JPH0322364Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a steering device for a construction work vehicle having a swivel base.

In a full-swing type construction work vehicle, the forward and backward movement direction of the vehicle is determined by the traveling device. Therefore, when the swivel base is facing forward, the direction of the swivel base and the direction of the lower traveling body are the same, and the vehicle body moves in the direction in which the driver operates the control lever. If you are turning more than 90 degrees, that is, if you are facing backwards, this will not match.
The direction in which the control lever is operated is opposite to the direction in which the vehicle is moving, and even if the driver operates the control lever forward based on himself, the vehicle body will move to the rear of the driver, which is extremely dangerous. . In construction vehicles that have a swivel base, when the swivel base is facing backwards, the operating direction of the control lever and the direction of movement of the vehicle body are opposite, so the driver must always keep this in mind when moving the vehicle body. This must be kept in mind, and if operated carelessly, there is a risk of an unexpected accident. This is especially true when working in a narrow space or loading onto a trailer for transportation.
Therefore, when operating the traveling device, the driver has to constantly check the direction of the lower traveling body while operating the vehicle, which is cumbersome and inefficient.

This idea was devised in view of the above points, and its purpose is to ensure that the direction in which the driver operates the operating lever always matches the direction in which the vehicle body moves, regardless of whether the swivel base is facing forward or backward. That is.

The structure of this invention consists of a swivel base position detection device comprising a semicircular cam provided on the undercarriage, a limit switch provided at the bottom of the swivel base and engaged with the cam; A fixing device consisting of an operating solenoid valve, an air cylinder with fork ends at both ends, a fulcrum rod that is inserted into a hole in the bracket and fixed by pressing with the fork ends, and a switching valve that controls the travel motor and an operating lever. It consists of a lever supported by the fulcrum rod.

When the swivel base is facing backwards, the air cylinder is switched via the limit switch and solenoid valve to fix the fixed rod on the opposite side, so the direction of operation of the control lever is reversed and the driver is aware that it is now facing backwards. Not only is it very convenient because you can operate it yourself without having to do anything, but you also need to consider the direction of operation of the control lever and the direction of movement of the vehicle body when working in a narrow space or loading onto a trailer. It is easy to operate and safe.

Hereinafter, embodiments of the present invention will be described in detail based on the drawings.

1 is an undercarriage body, 2 is a swivel base, and the undercarriage body 1
A semicircular cam 3 is protruded from the upper part of the swivel base 2 concentrically with the center of rotation of the swivel base 2, and a cam 3 is provided at the bottom of the swivel base 2 when the swivel base 2 is rotated more than 90 degrees left and right from the front. A limit switch 4 is installed at a position where it engages with the limit switch 3. 5 is an air source, 6 is a solenoid valve,
7 is an air cylinder, these are connected by a pipe 8, and a lead wire 9 is connected to the solenoid valve 6 from the limit switch 4. The solenoid valve 6 is engaged with the cam to turn on and switch the solenoid valve 6 to the left side. In addition, a lever 15 having two selection fulcrums is provided in the middle of a link mechanism connecting the operation lever 21 and the switching valve 25, and the lever 15 is provided with two selection fulcrums.
5, an air cylinder 7 is used to selectively fix the
and the two brackets 12, 12' on the swivel base 2.
It was established in Air cylinder 7 is a double rod type.
The left and right piston rods 10, 10' have fork ends 11, 11' at their tips, respectively. 1
2 and 12' are brackets fixed to the swivel base 2, 13 and 13' are holes drilled in the brackets 12 and 12', and fixing rods 1 are inserted into the holes 13 and 13'.
4 and 14' are fitted and inserted, respectively. The fixing rods 14, 14' are used as fulcrums when the lever 15 rotates.
and are rotatably supported at the intermediate portions of the levers 15, respectively. A pin 17 connects the rod 18 to the opposite end of the lever 15 from the connection point of the fixed rod 14'.
The rod 18 is connected to the bell crank 1.
9. It communicates with an operating lever 21 via a rod 20, and the lever 15 can be rotated by operating the operating lever 21. A rod 22 is connected to the lever 15 by a pin 23 at the midpoint between pins 16' and 17, and the other end is connected to a switching valve 25 for controlling the travel motor 24, and the switching valve 25 can be operated by the rod 22. .

The position of the pin 16 at the connection point between the lever 15 and the fixed rod 14 is such that the ratio of the distance from the pin 16 to the pin 23 to the distance to the pin 17 is 1:2. Therefore, pin 16'
Since the ratio of the distance from to pin 23 to pin 17 is 1:2, pin 1
7 and pin 23 are only rotated in opposite directions, but the amount of movement of the rod is the same. Further, 26 is a hydraulic pump.

The present invention is constructed as described above, and to explain the case in which it actually operates, when the swivel base 2 is facing in the same direction as the undercarriage 1, that is, facing correctly, the limit switch 4 is The solenoid valve 6 is located away from the cam 3 protruding from the traveling body 1 and is in the OFF state, so the solenoid valve 6 communicating therewith is located on the right side as shown in FIG.
The piston rod 10 of the air cylinder 7 extends to the right, and the fork end 11 is attached to the bracket 1.
Fixing rod 14 inserted into hole 13 of No. 2 is inserted into hole 1.
It is fixed by pressing it against the side of 3. On the other hand, the left fork end 11' does not exert any influence on the fixing rod 14' fitted into the hole 13', so that it can freely move in the axial direction within the hole 13'.
In this way, one of the fixed rods 14 is fixed and the other fixed rod 14' is free, so that the lever 15, which is pivotally supported on the fixed rod 14 by the pin 16,
can rotate about the pin 16 of the fixed rod 14 as a fulcrum. In this state, if the operating lever 21 is tilted forward, the rod 20, bell crank 19, rod 18, lever 15, and rod 22
moves in the direction of the arrow, the switching valve 25 switches to the left, the oil in the hydraulic pump 26 flows in the direction of the arrow, the travel motor 24 rotates forward, and the lower traveling body 1 moves in the direction in which the control lever 21 is operated.

