JP2015040575A - Multiple direction selector valve of construction machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a multiple direction selector valve capable of stopping speed increase of a first actuator without the addition of external piping when a second actuator is operated.SOLUTION: A boom speed increase valve 4 having a speed increase position 4a in which pressure oil from a second pump 52 is supplied to a boom hydraulic cylinder 55 and a neutral position 4b in which the pressure oil from the second pump 52 is not supplied to the boom hydraulic cylinder 55 is arranged in a valve element block 10. A boom speed increase release mechanism for returning the boom speed increase valve 4 from the speed increase position 4a to the neutral position 4b when an arm direction selector valve 2z is operated is provided in the valve element block 10.

Description

  The present invention relates to a multiple direction switching valve for moving a plurality of hydraulic actuators attached to a construction machine such as a hydraulic excavator.

  For example, Patent Document 1 discloses a multi-directional directional switching valve of this type. In the multiple direction switching valve (hydraulic circuit) described in Patent Document 1, when the boom direction switching valve 5a is operated in the boom raising direction, the boom speed increasing direction switching valve 14a is simultaneously switched, and the first hydraulic pump Pressure oil is supplied from 1 and the second hydraulic pump 2 to the boom cylinder 5 (boom acceleration).

  At this time, when the arm direction switching valve 8a is further operated and the arm cylinder 8 is moved, the pressure oil is continuously supplied from the second hydraulic pump 2 to the boom cylinder 5 (boom acceleration is maintained).

JP 2004-324208 A

  Here, in order to stop the boom acceleration when the arm direction switching valve 8a is operated, as one method, a signal that the arm direction switching valve 8a is operated is sent as a signal to the boom speed increasing direction switching valve 14a. It is conceivable that the boom speed increasing direction switching valve 14a is returned to its neutral position by being inserted from the outside (outside the multiple direction switching valve). However, this method has a problem that external piping is additionally required.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to stop the acceleration of the first actuator when the second actuator is operated without adding external piping. It is to provide a multiple directional control valve.

  The present invention includes a first circuit in which a first directional switching valve is disposed and pressure oil is supplied from a first pump, and a second circuit in which a second directional switching valve is disposed and pressure oil is supplied from a second pump. Is a multiple direction switching valve for a construction machine formed in the valve body block, wherein the first direction switching valve is a valve for controlling supply and discharge of pressure oil from the first pump to the first actuator. The second direction switching valve is a valve that controls supply and discharge of pressure oil from the second pump to the second actuator. A first actuator speed increasing valve having a speed increasing position for supplying pressure oil from the second pump to the first actuator and a neutral position for not supplying pressure oil from the second pump to the first actuator; A first actuator acceleration release mechanism that is disposed in the valve block and switches the first actuator acceleration valve from the acceleration position to the neutral position when the second direction switching valve is operated; It is provided in the body block.

  The present invention also includes a first circuit in which a first direction switching valve is arranged and pressure oil is supplied from the first pump, and a second circuit in which a second direction switching valve is arranged and pressure oil is supplied from the second pump. A circuit and a third circuit in which a third direction switching valve is disposed and pressure oil is supplied from a third pump is a multiple direction switching valve for a construction machine formed in a valve body block, The one-way switching valve is a valve that controls the supply and discharge of pressure oil from the first pump to the first actuator, and the second direction switching valve is the supply of pressure oil from the second pump to the second actuator. The third direction switching valve is a valve that controls supply and discharge of pressure oil from the third pump to the third actuator. A first actuator that switches the flow of pressure oil from the third pump to the first actuator to the flow of pressure oil from the third pump to the second actuator when the second direction switching valve is operated. An acceleration release mechanism is provided in the valve body block.

  The above-mentioned two inventions have unity of the invention in that a first actuator speed increase release mechanism that operates when the second direction switching valve is operated is provided in the valve body block.

  According to the multiple direction switching valve of the present invention, the acceleration of the first actuator can be stopped when the second actuator is operated without adding external piping.

1 is a hydraulic circuit diagram illustrating a multiple direction switching valve according to a first embodiment of the present invention. It is a hydraulic circuit diagram which shows the modification of the multiple direction switching valve shown in FIG. It is a hydraulic circuit diagram which shows the multiple direction switching valve which concerns on 2nd Embodiment of this invention. FIG. 4 is a hydraulic circuit diagram showing a modification of the multiple direction switching valve shown in FIG. 3.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. In addition, although embodiment as a multiple direction switching valve for hydraulic excavators is shown below, the multiple direction switching valve of the present invention can also be applied to construction machines other than hydraulic excavators.

