JPH0342123Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a sealed structure for a control lever that operates an actuator in a hydraulic working machine such as a hydraulic excavator or a hydraulic crane.

FIG. 1 is a side view showing the external appearance of a hydraulic excavator taken as an example of a hydraulic working machine, in which 1 is a lower traveling body, 2 is an upper revolving body placed freely on the lower traveling body 1, and 3 is an upper part. An operator's cab (hereinafter referred to as a cab) provided on the revolving structure 2, 4 a boom provided on the upper revolving structure, and 5 an actuator such as a hydraulic motor or a hydraulic cylinder.

Fig. 2 is a cross-sectional view schematically showing the inside of the cab 3, Fig. 3 is a bottom view of Fig. 2, and Fig. 4 is A-A of Fig. 3.
It is a line sectional view, and 6 is a cab floor surface which is the floor surface of the cab 3. A pair of brackets 7 are fixed to the back surface of the cab floor 6, and a shaft 8 installed between these brackets 7 has a bearing 9.
The link 10 is rotatably supported via the link. At the center of this link 10 is a bracket 11.
One end of the rod 13 is connected to the hydraulic switching valve 12, and the other end of the rod 13 is rotatably connected to the bracket 11 via a pin 14. An operating lever 15 is fixed to the link 10 on the opposite side of the bracket 11, and most of the operating lever 15 projects into the cab 3 through an opening 16 formed in the cab floor plate 6.

When the operating lever 15 is moved in the direction of the arrow shown in FIG.
0 is rotated by a predetermined angle about the shaft 8 as the rotation axis, and the hydraulic switching valve 12 is operated via the rod 13. When the switching operation of the hydraulic switching valve 12 is performed,
Engine and hydraulic pump (both not shown)
Each actuator 5 is
are operated, and the operations of these actuators 5 perform various operations such as vertical movement of the boom 4, traveling of the lower traveling body 1, and turning of the upper rotating body.

In this way, in the above-mentioned hydraulic excavator, each actuator 5 is operated by moving the operating lever 15, so the opening 16 is formed to a degree that does not impede the movement of the operating lever 15. Therefore, noise generated by the engine, hydraulic pump, etc. enters the inside of the cab 3 through this opening 16, causing discomfort to the driver inside the cab 3. Therefore, sealed structures have been conventionally employed to reduce such noise.

5 and 6 show conventional examples of such a sealed structure, in which FIG. 5 is a plan view of the rubber plate, and FIG. 6 is a sectional view showing the state in which the rubber plate is attached. In these figures, the rubber plate 17 has a through hole 17a having approximately the same diameter as the operating lever 15, and a pair of linear slits 17b communicating with the through hole 17a, and its outer shape is larger than that of the opening 16. It is formed in a large size. This rubber plate 17 has an opening 1
The operation lever 15 is fixed to the back surface of the cab floor plate 6 so as to cover the through hole 1 in the neutral position.
7a, and the linear slit 17b is opened by the operating portion 15 so as not to interfere with the movement of the operating lever 15.

However, in the conventional sealed structure configured in this way, if the wall thickness of the rubber plate 17 is made too thin, the noise reduction effect cannot be achieved sufficiently. However, because of this, the operating lever 15 that has entered the linear slit 17b receives a large frictional resistance from the rubber plate 17, and the operating force of the operating lever 15 becomes heavy. It was hot. Further, when the operating lever 15 is moved, the rubber plate 17 has a through hole 17a and an operating lever 1.
Since the opening of the linear slit 17b widened by the opening 5 is formed, there is a disadvantage that noise reaches the inside of the cab 3 through these openings.
Furthermore, there is a drawback that the linear slit 17b portion of the rubber plate 17 is worn out due to repeated use of the operating lever 15.

An object of the present invention is to provide an operating lever sealing structure for a hydraulic working machine that eliminates the drawbacks of the prior art described above.

In order to achieve this purpose, the present invention connects a rod for operating a hydraulic switching valve to a link, and attaches an operating lever to this link for rotating the link.
In a hydraulic working machine in which the operating lever protrudes into the operator's cab from an opening provided in the floor of the operator's cab, the portion of the link where the operating lever is attached to the floor opposite to the operator's cab and the The present invention is characterized in that a frame body is attached to cover the opening, and a seal portion is provided on the frame body to seal the outer periphery of the link extending from the frame body.

When the operating lever is operated, the link rotates in response, and the hydraulic switching valve is driven. At this time,
Since the outer periphery of the link rotates while remaining sealed, external noise is prevented from entering.

Embodiments of the present invention will be described below with reference to the drawings.

