阅读说明：本技术 一种压缩式垃圾车及其液压系统 (Compression garbage truck and hydraulic system thereof ) 是由 彭敏 张振龙 于 2021-07-06 设计创作，主要内容包括：本发明提供了一种压缩式垃圾车及其液压系统,该液压系统的刮板油缸和滑板油缸共同通过三位四通液控换向阀(1)与液压泵相连,而且,两者通过单向顺序阀(5和6)使一者的液压腔与另一者的液压腔相连,以此形成关联联动,在上述三位四通液控换向阀的控制方面,借助两个控制阀(2和4)、一个梭阀(10)以及两个压力发讯器(11和23)的合理设置,实现了上料(即翻桶作业)与压填的联合作业。采用本发明提供的液压系统可使执行油缸实现关联联动,有利于提高垃圾车的自动化作业能力,从而降低工人劳动强度,提高作业效率。(The invention provides a compression garbage truck and a hydraulic system thereof, wherein a scraper oil cylinder and a slide plate oil cylinder of the hydraulic system are connected with a hydraulic pump through a three-position four-way hydraulic control reversing valve (1) together, and a hydraulic cavity of one is connected with a hydraulic cavity of the other through one-way sequence valves (5 and 6) so as to form related linkage, and in the aspect of control of the three-position four-way hydraulic control reversing valve, the combined operation of loading (namely barrel turning operation) and pressure filling is realized by virtue of reasonable arrangement of two control valves (2 and 4), a shuttle valve (10) and two pressure transmitters (11 and 23). The hydraulic system provided by the invention can realize the associated linkage of the execution oil cylinders, and is beneficial to improving the automatic operation capacity of the garbage truck, thereby reducing the labor intensity of workers and improving the operation efficiency.)

1. A hydraulic system of a compression garbage truck is characterized in that a hydraulic pump is connected with a scraper cylinder and a sliding plate cylinder through a pressure filling valve by pipelines, and the pressure filling valve is a three-position four-way hydraulic control reversing valve;

a first working oil port of the pressure filling valve is connected with a rodless cavity of the scraper oil cylinder through a first main path and is connected with a rod cavity of the sliding plate oil cylinder through a first one-way sequence valve through a first branch path bypassing the first main path;

a second working oil port of the pressure filling valve is connected with a rod cavity of the scraper oil cylinder through a second main path and is connected with a rodless cavity of the sliding plate oil cylinder through a second one-way sequence valve through a second branch path bypassing the second main path;

the control cavity of the pressure filling valve is connected with the hydraulic pump through a first control valve and a second control valve in sequence through pipelines, the first control valve is a two-position four-way hydraulic control reversing valve, and the second control valve is a normally closed two-position two-way hydraulic control reversing valve;

a control cavity of the first control valve is connected with one end, far away from the rod cavity, of the sliding plate oil cylinder through a shuttle valve and a first pressure signal transmitter in sequence through a pipeline, the first pressure signal transmitter is connected to a first inlet of the shuttle valve, and a second inlet of the shuttle valve is connected with a second working oil port of the pressure filling valve through a pipeline;

the control cavity of the second control valve is connected with the barrel turning oil cylinder through a second pressure signal transmitter through a pipeline, one end of the barrel turning oil cylinder, which is far away from the second pressure signal transmitter, is provided with a position sensor, and a piston rod of the barrel turning oil cylinder is provided with an induction sleeve matched with the position sensor.