(First embodiment)
<Configuration of multiple direction switching valve>
As shown in FIG. 1, the hydraulic excavator to which the multiple direction switching valve 101 is applied includes three pumps (hydraulic pumps) 51, 52, and 53. These three pumps 51, 52, and 53 are driven by, for example, an engine (not shown). The hydraulic excavator includes hydraulic actuators such as two traveling hydraulic motors 54 and 57, a boom hydraulic cylinder 55, a bucket hydraulic cylinder 56, an arm hydraulic cylinder 59, a turning hydraulic motor 60, and a dozer hydraulic cylinder 61. Can be installed where needed. An optional actuator 58 (service) may be attached to the excavator.

Here, the left traveling hydraulic motor 54, the boom hydraulic cylinder 55, and the bucket hydraulic cylinder 56 are respectively a left traveling direction switching valve 1x, a boom direction switching valve 1y, and a boom direction switching valve 1y, which are arranged in the first circuit A, respectively. This is a first actuator whose operation is controlled by the bucket direction switching valve 1z. Each of these directional control valves is a hydraulic pilot type spool valve and is sometimes called a control valve (the same applies to other directional control valves described later). Pressure oil is mainly supplied from the first pump 51 to each directional control valve (first circuit A) arranged in the first circuit A.
Each of the left traveling direction switching valve 1x, the boom direction switching valve 1y, and the bucket direction switching valve 1z is a first direction switching valve.

The right traveling hydraulic motor 57, the actuator 58, and the arm hydraulic cylinder 59 are respectively a right traveling direction switching valve 2x, a service direction switching valve 2y, and an arm direction switching valve 2z disposed in the second circuit B. The second actuator whose operation is controlled by. Pressure oil is mainly supplied from the second pump 52 to each direction switching valve (second circuit B) arranged in the second circuit B.
The right traveling direction switching valve 2x, the service direction switching valve 2y, and the arm direction switching valve 2z are respectively second direction switching valves.

Further, the turning hydraulic motor 60 and the dozer hydraulic cylinder 61 are controlled by the turning direction switching valve 3x and the dozer direction switching valve 3y arranged in the third circuit C, respectively. It is. Pressure oil is supplied from the third pump 53 to the turning direction switching valve 3x (third circuit C). Pressure oil is mainly supplied from the third pump 53 to each direction switching valve (third circuit C) arranged in the third circuit C.
Each of the turning direction switching valve 3x and the dozer direction switching valve 3y is a third direction switching valve.

  Each direction switching valve (1x to 1z, 2x to 2z, 3x to 3y) and each circuit (A, B, C) are provided in the valve body block 10.

[Boom acceleration valve (first actuator acceleration valve)]
Here, the boom speed-up valve 4 (first actuator speed-up valve) that speeds up the operation of raising the boom by supplying pressure oil from the second pump 52 to the cylinder chamber 55a on the boom raising side of the boom hydraulic cylinder 55. ) Is arranged in the second circuit B in the valve body block 10.

  The boom speed increasing valve 4 is disposed downstream of the arm direction switching valve 2z in the unload passage 32 extending from the second pump 52 to the tank T. In addition, you may arrange | position the boom speed-up valve 4 in the unload channel | path 32 in the upstream of the direction switching valve 2z for arms.

  The configuration of the boom acceleration valve 4 will be described. The boom speed increasing valve 4 is a three-position hydraulic pilot type spool valve, and has a speed increasing position 4a and a neutral position 4b. The speed increasing position 4a is a position for supplying the pressure oil from the second pump 52 to the cylinder chamber 55a on the boom raising side of the boom hydraulic cylinder 55, and the neutral position 4b is a position for supplying the pressure oil from the second pump 52 to the boom. This is a position where the hydraulic cylinder 55 is not supplied. The boom speed increasing valve 4 is integrally provided with a sub valve 8. A pilot port 9a (pilot chamber 9a) is disposed on one side of the boom acceleration valve 4, and a pilot port 9b (pilot chamber 9b) is disposed on the other side (on the sub valve 8 side).

  When the pilot pressure is not introduced into any of the pilot ports 9a and 9b, the boom speed increasing valve 4 is in the neutral position 4b. When pilot pressure is introduced into the pilot port 9a, the position is switched to the acceleration position 4a. When the pilot pressure is introduced into the pilot port 9b in a state where the pilot pressure is introduced into the pilot port 9a, the boom acceleration valve 4 is switched. Returns from the acceleration position 4a to the neutral position 4b.

  A boom raising pilot line 25 to which a boom operation signal (pilot pressure) for raising the boom is introduced is connected to the pilot port 9a of the boom speed increasing valve 4.

