CN102536964A

CN102536964A - Protection device for hydraulic reversing system

Info

Publication number: CN102536964A
Application number: CN2011104596246A
Authority: CN
Inventors: 陈展
Original assignee: Shanghai Electric Hydraulics and Pneumatics Co Ltd
Current assignee: Shanghai Electric Hydraulics and Pneumatics Co Ltd
Priority date: 2011-12-31
Filing date: 2011-12-31
Publication date: 2012-07-04
Anticipated expiration: 2031-12-31
Also published as: CN102536964B

Abstract

The invention discloses a protection device for a hydraulic reversing system, which comprises a variable-displacement ram pump (1.1) and a quantitive plunger motor (1.2) which form a return circuit, and further comprises a ball valve (4.5), a shuttle valve (4.6), a main overflow valve (4.1) and a pilot overflow valve (4.2), wherein a valve core is arranged in the valve cavity of the main overflow valve (4.1); a first upper hydraulic fluid port, a second upper hydraulic fluid port, an oil unloading port, and a spring for propping the valve core downwards, which are communicated into the valve cavity, are arranged at the upper part of the valve cavity; and a first lower hydraulic fluid port and a second lower hydraulic fluid port, which are blocked by the blocking valve core propped by the spring, are arranged at the lower part of the valve cavity. The protection device has the advantages that the structure is simple; the failure rate is low; and the system can be protected automatically.

Description

Hydraulic pressure reversing mechanism protective gear

Technical field

The invention belongs to the hydraulics field, relate in particular to a kind of hydraulic pressure reversing mechanism protective gear.

Background technique

At present existing steering device of vehicles adopts motor to drive usually, but for heavy vehicle, like vehicles such as Hoisting Machinery or tanks, because the weight of vehicle own is very big, with motor driving enough driving forces can't be provided, and adopts hydraulic driving usually for this reason.But, the existing baroque problem of hydraulic pressure reversing mechanism protective gear ubiquity, and also exist in case there is fault to occur causing hydraulic circuit to stop up and then damage the problem of whole system.

Summary of the invention

For this reason, technical problem to be solved by this invention provides a kind of simple in structure, hydraulic pressure reversing mechanism protective gear that can play self-protection when breaking down, to overcome the deficiency that existing technology exists.

For solving the problems of the technologies described above, the present invention adopts following technological scheme:

A kind of hydraulic pressure reversing mechanism protective gear comprises the Variable plunger pump 1.1 and quantitative piston motor 1.2 that form the loop, it is characterized in that: also include ball valve 4.5, shuttle valve 4.6, main relief valve 4.1, precursor overflow valve 4.2 and guide's direction-control apparatus;

Said main relief valve 4.1 has spool in valve pocket; The spring that said valve pocket top has last first hydraulic fluid port that is communicated in the valve spring chamber, last second hydraulic fluid port, unloading port and said spool is resetted downwards, said valve pocket bottom have following first hydraulic fluid port and following second hydraulic fluid port that under spring action, is separated by the spool shutoff;

The A filler opening of following first hydraulic fluid port of said main relief valve 4.1, the C filler opening of ball valve 4.5, shuttle valve 4.6 all is communicated on first oil circuit in left side of quantitative piston motor 1.2, and the B filler opening of following second hydraulic fluid port of said main relief valve 4.1, the D filler opening of ball valve, shuttle valve 4.6 all is communicated on second oil circuit on right side of quantitative piston motor 1.2;

The P oil outlet of said shuttle valve 4.6 is constant to draw the last first hydraulic fluid port entering valve spring chamber of low pressure oil through main relief valve 4.1, and the M oil outlet of said ball valve 4.5 is constant to draw high pressure oil is connected to main relief valve 4.1 through throttle valve 5.1 last second hydraulic fluid port; And system high pressure oil is connected to precursor overflow valve 4.2 through unloading port, the throttle valve 5.2 of said main relief valve 4.1.

Adopt technique scheme, that hydraulic pressure reversing mechanism protective gear of the present invention has is simple in structure, rate of fault is low, can carry out the advantage of self-protection.

Description of drawings

Be elaborated below in conjunction with accompanying drawing and embodiment the present invention:

Fig. 1 is a system architecture schematic representation of the present invention.

Embodiment

As shown in Figure 1, hydraulic pressure reversing mechanism protective gear of the present invention comprises guide's direction-control apparatus 3, forms the Variable plunger pump 1.1 in loop, quantitative piston motor 1.2 and ball valve 4.5, shuttle valve 4.6, main relief valve 4.1 and precursor overflow valve 4.2.

Wherein, the loop comprises first loop 100 and second loop 200 that is positioned at quantitative piston motor 1.2 right sides that is positioned at quantitative piston motor 1.2 left sides.

Main relief valve 4.1 has spool in valve pocket; Valve pocket top has the spring that is communicated to interior last first hydraulic fluid port of valve pocket, last second hydraulic fluid port, unloading port and said spool is pushed up downwards, and the valve pocket bottom has at spring to be replaced down by following first hydraulic fluid port of spool shutoff, following second hydraulic fluid port, following the 3rd hydraulic fluid port.

Ball valve 4.5 has C filler opening, D filler opening and M oil outlet, through the rolling of steel ball in it, can realize the connection of C filler opening and M oil outlet or the connection of D filler opening and M oil outlet respectively.

Shuttle valve 4.6 has A filler opening, B filler opening and P oil outlet, and its two ends are through perception oil pressure size and compare and decide A filler opening and the connection of P filler opening or B filler opening and P oil outlet to be communicated with.

