted, and the cab is moved up and down when driving. A structure that is as insensitive to vibration as possible is required.
In particular, many gear shift levers installed on the cab use a link mechanism to transmit the operating force to the transmission on the vehicle frame side, and prevent mutual interference between the links due to tilting or vertical movement of the cab. There was a demand for a structure that would suppress this.

Therefore, the applicant of the present invention previously proposed a "remote control device for a tail cab type automobile with a cab suspension" as shown in FIG. Reference numeral 1 denotes a cab, and the front end of the cab 1 is pivotally supported at the other end of a link arm 3 which has its base end pivoted to the vehicle body frame 2 and forms a tail center C. Link arm 3 and cab 1
An appropriate spring is provided between them, and the maximum amount of approach between them is regulated by a stopper rubber. The rear of the cab 1 is supported on a vehicle body frame 2 via a suspension system. The cab 1 is tilted around a tail center C via the link arm 3. At the beginning of tailing operation, the front end of cab 1 descends, or sinks,
The distance between the cab 1 and the link arm 3 approaches, and the cab 1 and the link arm 3 are brought into pressure contact via the stopper rubber, and the cab 1 and the link arm 3 are integrally tilted forward around the tail center C. Reference numeral 4 designates a gear shift lever, and the operating force applied to this lever is applied via a cab-side link 5, which is pivotally supported to the cab 1 with a bracket, and a frame-side link 6, which is not shown, which is pivotally supported to the vehicle body frame 2 with a bracket. configured to be communicated to the transmission. The purpose of the above invention is to connect the cab side link 5 and the frame side link 6 on the same axis of the tilt center C, where when the cab 1 is tilted, there is no relative movement between the cab 1 and the vehicle body frame 2, and only rotation occurs. link rod 7
The applicant has achieved this goal by pin-jointing the links to suppress mutual interference between the links on the cab side and the frame side, thereby improving the structural safety of the entire link for transmitting operating force.

[Problems to be solved by the invention] However, the above-mentioned invention merely combines the tail center C and the pin joint 8, and as shown in FIG. As particularly shown by _S1 in FIG. 2, this is achieved by allowing the movement trajectories B and D of the cab side link 5 and the link rod 7 to differ greatly, that is, to interfere, at the pin joint 8. The gear shift lever 4, which forms the end of the link system, was swinging a lot, and the transmission gears were being moved to arbitrary positions.

For this reason, the movement of the entire link in the operating direction due to the vertical movement of the cab 1 while the vehicle is running cannot be sufficiently suppressed, which may cause the shift lever 4 to shake or, in the worst case, cause the gear to disengage.

Also, Utility Application No. 57-109296 (Utility Application No. 59-13372)
The cab tail device described in the above publication also does not have a mechanism for aligning and extending the link rod on the axis of the link arm and positioning one connecting end coaxially with the tail center, so the above-mentioned problem cannot be solved. I was afraid.

The present invention has been devised in view of the above-mentioned problems and with the aim of improving the above-mentioned invention.

The inventor of the present invention has proposed that the center of movement E of the cab-side link 5 based on the vertical movement near the tail center C of the cab 1 during running is approximately on the axis F of the link arm 3 when the cab 1 is stationary, as shown in FIG. Focusing on the fact that the pin joint 8 is located near the tail center C, we not only align the pin joint 8 coaxially with the tail center C, but also align the link rod 7 that connects the cab side link 5 and the frame side link 6 in the lateral direction of the vehicle body. That is, by extending and arranging the link arm 3 so as to coincide with the axis F of the link arm 3 that guides the cab tail when viewed from the horizontal direction, the movement paths B and G of the links 5 and 7 are aligned as much as possible as shown in FIG.
The present invention was completed by discovering that discrepancies, or interference, as shown by S ₂ and S ₂ can be suppressed.

The purpose of this invention is to prevent movement due to relative displacement between the cab-side link and frame-side link when the cab is tilted or while driving, thereby preventing swinging of the shift lever and gear slippage, and improving the safety of the link system for transmitting operating force. An object of the present invention is to provide a link structure for transmitting operating force of a tail cab with suspension, which improves the performance.

[Means for solving the problem] In order to achieve the above object, the link structure for transmitting operating force of the tail cab with suspension of the present invention includes a link arm whose base end is pivotally supported on the vehicle body frame and forms the tail center. A cab-side link that is provided on the tail cab with suspension pivotally supported at the other end and transmits the operating force, a frame-side link that is provided on the vehicle body frame and transmits the operating force to the operated device, and a link that is located on the axis of the link arm. It is connected by a link rod which is extended in line with the tail center and whose one connecting end is positioned coaxially with the tail center.

