JPS5954802A - Work equipment drive circuit device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a drive circuit device for making a working machine such as a construction machine sound.

In the conventional system, as shown in FIG. 1, one pump α passes each pulp b, c, d, 'f, to each actuator #,
It was supplied to f and y and drove each work machine. J In the case of such a one-pump system, the entire discharge flow rate of one pump α is unnecessary during operation (during pumping), and if there is a small flow,
In some cases, the extra amount was wasted.

In addition, even for work or machines that require the entire amount of one pump, all
1 is used when the work machine speed is at its maximum, and there are other times when the work machine speed is slowly accelerated to the maximum speed, or when it is slowly decelerated to t. Furthermore, there is a lot of continuous fine-tuning of the production equipment, and even in cases like this, the surplus must be discarded.

In addition, when adding a high-pressure, large-capacity control valve (h), the main valve (1) should be removed and placed in a remote location, in order to reduce the operating cost.

□ In order to control it, it is necessary to add a pilot Kurzo i like the 21st NI and use a type of pyrolyte operation. In that case, it has conventionally been necessary to newly provide a pump as a pilot hydraulic power source.

The present invention was developed in view of the above circumstances, and its purpose is to use one of the two pumps as a pilot and to combine the flow rate of the two pumps to be used to supply the cylinder of the work machine. The purpose of the present invention is to capture and provide a driving circuit position of a working machine that enables the reduction of the number of pumps and the number of piping. explain.

1 and 2 in the drawing are the first. 3 is a control valve for half rate, 4 is a tilt control valve 7-15n control valve, 6 is an unload valve, 17 is a main valve, and 55 is a shuttle valve.

The control valve 3 and the unload valve 6 constitute a proportional control valve 7V with force compensation and compensation.

The control valve 5 has a valve body 91, a valve body 91%, rJ), and a spool hole 921.
″.

The valve body 91 also has chambers 23.30.75, 77.53°22.24.2 communicating with the spool hole 92.
8 is a provision. A spool 19 is fitted into the spool hole 92, and a spring seat 94.95 is attached to the end of the spool 19.
・Both spring seats 94 are provided in contact with the shoulders, respectively.
．． A spring 96 is provided between 95 and 95. The chambers 22, 24 communicate with the chamber 28 through a passage 97, and the passage 97 is provided with a check valve 27.

Said meeting 7. - The valve body is equipped with a valve body 8, and the valve body 9.8 has a sprue hole q9'', +oo.

101 is provided.

The valve body 98 is provided with a chamber 49.51 communicating with the spool hole 99, and the valve body 98 is provided with a chamber 32.35 communicating with the spool hole 100. The communicating chamber 5 (1°73 is provided.

A spool 18 is fitted into the spool hole 99, and the spool 18 is held neutrally by springs 48 and 4da at both ends, and the spool hole
Both ends of 01 are formed into oil chambers 41 and 47.

A spool 33 is fitted into the spool hole 100, and the spool 3311-1. It is held in neutral by a spring 38. The spool 33 has drill holes 37.42 formed therein.

A spool 71 is inserted into the spool hole +01, and this spool 7.1 is held neutrally by a spring 38'.
is formed.

The valve body 98 is provided with a shuttle valve 40,45.

Bo=)40z of the shuttle valve 40 is a passage □39 to chamber +02
7fr: Through υ, shuttle valve 40
) 40b communicates with the chamber 80 via a passage 90 and with the chamber 41 via the boat 40Cf'i spring 9σ.

Bot 4.5G of shuttle valve 45 communicates with chamber 103 via passage 92 and other bows) 45A communicates with chamber 43 via passage 44 and further with other bows), 45? communicates with chamber 47 via passage 46. Room 65 to Room 4
A check valve 66 is provided in the passageway 104 extending from 9 to 9.

The shuttle valve 55 includes a valve body 7.
A spool hole 110 is provided in the spool hole 110.
A plug 57 is attached at the end. Spool hole +1
0 has a spool (2), light, spool 1
A piston 56 is fitted into the end of 2. Spool 1
2 is biased toward the glove side by a spring 58. The valve body 7 is provided with a chamber 9, 59, 60 communicating with the spool hole □12.

The discharge side of the first bong 1 is connected to the chamber 65 of the main valve 17 via a pipe 64, and the discharge side of the first pump is connected to an unload valve via βh4, F3., 6'3. It is connected to boat 6α of No. 6.