Next, when the swivel base 2 faces backwards, that is, when the swivel base 2 turns more than 90 degrees left and right from the front position, the limit switch 4 at the bottom of the swivel base 2
engages with the cam 3 on the upper part of the lower running body 1 and turns ON. Solenoid valve 6 switches to the left, air source 5
Air enters the right chamber of air cylinder 7,
The piston rods 10, 10' move to the left, the right fork end 11 no longer fixes the fixed rod 14, and instead the left fork end 11'
presses and fixes the fixing rod 14' against the side surface of the hole 13'. Therefore, the lever 15 is connected to the fixed rod 1.
It rotates about the pin 16' at the tip of 4' as a fulcrum. When the operating lever 21 is pushed forward (backwards with respect to the lower traveling body 1), the lever 15 is moved to the pin 1 via the rod 20, bell crank 19, and rod 18.
Rotates in the same direction as the rod 18 using 6' as a fulcrum,
The switching valve 25 is switched to the right via the rod 22. The traveling motor 24 rotates in the opposite direction to that described above, and the lower traveling body 1 moves backward, that is, in the driver's eyes, in the direction in which the operating lever 21 is depressed.

In addition, the lever 15 has fixed rods 14, 14',
pins 16, 16' connecting rods 18, 22;
The positions of 17 and 23 are such that pins 17 and 16' are at both ends,
Pin 23 is from the center, pin 16 is from the center to pin 17
As mentioned above, the position is 1/3 of the length away from the pin 16', but this means that even if either pin 16 or 16' becomes the fulcrum, the ratio of the amount of movement of pin 23 and pin 17 is Although it is intended to be 1:2, it is not necessarily limited to this, and the pin 23 is located inside the pins 16, 16', the pin 17 is located outside, and the pin 23 and the pin 17 There is no problem as long as the ratio of the distance from to pin 16 or pin 16' is the same.

As mentioned above, this invention allows the driver to operate the operating lever without worrying about the direction of the swivel base, regardless of whether the swivel base is facing forward or backward, and the undercarriage will move. Since it moves in that direction, it is not only easy to operate, but there is no need to consider the operating direction of the operating lever and the moving direction of the vehicle body when working in a narrow space or loading onto a trailer etc. for transportation. Therefore, it is easy to operate, and
It's safe.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention; Fig. 1 is a schematic explanatory diagram, Fig. 2 is a sectional view AA of Fig. 1, Fig. 3 is an explanatory diagram of the operation system, and Fig. 4 is a view from B in Fig. 1. Figure,
FIG. 5 is a CC sectional view of FIG. 4, and FIGS. 6 and 7 are illustrations of the operating principle. DESCRIPTION OF SYMBOLS 1... Lower running body, 2... Swivel base, 3... Cam, 4... Limit switch, 6... Solenoid valve, 11... Fork end, 14... Fixed rod, 15... Lever, 18... Rod , 21...
Operation lever, 22...rod, 24...travel motor, 25...switching valve.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) A semi-circular cam is provided on the undercarriage of a rotating working vehicle having a rotating platform, concentric with the center of rotation of the rotating platform, and the said rotating platform can be rotated by more than 90 degrees left and right. In the traveling device, the direction of pressure oil supply to the traveling motor is switched between forward and reverse based on the engagement with the cam when the cam is engaged with the cam. A lever 15 having a selective fulcrum is provided, and in order to selectively fix the lever 15, a piston rod 1 is provided.
Fork end 1 at the tip of each of 0 and 10'
A double rod type air cylinder 7 having cylinders 1 and 11' and two brackets 12 and 12' are provided on the swivel base 2, and the two brackets 12, 12' are
Fixing rods 1 are inserted into holes 13 and 13' of 12', respectively.
4 and 14' respectively, and on the other hand, a limit switch 4 is provided to detect the position of the cam 3 of the lower traveling body 1, and a solenoid valve 6 is provided to switch the supply direction of the air cylinder 7 by an electric signal from the limit switch 4. and the fork end 11 is activated by the operation of the air cylinder 7.
or 11' to press the fixing rod 14 or 14' into the hole 13 or 13' of the bracket so that the fixing rod 14, 14' can be fixed;
A steering device for a turning work vehicle characterized in that a rod 18 leading to an operating lever 21 and a rod 22 leading to a travel motor switching valve 25 are connected via a lever 15. (2) In the lever 15 according to claim 1, the ratio of the distance from the fixed rod 14' to the rod 22 for the switching valve 25 and the distance from the fixed rod 14' to the rod 18 on the operating lever 21 side is the same as that for the switching valve 25. A swing work vehicle characterized in that the ratio of the distance from the valve 25 rod 22 to the fixed rod 14 and the distance from the fixed rod 14 to the operating lever 21 side rod 18 is set to be the same. Steering device.