JPS5843498Y2 - Pressure accumulator using torsion bar - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a pressure accumulating device for a vehicle, and more particularly to a pressure accumulating device using a torsion bar as an elastic body for accumulating pressure in a pressure accumulator.

BACKGROUND OF THE INVENTION Hydraulic pressure is used in vehicles, particularly large vehicles such as cargo handling vehicles and transport vehicles, to facilitate the operation of steering devices and braking devices.

In addition, in such vehicles, a pressure accumulator is installed as a hydraulic energy compensation device when the hydraulic pump that generates hydraulic pressure stops, and for the purpose of buffering pump pulsation and protecting the operating mechanism. There is.

The energy source of the pressure accumulator is the reaction force caused by the elastic deformation of a pressure accumulating elastic body such as a spring or gas-filled rubber.

For example, in the gas-filled pressure accumulator 5 shown in FIG.
A rubber bag 1 with N2 gas sealed inside is housed in a casing 2, and by supplying pressurized fluid from a boat 4 to the gap 3 between the rubber bag 1 and the casing 2, the rubber bag 1 is contracted and its elasticity is reduced. The reaction force caused by deformation is stored as energy.

However, it is difficult to completely seal the %N2 gas, and gas filling devices for filling N2 gas from the boat 4' are not installed everywhere, and serviceability in the market is poor.

Furthermore, there are also problems with the durability of the rubber membrane 1 and its resistance to pressure-accumulating fluids.

In the coil spring type pressure accumulator 15 shown in FIG. It is designed to compress and store the reaction force caused by the elastic deformation as energy.

However, the coil springs 11 and 12 are much larger than the piston 8, and the size of the coil springs 11 and 12 determines the overall size of the pressure accumulator 15.

In addition, in order to increase the energy density, the coil spring 11
, 12 are double-layered inside and outside, which makes the structure complicated.Furthermore, the coil springs 11 and 12 need to be pre-compressed during assembly, making assembly difficult. Against this background, the present invention was developed with the aim of making the pressure accumulator as compact as possible by eliminating the dedicated pressure accumulating elastic body from the pressure accumulator. In order to achieve this objective, it has been decided to utilize torsion bars, which have been conventionally provided in vehicles to rotate, move, etc. predetermined members.

In other words, the feature of the present invention is that the base ends of the pair of arms are fixed to a torsion bar whose both ends are rotatably supported by a pair of support arms protruding from the main frame of the vehicle, and one arm is free. Here, one end is connected to the tilt cabin and the free end of the other arm is connected to the piston rod of the pressure accumulator.

Embodiments of the present invention will be described in detail below with reference to the drawings.

FIGS. 3 to 6 show an example in which the present invention is applied to a forklift truck equipped with a tilt cabin.

In FIG. 3, a pair of left and right main frames 21L and 21R that constitute the body of a forklift truck have pins 22
A tilt cabin 23 is pivotally connected by L and 22R.

The tilt cabin 23 is rotated (opened and closed) when servicing equipment placed below it, and the torsion bar mechanism described later is activated by touching the front and rear pillars 233t and 23b. After the locking stay (not shown) is rotated using the reaction force until it is fixed, it is held in the open state by fixing the safety stay.

Further, a locking device 24 is provided between the rear pillar 23a and the left main frame 21L, which is activated when the tilt cabin 23 is in a closed state.

The tilt cabin 23 has a left main frame 21L.
A torsion bar mechanism 50 installed in is connected.

As shown in an enlarged view in FIG. 4, this torsion bar mechanism 50 includes a pair of support arms 25.26 fixed to the inner surface of the vertical wall 21L' of the main frame 21L, and supports both of them via bearings 27.28. A torsion bar 30 is rotatably supported by arms 25 and 26, and the base end of the arm 35 is welded near one end of the torsion bar 30 in a direction perpendicular to the axis of the torsion bar 30. The base end of the arm 36 is fitted into the spline shaft portion 37 at the other end, with the base end of the arm 36 facing in the same direction as the arm 35 .

The free end of the right arm 35 in FIG. 4 of both arms is connected to a connector ( (not shown).

On the other hand, a piston rod 66 of a pressure accumulator 60 shown in FIG. 5 is connected to the free end of the left arm 36 in FIG.