The A filler opening of following first hydraulic fluid port of main relief valve 4.1, the C filler opening of ball valve 4.5, shuttle valve 4.6 all is communicated on first oil circuit in left side of quantitative piston motor 1.2, and following second hydraulic fluid port of main relief valve 4.1, the 3rd hydraulic fluid port, the D filler opening of ball valve, the B filler opening of shuttle valve 4.6 all are communicated on second oil circuit on quantitative piston motor 1.2 right sides down.

The P oil outlet of shuttle valve 4.6 is communicated to last first hydraulic fluid port of main relief valve 4.1, and the M oil outlet of ball valve 4.5 is connected to last second hydraulic fluid port of main relief valve 4.1 through throttle valve 5.1; The unloading port of main relief valve 4.1 is connected to precursor overflow valve 4.2, electromagnetism bypass valve 4.3 and mechanically actuated bypass valve 4.4 through throttle valve 5.2.

The one-way valve 2.1 of parallelly connected pair of opposing also on Variable plunger pump 1.1; Wherein the filler opening of two one-way valves 2.1 oil pump 6.1 that interconnects and be connected to the fuel tank place connects first oil circuit and second oil circuit respectively with 8, two one-way valve 2.1 oil outlets of low-pressure safety valve.The outlet port of oil pump 6.1 is provided with filter parallel with one another 6.11 and one-way valve 6.12.

More than be exactly hydraulic pressure reversing mechanism protective gear of the present invention, its working method is following:

Variable plunger pump 1.1 rotates under driven by motor; True dip direction and angle of inclination through swash plate in the controlled variable plunger pump 1.1; And then can realize that hydraulic oil (high pressure oil) is that first oil circuit from the left side gets into quantitative piston motor 1.2 or gets into quantitative piston motor 1.2 from second oil circuit on right side; Thereby control the sense of rotation of the output shaft of quantitative piston motor 1.2, and then reach the purpose that turns to.

Shuttle valve 4.6 structures assurance connection is drawn low pressure oil and is got into main relief valve 4.1 spring chambers (last first hydraulic fluid port); Ball valve 4.2 structures assurance connection is drawn high pressure oil and is got into second hydraulic fluid port on the main relief valve 4.1, and is connected to precursor overflow valve 4.2, electromagnet cut off valve 4.3 and hand stop valve 4.4 through unloading port and throttle valve 5.2; Main relief valve 4.1 because under the acting in conjunction of the hydraulic oil of spring, valve pocket internal upper part and bottom hydraulic oil, its inner spool blocks down first hydraulic fluid port, second hydraulic fluid port, the 3rd hydraulic fluid port down down, main relief valve is equilibrium of forces up and down.

First oil circuit of supposing the left side is a high pressure oil; When system occurs when unusual; During the instantaneous rising of the left side first oil circuit pressure, the oil pressure momentary value that at this moment gets into first hydraulic fluid port of main relief valve 4.1 bottoms will be much larger than last first hydraulic fluid port that gets into main relief valve 4.1 tops and the hydraulic fluid pressure and the spring force of last second hydraulic fluid port, so promotes spool and move upward; Thereby make win hydraulic fluid port and second hydraulic fluid port connection (hydraulic oil on top is then laid down through unloading port); The oil circuit and second oil circuit directly are communicated with even win, and play the pressure release effect, Variable plunger pump and quantitative piston motor in the protective system.Otherwise if second oil circuit on right side is a high-pressure oil passage, the stressing conditions of main relief valve spool both sides is the same.

Through above-mentioned detailed description, can find out hydraulic pressure reversing mechanism protective gear of the present invention have simple in structure, rate of fault is low, can carry out the advantage of self-protection.

But; Those of ordinary skill in the art will be appreciated that; Above embodiment is used for explaining the present invention; And be not to be used as qualification of the present invention, as long as in connotation scope of the present invention, all will drop in claims scope of the present invention the above embodiment's variation, modification.

Claims

1. hydraulic pressure reversing mechanism protective gear; Comprise the Variable plunger pump (1.1) and the quantitative piston motor (1.2) that form the loop, it is characterized in that: also include ball valve (4.5), shuttle valve (4.6), main relief valve (4.1), precursor overflow valve (4.2) and guide's direction-control apparatus;

Said main relief valve (4.1) has spool in valve pocket; The spring that said valve pocket top has last first hydraulic fluid port that is communicated in the valve spring chamber, last second hydraulic fluid port, unloading port and said spool is resetted downwards, said valve pocket bottom have following first hydraulic fluid port and following second hydraulic fluid port that under spring action, is separated by the spool shutoff;

The A filler opening of following first hydraulic fluid port of said main relief valve (4.1), the C filler opening of ball valve (4.5), shuttle valve (4.6) all is communicated on first oil circuit in left side of quantitative piston motor (1.2), and the B filler opening of following second hydraulic fluid port of said main relief valve (4.1), the D filler opening of ball valve, shuttle valve (4.6) all is communicated on second oil circuit on right side of quantitative piston motor (1.2);

The P oil outlet of said shuttle valve (4.6) is constant to draw the last first hydraulic fluid port entering valve spring chamber of low pressure oil through main relief valve (4.1), and the M oil outlet of said ball valve (4.5) is constant to draw high pressure oil is connected to main relief valve (4.1) through throttle valve (5.1) last second hydraulic fluid port; And system high pressure oil is connected to precursor overflow valve (4.2) through unloading port, the throttle valve (5.2) of said main relief valve (4.1).

2. hydraulic pressure reversing mechanism protective gear according to claim 1 is characterized in that: said throttle valve (5.2) is also connected to electromagnetism bypass valve (4.3) and mechanically actuated bypass valve (4.4).