[Joint valve]
In the valve body block 10, a merging valve 5 that supplies pressure oil from the third pump 53 to the first direction switching valve and / or the second direction switching valve is provided.

  The merging valve 5 is a three-position hydraulic pilot spool valve, and has a neutral position 5a, an arm merging position 5b (arm and service merging position), and a running position 5c (running independent position). First and second pilot ports 10a and 10b are arranged on one side of the merging valve 5, and a spring 10c is arranged on the other side.

  In a state where pilot pressure is not introduced into any of the first to second pilot ports 10a and 10b, the merging valve 5 is in the neutral position 5a by the elastic force of the spring 10c. When the pilot pressure is introduced into the first pilot port 10a, the joining valve 5 is switched to the arm joining position 5b, and when the pilot pressure is introduced into the second pilot port 10b, the joining valve 5 is switched to the traveling position 5c.

  A boom lowering pilot line 26 to which a boom operation signal (pilot pressure) for lowering the boom is introduced is connected to the first pilot port 10a of the junction valve 5. A pilot line 21 (travel independent signal pilot passage) for travel independent signal (pilot pressure) connected to the pilot pump 62 is connected to the second pilot port 10 b of the junction valve 5.

  Here, the pilot line 22 (pilot passage) is connected to the pilot pump 62 in a form branched from the pilot line 21. A side bypass line 24 is connected to the pilot line 21 downstream of the branch position of the pilot line 22 from the pilot line 21. The pilot line 21 and the pilot line 22 are provided with a stop 21a and a stop 22a, respectively.

  The pilot line 22 passes through the sub valve 8 linked to the boom speed increasing valve 4 and the sub valves 7z and 7y linked to the arm / service direction switching valves 2z and 2y in this order. Is connected to a drain line 27 communicating with.

  The side bypass line 24 passes through the sub-valves 7x, 6x, 6y, and 6z that are linked to the directional control valves 2x, 1x, 1y, and 1z for right running, left running, boom, and bucket, respectively, in this order. On the downstream side, it is connected to a drain line 27 communicating with the tank T.

  The boom accelerating valve 4 and the sub-valves 8, 7x, 6x of the directional switching valves 2x, 1x for right traveling and left traveling are respectively positioned at the boom accelerating valve 4 and the directional switching valves 2x, 1x. Regardless of the direction, the sub valve 7z, 7y, 6y, 6z of the directional switching valves 2z, 2y, 1y, and 1z for the arm, service, boom, and bucket use the directional switching valves 2z, 2y, and 2z. 1y and 1z are configured to be opened at the neutral position and closed at the operating position.

[Boom acceleration release mechanism (first actuator acceleration release mechanism)]
Here, in the valve element block 10, when the arm direction switching valve 2z (second direction switching valve) is operated, the boom speed increasing valve 4 is switched (returned) from the speed increasing position 4a to the neutral position 4b. A boom acceleration cancellation mechanism (first actuator acceleration cancellation mechanism) is provided.

  The boom acceleration release mechanism includes a sub-valve 7z interlocked with the arm direction switching valve 2z, a pilot line 22 connected to the pilot pump 62, and the boom acceleration valve 4 (boom) on the upstream side of the sub-valve 7z of the pilot line 22. It is composed of a speed increase cancellation signal line 23 (speed increase cancellation signal passage) connected to the pilot port 9b of the sub valve 8) interlocked with the speed increase valve 4.

<Operation, action, and effect of multiple direction switching valve>
(1) Boom single raising operation When a boom single boom raising operation is performed, a boom operation signal (pilot pressure) for raising the boom is transmitted from the pilot line 25 to the boom direction switching valve 1y and the boom speed increasing valve 4. It is introduced into the pilot port 9a. Thereby, the boom speed increasing valve 4 is switched from the neutral position 4b to the speed increasing position 4a, and the pressure oil from the second pump 52 is increased in the cylinder chamber 55a on the boom raising side of the boom hydraulic cylinder 55. Supplied from the passage 33. As a result, pressure oil is supplied from the first pump 51 and the second pump 52 to the boom hydraulic cylinder 55 (boom acceleration).

  In the present embodiment, the portion to which the speed increasing pressure oil is supplied from the second pump 52 is the supply / discharge passage 34 outside the valve body block 10 with respect to the boom hydraulic cylinder 55, but the second pump The portion to which the speed increasing pressure oil from 52 is supplied may not be the supply / discharge passage 34 (the same applies to modified examples and other embodiments described later).

  For example, the location where the speed increasing pressure oil from the second pump 52 is supplied is upstream of the boom direction switching valve 1 y in the unload passage 31 of the first pump 51, and the first pump 51. It may be an unload passage 31 portion through which pressure oil flows from the boom hydraulic cylinder 55 to the boom hydraulic cylinder 55.

