JPS6357322B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a garbage collection vehicle, and more particularly to a garbage collection vehicle having an improved locking device for tightening and releasing a tailgate with respect to a garbage storage box.

The garbage collection vehicle has a garbage storage box that stores garbage inside, and a tailgate with a built-in loading device is provided at the rear of the garbage storage box so that it can be opened and closed.
The garbage bin and tailgate are unlocked using a locking device. This type of locking device has a construction in which a locking pin on the tailgate side engages a hook on the side of the garbage container, and the hook is moved by a lock cylinder device.

The conventional hydraulic circuit for operating this lock cylinder device connects a pipe branched from the discharge side of the hydraulic pump to the head side of the lock cylinder device, returns the pipe from the rod side to the drain circuit, and connects these pipes to the head side of the lock cylinder device. It had a locking switching valve built into the pipe. The lock device is tightened and released by this hydraulic circuit by switching the lock switching valve and expanding and contracting the piston rod of the lock cylinder device. In this type of lock cylinder device, in order to prevent the locking pin from accidentally disengaging from the hook, the rod always receives hydraulic pressure in the direction of protrusion due to the difference in pressure receiving area. There is.

For this reason, for some reason, the piston rod of the lock cylinder device may protrude and be in the locked position while the tailgate is being raised. The locking of the tailgate to the storage box becomes impossible.

SUMMARY OF THE INVENTION An object of the present invention is to provide a garbage collection vehicle in which a lock cylinder device for locking a garbage storage box and a tailgate can be reliably operated hydraulically.

In order to achieve the above object, the present invention provides a hydraulically driven single-shaft operated lock cylinder device on the vehicle body side of the garbage storage box, connects this lock cylinder device to a hydraulic power source via a switching valve, and In a garbage collection vehicle in which the piston rod of the cylinder device rotates the hook to tighten and release the hook against the engagement pin on the tailgate side, a pressure oil pipe to the cylinder chamber on the piston side of the lock cylinder device is installed. A hook switching valve is connected to the road that guides the piston chamber of the lock cylinder device to the drain side while the tailgate is rising and holds the hook in the release position, and the switching valve switches the hook when the tailgate completes its descent. The present invention is characterized by the provision of a tailgate lowering confirmation switch which advances the piston rod of the lock cylinder device via a switching valve to tighten the hook.

According to the present invention, while the tailgate is in the raised position, the tailgate lowering confirmation switch operates, and the first switching valve 26 switches to the direction of contracting the piston of the locking cylinder device 18, thereby releasing the hook 16. position, and when the tailgate is completely lowered, the tailgate lowering confirmation switch operates, switches the first switching valve 26, advances the piston of the locking cylinder device 18, and locks the hook 1.
6 and the engagement pin 14.

A garbage collection vehicle according to the present invention will be explained below with reference to the drawings.

In FIG. 1, reference numeral 1 indicates a garbage storage box, and the rear opening of this garbage storage box 1 is opened and closed by a tailgate 2. As shown in FIG.
As is well known, the tailgate 2 is composed of both side plates 2a and a sump 2b forming a bottom plate. It is pivoted. A conveyor panel 5 is rotatably mounted on the sump 2b of the tailgate 2 by a pivot 6, and the tip of the conveyor panel 5 is moved along the sump 2b by a drive device (not shown). It rotates and scoops up the garbage placed on the sump 2b into the garbage storage box 1 while moving it along the arrow A.

Above the conveyor panel 5, a ram panel 7 is pivotally attached to the tailgate side plate 2a by a pivot 8. The ram panel 7 swings around a pivot shaft 8 as shown by arrow B, and the swing is performed by a ram cylinder device 9. The ram panel 7 has a portion 7a projecting upward from its pivot 8, and the tip of this portion 7a is attached to a pivot 10 at the tip of a piston rod 9a of the ram cylinder device 9.
It is pivoted by. The upper end of the cylinder 9b of the ram cylinder device 9 is pivotally connected to the bracket 3 by a pivot 11. Therefore, when the ram cylinder device 9 contracts, the ram panel 7 hits the tip of the conveyor panel 5 with its back surface and rotates about the axis 4 from the position shown by the solid line in FIG. 1 to the position shown by the imaginary line. I'm starting to be able to do it.

When discharging garbage, the tailgate 2 is rotated to the position shown by the imaginary line in FIG. 1 as described above, but after loading the garbage, it must be securely held at the position shown by the solid line in FIG. A tailgate locking mechanism 12 is provided for this purpose.

