JP3250487B2 - Reach type forklift - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reach-type forklift, and more particularly to a reach-type forklift driven by front wheels.

[0002]

2. Description of the Related Art In a rear-wheel drive forklift, when a load is applied to a fork, the load applied to the rear wheels is reduced, and there is a possibility that a sufficient driving force cannot be obtained on a floor surface where slippage is likely to occur. is there. Therefore, forklifts that attempt to effectively prevent slippage when starting by driving the front wheels have been put to practical use.

FIG. 5 shows a front wheel portion of a conventional reach-type forklift in which the front wheels are driven. The front wheel 2 is attached to the front end of the reach leg 1 formed to extend in front of the machine base.
A motor 4 is connected to the front wheel 2 via a speed reducer 3. The speed reducer 3 includes a helical gear 5 fixed to the front wheel 2, helical gears 6 and 7 that sequentially mesh with the helical gear 5, a ring gear 8 integrally formed with the helical gear 7, and a gear 4 that meshes with the ring gear 8 and drives the motor 4. And a pinion gear 9 attached to the shaft.

A pair of such reach legs 1 is provided in parallel with each other, and a reach rail 10 for guiding the mast in the front-rear direction is disposed inside the reach legs 1. For this reason, although the reduction gear 3 and the motor 4 are housed inside the reach leg 1, the motor 4 is housed in the narrow reach leg 1.
So that its drive shaft faces the length direction of the reach leg 1,
That is, they are arranged in a direction orthogonal to the rotation axis of the front wheel 2. Therefore, a pinion gear 9 is fitted to the drive shaft, and the ring gear 8 is meshed with the pinion gear 9 to transmit the driving force of the motor 4 to the helical gear 7 while bending the driving force at a right angle.

[0005]

However, since the driving force of the motor 4 is transmitted at a right angle to the helical gear 7, the efficiency of the speed reducer 3 is reduced. In addition, since the motor 4 is housed in a narrow space in the reach leg 1, it is difficult to increase the driving force of the front wheel 2 due to the limitation of the physical size of the motor 4. The present invention has been made to solve such a problem, and an object of the present invention is to provide a front-wheel-drive reach-type forklift that is excellent in transmission efficiency of a driving force to a front wheel and can obtain a large driving force. And

[0006]

In a reach type forklift according to the present invention, a mast is provided between a pair of left and right reach legs extending forward of a machine base, and a front wheel is provided at a tip end of the reach leg. In a reach-type forklift, the machine body and the
A pair that guides and supports the chin leg movably in the longitudinal direction of the machine
Guide rail for reach leg and reach leg for rear wheel
To change the wheelbase
Richire in Richiregu and moving reach mechanism, the rear of the mast so that the drive shaft is parallel to the front of the rotation axis for
And a reduction gear for transmitting the driving force of the motor to the front wheels.

Further, the mast may be movably provided along a pair of mast guide rails fixed to the reach leg, and the mast may be moved in the front-rear direction with respect to the reach leg by the action of the mast moving reach cylinder. Good. Alternatively, it is also possible to provide a pant reach device that fixes the mast to the reach leg and supports the fork movably in the front-rear direction with respect to the mast.

[0008]

Embodiments of the present invention will be described below with reference to the accompanying drawings. Embodiment 1 FIG. FIG. 1 shows a reach type forklift according to Embodiment 1 of the present invention. A pair of left and right reach legs 11 extending in the longitudinal direction of the machine base are
Are linked by A front wheel 13 is attached to a front outer portion of each reach leg 11, and a roller 14 is attached to a rear outer portion. A pair of right and left reach leg guide rails 16 are provided on the machine body 15,
Rollers 14 at the rear end of the reach leg 11 are rotatably guided and supported by corresponding guide rails 16. The base plate 12 connecting the left and right reach legs 11
The reach leg 11 is connected to the main body 15 via a reach cylinder 17 for moving the reach leg.
Also, it is configured to be movable in the front-rear direction with respect to the machine body 15.

Each of the pair of reach legs 11 has a guide rail 18 for guiding the mast along the length direction, and a carriage 19 is arranged between the guide rails 18. Rollers 2 are provided on both sides of the carriage 19, respectively.
The rollers 20 are rotatably guided and supported by the guide rails 18 of the corresponding reach legs 11. The carriage 19 has a mast 2
1 is provided substantially upright. This carriage 19
Is connected to the base plate 12 via a reach cylinder 22 for moving the mast, and the carriage 19 is configured to be movable in the front-rear direction with the mast 21 with respect to the reach leg 11 by the action of the reach cylinder 22. The machine body 15 is provided with a rear wheel (not shown).