  Further, the portion to which the speed increasing pressure oil from the second pump 52 is supplied may be the supply / discharge passage 35 in the valve element block 10 with respect to the boom hydraulic cylinder 55.

  When the speed increasing pressure oil from the second pump 52 is supplied as the unload passage 31 of the first pump 51 or the supply / discharge passage 35 in the valve body block 10 with respect to the boom hydraulic cylinder 55, The speed increasing passage 33 can be formed only in the valve body block 10. By forming the speed increasing passage 33 only in the valve body block 10, external piping can be reduced (the same applies to modified examples and other embodiments described later).

(2) Boom single raising operation + arm operation Here, when the arm direction switching valve 2z is operated during the boom single raising operation, the sub valve 7z interlocked with the arm direction switching valve 2z is closed, The sub valve 7z shuts off the pilot line 22. Thereby, the upstream side of the sub valve 7z in the pilot line 22 becomes a pilot pressure. Thereby, the pilot pressure is introduced from the acceleration release signal line 23 to the pilot port 9b of the boom acceleration valve 4 (the sub valve 8 linked to the boom acceleration valve 4). As a result, the boom acceleration valve 4 returns from the acceleration position 4a to the neutral position 4b.

  As a result, the pressure oil from the second pump 52 is not supplied to the boom hydraulic cylinder 55, and the boom hydraulic cylinder 55 operates with the pressure oil from the first pump 51 (boom acceleration stop). At this time, since the merging valve 5 is in the arm merging position 5b, the arm hydraulic cylinder 59 is operated by the pressure oil from the second pump 52 and the third pump 53.

(3) Actions / Effects According to the multiple direction switching valve 101 of the present embodiment, the boom acceleration canceling mechanism is configured in the valve body block 10, so that the arm hydraulic cylinder 59 is not added without adding external piping. When the (second actuator) is operated, the speed increase of the boom hydraulic cylinder 55 (first actuator) can be stopped.

  It is to be noted that not the boom operation signal but the bucket operation signal (pilot pressure) is introduced into the pilot port 9a of the speed increasing valve 4, and the hydraulic oil from the speed increasing valve 4 is supplied to the boom hydraulic cylinder 55. If the passage is configured to be supplied to the bucket hydraulic cylinder 56, the speed increasing mechanism constituted by the sub valve 7z, the pilot line 22 and the speed increasing cancel signal line 23 (speed increasing cancel signal path) It becomes a speed release mechanism. That is, the first actuator acceleration release mechanism of the multiple direction switching valve of the present invention may be a bucket acceleration release mechanism instead of the boom acceleration release mechanism shown in the present embodiment (the modification examples described later and The same applies to other embodiments).

  In the above-described operation of the multiple direction switching valve, an example is described in which the boom acceleration is stopped when the arm direction switching valve 2z is operated (the arm is operated) during the boom single raising operation. Also, when the service direction switching valve 2y is operated (service is operated) during the boom single raising operation, the boom acceleration valve 4 returns from the acceleration position 4a to the neutral position 4b. Stops (the same applies to modified examples and other embodiments described later).

  That is, according to the multiple direction switching valve of the present invention, when the second actuator is operated by the first actuator acceleration release mechanism provided in the valve block without adding external piping, The speed increase can be stopped.

  Here, the boom acceleration cancellation mechanism (first actuator acceleration cancellation mechanism) of the present embodiment uses the sub valve 7z interlocked with the arm direction switching valve 2z (second direction switching valve) as one component of the mechanism. Used. By using the sub-valve linked to the second direction switching valve, it is easy to generate a speed increase cancellation signal for returning the boom speed increasing valve 4 (first actuator speed increasing valve) from the speed increasing position 4a to the neutral position 4b.

  In the present embodiment, the pilot line 22 that is a component of the boom speed increasing / disengaging mechanism (first actuator speed increasing / releasing mechanism) is connected to the traveling independent signal pilot path (pilot line 21) connected to the pilot pump 62. Branched. By diverging the pilot line 22 from the existing pilot line 21, the enlargement of the valve body block 10 can be suppressed.

(Modification)
A multiple direction switching valve 102 according to a modification of the first embodiment will be described with reference to FIG. A main difference between the first embodiment shown in FIG. 1 and the modification shown in FIG. 2 is a branching point (upstream end) of the pilot line 22. The configuration (circuit configuration) of the merging valve 5 is slightly different between the first embodiment shown in FIG. 1 and the modification shown in FIG. 2, but the description thereof will be omitted. The functions at the neutral position 5a of the merging valve 5 shown in FIG. 2, the arm merging position 5b (arm and service merging position), and the traveling position 5c (running independent position) are the functions of the merging valve 5 shown in FIG. It is almost the same as the function.

