JP2001261294A - Forklift - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a forklift furnished with a torque transmission mechanism constituted with a small number of parts, to facilitate assembly work and free to reduce a trouble of maintenance work concerning inspection and tensile force adjustment. SOLUTION: A forklift 1 is provided with a trorque transmission mechanism 2, and the torque transmission mechanism 2 is furnished with toothed pulleys 3, 4 respectively connected to a handle shaft 56a of a handle 56 for steering and an input shaft of a torque detector 55, pulley cases 5, 6 to inner-package each of the toothed pulleys 3, 4 and to support them free to rotate, a toothed inner cable 7 suspended between the toothed pulleys 3, 4 and to travel and outer casings 8, 8 arranged in parallel between the pulley cases 5, 6 while guiding the toothed inner cable 7 free to travel by inner-packaging it and free to bend.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a forklift, and more particularly, to a structure of a torque transmission mechanism provided between a torque detector and a steering handle provided in a power steering device.

[0002]

2. Description of the Related Art In recent forklifts, a battery has been used as a drive source instead of an internal combustion engine because of the need to preserve the surrounding environment. Some include an electric power steering device for improvement. As an example of such a forklift, a battery type three-wheel forklift disclosed in Japanese Patent Publication No. 2857518 is known, and this forklift has a configuration schematically shown in FIG.

That is, a forklift 51 shown in FIG.
Is provided on an electric power steering device 54 that steers a rear wheel 53 located at the rear of a vehicle body 52 in which a relatively large battery (not shown) is installed under a seat, and steers the rear wheel 53. A torque transmission mechanism 57 having a chain hooking structure for transmitting a steering torque is provided between the torque detector 55 and a steering handle 56 located at a front part of the vehicle body 52.

[0004]

By the way, the forklift according to the conventional form has a torque transmitting mechanism 57.
Is constructed by employing a multi-stage chain hanging structure, so that the following inconvenience is caused. That is, the steering wheel 56 located at the front of the vehicle body 52 while avoiding a relatively large battery under the seat.
A torque transmission mechanism 57 must be provided from the rear to the rear wheel 53, which is a steering wheel located at the rear of the vehicle body 52, and this torque transmission mechanism 57 is complicated. As a result, the number of parts increases, and the assembling work tends to be complicated.

SUMMARY OF THE INVENTION The present invention has been made in order to solve various inconveniences caused by the configuration in which the torque transmission mechanism employs a chain hanging structure, and can simplify the transmission mechanism and reduce the number of parts. It is an object of the present invention to provide a forklift including a torque transmission mechanism that can easily perform an assembling operation and can also reduce the time and labor for maintenance work related to inspection and tension adjustment.

[0006]

SUMMARY OF THE INVENTION A forklift according to the present invention includes a power steering device,
A torque transmission mechanism is provided between a torque detector included in the power steering device and a steering handle. The torque transmission mechanism is provided between a handle shaft of the steering handle and an input shaft of the torque detector. Toothed pulleys connected to each other, a pulley case that rotatably supports each of the toothed pulleys, a toothed inner cable that runs across the toothed pulley, and a toothed inner cable A flexible outer casing which is arranged in parallel between the pulley cases while being guided inside and traveling freely.

[0007] The toothed inner cable at this time is preferably a geared wire, and the toothed pulley is preferably a pulley for a geared wire, and a length adjusting mechanism is provided at an intermediate position along the longitudinal direction of the outer casing. Is desirably provided. With the above-described configuration, the torque transmission mechanism is not a chain hanging structure but a cable hanging structure, so that the transmission mechanism is easy to simplify, the number of parts is small, the assembly work is easy, and inspection and adjustment are easy. The advantage that it is possible to greatly reduce the labor of the related maintenance work is secured.

[0008]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a structural explanatory view schematically showing the entire configuration of a forklift according to the present embodiment, and FIG.
FIG. 3 is a structural explanatory view showing a simplified structure of the torque transmission mechanism according to the present embodiment. FIGS. 3 and 4 are cross-sectional views of the inner cable and the outer casing of the torque transmission mechanism according to the present embodiment. FIG. 3 is a structural explanatory view showing a surface configuration. In addition, since the entire configuration itself of the forklift according to the present embodiment is not fundamentally different from the conventional embodiment, the same components as those in FIG.
The same reference numerals are given to the portions, and the detailed description is omitted here.

