A outrigger sequence extension system and a fire truck

Abstract

The utility model relates to the technical field of fire engine support leg hydraulic telescopic, specifically relates to a support leg sequence telescopic system and height -raising fire engine, including car body, horizontal support leg, vertical support leg, horizontal oil cylinder, vertical oil cylinder and horizontal reversing valve, the clearance that changes along with vertical support leg telescopic is equipped with between horizontal support leg and car body, the clearance is installed in the travel valve, and its i mouth is connected horizontal reversing valve through shuttle valve, and o mouth connects oil tank, when vertical support leg supports and stretches out, clearance reduces and makes travel valve to connect, and horizontal oil cylinder pressure is relieved through overflow valve, and horizontal support leg is forced to lock, when vertical support leg retracts, clearance increases and makes travel valve to disconnect, and horizontal support leg can freely contract, the application realizes sequence control through pure mechanical structure, avoids the damage of support leg caused by manual misoperation, and travel valve is fixed on car body and simplifies pipeline layout.

Description

Technical Field

[0001] This utility model relates to the field of hydraulic telescopic outrigger technology for fire trucks, specifically to a sequential telescopic outrigger system and an aerial fire truck. Background Technology

[0002] To maintain stability when getting on the vehicle, modern aerial fire trucks are equipped with four symmetrical support devices on their chassis structure. Each support device includes horizontal outriggers and vertical outriggers.

[0003] When the support system is in operation, the horizontal outriggers must be extended first, followed by the vertical outriggers, to support the entire vehicle. For example... Figure 1 As shown, during retraction, the vertical outriggers must be retracted first, followed by the horizontal outriggers. The extension and retraction of the outrigger cylinders are driven by the directional valves of the hydraulic system. When the directional valve is switched to the extended position, the outrigger cylinders extend; when the directional valve is switched to the retracted position, the outrigger cylinders retract. The directional valves can be electrically controlled or manually operated.

[0004] Under normal circumstances, the system operates electronically. The electronic control program logic determines whether the vertical outriggers are retracted, thus restricting the movement of the horizontal outriggers. However, in the event of a power outage or electronic control failure, manual operation of the directional valve is required as an emergency measure to retract the outriggers. Because manual operation of the directional valve lacks the electronic control program's limitations, it is prone to misoperation. If the vertical outriggers are still supporting the horizontal outriggers and have not retracted, retracting the horizontal outriggers could cause deformation or damage to the vertical outriggers. Utility Model Content

[0005] The technical objective of this invention is to design a sequential extension and retraction system for outriggers and an elevated fire truck. Existing hydraulic systems cannot achieve sequential extension and retraction of outriggers during manual operation; errors in judgment or operation can lead to damage to the outriggers.

[0006] To achieve the above-mentioned technical objectives, this utility model provides the following technical solution:

[0007] In a first aspect, a leg extension and retraction system includes a vehicle body, horizontal and vertical outriggers connected to each other, a horizontal cylinder and a vertical cylinder for driving the extension and retraction of the horizontal and vertical outriggers respectively, and a horizontal directional valve for controlling the extension and retraction of the horizontal cylinders.

[0008] When the horizontal outrigger is extended, there is a gap between it and the vehicle body that varies with the extension and retraction of the vertical outrigger.

[0009] The outrigger sequential telescopic system also includes:

[0010] A shuttle valve is used to select a pressurized oil passage when there is operating pressure at the horizontal directional valve, and transmit that pressure to the stroke valve.

[0011] A stroke valve includes an inlet (i) and an outlet (o), wherein the inlet (i) is connected to the oil outlet of a shuttle valve, and the outlet (o) is connected to an oil tank; the stroke valve is installed within the gap and is used to disconnect and connect the inlet (i) and outlet (o) respectively under a first operating condition and a second operating condition; wherein...

[0012] In the second operating condition, the gap decreases, causing the stroke valve core to be compressed to the on position, and the output pressure of the horizontal cylinder is less than the friction between the vertical outrigger and the ground; in the first operating condition, the gap increases, causing the stroke valve core to reset to the off position, and the horizontal outrigger can retract under the drive of the horizontal cylinder.