2. The hydraulic system of claim 1, wherein the hydraulic pump is connected to the lift cylinder and the lock cylinder via a discharge valve via a pipeline and to the blade cylinder via a blade valve via a pipeline, the discharge valve and the blade valve being three-position, four-way, hydraulically controlled directional valves;

a first working oil port of the discharge valve is connected with a rod cavity of the lifting oil cylinder through a third main path and is connected with a rodless cavity of the locking oil cylinder through a third one-way sequence valve through a third branch path bypassing the third main path;

a second working oil port of the discharge valve is connected with a rodless cavity of the lifting oil cylinder through a fourth main path and is connected with a rod cavity of the locking oil cylinder through a fourth branch path bypassing the fourth main path;

the control cavity of the unloading valve is sequentially connected with the hydraulic pump through a third control valve and a fourth control valve through pipelines, the control cavity of the push shovel valve is sequentially connected with the hydraulic pump through a fifth control valve and the fourth control valve through pipelines, the third control valve and the fifth control valve are both two-position four-way hydraulic control reversing valves, and the fourth control valve is a two-position four-way electromagnetic reversing valve;

the control cavity of the third control valve is connected with one end, far away from the rodless cavity, of the shovel oil cylinder through a shuttle valve and a third pressure signal transmitter through a pipeline, and the control cavity of the fifth control valve is connected with one end, far away from the rodless cavity, of the lifting oil cylinder through a fourth pressure signal transmitter through a pipeline.

3. The hydraulic system of claim 2, wherein the rodless cavity of the blade cylinder is connected with a hydraulic oil tank through a sixth control valve by a pipeline, the sixth control valve is a normally closed two-position two-way hydraulic control reversing valve, and a control cavity of the sixth control valve is connected with the rodless cavity of the sliding plate cylinder by a pipeline.

4. The hydraulic system according to any one of claims 1 to 3, wherein the hydraulic pump is connected to the barrel-tilting cylinder through a pipeline via a three-position four-way electromagnetic directional valve.

5. A compression garbage truck characterized by comprising the hydraulic system according to any one of claims 1 to 4.

Technical Field

The invention relates to the technical field of environmental sanitation equipment, in particular to a compression type garbage truck and a hydraulic system thereof.

Background

The compression type garbage truck comprises a sealed garbage compartment, a hydraulic system, an operating system and the like, wherein an execution oil cylinder of the hydraulic system comprises a bucket turning oil cylinder, a scraper oil cylinder, a sliding plate oil cylinder, a push shovel oil cylinder, a lifting oil cylinder and a locking oil cylinder, and the functions of the execution oil cylinders are introduced as follows:

the garbage can turning cylinder controls the garbage turning mechanism to act, and garbage is transferred from the garbage can to a filling hopper of the filling device (namely, loading operation). The scraper oil cylinder controls the scraper of the filler to open outwards and close inwards, and scrapes the garbage in the filling hopper. The sliding plate oil cylinder controls the sliding plate of the filler to move, and drives the scraping plate to scrape garbage into the garbage compartment from the filling hopper. The push shovel oil cylinder controls the push shovel to move, the push shovel pushes out the garbage in the garbage compartment during unloading operation, and the push shovel cooperates with the scraper plate to extrude the garbage during press filling operation. The lifting oil cylinder controls the action of the lifting mechanism, and lifts the filler to open the rear end of the garbage compartment during the unloading operation. The locking oil cylinder controls the locking mechanism to act, and the filler is locked on a station during press filling operation.

The existing hydraulic system has the disadvantages that each execution oil cylinder needs to be operated independently, linkage is lacked, and the working efficiency is influenced, so how to improve the hydraulic system to improve the working efficiency becomes a technical problem to be solved by technical personnel in the field.

Disclosure of Invention

In view of the above, the invention provides a compression-type garbage truck and a hydraulic system thereof, and the hydraulic system can realize the associated linkage of the execution oil cylinders, and is beneficial to improving the automatic operation capacity of the garbage truck, thereby reducing the labor intensity of workers and improving the operation efficiency.