The chamber 51 of the main valve 17 does not communicate with the tank 111 through the pipe 7.0. Main valve l'7 is connected to cylinder B'''C, )'+ connect I't>/')・P1・j 47%, ILz7 l
,.

3 is connected to the control node (lup 5) via piping 31.74.
It is connected to chamber 3Q, 75. The piping 20 is connected to the passage 112 (7) of the 21st .zeta. Control valve 5's chamber failure is 嘗心管2! ↑Professional unloading machine! The chamber 23 is connected to the bow 1-6 b, and the chamber 23 is connected to the piping +
5ff, which operates the intermediary 113. Con,
The draw/I/pulp 17 chamber 77 is connected to the tank 111 via a pipe 78.

","'1゛°fuv'Z A/ ,,,7"5"
i4.5 Pique, Pi °' Ji pipe 54 via air"'
Gate 55.

Continuing Isu Goyarben 55 Umuro 60, < (ro,
Connect the pipe line 6 to the board 6d of the IH7 unit 6.

This pilot conduit 62 is provided with a restrictor 11. Said plumbing! 5, the pilot pipe 115 is branched, and this pilot pipe +15.4A/V is connected to the pilot pipe 7)6g of the load valve 6.

Shuttle valve 55 is connected to shuttle valve 10 via pilot passage 1.3. Fourth, let's take a look at the operation. .

, during the engine rotation, the run roll/<ru yj,
', 3.1'', II 4', , 5 is tri
As shown in Fig. 3, when in the medium condition, the flow rate control of 1-3 is in the closed state. ° 'Top pressure ゛ 〃 〃 〃 〃 〃 ・ ・ バ バ バ バ バ バ バ バ バ バ バ バ バ
From the shuttle valve 10 to the control valve 3' through the drain passage 14 through the bird 8 notched in the
++(i::+m is connected, so unload valve 6
4 is in the state shown in FIG. 4, and the first valve 1 is in an alleload state at low pressure. On the other hand, the flow rate of the second pump 2 is piped through the control valve 4.5. -doyZ'k 7"67'), No.. Illustrated condition.

, and the second pump 2 is also in an unloaded state at low pressure.

When the spool 19i of the control valve 5 is pulled (7,1, the flow from the chamber 22.2"4 of the pump 2 is closed) At the same time, the check valve 27 is opened and the flow passes from the chamber 28 to the spout.
From the chamber 32 of the main control valve 17 through the conduit 31 from 0 to the chamber 3 through the notch 34 of the differential pressure valve spool.
When the flow is introduced into the bottom and side of the ripper cylinder 16 through the flow pipe 36, the pressure is high! The pressure on the vertical pressure side before passing through the notch 34 of P) is the pressure on the spool 3. The chamber of the spool 33 from the drilled hole 37 in i. ．． 8' passage 1
39・,'/'(Fk valve 49 way failure 7pa ↑7°1
One end of 7-3boo↑18 is led to chamber 41 where 0 pressure chamber 7 is located. On the other hand, the pressure on the lower side □ after passing through the sick leave 2.4 of the spool 33 is passed through the hole 42 and the hole 42 in the spool 33, and is led to the chamber 43 of the cispool 33.
4, 464, 7
', "K" m. Koshimaka spool 1'8' is
The pressure chambers are chambers 41 and 4.7.0 and chamber 47. The main valve 17 moves until it balances with the inner spring 4'g. and 35 from closed to open. .

Further, the chamber 50 which is connected to the ripper cylinder 160 lot side is also the chamber 51 which is the tank boat of the main valve 17.
Change the relationship between the two to a negative state or an open state.