[0013] Furthermore, the shuttle valve includes a first oil port, a second oil port, and an oil outlet; the first oil port and the second oil port are respectively connected to the rod-side oil port and the rodless-side oil port of the horizontal cylinder.

[0014] Furthermore, the first working condition is the vertical outrigger retracted state, at which time the stroke valve is in the open position;

[0015] The second operating condition is when the vertical outrigger extends to support the vehicle, and the stroke valve is in the ON position.

[0016] Furthermore, when the stroke valve is in the ON position, the I port and O port of the stroke valve are connected;

[0017] When the stroke valve is in the off position, the i-port and o-port of the stroke valve are cut off.

[0018] Furthermore, the stroke valve is mounted on the vehicle body and indirectly contacts the horizontal outrigger.

[0019] Furthermore, it also includes an overflow valve, the inlet of which is connected to the O port of the stroke valve, and the outlet of which is connected to the oil tank.

[0020] Furthermore, it also includes a vertical directional valve for controlling the extension and retraction of the vertical hydraulic cylinder.

[0021] Secondly, an elevated fire truck includes a vehicle body and multiple symmetrically arranged outrigger structures mounted on the vehicle body. The outrigger structures include the outrigger sequential telescopic system described in the first aspect, used to prevent support failure or structural damage caused by incorrect outrigger operation sequence in power failure or manual mode.

[0022] Compared with the prior art, the beneficial effects achieved by this utility model are as follows:

[0023] This application achieves outrigger sequence control by installing a stroke valve between the vehicle body and the horizontal outriggers and utilizing the gap changes caused by the vertical outriggers under different working conditions to control the opening and closing of the stroke valve: when the vertical outriggers are not retracted, the stroke valve is in the on state due to the reduced gap, thereby restricting the movement of the horizontal outriggers and avoiding damage to the outriggers due to misoperation; at the same time, the stroke valve is arranged on the vehicle body and does not need to move with the horizontal outriggers, so the hydraulic system pipeline layout is more convenient and there are no moving pipelines. Attached Figure Description

[0024] To more clearly illustrate the specific embodiments of this utility model or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0025] The above and other aspects of the present invention will now be described by way of example only, with reference to the accompanying drawings, in which:

[0026] Figure 1 This is a schematic diagram of the hydraulic circuit of an existing outrigger sequential telescopic system;

[0027] Figure 2 This is a schematic diagram of the hydraulic circuit of a sequential extension and retraction system for outriggers provided by this utility model;

[0028] Figure 3 This is a schematic diagram of the retracted state of the vertical outrigger of the outrigger sequential telescopic system provided by this utility model;

[0029] Figure 4 This is a schematic diagram of the vertical support state of a leg sequential telescopic system provided by this utility model;

[0030] Figure 5 This is a schematic diagram of the installation position of the stroke valve in a leg sequential telescopic system provided by this utility model.

[0031] In the diagram: 1. Body; 2. Horizontal cylinder; 3. Vertical cylinder; 4. Horizontal directional valve; 5. Vertical directional valve; 6. Horizontal outrigger; 7. Vertical outrigger; 8. Stroke valve; 9. Shuttle valve; 10. Relief valve. Detailed Implementation

[0032] To better understand the above technical solutions, the following will provide a detailed explanation of the technical solutions in conjunction with the accompanying drawings and specific implementation methods.

[0033] Example 1:

[0034] like Figure 2As shown, this embodiment provides a leg sequential telescopic system.

[0035] A sequential extension and retraction system for outriggers includes a vehicle body 1, a horizontal cylinder 2, a vertical cylinder 3, a horizontal reversing valve 4, a vertical reversing valve 5, a horizontal outrigger 6, a vertical outrigger 7, a stroke valve 8, a shuttle valve 9, and an overflow valve 10.

[0036] Shuttle valve 9 is used to select a pressurized oil passage when there is operating pressure at the horizontal directional valve 4, and transmit the pressure to the stroke valve 8; specifically, when the vertical outrigger 7 extends, the shuttle valve 9 transmits the pressure to the stroke valve 8 and sends the hydraulic oil back to the oil tank through the pipeline.