In order to achieve the purpose, the invention provides the following technical scheme:

a hydraulic system of a compression garbage truck is characterized in that a hydraulic pump is connected with a scraper cylinder and a sliding plate cylinder through a pressure filling valve by pipelines, and the pressure filling valve is a three-position four-way hydraulic control reversing valve;

a first working oil port of the pressure filling valve is connected with a rodless cavity of the scraper oil cylinder through a first main path and is connected with a rod cavity of the sliding plate oil cylinder through a first one-way sequence valve through a first branch path bypassing the first main path;

a second working oil port of the pressure filling valve is connected with a rod cavity of the scraper oil cylinder through a second main path and is connected with a rodless cavity of the sliding plate oil cylinder through a second one-way sequence valve through a second branch path bypassing the second main path;

the control cavity of the pressure filling valve is connected with the hydraulic pump through a first control valve and a second control valve in sequence through pipelines, the first control valve is a two-position four-way hydraulic control reversing valve, and the second control valve is a normally closed two-position two-way hydraulic control reversing valve;

a control cavity of the first control valve is connected with one end, far away from the rod cavity, of the sliding plate oil cylinder through a shuttle valve and a first pressure signal transmitter in sequence through a pipeline, the first pressure signal transmitter is connected to a first inlet of the shuttle valve, and a second inlet of the shuttle valve is connected with a second working oil port of the pressure filling valve through a pipeline;

the control cavity of the second control valve is connected with the barrel turning oil cylinder through a second pressure signal transmitter through a pipeline, one end of the barrel turning oil cylinder, which is far away from the second pressure signal transmitter, is provided with a position sensor, and a piston rod of the barrel turning oil cylinder is provided with an induction sleeve matched with the position sensor.

Optionally, in the hydraulic system, the hydraulic pump is connected to the lift cylinder and the lock cylinder through a discharge valve via a pipeline, and is connected to the shovel cylinder through a shovel pushing valve via a pipeline, and the discharge valve and the shovel pushing valve are both three-position four-way hydraulic control directional valves;

a first working oil port of the discharge valve is connected with a rod cavity of the lifting oil cylinder through a third main path and is connected with a rodless cavity of the locking oil cylinder through a third one-way sequence valve through a third branch path bypassing the third main path;

a second working oil port of the discharge valve is connected with a rodless cavity of the lifting oil cylinder through a fourth main path and is connected with a rod cavity of the locking oil cylinder through a fourth branch path bypassing the fourth main path;

the control cavity of the unloading valve is sequentially connected with the hydraulic pump through a third control valve and a fourth control valve through pipelines, the control cavity of the push shovel valve is sequentially connected with the hydraulic pump through a fifth control valve and the fourth control valve through pipelines, the third control valve and the fifth control valve are both two-position four-way hydraulic control reversing valves, and the fourth control valve is a two-position four-way electromagnetic reversing valve;

the control cavity of the third control valve is connected with one end, far away from the rodless cavity, of the shovel oil cylinder through a shuttle valve and a third pressure signal transmitter through a pipeline, and the control cavity of the fifth control valve is connected with one end, far away from the rodless cavity, of the lifting oil cylinder through a fourth pressure signal transmitter through a pipeline.

Optionally, in the hydraulic system, a rodless cavity of the blade cylinder is connected to a hydraulic oil tank through a sixth control valve via a pipeline, the sixth control valve is a normally closed two-position two-way hydraulic control directional valve, and a control cavity of the sixth control valve is connected to the rodless cavity of the slide plate cylinder via a pipeline.

Optionally, in the hydraulic system, the hydraulic pump is connected to the barrel-turning cylinder through a pipeline via a three-position four-way electromagnetic directional valve.

A compression-type refuse collection vehicle comprising a hydraulic system as disclosed in any one of the preceding claims.

According to the technical scheme, in the hydraulic system for the compression type garbage truck, the scraper oil cylinder and the sliding plate oil cylinder are connected with the hydraulic pump through the three-position four-way hydraulic control reversing valve together, the hydraulic chamber of one oil cylinder is connected with the hydraulic chamber of the other oil cylinder through the one-way sequence valve, so that the linkage is formed, and in the aspect of control of the three-position four-way hydraulic control reversing valve, the combined operation of loading (namely, barrel turning operation) and pressure filling is realized by means of reasonable arrangement of two control valves (namely, a two-position four-way hydraulic control reversing valve and a normally closed two-position two-way hydraulic control reversing valve), a shuttle valve and two pressure transmitters (namely, a first pressure transmitter and a second pressure transmitter). Therefore, the hydraulic system provided by the invention is beneficial to improving the automatic operation capacity of the garbage truck, thereby reducing the labor intensity of workers and improving the operation efficiency.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the provided drawings without creative efforts.

