JPS6330621Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention includes a lever that is swingably attached to either the cab side or the frame side and has a plurality of teeth, and a lever that is attached to the other side and engages with the teeth of the lever. The present invention relates to a tilt stopper device that includes an engagement element that prevents tilt down and holds a cab in a tilted state.

The maximum tilt angle of the cab of a cab-over type vehicle is generally set at around 50 degrees due to the size of the inspection building and the load placed on the cab and chassis front structure. Therefore, when the cab is tilted, a downward moment is applied to the cab.In contrast, the hydraulic cylinder for tilting the cab is of the oil lock type, which means that when the hydraulic cylinder stops operating, the hydraulic cylinder It is required that no oil inflow or discharge occurs. This is based on the premise that the hydraulic system is completely oil-tight. However, if particles mixed into the oil for various reasons impair the oil tightness and the cab descends over the worker's head, it is dangerous, so mechanical safety devices other than the oil lock mentioned above are required. It is.

That is, in the conventional example shown in FIG. 1 (see Japanese Patent Laid-Open No. 57-77273 as an example), the cab 1 is rotatably supported around the tilt center 3 of the chassis frame 2, and there is a hydraulic pressure between the two. A hydraulic cylinder 5 of a cylinder device 4 is interposed. A lever 6 is connected to a bracket 8 on the cab 1 via a pin shaft 7, and a plurality of teeth 9 are formed on the lever 6 on the side of the hydraulic cylinder 5. This lever 6 cooperates with the hydraulic cylinder 5 to constitute a tilt stopper device 10 for preventing the cab 1 from tilting down when the oil lock is damaged. A stopper block 11 that meshes with teeth 9 of 6 is fixedly installed.

The disengagement device 12 releases the lever 6 to a non-operating position when the cab 1 is tilted down.
When the handle 13 is pulled, the arm 15 connected to the stopper block 11 via the pin shaft 14 is rotated against the force of a spring 16 interposed between the bracket 8 and the lever 6, and the lever 6 is rotated at the bent portion. 6a is pushed and released outward, and the teeth 9 and stopper lock 11 are unlocked.

Therefore, when the oil lock of the hydraulic cylinder device 4 is damaged and the cab 1 is lowered, the lever 6
One tooth 9a of the upper series of teeth engages the stopper lock 11, as shown, to prevent further lowering of the cab 1.

However, in this conventional device, when the hydraulic cylinder device 4 is operated to the down side during tilt-down, since the stopper block 11 is attached to the hydraulic cylinder 5, a bending moment as shown by arrow a acts, and therefore the hydraulic pressure The strength of the cylinder 4 and the sealing performance of the oil seal used in the hydraulic cylinder 4 are reduced.

Further, in the conventional example shown in Japanese Patent Application Laid-Open No. 57-155168, the stepped portion of the mechanical stopper 13 is locked by the locking portion 12c provided integrally with the hydraulic cylinder 12, so the same problem as described above is achieved. There's a problem.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a tilt stopper device that prevents bending moments from acting on the hydraulic cylinder and improves the strength of the hydraulic cylinder and the sealing performance of the oil seal used therein.

According to the present invention, a hydraulic cylinder device that tilts the cab, a lever that is swingably attached to the cab side and has a plurality of teeth, and an engagement that engages with the teeth of the lever to prevent tilting down. In the tilt stopper device that holds the cab in a tilted state, the engaging element is fixed to a frame side separately from the hydraulic cylinder device, and the lever engages with the engaging element by a spring member. The tooth is always biased in the direction, and the tooth is formed in a shape that does not cross over the engagement element and prevent the tilt-up during tilt-up, and the tooth and the engagement element are in contact with the tooth with a sliding surface that does not engage with the tooth. Disengagement release means is provided for moving the lever in a direction in which it is disengaged from the lever against the biasing force of the spring member.

Therefore, no couple is generated by the lever in the hydraulic cylinder device, and only axial force acts on the piston cylinder. Therefore, the strength of the hydraulic cylinder device and the sealing performance of the oil seal used therein are improved.