A motor 23 for driving the front wheels 13 is attached to each reach leg 11. These motors 23 are located behind the position of the mast 21 when the carriage 19 is retracted most rearward by the action of the reach cylinder 22 and between the pair of reach legs 11. Further, the motor 23 is arranged so that its drive shaft is parallel to the rotation axis of the front wheel 13, that is, in the width direction of the machine base. The drive shafts of these motors 23 are connected to the corresponding front wheels 13 via reduction gears 24 provided outside the reach legs 11, respectively.

As shown in FIG. 2, a helical gear 25 is fixed to the front wheel 13 on a rotating shaft, and helical gears 26 and 27 are sequentially meshed with the helical gear 25, and a helical gear 28 formed integrally with the helical gear 27 is formed. It meshes with a helical gear 29 fitted on the drive shaft of the motor 23. The helical gears 25 to 29 form a speed reducer 24. As is apparent from FIG. 2, the drive shaft of the motor 23 to which the helical gear 29 is fitted, the rotation shafts of the helical gears 27 and 28 formed integrally with each other, the rotation shaft of the helical gear 26, and the helical gear 25
The rotation axes of the front wheels 13 to which are fixed are all directed in the width direction of the machine base and are in a mutually parallel relationship. Motor 2
A brake 30 is attached to the back of 3.

Next, the operation of the reach type forklift according to the first embodiment will be described. When the motor 23 is driven, the torque of the drive shaft is increased by the speed reducer 24 and transmitted to the front wheels 13. At this time, since the drive shaft of the motor 23, the rotation shafts of the helical gears 25 to 29 of the reduction gear 24, and the rotation shaft of the front wheel 13 are all arranged in parallel with each other, the driving force of the motor 23 is efficiently transmitted to the front wheel 13. Is done. Therefore, even on a slippery road surface, it is possible to drive the front wheels 13 in a state where the fork is loaded so that the vehicle can travel reliably.

As described above, in the forklift according to the first embodiment, the reach leg 11 can move in the front-rear direction with respect to the machine body 15 and the mast provided on the carriage 19 with respect to the reach leg 11. Reference numeral 21 is configured to be movable in the front-rear direction. FIG. 3A shows a state in which the reach leg 11 is pulled out to the front of the machine body 15 by the action of the reach cylinder 17 and the mast 21 is pulled out to the front of the reach leg 11 by the action of the reach cylinder 22. Show. By pulling the reach leg 11 forward, the front wheel 1
The wheel base between the rear wheel 3 and the rear wheel 31 has a maximum value W1, and the fork 3 is attached to the mast 21 so as to be able to move up and down.
2 is located at the forefront. From this state, when the mast 21 is pulled in to the maximum by the action of the reach cylinder 22,
The result is as shown in FIG. At this time, the wheel base remains at the maximum value W1.

Further, when the reach leg 11 is retracted to the maximum by the action of the reach cylinder 17, the wheel base reaches the minimum value W2 and the mast 21 is retracted along with the reach leg 11, as shown in FIG. 32 is the most retracted state. In this way, the reach leg 11 is retracted to set the wheelbase to the minimum value W2.
Then, the turning radius of the forklift is reduced, and work in a narrow place can be easily performed. In addition, since the front wheel 13 is retracted together with the reach leg 11, the weight applied to the front wheel 13 increases even when there is no load, so that the frictional force between the road surface and the front wheel 13 increases,
A larger driving force can be obtained.

Since the movement of the mast 21 with respect to the reach leg 11 and the movement of the reach leg 11 with respect to the machine body 15 form the entire amount of movement of the fork 32 in the front-rear direction, the reach of the mast 21 with respect to the reach leg 11 can be small. , As shown in FIG.
Even when 1 is pulled to the maximum, a predetermined space is created between the pair of reach legs 11 behind the mast 21. Therefore, in the forklift according to the first embodiment, the motor 23 can be arranged laterally in the space between the pair of reach legs 11 formed behind the mast 21. For this reason, unlike the conventional case where the motor is housed vertically in a narrow space within the reach leg, it is possible to mount the motor 23 having a large size as needed without sacrificing the reach amount.

The motors 23 are mounted on the left and right front wheels 13, respectively. These motors 23 are arranged substantially coaxially with their drive shafts facing in the width direction of the machine base. The left and right front wheels 13 may be configured to be driven using one motor whose drive shafts project in opposite directions from both ends. Further, not only the front wheel 13 but also the rear wheel 31 can be driven to be a front-rear wheel drive type, or the rear wheel 31 can be a drive type in which only the front wheel is not driven.

Embodiment 2 FIG. FIG. 4 shows a reach type forklift according to the second embodiment. This forklift differs from the forklift according to the first embodiment shown in FIG. 1 in that the carriage 19 and the mast moving reach cylinder 22 which are provided movably with respect to the reach leg 11 are omitted, and the mast 21 is fixed to the reach leg 11. Things. The motor 23 for driving the front wheel 13 is mounted on the mast 21 so that its drive shaft is parallel to the rotation axis of the front wheel 13.
And between the pair of reach legs 11. Further, a pant reach device 33 for supporting the fork 32 movably in the front-rear direction is attached to the mast 21 so as to be movable up and down.