Fig. 1 is a circuit diagram of a hydraulic system of a compression-type garbage truck according to an embodiment of the present invention.

Labeled as:

1. 28, 30-three-position four-way hydraulic control reversing valve;

3-three-position four-way electromagnetic directional valve;

4. 27, 31-two-position four-way hydraulic control reversing valve;

29-two-position four-way electromagnetic directional valve;

2. 26-two-position two-way hydraulic control reversing valve;

5. 6, 33-sequence valve;

24. 25, 32-one-way valve;

10-shuttle valve;

7-scraper cylinder; 8, a sliding plate oil cylinder; 9-a feeding oil cylinder;

34-locking oil cylinder; 35-a filler cylinder; 38-a blade cylinder;

11. 23, 36, 37-pressure transmitter;

21-a position sensor; 22-induction sleeve.

In the drawings, to make the reference numeral conspicuous, the numeral is indicated in a circled form, and for example, "r" in the drawings is a reference "1".

Detailed Description

For the purpose of facilitating understanding, the present invention will be further described with reference to the accompanying drawings.

Referring to fig. 1, the hydraulic system for the compression-type garbage truck according to the embodiment of the present invention includes a three-position four-way hydraulic control directional control valve 1 (i.e., a pressure filling valve), and the hydraulic pump is connected to a scraper cylinder 7 and a slide plate cylinder 8 through the three-position four-way hydraulic control directional control valve 1 by a pipeline.

The port A (i.e. the first working oil port) of the three-position four-way hydraulic control reversing valve 1 is connected with the rodless cavity of the scraper oil cylinder 7 through a first main path and is connected with the rod cavity of the sliding plate oil cylinder 8 through a first one-way sequence valve (consisting of a sequence valve 5 and a one-way valve 24) through a first branch path bypassing the first main path.

The port B (i.e. the second working oil port) of the three-position four-way hydraulic control reversing valve 1 is connected with the rod cavity of the scraper oil cylinder 7 through a second main path and is connected with the rodless cavity of the sliding plate oil cylinder 8 through a second branch path bypassing the second main path and a second one-way sequence valve (consisting of a sequence valve 6 and a one-way valve 25).

A control cavity of the three-position four-way hydraulic control reversing valve 1 is sequentially connected with a hydraulic pump through a two-position four-way hydraulic control reversing valve 4 (namely a first control valve) and a normally closed two-position two-way hydraulic control reversing valve 2 (namely a second control valve) through pipelines, wherein the control cavity of the two-position four-way hydraulic control reversing valve 4 is sequentially connected with one end, far away from the rod cavity, of the sliding plate cylinder 8 through a shuttle valve 10 and a pressure transmitter 11 (namely a first pressure transmitter) through pipelines, the pressure transmitter 11 is connected to a first inlet of the shuttle valve 10, and a second inlet of the shuttle valve 10 is connected with a port B of the three-position four-way hydraulic control reversing valve 1 through a pipeline;

the control cavity of the two-position two-way hydraulic control reversing valve 2 is connected with the feeding oil cylinder 9 (namely, a barrel turning oil cylinder) through a pipeline by a pressure signal generator 23 (namely, a second pressure signal generator), one end of the feeding oil cylinder 9, which is far away from the pressure signal generator 23, is provided with a position sensor 21, and a piston rod of the feeding oil cylinder 9 is provided with an induction sleeve 22 matched with the position sensor 21.