  First, a pilot line 25 (joint switching signal pilot passage) for joining switching signal (pilot pressure) connected to the pilot pump 62 is connected to the first pilot port 10a of the joining valve 5 in this modification.

  In this modification, the pilot line 22 (pilot passage) is connected to the pilot pump 62 in a form branched from the pilot line 25. The pilot line 25 is provided with a diaphragm 25a.

  The boom acceleration cancellation mechanism (first actuator acceleration cancellation mechanism) in this modification is the same as in the first embodiment, the sub valve 7z interlocking with the arm direction switching valve 2z, and the pilot line 22 connected to the pilot pump 62. And an acceleration cancellation signal line 23 (acceleration cancellation signal path) for connecting the upstream side of the sub valve 7z of the pilot line 22 to the pilot port 9b of the boom acceleration valve 4 (sub valve 8 linked to the boom acceleration valve 4); Consists of.

<Action and effect>
The movement of each part of the multiple direction switching valve 102 in the boom acceleration at the time of the boom independent raising operation and the boom independent lifting operation + the boom acceleration stop at the time of the arm operation is the same as that of the multiple direction switching valve 101 of the first embodiment. Since it is the same as the movement of each part, the description is omitted.

  In this modification, the pilot passage is a pilot line that is a component of the boom acceleration release mechanism (first actuator acceleration release mechanism) from the merge switching signal pilot passage (pilot line 25) connected to the pilot pump 62. 22 is branched. By diverging the pilot line 22 from the existing pilot line 25, the enlargement of the valve body block 10 can be suppressed.

(Second Embodiment)
<Configuration of multiple direction switching valve>
The multiple direction switching valve 103 of the second embodiment will be described with reference to FIG. The difference between the modification of the first embodiment shown in FIG. 2 and the second embodiment shown in FIG. 3 is the position of the speed increasing valve 4. In the present embodiment, the speed increasing valve 4 is disposed in the third circuit C in the valve body block 10.

  The speed increasing valve 4 is disposed on the downstream side of the turning direction switching valve 3x in the unload passage 36 extending from the third pump 53 to the tank T. The speed increasing valve 4 may be arranged in the unload passage 36 upstream of the turning direction switching valve 3x or upstream of the dozer direction switching valve 3y.

  The speed increasing valve 4 is a three-position hydraulic pilot type spool valve, and has a speed increasing position 4a and a second speed increasing position 4b. The second acceleration position 4b is also a neutral position. The speed increasing position 4 a is a position for supplying pressure oil from the third pump 53 to the cylinder chamber 55 a on the boom raising side of the boom hydraulic cylinder 55, and the second speed increasing position 4 b is a pressure from the third pump 53. This is the position where oil is supplied to the second actuator (arm hydraulic cylinder 59, actuator 58 (service)) via the merging valve 5. The speed increasing valve 4 is integrally provided with a sub valve 8. A pilot port 9a is disposed on one side of the speed increasing valve 4, and a pilot port 9b (pilot chamber 9b) is disposed on the other side (on the sub valve 8 side).

  In a state where the pilot pressure is not introduced into any of the pilot ports 9a and 9b, the speed increasing valve 4 is in the second speed increasing position 4b. When pilot pressure is introduced into the pilot port 9a, the position is switched to the acceleration position 4a. When the pilot pressure is introduced into the pilot port 9b while the pilot pressure is introduced into the pilot port 9a, the acceleration valve 4 is The speed increasing position 4a returns to the second speed increasing position 4b.

  A boom raising pilot line 25 to which a boom operation signal (pilot pressure) for raising the boom is introduced is connected to the pilot port 9a of the speed increasing valve 4.

  Here, in the valve body block 10, when the arm direction switching valve 2z (second direction switching valve) is operated, the pressure oil from the third pump 53 to the boom hydraulic cylinder 55 (first actuator). Is provided with a boom speed increasing release mechanism (first actuator speed increasing releasing mechanism) for switching the flow of the flow to the flow of pressure oil from the third pump 53 to the arm hydraulic cylinder 59 (second actuator).

  In the case of this embodiment, the boom acceleration release mechanism (first actuator acceleration release mechanism) increases the acceleration valve 4 when the arm direction switching valve 2z (second direction switching valve) is operated. The position is switched (returned) from the position 4a to the second acceleration position 4b.

