JPH0522267U - Cab Support Device - Google Patents

Abstract

(57) [Summary] [Purpose] In a cab for a conventional construction machine, a plurality of supports having a similar cushioning effect are provided between a cab and a frame for an upper swing body. As a result, the cab oscillates when working on the construction machine, resulting in a decrease in working accuracy. Further, when traveling, the cushioning effect is too small and the riding comfort is poor. The present invention aims to solve the above problems. [Structure] The front end of the lower end of the cab is screwed to the frame of the upper revolving structure by a hinge member so as to be rotatable in the front-rear direction, and a cab support cylinder is provided between the girder portion at the rear part of the cab and the frame. , Also provided accumulator on the upper revolving structure,
The accumulator and the cab support cylinder are communicated with each other through a slow return valve and an electromagnetic on-off valve, while a switch is provided in an electric circuit, and the electromagnetic on-off valve is switched by operating the switch.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a support device for a driver's cab mounted on construction machines such as hydraulic excavators and work vehicles.

[0002]

[Prior Art]

 FIG. 4 is a cross-sectional view of a main part of a cab 1 according to the related art mounted on a hydraulic excavator (not shown). In the figure, 2 is a cab in the cab 1, 3 is a driver's seat, 4 is a floor plate, 5 is a frame of an upper swing body for a hydraulic excavator, 6 is a plurality of supports, 7 is a buffer member of the support 6, and 8 is a support member. It is a tightening bolt. FIG. 5 is a plan view of a main part viewed from AA in FIG. In the conventional cab 2, a plurality of cushioning supports 6 are arranged on the lower surface side of the floor plate 4, and the cab 2 is attached to the frame 5 via the plurality of supports 6.

[0003]

[Problems to be solved by the device]

 The hydraulic excavator runs for moving, or stops to perform various work. As a structure for mounting the hydraulic excavator in the operator's cab, a plurality of supports having the same cushioning effect are provided between the cab and the frame for the upper swing body. If the cushioning effect of this support is too large, the swinging of the cab and the driver itself during the work of the hydraulic excavator will be large and the work accuracy and efficiency will be reduced.Therefore, the cushioning effect of the support is set quite small. . As a result, the cushioning effect when the hydraulic excavator was running was too small, and the ride comfort of the driver was poor. The problems to be solved by the present invention are the above problems.

[0004]

[Means for Solving the Problems]

 According to the present invention, the lower end front part of the cab for a cab mounted on the construction machine is hinged to the frame of the upper revolving structure by the hinge member so as to be rotatable in the front and rear directions, and the girder part at the rear part of the cab is used. A cab support cylinder is installed between the frame and the cab support cylinder so that it can be expanded and contracted by operating the switching valve, and an accumulator is provided on the upper revolving structure, and the accumulator and the cab support cylinder are connected to each other. Is connected via a slow return valve and a solenoid on-off valve, while a switch is provided in the electric circuit, and the solenoid on-off valve is switched by operating the switch.

[0005]

【Example】

 FIG. 1 is a circuit diagram showing a supporting device of the present invention. In the figure, 10 (portion in phantom line) is a cab for driver's cab (9), 11 (portion in phantom line) is girder of cab 10, 12 is cab support cylinder, 5'is frame of upper revolving structure, 13 Is a switching valve for controlling the cab support cylinder 12, 14 is a hydraulic pump, 15 is an accumulator, 16 is a slow return valve, 17 is an electromagnetic opening / closing valve, 18 is a solenoid of the electromagnetic opening / closing valve 17, 19 is an electric circuit, and 20 is The switch 21 is a power source. FIG. 2 is a side view of essential parts showing a mounting structure of the cab support cylinder 12 in FIG. Reference numeral 22 is a bracket fixed to the girder portion 11, 23 is a bracket fixed to the frame 5 ', 24 and 25 are pivot pins, and 26 is a hinge member. FIG. 3 is a partially cutaway rear view of the hydraulic excavator 27 including the supporting device of the present invention. In the figure, 28 is an upper swing body of the hydraulic excavator 27, and 29 is a lower traveling body.

Next, the structure of the supporting device of the present invention will be described with reference to FIGS. The lower end front part of the cab 10 is hinged to the frame 5'of the upper revolving structure 28 so as to be rotatable in the front-back direction by the hinge member 26, and the girder part 11 at the rear part of the cab 10 and the frame 5'are A cab support cylinder 12 is provided between the cab support cylinder 12 and the cab support cylinder 12 can be expanded and contracted by operating the switching valve 13. Further, an accumulator 15 is provided on the upper revolving structure 28, and the accumulator 15 and the cab support cylinder are supported. The cylinder 12 is communicated with the slow return valve 16 and the electromagnetic on-off valve 17, while the electric circuit 19 is provided with a switch 20, and the electromagnetic on-off valve 17 is switched by operating the switch 20. did.