7 is a perspective view showing an embodiment of the frame body, FIG. 8 is a bottom view showing the attached state of the frame body shown in FIG. 7, and FIG. 9 is a sectional view taken along the line B-B in FIG. 18 is a frame body, 19 is a rubber plate, and 20 is a screw, and parts corresponding to those in FIGS. 2 to 6 are given the same numbers. In these figures, the frame 18 is formed to have an open top and both sides, and rubber plates 19 serving as seals are fixed to these sides by appropriate means such as adhesive. The rubber plate 19 is provided with a circular portion 19a having approximately the same diameter as the outer diameter of the link 10 and a linear cut 19b, and the frame 18 is provided with a plurality of mounting holes 18a.

The frame 18 with the rubber plate 19 fixed in this way is
The notch 19b of the rubber plate 19 is expanded to form a circular portion 19a.
After matching the outer peripheral surface of the link 10, it is fixed to the back surface of the cab floor plate 6 with a plurality of screws 20, and the opening 16 made in the cab floor plate 6 is connected to the frame 18 and both rubber plates 19. sealed by.

In the operation lever sealed structure constructed as described above, the outer peripheral surface of the link 10, which is the rotating part, is sealed with the rubber plate 19, so that the link 10 can be rotated by moving the operation lever 15. Even in this case, the rubber plate 19 suffers little wear and the sealing effect does not decrease.

FIG. 10 is a bottom view showing another embodiment of the operating lever sealing structure according to the present invention. This embodiment differs from the first embodiment described above in that the frame 18 is formed so that only the upper part and one side are open, and the other side is closed in advance. The rubber plate 19 is fixed to the portion.

The frame body 18 having the rubber plate 19 fixed to one side in this way connects the circular part 19a of the rubber plate 19 to the link 10.
After matching the outer peripheral surface of the bracket, it is fixed to the back surface of the cab floor plate 6 so as to cover the opening 16 and the bracket 7. In this embodiment, one rubber plate 19 that seals the outer circumferential surface of the link 10 can be omitted, making it possible to reduce costs and further reduce noise.

Note that in each of the embodiments described above, the frame 18
Although the rubber plate 19 is used as the seal portion provided in the seal portion, a synthetic resin plate may be used instead of the rubber plate 19 as the seal portion. When a synthetic resin plate is used as a seal,
In this case, it is difficult to loosely fit the synthetic resin plate to the outer peripheral surface of the link 10 due to elastic deformation.
The link 10 is supported on the bracket 7 with the circular part of the synthetic resin plate loosely fitted into the link 10 in advance, and then the synthetic resin plate is joined to the frame 18 fixed to the cab floorboard 6, or the synthetic resin plate is attached to the frame 18. It is necessary to devise measures such as dividing it into several parts and joining them to the frame 18 fixed to the cab floorboard 6.

As explained above, according to the present invention, the outer peripheral surface of the link, which is a rotating part, is sealed with a sealing part such as a rubber plate, and the opening for driving the operating lever is covered with this sealing part and the frame. Therefore, a sufficient noise reduction effect can be achieved without increasing the operating force of the operating lever, and wear of the seal portion can be reduced.

[Brief explanation of drawings]

Figure 1 is a side view showing the external appearance of the hydraulic excavator, Figure 2 is a sectional view schematically showing the inside of the cab of the hydraulic excavator shown in Figure 1, Figure 3 is a bottom view of Figure 2, and Figure 4 is the A sectional view taken along the line A-A in FIG. 3, and FIGS. 5 and 6 show an example of a conventional operation lever sealed structure.
FIG. 5 is a plan view of the rubber plate, FIG. 6 is a sectional view showing how the rubber plate is attached, and FIGS. 7 to 9 show the operating lever sealing structure according to the first embodiment of the present invention.
Fig. 7 is a perspective view of the frame and the seal part, Fig. 8 is a bottom view showing how the frame is attached, and Fig. 9 is B--B in Fig. 8.
A sectional view taken along line B and FIG. 10 are bottom views of the operating lever sealing structure according to the second embodiment of the present invention. 3... Cab, 6... Cab floor plate, 7... Bracket, 8... Shaft, 9... Bearing, 1
0...Link, 15...Operation lever, 16...Opening, 18...Frame, 19...Rubber plate (sealing part), 20...Screw.

Claims (1)

[Scope of utility model registration request] In a hydraulic working machine, a rod for operating a hydraulic switching valve is connected to a link, an operating lever for rotating the link is attached to this link, and this operating lever protrudes into the operator's cab through an opening provided in the floor of the operator's cab. , a frame body covering a portion of the link where the operation lever is attached and the opening portion is attached to the floor surface on the opposite side of the driver's cab; A closed structure for an operating lever of a hydraulic working machine, characterized by having a seal part that seals the outer periphery of a link.