In this embodiment, the hydraulic pump is connected to the feeding cylinder 9 through the three-position four-way electromagnetic directional valve 3 via a pipeline, and the working principle of the feeding operation and the press-filling operation is described below:

as shown in fig. 1, firstly, the solenoid valve DT2 of the three-position four-way electromagnetic directional valve 3 is powered on, pressure oil enters the rodless cavity of the feeding oil cylinder 9 to push the barrel turning mechanism to perform feeding operation, after the position sensor 21 senses that the piston rod of the feeding oil cylinder 9 extends out of position through the sensing sleeve 22, in order to ensure that garbage is dumped completely, a control signal is sent to the control system after 2 seconds of delay, then the control system controls the solenoid valve DT2 of the three-position four-way electromagnetic directional valve 3 to be powered off and the solenoid valve DT1 to be powered on, the pressure oil enters the rod cavity of the feeding oil cylinder 9 to push the barrel turning mechanism to return to complete feeding operation.

After a piston rod of the feeding oil cylinder 9 retracts to the right, pressure oil in a rod cavity enters a control cavity of the two-position two-way hydraulic control reversing valve 2 through the pressure communicator 23 to push the two-position two-way hydraulic control reversing valve 2 to be switched to a right working position, system pressure oil enters the control cavity of the three-position four-way hydraulic control reversing valve 1 through the two-position two-way hydraulic control reversing valve 2 and the two-position four-way hydraulic control reversing valve 4 to push the three-position four-way hydraulic control reversing valve 1 to be switched to a left working position, and system pressure oil enters a rodless cavity of the scraper oil cylinder 7 through the three-position four-way hydraulic control reversing valve 1 to push a scraper to be opened outwards (namely the scraper is opened).

After the scraper is opened in place, pressure oil in the rodless cavity of the scraper oil cylinder 7 enters the rod cavity of the sliding plate oil cylinder 8 through the sequence valve 5 when the pressure is suppressed to be greater than the set pressure of the sequence valve 5, the sliding plate is pushed to move outwards (namely the sliding plate slides downwards), and hydraulic oil in the rodless cavity of the sliding plate oil cylinder 8 returns to the oil tank through the one-way valve 25.

After the sliding plate slides downwards to the right, pressure oil in a rod cavity of a sliding plate oil cylinder 8 enters a control cavity of a two-position four-way hydraulic control reversing valve 4 through a pressure communicator 11 and a shuttle valve 10, the two-position four-way hydraulic control reversing valve 4 is pushed to be switched to a right working position, system pressure oil enters the control cavity of a three-position four-way hydraulic control reversing valve 1 through the two-position four-way hydraulic control reversing valve 4, the three-position four-way hydraulic control reversing valve 1 is pushed to be switched to the right working position, at the moment, the pressure communicator 11 is closed, the system pressure oil enters the control cavity of the two-position four-way hydraulic control reversing valve 4 through the shuttle valve 10, the three-position four-way hydraulic control reversing valve 4 is kept at the right working position, the system pressure oil enters a scraper oil cylinder 7 through the three-position four-way hydraulic control reversing valve 1 to have a rod cavity, and scrapes scrapers are pushed to be inwardly folded (namely scraper scraping).

After the scrapers are scraped in place, pressure oil in a rod cavity of the scraper oil cylinder 7 enters a rodless cavity of the sliding plate oil cylinder 8 through the sequence valve 6 when the pressure is suppressed to be greater than the set pressure of the sequence valve 6, the sliding plate is pushed to move inwards (namely the sliding plate slides upwards), hydraulic oil in the rod cavity of the sliding plate oil cylinder 8 returns to the oil tank through the one-way valve 24, and the pressure filling operation is completed after the sliding plate slides in place.

It should be noted that the scrapers are opened and closed outwards, and the sliding plate is moved inwards and outwards, and the "inner" and the "outer" are relative to the garbage compartment, that is, the "inner" refers to the position close to the garbage compartment, and the "outer" refers to the position far away from the garbage compartment.

According to the working principle, the hydraulic system provided by the invention can realize combined operation of feeding and pressing filling, so that the automatic operation capacity of the garbage truck is improved, the labor intensity of workers is reduced, and the operation efficiency is improved.