The forklift according to the present embodiment is a battery-type three-wheel forklift having the same configuration as that of the related art. As shown in FIG.
A rear wheel 53 located at a rear portion of the vehicle body 52 on which a battery (not shown) is installed is used as a steering wheel, and a torque detector 55 provided in an electric power steering device 54 for steering the rear wheel 53 and a vehicle body 52 The torque transmission mechanism 2 is provided between the steering wheel 56 and the steering wheel 56 located at the front of the vehicle. In this case, the electric power steering device 54 includes a torque detector 55, a controller (not shown), a steering motor 58, and a steering mechanism 59, as in the related art.

Further, the torque transmission mechanism 2 here is shown in FIG.
As shown in FIG. 2, a pair of toothed pulleys 3, 4 connected to the handle shaft 56a of the steering handle 56 and the input shaft of the torque detector 55, respectively, And a pulley case 5 and 6 that rotatably support each of the pulleys, a toothed inner cable 7 that is bridged between the toothed pulleys 3 and 4 to transmit steering torque while traveling, and a toothed inner cable The inner casing 7 is provided with flexible outer casings 8, 8 arranged in parallel between the pulley cases 5, 6 while being guided while traveling freely.

The toothed inner cable 7 is S
A geared wire whose terminals are connected by using a nipple end 9 made of 35C, that is, a strand 7a made of SUS304 as shown in a cross-sectional configuration in FIG.
Is a ring-shaped geared wire in which a SUS304 coil 7b is wound at a predetermined pitch along the outer periphery of
Toothed pulley 3 made of PHC or SS400
Although not shown in the figure, a plurality of grooves, which are not shown, are formed at a predetermined pitch on the outer peripheral end face of the outer peripheral end face so as to be engaged with the coil 7b of the geared wire which is the toothed inner cable 7. The toothed inner cable 7 is not limited to a geared wire, but may be a more general toothed belt or the like.

On the other hand, each of the outer casings 8 and 8 has a hollow liner 8a made of POM through which the toothed inner cable 7 is inserted and guided, as shown in a cross-sectional configuration in FIG. SWO-A shield 8b disposed along the longitudinal direction of the outer periphery
And a coat 8c made of PP, which covers the outer periphery of the hollow liner 8a including these shields 8b. And the bridged toothed pulley 3,
Each of the outer casings 8, which have a strength in the longitudinal direction to maintain the overall length against the tension of the inner cable 7 running between the four and which can be bent along a direction intersecting the longitudinal direction, is shown in FIG. As shown in the figure, the ZDC2 is arranged between the pulley cases 5 and 6 after being bent while being juxtaposed with each other.

By the way, the pulley cases 5, 6 at this time, that is, the pulley cases 5, 6 in which the toothed pulleys 3, 4 are housed, are attracted by the inner cable 7 to which tension acts. Outer casing 8, which is arranged in parallel between cases 5 and 6,
Since it is impossible for each of the pulley cases 8 to come off from the pulley cases 5, 6, it is not necessary to fixedly attach the outer casings 8, 8 to each of the pulley cases 5, 6. Then, the outer casing 8, which is bent and arranged to correspond to the equipment layout,
8, the inner cable 7 is guided, and the inner cable 7 is connected to the outer casing 8,
8 while traveling.

That is, the torque transmission mechanism 2 according to the present embodiment is provided between the torque detector 55 and the steering handle 56 after having the above-described structure. Pulley case 5 with 4 inside
A pair of outer casings 8 arranged in parallel between
8 is arranged along the vehicle body 2 in an arbitrary bent state. Therefore, the inner cable 7 bridged between the toothed pulleys 3 and 4 travels while being guided by the outer casings 8 and 8 that are bent and arranged. The steering torque applied from the toothed pulley 3 connected to the handle shaft 56a of the steering handle 56 is transmitted to the toothed pulley 4 connected to the input shaft of the torque detector 55.

Therefore, the steering motor 58 is driven to rotate in response to the signal output from the controller in accordance with the steering torque detected by the torque detector 55, and the torque of the steering motor 58 is reduced by the steering mechanism. As a result of being added after being decelerated via 59, the rear wheel 53, which is a steered wheel, is steered. A lubricant such as grease may be sealed inside the outer casings 8, 8, and when the lubricant is sealed, the running state of the inner cable 7 is improved and torque transmission is performed. The advantage that the service life of the mechanism 2 is increased is secured.