[Function] While the vehicle is running, the cab is entirely moved up and down by the suspension mechanism along a turning locus of the link arm that rotates around the tail center. Due to this vertical movement, at one connecting end of the cab-side link and the link rod, the cab-side link attempts to rotate and move along a trajectory of the cab-side link that approximates the trajectory of the link arm. , the link rod tries to move while rotating the second lever of the frame-side link with its axial length as a radius. At this time, the one connecting end of the cab side link and the link rod is positioned coaxially with the tail center, and the center of movement of the cab side link is aligned on the axis of the link arm or its extension. Since the link rods are provided in parallel with each other, it is possible to suppress discrepancies in the trajectories of the cab side link and the link rod as much as possible, thereby suppressing mutual interference between the two link systems during driving, and reducing vibration of the gear shift lever. This can prevent transmission gears from slipping out.

Furthermore, when tilting the cab, the one connecting end that connects the cab side link and the link rod rotates coaxially with the tilt center, thereby preventing mutual interference between the trajectories of the cab side link and the link rod. can be suppressed.

[Embodiment of the invention] A preferred embodiment of the invention will be described below in detail with reference to the accompanying drawings.

As shown in FIGS. 3 and 4, the cab 1 has a base end 3a pivoted to the vehicle body frame 2 via a bracket 9, and is pivoted to the other end 3b of a link arm 3 forming a tail center C. , is suspended on the vehicle body frame 2 by a suspension mechanism 10. The front end is supported in this example on a leaf spring, one end of which is fixed to the link arm 3, and the other end is supported on a coil spring.

In addition, a stopper rubber is provided between the two,
The position regulation during maximum approach and the integral connection by the stopper rubber in close contact during tilting are the same as the conventional device shown in FIG.

The cab 1 is tilted during engine maintenance, etc., and is guided by the link arm 3 from above the vehicle body frame 2 and relatively moved forward in the running direction around the tail center C. It is designed to move gently up and down on the vehicle body frame 2 around the center C via the link arm 3.

As shown in FIG. 2, the movement locus H of an arbitrary point Z on the front part of the cab ₁ is determined by It is possible to approximate a trajectory whose radius is one side m ₁ parallel to the axis F of the link arm 3.

In this way, the body frame 2
Between the cab 1, which is moved up and down, and the vehicle body frame 2, there is a transmission, which is an operated device provided on the body frame 2 side, and which applies an operating force to a gear shift lever 4, which is an operating stick provided on the cab 1. Link system 11 for transmitting operating force to the shaft
are connected in series, and the operating force transmission link system 11 consists of two systems, one for the select side 11a and the other for the shift side 11b, each of which is configured to transmit the operating force separately.

The operating force transmission link system 11 is pivotally supported on the cab 1 via a bracket 12, and is connected to a series of cab side links for transmitting the operating force applied to the gear shift lever 4 while following the vertical movement of the cab 1. Link 5
and a series of frame side links 6 which are pivotally supported on the vehicle body frame 2 via a bracket 13 and are connected via a link rod 14 for transmitting operating force to the transmission.

Further, the point of action of the first lever 15 forming the output end of the cab side link 5 and the point of force of the second lever 16 forming the input end of the frame side link 6 are connected to the link rod 1.
4, and a connecting end 14a with the cab side link 5 as one connecting end of this link rod 14.
constitutes a free end that can freely rotate on the same axis of the tail center C.

Furthermore, in the link structure of the present invention, the link rod 1 connects the cab side link 5 and the frame side link 6.
4 is extended and aligned with the axis F of the link arm 3 or an extension thereof.

Further, the link rod 14 and the link arm 3 are provided in parallel when viewed from above the vehicle.

In addition, the vertical movement of the front part of the cab 1 while driving is
As shown in FIG. 2, since the link arm 3 follows the turning trajectory A around the tail center C, the point of action of the first lever 15, which is the output end of the cab side link 5, also forms a parallelogram M shown in the figure together with the cab 1. One of the sides of ₂ that is on the extension of the axis F of the link arm 3
Since the trajectory B has a radius of m ₂ , in order to reduce mutual interference with the link rod 14 as much as possible in a relatively small amplitude range, the relatively small discrepancy S ₂ between the mutual trajectories B and G in FIG. The structure is such that the movement locus G of the link rod 14 follows the movement locus B of the first lever 15 as much as possible so as to suppress the movement to _S2 .