  The boom speed increasing release mechanism includes a sub valve 7z linked to the arm direction switching valve 2z, a pilot line 22 connected to the pilot pump 62, and a speed increasing valve 4 (speed increasing) on the upstream side of the sub valve 7z of the pilot line 22. The speed increasing cancellation signal line 23 (speed increasing cancellation signal passage) connected to the pilot port 9b of the sub valve 8) interlocked with the valve 4 is constituted.

<Operation, action, and effect of multiple direction switching valve>
(1) Boom independent raising operation When a boom independent raising operation is performed, a boom operation signal (pilot pressure) for raising the boom is transmitted from the pilot line 25 to the boom direction switching valve 1y and the speed increasing valve 4 pilot. Introduced into port 9a. As a result, the speed increasing valve 4 is switched from the second speed increasing position 4b to the speed increasing position 4a, and the pressure oil from the third pump 53 is placed in the cylinder chamber 55a on the boom raising side of the boom hydraulic cylinder 55. It is supplied from the speed increasing passage 33. As a result, pressure oil is supplied from the first pump 51 and the third pump 53 to the boom hydraulic cylinder 55 (boom acceleration).

(2) Boom single raising operation + arm operation Here, when the arm direction switching valve 2z is operated during the boom single raising operation, the sub valve 7z interlocked with the arm direction switching valve 2z is closed, The sub valve 7z shuts off the pilot line 22. Thereby, the upstream side of the sub valve 7z in the pilot line 22 becomes a pilot pressure. Thereby, the pilot pressure is introduced from the acceleration release signal line 23 to the pilot port 9b of the acceleration valve 4 (the sub valve 8 linked to the acceleration valve 4). As a result, the boom acceleration valve 4 returns from the acceleration position 4a to the second acceleration position 4b.

  As a result, the pressure oil from the second pump 52 is not supplied to the boom hydraulic cylinder 55, and the boom hydraulic cylinder 55 operates with the pressure oil from the first pump 51 (boom acceleration stop). At this time, since the merging valve 5 is in the arm merging position 5b, the arm hydraulic cylinder 59 is operated by the pressure oil from the second pump 52 and the third pump 53.

(3) Action / Effect According to the multiple direction switching valve 103 of the present embodiment, the boom acceleration canceling mechanism is configured in the valve body block 10, so that the arm hydraulic cylinder 59 is not added without adding external piping. When the (second actuator) is operated, the speed increase of the boom hydraulic cylinder 55 (first actuator) can be stopped.

  That is, according to the multiple direction switching valve of the present invention, when the second actuator is operated by the first actuator acceleration release mechanism provided in the valve block without adding external piping, The speed increase can be stopped.

  As described above, in this embodiment, the speed increasing valve 4 is disposed in the third circuit C in the valve body block 10. Since other configurations are the same as those of the multiple direction switching valves 101 and 102 of the first embodiment and its modifications, the multiple direction switching valve 103 of the present embodiment is also the same as the multiple direction switching valves 101 and 102. It has the effect of.

  In the present embodiment, as in the modification of the first embodiment, the pilot line 22 (pilot passage) is connected to the pilot pump 62 in a form branched from the pilot line 25 (joint switching signal pilot passage) connected to the pilot pump 62. ), But, as in the first embodiment, the boom speed increasing release mechanism (first actuator speed increasing) is connected from the pilot line 21 (travel independent signal pilot path, see FIG. 1) connected to the pilot pump 62. The pilot line 22 which is one component of the release mechanism may be branched.

(Modification)
A multiple direction switching valve 104 according to a modification of the second embodiment will be described with reference to FIG. In the second embodiment shown in FIG. 3 and the modification shown in FIG. 4, when the second direction switching valve is operated, the first actuator speed increase release mechanism provided in the valve body block 10 4 is common in that the flow of pressure oil from the third pump 53 to the first actuator is switched to the flow of pressure oil from the third pump 53 to the second actuator. In the modification example, the second embodiment shown in FIG. 3 is different from the modification example shown in FIG. 4 in that a valve dedicated to speed increase is not provided. In the multiple direction switching valve 104 shown in FIG. 4, the merging valve 5 has the function of the speed increasing valve 4 shown in FIG. That is, the merging valve 5 also serves as the speed increasing valve 4 and is a speed increasing and merging valve. The merging valve 5 can also be understood as a speed increasing valve having a merging valve function.

  As shown in FIG. 4, the merging valve 5 is a four-position hydraulic pilot type spool valve, and includes an acceleration position 5a, a neutral position 5b, an arm merging position 5c (arm and service merging position), And a position 5d (travel independent position). One of the merging valves 5 is provided with first and second two pilot ports 10a and 10b, and the other is provided with a pilot port 10d for increasing the first actuator speed.