Hereinafter, one embodiment of the present invention will be described in detail with reference to FIGS. 2a and 2b to 4a and 4b. In these drawings, parts corresponding to those in FIG. 1 are designated by the same reference numerals.

In these drawings, the lever 6 is swingably supported by a lost motion lever 23 attached to the cab 1 together with the hydraulic cylinder 5 via a pin shaft 7a, and is moved from the hydraulic cylinder 5 in the opening direction, that is, the front, by a spring 17. An engaging element or locking pin 18, which is biased and engages the teeth 9 of the lever 6, is mounted on a bracket 19 fixed to the chassis frame 2. This bracket 1
A release lever 20 is swingably attached to the tooth 9 by a pin shaft 21, and is urged in a direction away from the teeth 9, that is, forward, by a release lever spring 22. At the tip of the release lever 20, when the release lever 20 is rotated by pulling the handle 13 and the engagement between the tooth 9 and the lock pin 18 is released, the lever 6 is rotated by pressing the tooth 9 while sliding. , a sliding surface 20a is formed to release the engagement. As shown in the figure, the upper surface of the tooth 9 is inclined so as not to get over the lock pin 18 and prevent the tilt-up during tilt-up, and the lower surface thereof is adapted to engage.

Note that the lever 6 and the hydraulic cylinder 5 can be attached to the cab side not only in this manner, but also directly to the bracket 24 fixed to the cab 1 using the pin shaft 7a as shown in FIG. 2b. good.
Further, a micro switch 25 for detecting a tilt lock is attached to the bracket 19. This microswitch 25 is for engaging the portion 6a (FIG. 3) of the lever 6 to stop the hydraulic pump when the tilt-up is completed.

Next, the effect will be explained.

When the handle 13 is pulled, the release lever 20 rotates, and its sliding surface 20a comes into contact with the tip of the tooth 9a engaged with the lock pin 18, and rotates while pressing this. As a result, the lever 6 is pushed by the teeth 9a and is moved outward against the biasing force of the spring 17, and the engagement between the teeth 9a and the lock pin 18 is released.

On the other hand, even if the hydraulic cylinder device 4 is operated in the down direction without releasing the lock of the lever 6, since the lock pin 18 is attached to a bracket 19 that is separate from the hydraulic cylinder 5, the lock pin 18 will not move as shown by arrow b. Even if a bending moment is applied, no axial force on the contraction side acts on the hydraulic cylinder 5, so that the strength of the hydraulic cylinder and the sealing performance of the oil seal used therein are improved.

Although the present invention has been described in terms of its main embodiment, other embodiments are also possible. For example, lever 6
may be connected to the cab side separately from the hydraulic cylinder 5 by a pin shaft separate from the pin shaft 7a.

[Brief explanation of drawings]

FIG. 1 is a side view showing a conventional device, FIG. 2a is a side view showing one embodiment of the present invention, and FIG. 2b is a partial view showing another embodiment of the lever and the cab side of the hydraulic cylinder. Figure 3a is a detailed side view of the lever, Figure 3b is a detailed front view of the lever, Figure 3c is a detailed view of the lever mounting section, Figure 4a is a detailed side view of the bracket, Figure 4b is a detailed front view of the release lever. 1... Cab, 5... Hydraulic cylinder, 6... Lever, 9... Teeth, 17... Spring, 18... Lock pin, 19... Bracket, 20... Release lever, 20a... Sliding surface.

Claims (1)

[Scope of utility model registration request] The cab is equipped with a hydraulic cylinder device that tilts the cab, a lever that is swingably attached to the cab side and has a plurality of teeth, and an engagement element that engages with the teeth of the lever to prevent the cab from tilting down. In the tilt stopper device that maintains a tilted state, the engaging element is fixedly installed on the frame side separately from the hydraulic cylinder device, and the lever is constantly biased by a spring member in a direction to engage the engaging element. The tooth is formed in a shape that does not prevent the tooth from climbing over the engaging element when tilting up, and the engagement between the tooth and the engaging element is released while contacting the tooth with a sliding surface that does not engage with the tooth. The tilt stopper device is further provided with an engagement release means for moving the lever in a direction in which the lever is moved against the biasing force of the spring member.