On the other hand, the pull signal 7'' of the control valve 5 changes the state between the chamber 24 and the chamber 53 from the closed state to the open state by the notched groove 52 cut out in the spool 19, and the pump pressure is transferred to the pilot pipe 54.
Since the piston 56 provided in the spool 12 of the Layator valve 55 is held down by the plug 57, the spool 12 moves to the left against the spring 58, and the notch 8 that opened the chambers 60 and 9 opens. is closed, chambers 59 and 60 are opened at the constriction 61 of the spool 12, and the pilot 'R
The passage 62 leads to the spring chamber 11111 of the unload valve 6 through the restrictor 11. As a result, the pressure of the second pump 2 forces the unload valve 6, which was in the unloading state of the fourth tooth, into the on-loading state, as shown in the fifth slope, and the first pump 1 also becomes under high pressure, and the piping is connected to the branch point 63. The check valve 66 is pushed open from the chamber 65 which is the pump boat of the main valve 17 through the chamber 49, and the spool 18 is opened.
The flow passes through the constriction 67 of the ripper cylinder 16, merges with the flow rate of the second pump 2 in the chamber 35, and flows toward the cylinder bottom side.
The return flow I, 1 from the cylinder rod side extends from the pipe 68 to the chamber 50, passes through the constriction 69 of the spool IS in the open state, and flows from the tank boat chamber 51 to fj'
I went through the tank for ¥70 and returned 1lIffi...
With the same control, even when the spool 19 of the valve 5 is in the push position, the ripper cylinder 16 can be driven to the heeling side.

Also, the engine stopped and the first problem occurred. 2nd pump 1°20 Even when there is no flow, the work equipment does not fall to the ground 84! However, for example, considering the case where white water acts on the side where the ripper cylinder 16 is extended, when the control valve 5 is placed in the spool I'l pull position, the return flow rate on the head side of the ripper cylinder 16 from the pipe 68 through the chamber 50, through the notch 72 of the spool 71, and from the chamber 73 to the pipe 74't.
jm, the control valve 50 communicates with the chamber 75, passes through the constriction 76 of the spool 19 in the open state, returns to the tank 111 from the tank boat chamber 77 through the piping 78. At the same time, the flow causes the notch 7 of the spool 71 to
High pressure 111 spool 71 due to the differential pressure generated before and after 2
The low pressure side is led to the pressure chamber 41 of the spool 18 through the through hole 79 of the spool 71, through the through hole 91 of the spool 71, through the passage 90 through the shuttle valve 40, and through the shuttle valve 45 to the pressure chamber of the spool 18. You are being led to a certain room 47. As a result, the spool 1g is pushed downward, and the relationship between the chambers 50 and 51 changes from closed to open. tank I1 via piping 70 to
Return to 1. As mentioned above, even if the engine is stopped, is the control valve 5f:1'? ! It is possible to switch between z<7'yb17°272- and 'L=18 when working, which is necessary for construction machinery to prevent sudden falls of working equipment (emergency braking when the engine stops). ) etc. are possible. .

As described in detail above, the present invention includes a first pump 1°, a second pump 2, and a control valve 5 that extracts pressure oil from the second pump 2 as pilot pressure and operating pressure by moving the spool 19. In response to the action from the Kotetrol valve 5, the spool 18 is operated and the combined pressure oil from the first pump 1 and the pressure oil from the second pump 2 is produced in the winding machine cylinder B. a main valve 17 that supplies oil from the working machine cylinder B to the tank 111, and a control pulp 3 that directs the pressure oil from the first pump 1 to the other working machine cylinder D; an unload valve 6 which is operated by pressure from the control valve 5 to cut off the supply of pressure oil to the control valve 3 when one working machine cylinder B is operated;
When the control pulp 3 of the working machine cylinder (I) is operated, the pilot pressure is used to operate υH+r91. A shuttle valve 5 operates to switch the pressure oil to the unload valve 6 from blocking to communication.
5.

Therefore, one of the two pumps can be used as a pilot, and the flow rate can be combined with the cylinder B and supplied to the cylinder B.
, the number of piping can be reduced. ,.

Claims (1)

[Claims] The wc1 pump 1, the second pump 2, and the control valve 5 which takes out the pressure oil from the second pump 2 as pilot pressure and operating pressure by moving the spool 19, and the operating pressure from the control valve 5. In response, the spool 18 is operated, and the confluence of the pressure oil from the first pump 1 and the pressure oil from the second pump 2 is supplied to the work machine cylinder BK, and the oil from the work machine cylinder B is discharged to the tank 111. The control valve 3 directs the pressure oil from the first pump 1 to the other work machine cylinder D, and the pilot pressure from the control valve 5 operates to operate one work machine cylinder B. Control, pressure oil supply to the control valve 3'k JJII cut off unload valve 6, control of other work machine cylinder D, pilot pressure is activated when the control valve 3 is activated, pressure to the unload valve 6 A drive circuit device for a work machine, comprising a seat valve 55 that switches oil from cutoff to communication.