That is, the pressure accumulator 60 includes a cylinder 63 that is tightened and fixed to a flange member 62 in which a boat 61 is bored, and a seal 6.
4 and a piston 65 slidably fitted to the cylinder 63 via the clevis 45 and the pin 44. One end of the rod 66 is connected to the piston 65 by a pin 68.
It is connected to the free end of the arm 36 by.

As shown in FIG. 6, the pressure accumulator 60 includes an engine 70.
The hydraulic oil pumped up from the tank 80 by the pump 75 rotated by the pressure side division and flow switching valve 85
The supply is accumulated through the pressure control and flow switching valve 85 as necessary, and then supplied to the operating mechanism (braking mechanism in this case) 9.
0.

Next, the operation of this embodiment will be explained.

If the tilt cabin 23 is closed before the engine 70 is started, and there is no accumulating fluid in the piston chamber 63a of the accumulator 60, when the tilt cabin 23 is closed, the right arm 35 will be moved due to the weight of the cabin. The torsion bar 30 rotates in the D direction through the
6 to push down the piston 65.

When the piston 65 comes into contact with the flange member 62, the downward movement of the piston 65 is blocked and the left arm 36 stops rotating, but the right arm 35 continues to rotate downward as the tilt cabin 23 continues to move downward. As the torsion bar 30 moves, twisting is imparted to the torsion bar 30.

Therefore, the piston 65 receives the torsional reaction force of the torsion bar 30 and comes into contact with the flange member 62.

The torsion angle and torsion torque range (θ
1 to θ3. T1'7T3).

In this state, the engine 70 is started and the hydraulic oil pumped up from the tank 80 by the pump 75 is pumped in the direction of the arrow B in the center of FIG. 6 and is supplied from the boat 61 of the pressure accumulator 60 into the piston chamber 63a. 23
is fixed by the lock device 24, so the right arm 35 is also fixed, so as the pressure inside the piston chamber 63a increases, the piston 65 is pushed up until it abuts against the ceiling 67 of the cylinder 63. The torsion bar 30 is further twisted, and its torsion angle and torsion torque change to the ranges shown by θ2 to θ4 and T2 to T4 in FIG. 7, respectively.

The above-mentioned torsional torque T4 is selected to be just the right size for the operator to open the tilt cabin 23, so that after removing the locking device 24, the pillar 232) 23b
The tilt cabin 23 can be easily released by applying a slight force.

As the tilt cabin 23 is released, the torsion angle and torsion torque of the torsion bar 30 gradually decrease.
Since the force required to rotate the tilt cabin 23 gradually decreases as it approaches the upper part of the straight line connecting 2R, there is no need to increase the force applied by hand.

When the tilt cabin 23 is in the open state, the torsion angle and torsion torque of the torsion bar 30 have the magnitudes shown by θ2 and T2 in FIG. 7, respectively.

Additionally, in order to ensure that the piston 65 is always in the raised position when the tilt cabin 23 is opened as described above, and thereby perform the opening operation as smoothly as possible, a pressure detection means is provided in the pressure accumulator 60, etc. It is desirable to be able to open the tilt cabin 23 after confirming that the set maximum pressure has been reached.

After releasing the tilt cabin 23, fix the safety stay,
A predetermined service is performed on the equipment below the tilt cabin 23.

When the service is completed, the tilt cabin 23 is closed by performing the reverse procedure to that described above.

In the closed state, the torsion angle and torsion torque of the torsion bar 30 are again shown at θ4 and T4 in FIG. 7, respectively.

Next, the operation of the pressure accumulator will be described.

During operation of the engine 70, hydraulic oil is pumped not only in the direction of arrow C in FIG.
This is continued until the pressure within the cylinder 63 reaches the rising end and the pressure within the cylinder 63 reaches the set maximum value.

In this way, when sufficient energy has been accumulated in the pressure accumulator 60, the engine 70 is stopped and the pump 7 is turned off.
5 is stopped for some reason and the pressure supply to the pressure control and flow switching valve 85 is no longer available, the pressure accumulator 60 becomes the hydraulic pressure supply source, and the hydraulic fluid accumulated inside it is used for pressure control and flow switching. through the valve 85 as shown by arrow C in Fig. 6.
direction into the control mechanism 90.

As a result, the control mechanism 90 is operated with sufficient response speed, and the vehicle can be reliably and quickly decelerated or stopped.