As shown in FIG. 2, this locking mechanism 12 consists of an engaging pin 14 fixed behind the sump 2b of the tailgate and a locking hook 16 pivotally connected to the side of the garbage storage box 1 by a pin 15. It has The hook 16 is held by a locking cylinder device 18, and the tip of the piston rod 19 of the cylinder device 18 is attached to the hook 16 by a pin 19a.
When hydraulic pressure is supplied behind the piston 20 of the cylinder device 18, the hook 16 continues to be engaged with the engagement pin 14 to keep the tailgate 2 in the locked state. On the other hand, when the piston 20 retreats and the piston rod 19 retracts, the hook 16
is disengaged from the engagement pin 14, and the tailgate 2 can be opened.

However, a tailgate lowering confirmation switch LS-1 is installed at the rear lower end of the vehicle body on which the garbage storage box 1 is mounted.
is provided, and when the tailgate 2 finishes descending to the position shown by the solid line in Fig. 1, the circuit is closed by the tailgate sump 2b and becomes the ON state, and when the tailgate 2 starts to rise. OFF
act to become a state. On the other hand, the hook 1
A micro switch is located near 6 to detect whether the tailgate is locked or unlocked.
LS-2 and LS-3 are provided, and these micro switches LS-2 and LS-3 are turned ON when the hook 16 is released and the lock is turned on.
When the engagement pin 14 is engaged and locked, the engagement pin 14 is in an OFF state.

In FIG. 1, reference numeral 21 indicates a discharge plate that moves in the front and back direction within the garbage storage box 1, and this discharge plate 21 is driven by a cylinder device 22. indicates a deflector panel.

Next, the hydraulic circuit and electric circuit of the above-mentioned garbage collection vehicle will be explained.

In FIG. 3 showing the hydraulic circuit, the head side of the discharge cylinder device 22 is connected to SOLa via a pipe 25.
1 and SOLb1, and the rod side is connected to port B of the first switching valve 26 via a conduit 27. Further, the hydraulic motor that drives the conveyor panel 5 is connected via pipes 28 and 29 to ports A and B of a second switching valve 30 that is switched by SOLa2 and SOLb2. Further, the ram cylinder device 9 is connected via pipes 31 and 32 to ports A and B of a third switching valve 33 which is switched by SOLa3 and SOLb3. These first, second and third switching valves 2
Reference numerals 6, 30, and 33 are center bypass type four-port three-position switching valves.

On the other hand, a pipe line 35 is connected to the P port of the first switching valve 26.
A hydraulic pump 36 is connected through the PTO, and the hydraulic pump 36 is driven by power from the engine through the PTO. Further, the port R of the first switching valve 26 is connected to the pipe line 37 so as to bypass the port PR of the second switching valve 30 and the third switching valve 33 in the neutral position.
38 , and port R of the third switching valve 33 is connected to a drain circuit 39 .

Further, a pipe line 35 on the discharge side of the hydraulic pump 36
A pipe line 40 branches off from there, and a relief valve 41 is installed on the way.
It is connected to the P port of the fourth switching valve 42 which is switched by SOLa4 and SOLb4. A pipe line 43 is connected to the A port of this fourth switching valve 42.
The end of this conduit 43 is connected to the conduit 31, and furthermore, a throttle 45 is installed on the conduit 31.

Furthermore, the rod side of the lock cylinder device 18 is connected to the middle of the pipe 25 via a pipe 46, while a port R is blocked on the pipe 27 on the rod side of the discharge cylinder device 22. A fifth switching valve 47 (hook switching valve) with 4 ports and 2 positions is incorporated. Port B of this fifth switching valve 47
is connected to the head side of the lock cylinder device 18 via a line 48.

Next, an electric circuit for operating the above-mentioned hydraulic circuit will be explained with reference to FIG.

In the figure, LS-1 is a tailgate lowering confirmation switch, which is configured as two pairs of interlocking double-throw switches, whose normally closed contact _C9 is connected to the busbar N via SOLa1, while the normally open contact _C10 is connected to SOLb1. It is connected to bus N via. Also, one normally open contact
_C12 is connected to bus N via SOL4.

Further, SW1 indicates a tailgate switch connected to the bus P, and its fixed terminal _C1 is connected to SOLa3 through parallel micro switches LS-2 and LS-3 for detecting the locked or unlocked state of the tailgate. and connected to SOLb1. Furthermore, fixed terminals C ₂ and C ₃ are connected to bus bar N via SOL5.

Further, SW2 indicates a discharge plate operation switch connected to the bus P, and the fixed terminal _C7 is connected to the bus N via SOLb1, while the fixed terminal _C8 is connected to the bus N.
It is connected to bus N via SOLa1.

In the figure, SW3 indicates a main switch, and E indicates a DC power supply.