Next, the operation of the supporting device of the present invention will be described. The cab support cylinder 12 can be extended or contracted by operating the switching valve 13, so that the cabin 10 is set to a predetermined normal position and the switching valve 13 is set to the neutral position. First, a case where the hydraulic excavator 27 works will be described. When operating the hydraulic excavator 27, the switch 20 in the electric circuit 19 is turned off. Since the solenoid 18 is not energized, the solenoid opening / closing valve 17 is in the shutoff oil passage position B. Since the bottom side oil chamber 30 and the rod side oil chamber 31 of the cab support cylinder 12 are oil-tight from the neutral position of the switching valve 13 and the shutoff oil passage position a of the electromagnetic opening / closing valve 17, respectively, the cab support cylinder 12 Is locked. Since the cab 10 is fixed to the frame 5'of the upper swing body 28, it is possible to reduce the swinging of the cab caused by the cushioning support as in the prior art.

Next, a case where the hydraulic excavator 27 travels will be described. When the hydraulic excavator 27 is running, the switch 20 in the electric circuit 19 is turned on. Since the solenoid 18 is energized, the electromagnetic opening / closing valve 17 is switched from the shutoff oil passage position a to the opening oil passage position b. Therefore, the bottom side oil chamber 30 of the cab support cylinder 12 communicates with the accumulator 15 via the opening oil passage position b of the electromagnetic opening / closing valve 17 and the slow return valve 16, and at the same time, the rod side oil chamber 31 of the cab support cylinder 12 is The solenoid valve 17 communicates with the oil tank 32 via the open oil passage position b. As a result, the cab 10 is supported in the floating state, so that the ride comfort is good during running.

[0009]

[Effect of the device]

 As described above, in the present invention, the lower end front part of the cab for the cab equipped on the construction machine is hinged to the frame of the upper revolving structure by the hinge member so as to be rotatable in the front-rear direction and the rear part of the cab. A cab support cylinder is provided between the girder portion and the frame so that the cab support cylinder can be expanded and contracted by operating the switching valve, and an accumulator is provided on the upper revolving structure. The cab support cylinder is connected to the cab support cylinder through a slow return valve and an electromagnetic on-off valve. On the other hand, a switch is provided in an electric circuit, and the electromagnetic on-off valve is switched by operating the switch. As a result, when the construction machine performs work, if the switch in the electric circuit is turned off, the cab support cylinder is locked and the swing of the cab and the driver himself is reduced. Therefore, the driver's feeling of living in the work is improved, and the work accuracy and work efficiency are improved. When the construction machine is traveling, if the switch is turned on, the cab support cylinder will float and the cushioning effect will be fully exerted, resulting in good riding comfort during traveling.

[Brief description of drawings]

FIG. 1 is a circuit diagram showing a supporting device of the present invention.

FIG. 2 is a side view of essential parts showing a mounting structure of the cab support cylinder in FIG.

FIG. 3 is a partially cutaway rear view of a hydraulic excavator provided with the supporting device of the present invention.

FIG. 4 is a sectional view of a main part of a conventional cab.

5 is a plan view of an essential part seen from AA in FIG. 4. FIG.

[Explanation of symbols]

 1,9 Driver's cab 2,10 Cab 5,5 'frame 11 Girder section 12 Cab support cylinder 13 Switching valve 15 Accumulator 16 Slow return valve 17 Electromagnetic on-off valve 19 Electric circuit 20 Switch 28 Upper revolving structure

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Eiji Sakiya 9-16-35-14 Nishihara, Asanan-ku, Hiroshima-shi, Hiroshima Prefecture 72-72 (72) Koichiro Niwada 731- Minamishitan, Gion-cho, Asanan-ku, Hiroshima-shi, Hiroshima Prefecture 1 (72) Creator Hidemitsu Shimazu 9-2-11-101 General Manager Izumi-ku, Sendai City, Miyagi Prefecture

Claims (1)

[Scope of utility model registration request] 1. A construction machine in which a cab for a driver's cab is mounted on a frame of an upper revolving structure via a buffer support, and a front end of a lower end of the cab is rotatably movable forward and backward by a hinge member. It is hinged to the frame, and a cab support cylinder is arranged between the girder part at the rear of the cab and the frame so that the cab support cylinder can be expanded and contracted by operating the switching valve. An accumulator is provided, and the accumulator and the cab support cylinder are communicated with each other via a slow return valve and an electromagnetic opening / closing valve,
On the other hand, a cab supporting device characterized in that a switch is provided in an electric circuit, and the electromagnetic on-off valve is switched and operated by operating the switch.