JPH0751974Y2 - Trolley steering device - Google Patents

Description

[Detailed Description of the Invention] [Industrial field of application] The present invention relates to a vehicle for supporting a heavy object such as a blade of an airplane by a hydraulic jack or the like mounted on the vehicle to move the vehicle to a predetermined position. The present invention relates to a steering device.

[Conventional technology]

For example, as a hydraulic jack that supports heavy objects such as the wings of an airplane, the main body of the truck is erected on the base of the truck so that it can expand and contract vertically, and casters and handles are provided at the ends of the base. There has been developed a method of moving a cart to an arbitrary position by selecting a traveling direction of a cart while operating a direction of a caster with a handle.

That is, in the above, the handle is operated to transfer the dolly to the lower part of the heavy object, in this state, the hydraulic jack mounted on the base is extended, and the heavy object is transferred while being supported by the ram of the hydraulic jack. It is a thing.

[Problems to be solved by the device]

As described above, the conventional truck for a hydraulic jack described above requires a large force to operate the handle because the handle is manually operated to move the cart straight or turn, and in particular, it is mounted on the truck. When the hydraulic jack body, the hydraulic unit, the operation panel, and the like are large, the dolly itself becomes heavy, and it becomes difficult to operate the handle manually.

Moreover, since the steering operation must be performed manually by the operator while pushing and pulling the trolley with the handle, the steering and width-shifting operations are difficult, and the handle operation is particularly heavy. In some cases, stationary operation cannot be performed.

Therefore, an object of the present invention is to provide a trolley steering device capable of easily and smoothly operating a handle even with a heavy trolley, and facilitating turning, width adjustment, and stationary operation.

[Means for Solving the Problems]

According to the present invention, the above-mentioned object is to mount a caster on the end of the base of the carriage and select the traveling direction of the carriage while moving the direction of the caster with the handle to move it to an arbitrary position. In the dolly, the casters are connected to the base by the steering cylinders arranged symmetrically, and these steering cylinders are connected to the pump and the tank through solenoid switching valves, respectively, while the handle is rotatably connected to the casters in the operating direction. In addition, a limit switch for detecting the steering direction of the steering wheel and a limit switch for detecting the steering direction of the casters are provided respectively, and signals from these limit switches are used to select the solenoid switching valve and its switching direction. And keep one steering cylinder free. The square of the steering cylinder by expansion and contraction in a predetermined direction is achieved by to perform the steering of the caster.

[Action]

That is, as long as the caster is steered in one direction from the straight traveling state, the steering direction of the caster is detected by the limit switch for it, and when the handle is operated, the operating direction is the same as that of the steering wheel. Detected by limit switch.

Therefore, if you operate the steering wheel regardless of whether it is stopped or running and turn the caster slightly in either direction, the steering direction and the steering direction of the caster at this time are detected simultaneously by the respective limit switches. The signals from these limit switches are used to select the solenoid switching valve and the switching direction of the selected solenoid switching valve.

As a result, only the selected solenoid switching valve switches to the predetermined direction and the steering cylinder on that side expands and contracts while keeping the steering cylinder on that side in the free state while keeping the solenoid switching valve not selected. While the steering cylinder assists the steering wheel operation, the caster turns in accordance with the steering wheel operating direction, which reduces the steering wheel operation.

〔Example〕

Hereinafter, an example of a preferred embodiment of the present invention will be described with reference to the accompanying drawings.

The dolly 1 includes a base 2, a hydraulic jack body 9 that stands up from the center of the base 2 and extends and contracts in the vertical direction, and three telescopic legs 3 attached to the upper part of the hydraulic jack body 9.
4, 5 and a lift cylinder 18 attached to the end of the base 2 via a bracket 17, a caster 19 attached to a ram 18 'of the lift cylinder 18 via a bracket 6', and one end of the bracket 16 '. It has a handle 6 attached at the attachment portion 20.

An operation panel 7 and a hydraulic unit 8 are mounted on the base 2, and a platform 10 is mounted on the hydraulic jack body 9.

Each leg 3,4,5 has stays 11,12, and these legs 3,4,5
It is placed on the slide portion 16 provided on the base 2 via the brackets attached to the bases 4 and 5, and the lower end extends in the ground direction through the openings 13, 14, 15 provided on the base 2. .

When the trolley 1 moves, these legs 3, 4, 5 are compressed and the lower ends are lifted from the ground. When the hydraulic jack body 9 extends to support a heavy object, these legs 3, 4, 5 are extended. The lower end of each is lowered to the ground, and the legs 3, 4, and 5 carry heavy objects to stabilize the trolley 1.

As described above, the caster 19 attached to the ram 18 'of the lift cylinder 18 via the bracket 6', and the handle 6 attached to the one end of the bracket 6'with the attachment portion 20 are the ram 18 around the axis of the lift cylinder 18. 'And bracket 6'
It is possible to rotate integrally through.

The caster 19 is rotatably driven by the drive motor 21 provided on the bracket 6 ', and the handle 6 is
It is movably connected to the bracket 6'with a mounting portion 20 in a predetermined range in the operation direction.

Further, one end of the base 2 is lifted upward by extending the lift cylinder 18, so that the supporting leg (not shown) provided at the end of the base 2 can be lifted from the ground. There is.

At the end of the base 2 are two steering cylinders 22, 23.
Of the steering cylinders 22 and 23 are pivotally attached to the bracket 6'through a common shaft 24.

Limit switches L on both sides of bracket 6 '
S ₁ and LS ₂ are provided and face the horizontal arm portion of the handle 6.