  The speed increasing position 5a is a position for supplying the pressure oil from the third pump 53 to the cylinder chamber 55a on the boom raising side of the boom hydraulic cylinder 55, and the arm joining position 5c is the pressure oil from the third pump 53. This is the position to be supplied to the second actuator (arm hydraulic cylinder 59, actuator 58 (service)). In addition, it can also be grasped that the arm joining position 5c is the second acceleration position of the acceleration valve 4 in the second embodiment. That is, the arm joining position 5c corresponds to the second acceleration position of the acceleration valve 4 in the second embodiment.

  In a state where pilot pressure is not introduced into any of the pilot ports 10a, 10b, and 10d, the merging valve 5 is in the neutral position 5b. When pilot pressure is introduced into the pilot port 10d, the position is switched to the acceleration position 5a. When the pilot pressure is introduced into the first pilot port 10a in a state where the pilot pressure is introduced into the pilot port 10d, the merging valve 5 Switches from the acceleration position 5a to the arm joining position 5c.

  When pilot pressure is introduced into the first pilot port 10a in a state where pilot pressure is not introduced into the pilot port 10d, the merging valve 5 is switched from the neutral position 5b to the arm merging position 5c. Further, when the pilot pressure is introduced to the second pilot port 10b, the merging valve 5 is switched to the traveling position 5d.

  A boom raising pilot line 25 to which a boom operation signal (pilot pressure) for raising the boom is introduced is connected to the pilot port 10d of the merging valve 5.

  In the case of this modification, the boom acceleration cancellation mechanism (first actuator acceleration cancellation mechanism) is operated when the arm direction switching valve 2z (second direction switching valve) is operated while the boom raising operation is performed. Then, the merging valve 5 is switched from the acceleration position 5a to the arm merging position 5c.

  This boom acceleration release mechanism is composed of a sub valve 7z interlocked with the arm direction switching valve 2z and a pilot line 22 connected to the pilot pump 62. The pilot line 22 is connected to the pilot pump 62 in a form that branches from the pilot line 25 (joint switching signal pilot passage) connected to the pilot pump 62.

  Note that, as in the first embodiment, one configuration of the boom acceleration release mechanism (first actuator acceleration release mechanism) from the pilot line 21 connected to the pilot pump 62 (running independent signal pilot passage, see FIG. 1). The pilot line 22 as an element may be branched.

<Operation, action, and effect of multiple direction switching valve>
(1) Boom single raising operation When a boom single boom raising operation is performed, a boom operation signal (pilot pressure) for raising the boom is sent from the pilot line 25 to the boom direction switching valve 1y and the pilot port of the junction valve 5. 10d. As a result, the merging valve 5 is switched from the neutral position 5b to the speed increasing position 5a, and pressure oil from the third pump 53 is supplied to the speed increasing passage 37 in the cylinder chamber 55a on the boom raising side of the boom hydraulic cylinder 55. Supplied from As a result, pressure oil is supplied from the first pump 51 and the third pump 53 to the boom hydraulic cylinder 55 (boom acceleration).

(2) Boom single raising operation + arm operation Here, when the arm direction switching valve 2z is operated during the boom single raising operation, the sub valve 7z interlocked with the arm direction switching valve 2z is closed, The sub valve 7z shuts off the pilot line 22. Thereby, the upstream side of the sub valve 7z in the pilot line 22 becomes a pilot pressure. Thereby, a pilot pressure is introduced into the first pilot port 10a of the merging valve 5. As a result, the merging valve 5 is switched from the acceleration position 5a to the arm merging position 5c.

  As a result, the pressure oil from the third pump 53 is not supplied to the boom hydraulic cylinder 55, and the boom hydraulic cylinder 55 operates with the pressure oil from the first pump 51 (boom acceleration stop). At this time, the arm hydraulic cylinder 59 operates with pressure oil from the second pump 52 and the third pump 53.

(3) Action / Effect According to the multiple direction switching valve 104 of the present modification, the valve body block 10 can be further prevented from being enlarged by using the valve having both the speed increasing valve function and the merging valve function. .