[0037] In the second working condition, that is, when the vertical support leg 7 is extended and supporting, the gap is reduced and the valve core of the stroke valve 8 is compressed to the on position. At this time, the horizontal support leg needs to retract after the vertical support leg is retracted. In the first working condition, that is, when the vertical support leg 7 is retracted, the gap is increased and the valve core of the stroke valve 8 is reset to the off position. At this time, the horizontal support leg can retract freely.

[0038] The stroke valve 8 is a mechanical hydraulic stroke switch (with roller), installed in the gap between the horizontal outrigger 6 box and the vehicle body 1; wherein: port 0 is directly connected to the oil tank; port 1 is connected to the oil outlet of the shuttle valve 9;

[0039] like Figure 4 and Figure 5 As shown, when the vertical support leg 7 extends to support, the gap decreases, the valve core of the stroke valve 8 is compressed to the on position, and port i and port o are connected.

[0040] like Figure 3 and Figure 5 As shown, when the vertical support leg 7 retracts, the gap increases, the valve core of the stroke valve 8 resets to the open position, and the i port and the o port are cut off.

[0041] The shuttle valve 9 includes: a first oil port and a second oil port that are respectively connected to the rod chamber oil port and the rodless chamber oil port of the horizontal oil cylinder 2, and an oil outlet that is connected to the i port of the stroke valve 8;

[0042] The inlet of the relief valve 10 is connected to the O port of the stroke valve 8, and the outlet is connected to the oil tank. A pressure threshold is set.

[0043] Working principle: When the vertical support leg 7 is in the retracted state, the stroke valve 8 is in the open position (i.e., port i and port 0 are not connected), the oil circuit is not connected, and the valve stem of the horizontal support leg 6 is pushed, so the horizontal support leg 6 can extend and retract freely without restriction.

[0044] When the vertical outrigger 7 is extended and in the supporting position, the pulley of the stroke valve 8 is compressed and in the ON position (i.e., ports I and O are connected). The oil flows back to the oil tank through the stroke valve 8, then through the relief valve 10 and connected to port T. Because the vertical outrigger 7 is in the supported position, the horizontal outrigger 6 needs to overcome the ground friction to move. However, the set pressure of the relief valve 10 is too low to allow the horizontal cylinder 2 to overcome the ground friction; therefore, pushing the valve stem of the horizontal outrigger 6 will prevent the horizontal outrigger 6 from moving. In other words, when the vertical outrigger 7 is not retracted, the horizontal outrigger 6 cannot be moved, thus achieving sequential extension and retraction and protecting the outriggers.

[0045] The purpose of setting the overflow valve 10 is to prevent the stroke valve 8 from jamming or malfunctioning: the vertical outrigger 7 is in the retracted state, but the horizontal outrigger 6 still cannot move due to the jamming or malfunction of the stroke valve 8. Therefore, the overflow valve 10 is set so that when the stroke valve 8 is jammed or malfunctioning, the overflow valve 10 can still build up a certain pressure. Because the vertical outrigger 7 is retracted at this time, there is no friction on the ground. This pressure can make the horizontal outrigger 6 extend and retract, thus improving the reliability of the vehicle. Example 2:

[0046] A fire truck with a raised platform is provided, including a vehicle body 1 and multiple sets of symmetrical outrigger structures installed at the bottom of the vehicle body 1. Each set of outrigger structures includes a horizontal outrigger 6 and a vertical outrigger 7. The horizontal outrigger 6 is connected to the vehicle body 1 through a sliding mechanism, and one end of the horizontal outrigger 6 is hinged to the vertical outrigger 7. The vertical outrigger 7 is used to contact the ground to provide vertical support force.

[0047] The horizontal outrigger 6 is extended and retracted by a horizontal hydraulic cylinder 2, and the vertical outrigger 7 is extended and retracted by a vertical hydraulic cylinder 3. The two cylinders are controlled by a horizontal reversing valve 4 and a vertical reversing valve 5, respectively. To achieve outrigger sequence control and prevent damage to the equipment caused by the horizontal outrigger 6 being retracted due to the vertical outrigger 7 not retracting, the aerial ladder fire truck is also equipped with an outrigger sequence extension and retraction system as mentioned in Embodiment 1.