Further, a length adjusting mechanism 10 for changing the total length of the outer casings 8, 8 is provided at a halfway position along the longitudinal direction of one of the outer casings 8. The mechanism 10, as shown in FIG.
A screw 11 and a nut 12, each of which has one end fitted to the intermediate end of the outer casing 8 and the other end screwed together, and the screw 11 and the screw 11 interposed therebetween. A pair of lock nuts 1
3, 13, a spring washer 14, and a buffer spring 15 interposed between an inner protrusion of the nut 12 and an intermediate end of the outer casing 8. The screw 11 and the nut 12 here are SS40
0 or S35C, lock nut 13 is SS400
The spring washer 14 is made of SWRH4, and the spring 15 is made of SWPA.

That is, one outer casing 8
The length adjustment mechanism 10 provided in the screwdriver 11 is capable of changing the entire length of the outer casing 8 by changing the position where the screw 11 and the nut 12 are screwed with each other. The mating position is maintained by the lock nuts 13,13. When such a length adjusting mechanism 10 is provided for the outer casing 8, the tension acting on the inner cable 7 running inside the outer casings 8, 8 changes over time. Even if the entire length of the inner cable 7 expands and contracts, it is possible to cope with the expansion and contraction of the inner cable 7 by changing the entire length of the outer casing 8 by the length adjusting mechanism 10.

In this embodiment, the forklift 1 provided with the torque transmitting mechanism 2 is a battery-type three-wheel forklift similar to the conventional one. However, other forklifts, for example, a horizontal sitting reach three-wheel forklift, Of course, it may be a four-wheeled forklift. Further, in the forklift 1 according to the present embodiment, the rear wheels 53 are the steered wheels, but the present invention is not limited to such a configuration, and the front wheels 16 located at the front part of the vehicle body 52 may be the steered wheels. Further, the materials of the various components constituting the torque transmission mechanism 2 are not limited to those described above, and it is a matter of course that components having optimum materials are selected as needed. Furthermore, the present invention is not limited to the electric power steering device, but can be applied to a hydraulic power steering device.

[0019]

As described above, the torque transmission mechanism provided in the forklift according to the present invention includes a toothed pulley connected to each of the handle shaft of the steering handle and the input shaft of the torque detector. A pulley case that rotatably supports each of the toothed pulleys, a toothed inner cable that runs across the toothed pulleys, and a pulley that contains the toothed inner cables and guides them to run freely Since it is configured with a flexible outer casing arranged in parallel between the cases, the number of parts is greatly reduced as compared with the conventional configuration, and the assembling work is easy. At the same time, it is possible to reduce the time and effort required for daily inspection.

Further, according to the present invention, a length adjusting mechanism is provided at an intermediate position along the longitudinal direction of the outer casing which guides the inner casing with the toothed inner cable so as to be able to travel freely. The total length of the inner cable can be changed by expanding and contracting the entire length of the outer casing, and the change in tension can be accommodated by the change in expansion and contraction of the inner cable. The effect that the labor of the work can be greatly reduced is also ensured.

[Brief description of the drawings]

FIG. 1 is a structural explanatory diagram schematically showing an overall configuration of a forklift according to the present embodiment.

FIG. 2 is a structural explanatory view showing a simplified overall configuration of a torque transmission mechanism according to the present embodiment.

FIG. 3 is a structural explanatory view showing a cross-sectional configuration of an inner cable included in the torque transmission mechanism according to the present embodiment.

FIG. 4 is a structural explanatory view showing a cross-sectional configuration of an outer casing provided in the torque transmission mechanism according to the present embodiment.

FIG. 5 is a structural explanatory view schematically showing the entire configuration of a forklift according to a conventional embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Forklift 2 Torque transmission mechanism 3 Toothed pulley 4 Toothed pulley 5 Pulley case 6 Pulley case 7 Inner cable 8 Outer casing 55 Torque detector 56 Steering handle 56a Handle shaft

Claims (3)

[Claims] 1. A power steering device, comprising:
What is claimed is: 1. A forklift having a torque transmission mechanism provided between a torque detector provided in a power steering device and a steering handle, wherein the torque transmission mechanism includes a steering shaft of the steering handle and an input of the torque detector. A toothed pulley connected to each of the shafts, a pulley case that houses each of the toothed pulleys and rotatably supports them, a toothed inner cable that runs across the toothed pulleys, and a toothed A forklift, comprising: a bendable outer casing disposed between pulley cases while guiding an inner cable so that the inner cable can travel freely. 2. The forklift according to claim 1, wherein the toothed inner cable is a geared wire, and each of the toothed pulleys is a pulley for a geared wire. 3. The forklift according to claim 1, wherein a length adjustment mechanism is provided at an intermediate position along a longitudinal direction of the outer casing.