Next, the operation will be explained with reference to FIGS. 3 and 4.

When the tailgate 2 is in the raised position shown by the imaginary line in Fig. 1, the tailgate lowering confirmation switch LS-1 is in the OFF state and the micro switches LS-2 and LS-3 are in the OFF state in Fig. 4.
It is in ON state. From this state, if you switch tailgate switch SW-1 to the down position, the fixed terminal
Since C ₆ is closed and tailgate 2 is in the raised position, the tailgate lowering confirmation switch LS-1 has already been activated.
The normally open contact _C12 of is closed and energizes SOLb4.
Then, the rod side of the ram cylinder device 9 becomes the throttle 4.
5. It is switched to the drain side through the pipes 43 and 50, and the tailgate 2 is lowered by its own weight. At the same time, terminal _C2 of the tailgate switch SW1 closes, so SOL5 of the fifth switching valve 47
is energized, and tailgate switch SW1 is activated.
Since the terminal _C4 of is closed and the tailgate 2 is in the raised position, the normally open contact _C10 of LS-1 is also already closed, so SOLb1 is energized. Therefore,
Pressurized oil from the hydraulic pump 36 is directed to the rod side of the lock cylinder device 18 through the first switching valve 26 to contract the piston 20 and move the hook 16 to the release position. At this time, the lock cylinder device 1
The pressure oil on the head side of No. 8 is connected to the pipe 48 and the fifth switching valve 47.
and is returned to the drain side via the first switching valve 26. As a result, the hook 16 of the locking device can be returned to the release position before the tailgate 2 is completely lowered. When the tailgate 2 is completely lowered, the tailgate lowering confirmation switch LS-1 returns to the ON state and the normally closed contact _C9 closes. When SOLa1 of the first switching valve 26 is energized and switched, SOL5 of the lock cylinder device 47 is energized, so the pressure oil from the hydraulic pump 36 passes through port B of the first switching valve 26 to the fifth switching valve. Pressure oil is supplied to the conduit 48 via the valve 47, and is further supplied to the head side of the lock cylinder device 18, which advances the piston 20 and rotates the hook 16 around the pivot 15, thereby connecting the hook 16 and the engagement pin. 14.

As is clear from the above description, according to the present invention, the direction of flow of pressure oil to the lock cylinder device that drives the hook is switched while the tailgate is being moved from the raised position to the lowered position, so that the hook can be unlocked as soon as possible. Since the tailgate is returned to the position and then switched to the lock position again, the tailgate is not inadvertently moved to the lock position and becomes unable to be locked, and the tailgate can be reliably locked to the vehicle body.

The relief valve 41 is effective in draining the pressure oil from the pump 36 from the circuit 40 to the circuit 50 when the lock cylinder is relieved at the end of the stroke by completely releasing the hook while the tailgate is lowering.

[Brief explanation of drawings]

Fig. 1 is a longitudinal sectional view showing the area around the tailgate of the garbage collection vehicle according to the present invention, Fig. 2 is an enlarged front view showing the locking device of the tailgate, and Fig. 3 is a longitudinal sectional view showing the vicinity of the tailgate of the garbage collection vehicle according to the present invention. discharge cylinder device,
FIG. 4 is a hydraulic circuit diagram for operating the lock cylinder device and the ram cylinder device, and FIG. 4 is an electric circuit diagram for operating the hydraulic circuit. DESCRIPTION OF SYMBOLS 1... Garbage storage box, 2... Tail gate, 5... Conveyor panel, 7... Ram panel, 9... Ram cylinder device, 12... Tail gate lock mechanism, 16... Hook, 18... Lock cylinder device, 14... Engagement pin.

Claims (1)

[Claims] 1 Hydraulic driven single shaft operated lock cylinder device 1
8 is provided on the vehicle body side of the garbage storage box, and this lock cylinder device is connected to the hydraulic power source 36 via the switching valve 26, and the piston rod of the lock cylinder device 18 rotates the hook 16 to engage the lock cylinder device on the tailgate side. In the garbage collection vehicle in which the hook is tightened and released from the dowel pin, there is a pressure oil pipe on the pressure oil pipe between the head side chamber of the lock cylinder device 18 and the switching valve 26, which locks when the tailgate is lowered. A hook switching valve 47 that guides the head side chamber of the cylinder device to the drain side is connected, and a hook switching valve 47 is connected between the rod side chamber of the lock cylinder device and the switching valve 26.
and is connected by a pressure oil pipe, and the switching valve 26 advances the piston rod of the lock cylinder device 18 via the hook switching valve 47 to tighten the hook when the tailgate completes lowering. Collection car.