1x: Left traveling direction switching valve (first direction switching valve)
1y: Boom direction switching valve (first direction switching valve)
1z: Bucket direction switching valve (first direction switching valve)
2x: Direction switch valve for right travel (second direction switch valve)
2y: Service direction switching valve (second direction switching valve)
2z: Direction switching valve for arm (second direction switching valve)
3x: Direction switching valve for turning (third direction switching valve)
3y: Dozer direction switching valve (third direction switching valve)
4: Boom speed increasing valve (first actuator speed increasing valve)
4a: Speed increasing position 4b: Neutral position 5: Junction valve 10: Valve body block 51: First pump 52: Second pump 53: Third pump 54: Left traveling hydraulic motor (first actuator)
55: Boom hydraulic cylinder (first actuator)
56: Hydraulic cylinder for bucket (first actuator)
57: Right running hydraulic motor (second actuator)
58: Actuator (second actuator)
59: Hydraulic cylinder for arm (second actuator)
60: Hydraulic motor for turning (third actuator)
61: Hydraulic cylinder for dozer (third actuator)
101: Multiple direction switching valve A: First circuit B: Second circuit C: Third circuit

Claims (9)

A first circuit in which a first direction switching valve is arranged and pressure oil is supplied from a first pump;
A second circuit in which a second directional control valve is arranged and pressure oil is supplied from a second pump;
Is a multiple direction switching valve for construction machinery formed in the valve block,
The first direction switching valve is a valve that controls supply and discharge of pressure oil from the first pump to the first actuator;
The second direction switching valve is a valve that controls supply and discharge of pressure oil from the second pump to the second actuator,
A first actuator speed increasing valve having a speed increasing position for supplying pressure oil from the second pump to the first actuator and a neutral position for not supplying pressure oil from the second pump to the first actuator; Placed in the valve block,
A first actuator acceleration release mechanism for switching the first actuator acceleration valve from the acceleration position to the neutral position when the second direction switching valve is operated is provided in the valve block; A multi-directional directional control valve for construction machinery. In the multiple direction switching valve of the construction machine according to claim 1,
The first actuator acceleration release mechanism is
A sub-valve interlocking with the second direction switching valve;
A pilot passage connected to the pilot pump;
A speed increasing cancellation signal path connecting the upstream side of the sub valve of the pilot path to the pilot port of the first actuator speed increasing valve;
The sub valve shuts off the pilot passage when the second directional control valve is operated, whereby the upstream side of the sub valve becomes a pilot pressure, so that the first actuator speed increasing valve is moved from the speed increasing position. A multi-directional directional control valve for a construction machine, which switches to the neutral position. In the multiple direction switching valve for the construction machine according to claim 2,
The multi-directional directional control valve for a construction machine, wherein the pilot passage branches off from a traveling independent signal pilot passage connected to the pilot pump. In the multiple direction switching valve for the construction machine according to claim 2,
The multiple direction switching valve for a construction machine, wherein the pilot passage is branched from a pilot passage for a merging switching signal connected to the pilot pump. A first circuit in which a first direction switching valve is arranged and pressure oil is supplied from a first pump;
A second circuit in which a second directional control valve is arranged and pressure oil is supplied from a second pump;
A third circuit in which a third direction switching valve is arranged and pressure oil is supplied from a third pump;
Is a multiple direction switching valve for construction machinery formed in the valve block,
The first direction switching valve is a valve that controls supply and discharge of pressure oil from the first pump to the first actuator;
The second direction switching valve is a valve that controls supply and discharge of pressure oil from the second pump to the second actuator,
The third direction switching valve is a valve that controls supply and discharge of pressure oil from the third pump to the third actuator,
A first actuator that switches the flow of pressure oil from the third pump to the first actuator to the flow of pressure oil from the third pump to the second actuator when the second direction switching valve is operated. A multiple direction switching valve for a construction machine, wherein an acceleration release mechanism is provided in a valve block. In the multiple direction switching valve of the construction machine according to claim 5,
A speed increasing valve having a speed increasing position for supplying pressure oil from the third pump to the first actuator and a second speed increasing position for supplying pressure oil from the third pump to the second actuator; Placed in the valve block,
When the second direction switching valve is operated, the speed increasing valve is switched from the speed increasing position to the second speed increasing position by the first actuator speed increasing release mechanism. Multiple direction switching valve. In the multiple direction switching valve of the construction machine according to claim 6,
The first actuator acceleration release mechanism is
A sub-valve interlocking with the second direction switching valve;
A pilot passage connected to the pilot pump;
A speed increasing cancellation signal path connecting the upstream side of the sub valve of the pilot path to the pilot port of the speed increasing valve;
The sub valve shuts off the pilot passage when the second directional control valve is operated, whereby the upstream side of the sub valve becomes a pilot pressure, so that the speed increasing valve is moved from the speed increasing position to the second speed. A multi-directional directional control valve for a construction machine, which is switched to an acceleration position. In the multiple direction switching valve of the construction machine according to claim 7,
The multi-directional directional control valve for a construction machine, wherein the pilot passage branches off from a traveling independent signal pilot passage connected to the pilot pump. In the multiple direction switching valve of the construction machine according to claim 7,
The multiple direction switching valve for a construction machine, wherein the pilot passage is branched from a pilot passage for a merging switching signal connected to the pilot pump.

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