Next, the operation of the present invention will be described.

When the vehicle is running, the entire cab 1 is moved up and down by the suspension mechanism 10 along a turning trajectory A of the link arm 3 rotating around the tail center C, as shown in FIG. Due to this vertical movement, the first lever 15 in the cab-side link 5 attempts to move while rotating along a trajectory B that approximates the rotation trajectory A of the link arm 3 at the connecting end 14a between the cab-side link 5 and the link rod 14. At the same time, the link rod 14 attempts to move while rotating the second lever 16 in the frame-side link 6, using its axial length as a radius. In this regard,
The link structure of the present invention, as shown in FIG.
Since the link rod 14 is provided in parallel with the axis F of the link arm 3 on which the center of movement E of the cab-side link 5 rides, or on its extension, the link rod 14 is positioned coaxially with the tail center C. In other words, it is possible to suppress the discrepancy between the trajectories B and G of the cab side link 5 and the link rod 14, thereby suppressing mutual interference between both link systems during driving, and preventing swinging of the shift lever 4 and gear slippage of the transmission. can do.

Also, when tilting cab 1,
As the connecting end 14a between the cab side link 5 and the link rod 14 rotates coaxially with the tail center C, the link B,
G mutual interference can be suppressed.

5 to 7 show modifications of the present invention. The modification shown in FIG.
The cab 1 is pivoted to the link arm 3 at the front of the cab, and the center of movement E of the cab side link 5 is
is located on the link rod 14 which is provided on the extension of the axis F of the link arm 3. Therefore, the movement trajectory B of the cab side link 5 is
This overlaps the movement locus G of the link rods 14 that are turned on the same side, and interference between the links can be further suppressed than in the embodiments shown in FIGS. 3 and 4.

In the modification shown in FIG. 6, the connecting end 14b of the link rod 14 and the frame-side link 6 is located at the tilt center C. That is, the connection end 1 between the force point of the second lever 16, which is pivotally supported on the vehicle body frame 2 via the bracket 13, and the link rod 14.
4b is located coaxially with the tail center C.

In the modification shown in FIG. 7, the link arm 3 of the modification shown in FIG. 6 is pivoted to the cab 1 in front of the bracket 9.

It goes without saying that the modified embodiments shown in FIGS. 5 to 7 as described above also have the same effects as the embodiments shown in FIGS. 3 and 4.

[Effects of the invention] As described above, in the link structure for transmitting operating force of the tail cab with suspension of the present invention, the base end is pivoted to the vehicle body frame and is pivoted to the other end of the link arm forming the tail center. A cab-side link provided on the tail cab with suspension and transmitting the operating force, and a frame-side link provided on the vehicle body frame and transmitting the operating force to the operated device.
The link arm is connected by a link rod extending along the axis of the link arm and having one connecting end positioned coaxially with the tail center.
The movement locus of the link rod can be made to follow the movement locus of the cab side link as much as possible, and movement due to relative displacement between the cab side link and the frame side link during cab tailing and driving can be prevented, and the shift lever This has the effect of improving the safety of the operating force transmission link system by preventing vibration and gear slippage.

[Brief explanation of the drawing]

Fig. 1 is a side sectional view showing a conventional example, Fig. 2 is a principle diagram showing the basic structure of the present invention, Fig. 3 is a side sectional view showing a preferred embodiment of the present invention, and Fig. 4 is a perspective view thereof. 5 to 7 are side sectional views showing modified embodiments. 1... Cab, 2... Body frame, 3... Link arm, 5... Cab side link, 6... Frame side link, 14... Link rod, 14a,
14b... Connection end, C... Tailed center, F...
...Axis of the link arm.

Claims (1)

[Scope of utility model registration request] The base end is pivotally supported on the vehicle body frame to form the tail center.The cab-side link is provided on the suspension-equipped tail cab whose other end is pivotally supported on the other end of the link arm to form the tail center, and the cab-side link is provided on the vehicle body frame to transmit operating force. Operation of a tail cab with suspension, in which a frame-side link that transmits operating force is connected by a link rod that extends along the axis of the link arm and has one connecting end positioned coaxially with the tail center. Link structure for force transmission.