SU1573113A2 - Bulldozer - Google Patents

Abstract

The invention relates to road construction machines and reduces power consumption, simplifies management and improves the performance of a hydroficated dozer. The bulldozer hydraulic drive contains hydraulic cylinders (GC) mounted in pushing bars x 1 - sensors 2. Control chamber 19 of hydraulic distributor (GH) 13 is connected with working cavities of HZ 2 and with rod cavities HZ 8 and 9 of expander 5 and 6 through adjustable throttle 20. GR 13 is made on-off. Rod cavities HZ 8 and 9 are communicated by means of a valve 22 with a drain. With an increase in digging resistance in the piston cavities of HZ 2, the pressure of the working fluid (GF) increases. The pressure in the chamber also increases correspondingly. In the chamber 19, the spool of the ГР 13 rises together with the piston cavities HZ 8 and 9 together with the hydraulic accumulator 14. The pistons HZ 8 and 9 under the pressure of the HJ in HZ 2 overcome the back pressure of the hydroaccumulator 14 and rise. Expanders 5 and 6 are deepened by a certain amount. This reduces the thickness of the cut soil chips and, accordingly, the resistance to digging. When the digging resistance decreases, the expander 5 and 6 are lowered under the action of the RJ pressure from the hydroaccumulator 14. From it, the RJ enters the piston cavities of HZ 8 and 9 through the built-in non-return valve 18. 2 Il.

Description

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The invention relates to construction-road machines, namely to hydraulic drives of earth-moving machines such as bulldozers, is an improvement to the bulldozer about auth. St. No. 1170063.

The aim of the invention is to reduce power consumption, simplify management and increase the productivity of a hydroficated bulldozer.

FIG. 1 shows a front view bulldozer; in fig. 2 - the same, side view and hydraulic circuit of the bulldozer.

The bulldozer contains pushing bars 1 with built-in hydraulic cylinders-sensors 2, which are pivotally attached to the base machine 3. In the front part of the pushing wheels 1, a blade 4 is installed. 8 and 9 of the expanders 5 and 6, the hydraulic cylinders 8 and 9 being fixed to the brackets 10. The piston cavities of the hydraulic cylinders 8 and 9 are communicated by hydraulic lines 11 and 12 through an additional hydraulic control valve 13 with hydraulic accumulator coupling 14, having a make-up system, containing valve 15 connected to the drain and hydraulic valve 16 connected to the pressure main 17. The valve 13 is two-way with a spring-loaded slide valve and with an integrated check valve 18. The control valve 19 of the valve 13 is connected via an adjustable valve the throttle 20 with the piston stations of the hydraulic cylinders 2, which are hydro-21 in communication with the rod strips of the hydraulic cylinders 9, and through the valve 22 - with the drain.

The bulldozer works as follows.

In the working position (Fig. 1 and 2), the bulldozer interacts with the developed soil during the translational movement of the base machine. However, the total digging resistance does not exceed the limit value at which intense skidding begins. Therefore, the valve of the hydraulic distributor 13 is spring-pressed downward, and the expanders 5 and 6 are pressed down to the initial position (Fig. 1 and 2) by the hydraulic cylinders 8 and 9 under the action of the pressure of the hydroaccumulator 14 charged to a predetermined pressure value.

In the event of an increase in the total digging resistance, for example, due to an increase in the strength of the soil, or an increase in the volume of the drawing prism, the pressure of the working fluid in the piston cavities of the hydraulic cylinders 2 and in the control valve 19 communicated with them 13 increases. up jointly piston cavities of hydraulic cylinders

8 and 9 along hydraulic lines 11 and 12 with a hydraulic accumulator 14. Pistons of hydraulic cylinders 8 and 9 overcome the back pressure of hydraulic accumulator 14 and rise up under the action of the aforementioned working fluid pressure in the piston cavities of hydraulic cylinders 2. Expanders 5 and 6 are plunged into some the value that reduces the thickness of the chips they cut and, accordingly, the resistance of the cop

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In the case of a decrease in the total digging resistance, for example, due to a decrease in the strength of the soil, the pressure of the working fluid in the circuit formed by the piston cavities of the hydraulic cylinders 2, the rod cavities of the hydraulic cylinders 9 and the control chamber 19 falls. Therefore, the dilators 5 and 6 descend under the action of the pressure of the working fluid flowing into the piston cavities of the hydraulic cylinders 8 and 9 from the hydraulic accumulator 14 along the hydraulic line 11 and 12 through the hydraulic distributor 13.

In the event that there is a significant decrease in total resistance, for example, due to the deepening of the entire

5 of the blade 4 for conveying accumulated soil, the pressure in the said circuit is significantly reduced and the valve of the hydraulic distributor 13 is spring-loaded down to its original position. Expanders 5 and 6 descend under the pressure of the working fluid from the hydraulic accumulator 14, which enters the piston cavities of the hydraulic cylinders 8 and 9 through the hydraulic lines 11 and 12 and through the built-in non-return valve 18. This prevents loss of soil from the drawing prism during transportation.

5 The limit value of the total digging resistance corresponding to the allowable level of propulsion slipping is set on the basis of specific operating conditions due to a change in the magnitude of the charging pressure of the hydroaccumulator 14 using valve 15 and hydraulic valve 16. The valve 22 serves to fill the hydraulic circuit with working fluid, and the choke 20 serves as a filter preventing accidental

5 turns on the hydraulic distributor 13 at high-frequency changes in the pressure of the working fluid, for example, due to the influence of the cleavage of the soil.

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Claims (1)

Invention Formula Bulldozer on auth. St. No. 1170063, characterized in that, in order to reduce energy consumption, simplify management and increase the productivity of a hydraulic bulldozer, its hydraulic actuator is equipped with hydraulic cylinders mounted in pushing bars, an additional hydraulic control valve that is controlled by an adjustable throttle valve with an operating cavity gauge hydraulic cylinders and with rod cavities of the hydraulic cylinders of the broadeners, and a hydraulic accumulator with a system for feeding it, while the additional hydraulic on-off valve is formed, - nym and in one of its positions torr pressure reservoir connected to the piston cavities of hydraulic cylinders expanders by the built-in an additional check valve distributor and the other - is directly and the rod end of the hydraulic cylinders expanders communicated with drain via valve Fig 1 If.