When hydraulic oil is supplied to the brake mechanism 90, the pressure within the cylinder 63 of the pressure accumulator 60 decreases slightly, but the hydraulic oil is immediately reinforced and the pressure within the cylinder 63 is returned to the maximum set value.

In this embodiment, a torsion bar mechanism 50, which has been conventionally disposed within the main frame 21L in order to rotate the tilt cabin 23 as an elastic body for accumulating pressure in the pressure accumulator 60, is used.
Because of this, unlike the conventional case where an elastic body for accumulating pressure is built into the accumulator, in the accumulator 60, the cylinder 63 and piston 65, which are not essential to the accumulator, are eliminated, making it extremely compact and compact. It has a simple structure.

In other words, unlike the conventional example shown in FIG. 2, the size of the coil springs 11 and 12, which are elastic bodies for accumulating pressure, no longer determines the size of the entire pressure accumulator 15. .

Further, the braking mechanism 90 as an operating mechanism is normally operated when the vehicle is running (strictly speaking, when the engine 70 is operating), but the tilt body 23 is normally in a closed state at this time.

Therefore, since the torsional torque of the torsion bar 30 is large and the pressure of the pressure accumulator 60 is sufficiently high, it does not vary much throughout the entire stroke of the piston 65 (corresponding to the difference between the torsional torques T3 and T4 in FIG. 7). Therefore, the pressure accumulator 60 can supply the brake mechanism 90 with hydraulic oil at a stable pressure at all times.

Note that when the tilt cabin 23 is opened with the engine 70 not operating, the torsion angle and torsion torque of the torsion bar 30 are changed from θ1 and T1 to θ in FIG.
3 and T3, which is due to θ
Since it is only slightly smaller than the case of changing from θ2 and T2 to θ4 and T4, opening of the tilt cabin 23 will not be difficult.

Furthermore, the torsion bar mechanism 50, which also serves as the pressure accumulating elastic body of the pressure accumulator 60, can be installed using the elongated space within the main frames 21L and 21R, so that it does not take up space for other equipment. There is no.

Further, the shape, size, etc. of the pressure accumulator 60 can be arbitrarily selected, and the mechanism operated by the pressure accumulator 60 may be, for example, a steering mechanism in addition to the braking mechanism 90. It goes without saying that other than the examples, changes and improvements may be made as appropriate without departing from the spirit of the invention.

As detailed above, according to the present invention, in a pressure accumulating device for a vehicle, a torsion bar, which has been conventionally provided for rotating or moving a predetermined member, is used as an elastic body for accumulating pressure. It becomes possible to eliminate the pressure accumulating elastic body from the pressure accumulator, and the structure of the pressure accumulator becomes simple and compact, resulting in the effect that the pressure accumulator becomes inexpensive.

[Brief Description of the Drawings] Figures 1 and 2 are front sectional views showing a conventional pressure accumulator, respectively, and Figure 3 is a perspective view (one side view) showing the front of a forklift as a vehicle to which the present invention is well applied. Fig. 4 is an enlarged view of the torsion bar mechanism shown in Fig. 3, Fig. 5 is a longitudinal sectional view of the pressure accumulator shown in Fig. 4, and Fig. 6 is a cross-sectional view of the forklift shown in Fig. 3. The operation system explanatory diagram, FIG. 7, is a graph showing the relationship between the torsion angle of the torsion bar and the torsion reaction force in the embodiment shown in FIGS. 3 to 6. 22L, 22R: Main frame, 23: Tilt cabin, 24: Locking device, 25, 26: Support arm, 30 Ni-jo-jo bar, 35, 36: Arm, 50 Ni-jo-jo bar mechanism, 60: Pressure accumulator, 63 Niji cylinder , 65: Piston, 66: Piston rod, 70: Engine, 75
: Pump, 80: Tank, 85: Pressure control and flow switching valve, 90: Braking mechanism.

Claims (1)

[Scope of utility model registration request] The base ends of the pair of arms are fixed to a torsion bar whose both ends are rotatably supported by a pair of support arms protruding from the main frame, and the free end of one arm is attached to the tilt cabin, and the free end of the other arm is attached to the torsion bar. A pressure accumulating device characterized in that a torsion bar is used as a pressure accumulating elastic body of the pressure accumulator by connecting the torsion bars to the piston rods of the pressure accumulator.