JPH0224375Y2 - - Google Patents

Description

[Detailed Description of the Invention] <Technical Field> The present invention relates to a steering device for a vehicle with a liftable cab such as a picking forklift.

<Prior Art> A conventional steering device was constructed as shown in FIGS. 2 and 3. That is, a driver's cab A having a steering handle 1, and an elevating mast B that guides the driver's cab A up and down.
and a fixed mast C that guides the lifting mast B up and down.
, a chassis D supporting the fixed mast C, and the chassis D
A steering device comprising a switching wheel 2 (drive front wheel) mounted on a steering wheel, a drive unit E thereof, and a transmission device F that transmits operating force between the steering handle 1 and switching wheel 2. In a platform elevating vehicle, a reduction gear 21 directly connected to the steering handle 1
an input gear 22, a reduction sprocket 24 directly connected to the output gear 23, a pair of first pulleys 4 supported on the driver's cab A, and a pair of A second pulley 5, a pair of third pulleys 6 supported on the lower part of the fixed mast C, a sprocket 25 supported on the chassis D, a reduction sprocket 24, first, second, third pulleys 4, 5, 6, chains 26 and 27 fixed to both ends thereof and engaged with sprockets 24 and 25, and a transmission mechanism G for transmitting rotation of the sprocket 25 to the switching wheel 2. ing. The transmission mechanism G includes a shaft 10 fixed to a sprocket 25, a sprocket 11 fixed to this shaft 10, and a sprocket 11 fixed to the sprocket 25.
an endless chain 12 engaged with the chain 12, a sprocket 13 engaged with the chain 12, a shaft 14 fixed to the sprocket 13, a small gear 15 fixed to the shaft 14, and a sprocket 13 engaged with the gear 15. It is composed of a large gear 16 and a pivot shaft 17 that rotatably supports a drive unit E, which is a support for the switching wheel 2 and has the gear 16, on a chassis D.

However, in this configuration, since the reduction gear 21 is directly connected to the steering handle 1, the steering wheel operating force is transmitted to the reduction sprocket 24 in an amplified state, and this amplified force is transmitted to the transmission cable 20 and the chains 26, 2.
7, a large tension is applied to the transmission cable 20, and since the stroke L of the chain 27 is limited by the position of the sprocket 25 and the third pulley 6, the turning angle of the switching wheel 2 is also limited. There are drawbacks.

<Purpose> The present invention was made to eliminate the above-mentioned drawbacks, and its purpose is to provide an operating device that reduces the tension applied to the power transmission cable, increases its durability, and allows the turning angle of the switching wheel to be increased. .

<Embodiment> Hereinafter, an embodiment of the present invention will be explained with reference to FIGS. A fixed mast C that guides the mast B up and down, a chassis D that supports the fixed mast C, a switching wheel 2 (drive front wheel) mounted on the chassis D and its drive unit E, the steering handle 1 and the switching wheel. In a driver's cab elevating type vehicle equipped with a steering device consisting of a transmission device F that transmits operating force between steering wheels 2, a small-diameter sprocket 3 directly connected to the steering handle 1 and a small-diameter sprocket 3 supported on the driver's cab A. a pair of first pulleys 4, a pair of second pulleys 5 supported one by one on the upper part of each of the left and right lifting masts B, or a pair of second pulleys 5 supported on either one of the left and right masts B, and a fixed mast. A pair of third pulleys 6 supported on the lower part of the drive unit E and a large diameter reduction pulley 7 supported on the chassis D separately from the drive unit E are provided, and a chain 8 engaged with the small diameter sprocket 3 is provided. and a pair of power transmission cables 9, one end 9a of which is fixed to both ends of the chain 8, and the other ends 9b, 9c are fixed to the deceleration pulley 7 in a winding state, and the deceleration pulley 7.
A transmission mechanism G is provided for transmitting the rotation of the wheel to the switching wheel 2.