[0048] The description herein is provided to enable those skilled in the art to implement or use the present disclosure. Various modifications to the present disclosure will be readily apparent to those skilled in the art, and the general principles defined herein can be applied to other variations without departing from the scope of the disclosure. Therefore, this disclosure is not limited to the examples and designs described herein, but should be given the broadest scope consistent with the principles and novel features disclosed herein.

[0049] Although the present disclosure has been described in detail above with general descriptions and specific embodiments, modifications or improvements can be made to the embodiments of the present disclosure, which will be obvious to those skilled in the art. Therefore, all such modifications or improvements made without departing from the spirit of the present disclosure are within the scope of protection claimed by the present disclosure.

Claims

1. A leg extension and retraction system, comprising a vehicle body (1), horizontal legs (6) and vertical legs (7) connected together, horizontal cylinders (2) and vertical cylinders (3) for driving the extension and retraction of the horizontal legs (6) and vertical legs (7) respectively, and a horizontal directional valve (4) for controlling the extension and retraction of the horizontal cylinders (2); characterized in that, The horizontal outrigger (6) has a gap with the vehicle body (1) that varies with the extension and retraction of the vertical outrigger (7) when it is extended. The outrigger sequential telescopic system also includes: A shuttle valve (9) is used to select a pressurized oil passage when there is operating pressure at the horizontal directional valve (4) and transmit the pressure to the stroke valve (8). The stroke valve (8) includes an i-port and an o-port, wherein the i-port is connected to the oil outlet of the shuttle valve (9), and the o-port is connected to the oil tank; the stroke valve (8) is installed in the gap and is used to disconnect and connect the i-port and the o-port respectively under the first working condition and the second working condition; wherein, In the second working condition, the gap decreases, causing the valve core of the stroke valve (8) to be compressed to the on position, and the output pressure of the horizontal cylinder (2) is less than the friction between the vertical support leg (7) and the ground; in the first working condition, the gap increases, causing the valve core of the stroke valve (8) to be reset to the off position, and the horizontal support leg (6) can retract under the drive of the horizontal cylinder (2).

2. The outrigger sequential telescopic system according to claim 1, characterized in that, The shuttle valve (9) includes a first oil port, a second oil port and an oil outlet; the first oil port and the second oil port are respectively connected to the rod-side oil port and the rodless-side oil port of the horizontal cylinder (2).

3. The outrigger sequential telescopic system according to claim 1, characterized in that, The first working condition is that the vertical support leg (7) is retracted, and the stroke valve (8) is in the open position at this time; The second working condition is when the vertical support leg (7) is extended and supported, and the stroke valve (8) is in the on position.

4. The outrigger sequential telescopic system according to claim 1, characterized in that, When the stroke valve (8) is in the ON position, the i port and the O port of the stroke valve (8) are connected; When the stroke valve (8) is in the off position, the i port and o port of the stroke valve (8) are cut off.

5. The outrigger sequential telescopic system according to claim 1, characterized in that, The stroke valve (8) is mounted on the vehicle body (1) and is in indirect contact with the horizontal outrigger (6).

6. The outrigger sequential telescopic system according to claim 1, characterized in that, It also includes an overflow valve (10), the inlet of which is connected to the port of the stroke valve (8), and the outlet is connected to the oil tank.

7. The outrigger sequential telescopic system according to claim 1, characterized in that, Also includes: Vertical reversing valve (5) controls the extension and retraction of vertical cylinder (3).

8. A fire truck with elevated platform, characterized in that, The system includes a vehicle body (1) and multiple sets of symmetrically arranged outrigger structures mounted on the vehicle body (1). The outrigger structures include an outrigger sequential telescopic system as described in any one of claims 1-7, which is used to prevent support failure or structural damage caused by incorrect outrigger operation sequence in power failure or manual mode.

Images