Referring to fig. 1, the hydraulic system according to the embodiment of the present invention further includes a three-position four-way hydraulic control directional valve 28 (i.e., a discharge valve) and a three-position four-way hydraulic control directional valve 30 (i.e., a push shovel valve), and the hydraulic pump is connected to a filler cylinder 35 (i.e., a lift cylinder) and a lock cylinder 34 through the three-position four-way hydraulic control directional valve 28 via a pipeline, and is connected to a push shovel cylinder 38 through the three-position four-way hydraulic control directional valve 30 via a pipeline.

The port a (i.e., the first working oil port) of the three-position four-way hydraulic control directional control valve 28 is connected to the rod chamber of the filler cylinder 35 through a third main passage, and is connected to the rodless chamber of the lock cylinder 34 through a third one-way sequence valve (composed of a sequence valve 33 and a one-way valve 32) by a third branch passage bypassing the third main passage.

The port B (i.e., the second working fluid port) of the three-position four-way hydraulic control directional valve 28 is connected to the rodless chamber of the filler cylinder 35 through a fourth main passage, and is connected to the rod chamber of the lock cylinder 34 through a fourth branch passage bypassing the fourth main passage.

The control chamber of the three-position four-way hydraulic control directional control valve 28 is connected to the hydraulic pump through a two-position four-way hydraulic control directional control valve 27 (i.e., a third control valve) and a two-position four-way electromagnetic directional control valve 29 (i.e., a fourth control valve) in sequence by a pipeline, and the control chamber of the three-position four-way hydraulic control directional control valve 30 is connected to the hydraulic pump through a two-position four-way hydraulic control directional control valve 31 (i.e., a fifth control valve) and a two-position four-way electromagnetic directional control valve 29 in sequence by a pipeline.

The control chamber of the two-position four-way hydraulic control directional valve 27 is connected with one end of the dozer cylinder 38 far away from the rodless chamber through a shuttle valve 10 and a pressure transmitter 37 (i.e., a third pressure transmitter) by a pipeline, and the control chamber of the two-position four-way hydraulic control directional valve 31 is connected with one end of the filler cylinder 35 far away from the rodless chamber through a pressure transmitter 36 (i.e., a fourth pressure transmitter) by a pipeline.

The working principle of the unloading operation is described as follows:

firstly, the solenoid valve DT3 of the two-position four-way solenoid directional valve 29 is energized, pressure oil enters the control cavity of the three-position four-way pilot operated directional valve 28 from the port B of the two-position four-way solenoid directional valve 29 through the two-position four-way pilot operated directional valve 27 to push the three-position four-way pilot operated directional valve 28 to switch to the right working position, and simultaneously enters the control cavity of the three-position four-way pilot operated directional valve 30 through the two-position four-way pilot operated directional valve 31 to push the three-position four-way pilot operated directional valve 30 to switch to the right working position.

The system pressure oil enters a rod cavity of the locking oil cylinder 34 and a rodless cavity of the filler oil cylinder 35 through the three-position four-way hydraulic control reversing valve 28, and the hydraulic pressure required for overcoming the self weight of the filler is larger than that required for unlocking the locking oil cylinder 34, so that the filler oil cylinder 35 does not act at the moment, the piston rod of the locking oil cylinder 34 retracts, the hydraulic oil in the rodless cavity of the locking oil cylinder 34 returns to the oil tank through the one-way valve 32, and the locking mechanism is opened.

After the locking mechanism is opened in place, the locking oil cylinder 34 is pressurized by pressure oil in the rod cavity, the pressure rises and pushes the filler oil cylinder 35 to act, and the filler is lifted by the lifting mechanism. It should be noted that, before the discharging operation starts, the garbage compartment is filled with garbage, the push shovel cylinder 38 is in the retraction state, at this time, the pressure oil entering the rod cavity of the push shovel cylinder 38 through the three-position four-way hydraulic control directional valve 30 is in the pressure-holding state, and the push shovel cylinder 38 does not operate.