Also in the forklift according to the second embodiment, the wheel base can be changed by moving the reach leg 11 in the front-rear direction with respect to the machine body 15 by the action of the reach cylinder 17. The mast 21 is fixed to the reach leg 11, but the fork 32 is supported by the pant reach device 33.
1 can be moved in the front-rear direction.

According to such a configuration, the first embodiment
The same effect as that of the forklift can be obtained. That is,
The motor 23 is arranged so that its drive shaft is parallel to the rotation axis of the front wheel 13, so that the driving force is excellent and the front wheel 13 is driven even on a slippery road surface so that the vehicle can travel reliably. It can be carried out. In addition, reach leg 11
, The turning radius of the forklift is reduced, and the weight applied to the front wheels 13 is increased even when there is no load, so that a greater driving force can be obtained. Further, a motor 23 having a large size can be mounted behind the mast 21 and between the pair of reach legs 11.

In the reach type forklift according to the first and second embodiments, the pair of reach legs 11 is connected to the machine body 1.
5, it is similar to the conventional counter-type battery forklift because it is formed separately.
The components of the speed reducer 24 can be shared, and the components of the machine body 15 can be shared.

[0021]

As described above, according to the present invention, the motor is disposed between the pair of reach legs and behind the mast so that the drive shaft is parallel to the rotation axis of the front wheel, and the motor is arranged via the speed reducer. Since the driving force of the motor is transmitted to the front wheels, the transmission efficiency of the driving force is improved, and a large driving force can be obtained by mounting a large-sized motor. In addition, a pair of reach leg guides fixed to the machine body
Reach leg along the guide rail for
Because it can be moved, the wheelbase becomes variable,
The reduced turning radius of the forklift
Even when empty, the weight added to the front wheels increases,
Greater driving force can be obtained.

[0022]

Further, if the mast is moved in the front-rear direction along a pair of mast guide rails fixed to the reach leg, the fork can be made to reach a large distance depending on the amount of movement of the reach leg and the amount of movement of the mast. it can. Even if the mast is fixed to the reach leg and the fork is supported by the pant reach device so as to be movable in the front-rear direction, the fork is similarly determined by the amount of movement of the reach leg and the amount of movement of the fork by the pant reach device. Can be greatly increased.

[Brief description of the drawings]

FIG. 1 is a partially omitted perspective view showing a reach type forklift according to Embodiment 1 of the present invention.

FIG. 2 is a plan sectional view showing a front wheel portion in the reach type forklift according to the first embodiment.

3A and 3B show the operation of the reach-type forklift according to the first embodiment, in which FIG. 3A is a side view showing a state in which a reach leg and a mast are pulled forward, and FIG. 3B is a side view showing a state in which only the mast is pulled in; (C) is a side view showing a state in which the reach leg and the mast are retracted.

FIG. 4 is a partially omitted perspective view showing a reach type forklift according to a second embodiment.

FIG. 5 is a plan sectional view showing a front wheel portion of a conventional front-wheel drive reach-type forklift.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Reach leg 12 Base plate 13 Front wheel 14, 20 Roller 15 Machine base body 16 Reach leg guide guide rail 17 Reach leg movement reach cylinder 18 Mast guide guide rail 19 Carriage 21 Mast 22 Mast movement reach cylinder 23 Motor 24 Reduction gear 25-29 Helical gear 30 Brake 31 Rear wheel 32 Fork 33 Panta reach device

Claims (3)

(57) [Claims] 1. A reach truck front wheel is provided at the distal end portion of the Richiregu with the mast is disposed between the machine base pair of right and left extending forward of Richiregu, machine base body and the machine Fixed to the stand body and reach leg in front of the machine stand
A pair of reach leg guides that guide and support movably backward
Move the guide rail and reach leg forward and backward with respect to the rear
Reach mechanism for reach leg movement to change the source
If, with the motor for front wheel drive in which the drive shaft is fixed to Richiregu behind the mast so as to be parallel to the front wheel rotating shaft and a reduction gear for transmitting the driving force of the motor to the front wheels A reach-type forklift characterized by that: 2. A pair of mast guide rails fixed to the reach leg and guideably supporting the mast in the front-rear direction along the reach leg, and a mast movement for moving the mast in the front-rear direction with respect to the reach leg. The reach-type forklift according to claim 1 , further comprising a reach cylinder. 3. The reach-type forklift according to claim 1 , further comprising a punter reach device for supporting the fork movably in the front-rear direction with respect to the mast, wherein the mast is fixed to the reach leg.