The transmission mechanism G includes a shaft 10 fixed to the reduction pulley 7, a sprocket 11 fixed to the shaft 10, an endless chain 12 engaged with the sprocket 11, and an endless chain 12 engaged with the chain 12. sprocket 13 and sprocket 13
a shaft 14 fixed to the shaft 14, a small gear 15 fixed to the shaft 14, and a large gear 1 engaged with the gear 15.
6, and a pivot shaft 17 that rotatably supports a drive unit E, which is a support for the switching wheel 2 and has the gear 16, on the chassis D.

In the above, when the steering handle 1 is rotated, the operating force is directly transmitted to the small-diameter sprocket 3, chain 8, and transmission cable 9, causing the large-diameter deceleration pulley 7 to rotate in a decelerated state. And that axis 10
is rotated by amplified operating force (torque),
The switching wheel 2 is switched via the transmission mechanism G. Note that if the deceleration pulley 7 rotates more than one revolution during the changeover, the groove width of the deceleration pulley 7 should be increased to prevent the pair of transmission cables 9 from overlapping each other as shown in the figure, or the spiral guide It is sufficient to form a groove.

<Effects> As is clear from the above explanation, the present invention consists of a small-diameter sprocket directly connected to the steering wheel, a pair of first pulleys supported on the driver's cab, and a pair of first pulleys supported on the top of the lifting mast. a second pulley; a pair of third pulleys supported at the bottom of the fixed mast;
A large diameter reduction pulley supported by the chassis is provided, a chain engaged with the small diameter sprocket, one end fixed to each end of the chain, and the other end fixed to the reduction pulley in a wrapped state. A pair of transmission cables attached thereto and a transmission mechanism that transmits the rotation of the deceleration pulley to the switching wheel are provided.

Therefore, according to the present invention, the operating force of the steering handle is directly transmitted to the transmission cable without being amplified, so that the tension applied to the transmission cable is reduced and its durability is increased.

Moreover, since the transmission cable can rotate regardless of the dimension between the deceleration pulley and the third pulley, the turning angle of the switching wheel can be increased.

Furthermore, since the deceleration pulley is provided separately from the drive unit, the drive unit can be made smaller, which has the advantage of not being limited by installation space.

[Brief explanation of the drawing]

FIG. 1 is a schematic perspective view of a steering device according to an embodiment of the present invention, FIG. 2 is a perspective view of a single-portable cab lift vehicle, and FIG. 3 is a schematic perspective view of a conventional steering device. 1... Steering handle, A... Cab, B... Lifting mast, C... Fixed mast, D... Chassis, 2...
...Direction wheel, E...Drive unit, F...Transmission device, 3...Small diameter sprocket, 4...First pulley, 5...Second pulley, 6...Third pulley, 7
...Large diameter reduction pulley, 8...Chain, 9...Transmission cable, G...Transmission mechanism.

Claims (1)

[Scope of utility model registration request] A driver's cab having a steering handle, a lifting mast that guides the driver's cab up and down, a fixed mast that guides the lifting mast up and down, a chassis that supports the fixed mast, a switching wheel attached to the chassis, and In a cab-elevating vehicle equipped with a drive unit and a steering device consisting of a transmission device that transmits operating force between the steering handle and the switching wheels, a small-diameter sprocket directly connected to the steering handle; , a pair of first pulleys supported on the driver's cab, a pair of second pulleys supported on the upper part of the lifting mast, a pair of third pulleys supported on the lower part of the fixed mast, and the drive unit. Separately, a large-diameter reduction pulley supported by the chassis is provided, and a chain is engaged with the small-diameter sprocket, and one end is fixed to each end of the chain, and the other end is wound around the chain. 1. A steering device for a vehicle with an elevator cab, characterized in that a pair of transmission cables are fixed to a reduction pulley, and a transmission mechanism that transmits the rotation of the reduction pulley to a switching wheel.