After the filler is lifted to the right position, pressure oil in a rodless cavity of a filler oil cylinder 35 enters a control cavity of a two-position four-way hydraulic control reversing valve 31 through a hydraulic communicator 36, the position four-way hydraulic control reversing valve 31 is pushed to be switched to a right working position, then system pressure oil enters a control cavity of the three-position four-way hydraulic control reversing valve 30 through the two-position four-way electromagnetic reversing valve 29 and the four-way hydraulic control reversing valve 31, the three-position four-way hydraulic control reversing valve 30 is pushed to be switched to a left working position, system pressure oil enters a rodless cavity of a push shovel oil cylinder 38 through the three-position four-way hydraulic control reversing valve 30, and the push shovel oil cylinder 38 extends out to start unloading operation.

After the push shovel oil cylinder 38 is completely extended, pressure oil in a rodless cavity of the push shovel oil cylinder 38 enters a control cavity of the two-position four-way hydraulic control reversing valve 27 through the hydraulic communicator 37, the two-position four-way hydraulic control reversing valve 27 is pushed to be switched to the right working position, system pressure oil enters a control cavity of the three-position four-way hydraulic control reversing valve 28 through the two-position four-way hydraulic control reversing valve 27, the three-position four-way hydraulic control reversing valve 28 is pushed to be switched to the left working position, and the system pressure oil enters a rod cavity of the filler oil cylinder 35 through the three-position four-way hydraulic control reversing valve 28, so that the filler is lowered.

After the filler is put in place, the pressure oil in the rod cavity of the filler oil cylinder 35 starts to be suppressed, when the pressure rises to be greater than the set value of the sequence valve 33, the pressure oil enters the rodless cavity of the locking oil cylinder 34 through the sequence valve 33, the piston rod of the locking oil cylinder 34 extends out to enable the locking mechanism to lock the filler, and the whole unloading operation process is completed.

According to the working principle, the lifting and lowering of the filling device and the unloading operation of the push shovel oil cylinder realize the associated linkage through the pressure signal transmitter and the hydraulic control reversing valve, so that the whole unloading operation process can be completely automatic, and the unloading operation efficiency is improved. In addition, the locking mechanism and the filler are controlled to be interlocked through the self weight of the filler and the sequence valve, and compared with the traditional mode adopting a position sensor, the locking mechanism effectively avoids the problem that the position sensor fails due to the severe working environment, so that the stability of the system is damaged.

In this embodiment, the rodless cavity of the blade cylinder 38 is connected to the hydraulic oil tank via a frequently closed two-position two-way hydraulic control directional control valve 26 (i.e., a sixth control valve) via a pipeline, and the control cavity of the two-position two-way hydraulic control directional control valve 26 is connected to the rodless cavity of the slide plate cylinder 8 via a pipeline. In the process of press filling operation, a piston rod of the sliding plate oil cylinder 8 extends to enable the sliding plate to slide upwards, and the push shovel oil cylinder 38 is in an extending state, so when the garbage is filled into the garbage compartment by the scraping plate, the scraping plate and the push shovel compress the garbage together due to the blocking effect of the push shovel, when the garbage compression amount reaches a certain degree, the sliding resistance of the sliding plate is increased, the pressure of the pressure oil in a rodless cavity of the sliding plate oil cylinder 8 is increased, when the pressure is increased to a set value (for example, 12MPa) of the two-position two-way hydraulic control reversing valve 26, the two-position two-way hydraulic control reversing valve 26 is switched to a right working position, the rodless cavity of the push shovel oil cylinder 38 is communicated with an oil tank through the two-position two-way hydraulic control reversing valve 26, and the push shovel oil cylinder 38 retracts to enable the push shovel to retreat, and the smooth filling of the garbage into the garbage compartment by the scraping plate is ensured.

The invention also provides a compression-type garbage truck which comprises the hydraulic system disclosed by the embodiment. Since the hydraulic system disclosed in the above embodiment has the above technical effects, the compression-type garbage truck having the hydraulic system also has the above technical effects, and the details are not repeated herein.

The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to the embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.