The central portion of the horizontal arm portion of the handle 6, the limit switch LS ₃ is shifted to the upper and lower stages, LS ₄ is is provided with, these limit switches LS _3, LS ₄ is upper and lower stages on the outer surface of the lift cylinders 18 The projections 25 and 26 provided on the base plate are in contact with each other (see FIG. 3).

As shown in FIG. 4, each steering cylinder 22, 23 has an oil chamber A, B, and each oil chamber A, B has a solenoid switching valve 2
It communicates with pump P and tank T via 7,28.

In the neutral state, the solenoid switching valves 27, 28 connect the oil chambers A, B to the tank T so that the steering cylinders 22, 23
Is maintained in a free state, and the steering cylinders 22 and 23 are selectively expanded and contracted in accordance with the switching direction.

As described above, when the handle 6 is operated to the left or right with respect to the bracket 6'and the limit switch LS ₁ or LS ₂ is turned ON, _{one of} the solenoid switching valves 27 and 28 is switched correspondingly, and the steering cylinder 22 Or 23
Expands and contracts to turn the caster 19 by following the operating direction of the handle 6 via the bracket 6 '.

When the caster 19 turns, the limit switch LS ₃ or LS ₄ provided at the center of the horizontal portion of the handle 6 is turned on by the protrusion 25 or 26 provided on the lift cylinder 18.

As a result, as shown in FIG. 5, for example, if the caster 19 turns to the right and the limit switch LS ₄ is turned on by the protrusion 26 on the lift cylinder 18 and the handle 6 is operated to the right, the limit switch LS Limit switch L with ₄
When S ₂ is turned on, the solenoid switching valve 27 is switched to the extension side, and the steering cylinder 22 operates toward the extension side while keeping the steering cylinder 23 in the free state, and the caster 19 is further turned to the right.

On the contrary, if the handle 6 is operated to the left, this time the limit switch LS ₄ and the limit switch LS ₁ are turned on, the solenoid switching valve 27 is switched to the compression side, and the steering cylinder 23 is kept free. As it is, the steering cylinder 22 moves toward the compression side to return the caster 19 to the left.

Similarly, the caster 19 turns to the left and the limit switch
When LS ₃ it is assumed that the handle 6 to the left in a state of being ON by the protrusion 25 of the lift cylinder 18 side, a limit switch LS
₃ , the limit switch LS ₁ is turned on and the solenoid switching valve 28 is switched to the extension side this time, and the steering cylinder 23 moves to the extension side while keeping the steering cylinder 22 in the free state, and the caster 19 is further left. Turn to the direction.

On the contrary, if the steering wheel 6 is operated to the right, the limit switch LS ₃ and the limit switch LS ₂ are turned on, the solenoid switching valve 28 is switched to the compression side, and the steering cylinder 22 is kept in the free state. The cylinder 23 moves toward the compression side and returns the caster 19 to the right.

When the casters 19 are in the straight running state and the limit switches LS ₃ and LS ₄ are not in contact with the protrusions 25 and 26 on the lift cylinder 18, the handle 6 is operated to turn the limit switches LS ₁ and LS ₂ ON. Even if this happens, the solenoid switching valves 27, 28 are kept in the neutral position without being switched between the extension side and the compression side, and the steering cylinders 22, 23 remain free.

Table 1 below shows the operation relationship between the limit switches LS ₁ , LS ₂ , LS ₃ , LS ₄ and the steering cylinders 22, 23.

[Effect of the Invention] As described above, the steering device for a bogie according to the present invention can exhibit the following effects.

When the steering wheel is operated, the steering cylinder, which is a power cylinder, automatically expands and contracts, and the casters are turned in response to this, which makes the steering wheel operation lighter, and it is easy to turn even a large or heavy truck. it can.

Since the steering operation is light and easy, it is possible to perform fine adjustment operations such as turning and width adjustment of the bogie.

 The stationary operation can be lightened.

 Steering operation can be performed efficiently and quickly.

[Brief description of drawings]

FIG. 1 is a plan view of a truck equipped with a steering device according to the present invention, FIG. 2 is an enlarged front view of a handle portion of FIG. 1, and FIG. 3 is a limit switch for detecting a steering direction of a caster. FIG. 4 is an enlarged schematic view showing the operating portion, FIG. 4 is an explanatory view showing the relationship between the steering cylinder and the limit switch in principle, and FIG. 5 is a partially enlarged plan view showing the operating state when the steering wheel is operated. 1 ... Car, 2 ... Base, 6 ... Handle, 6 '... Bracket, 9 ... Hydraulic jack body, 19 ... Caster, 22,23 ... Steering cylinder, 27,28 ... Solenoid switching valve , P ... Pump, T ... Tank, LS ₁ , L
S ₂ , LS ₃ , LS ₄ ... Limit switch.

Claims (1)

[Scope of utility model registration request] 1. A trolley in which a caster is attached to an end of a pedestal of the trolley, and the trolley is moved to an arbitrary position by selecting a traveling direction of the trolley while operating a direction of the caster with a handle, The steering cylinders that are arranged symmetrically are connected to the base, and these steering cylinders are connected to the pump and tank through solenoid switching valves, respectively, while the handle is connected to the casters so as to be rotatable in the operating direction, and A limit switch for detecting the operating direction and a limit switch for detecting the turning direction of the casters are provided respectively, and a signal from these limit switches is used to select the solenoid switching valve and its switching direction, and The other steering cylinder while keeping the cylinder free. Truck steering apparatus characterized by a by expansion and contraction in a predetermined direction performing steering of the caster.