JP2005232950A - Working machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a working machine which does not reduce working efficiency even in heavy work such as cutting and crushing work. <P>SOLUTION: A boom 10a and an arm 12a of a first front work arm A and a boom 10b and an arm 12b of a second front work arm B are not different in size but different in strength. The strength of the boom 10a and the arm 12a of the first front work arm A is higher than that of the boom 10b and the arm 12b of the second front work arm B. Accordingly, a higher output working tool is mounted in the first front work arm A than the second front work arm B. The weight of the first front work arm A is larger than that of the second front work arm B according to the difference in strength. The total weight of the first front work arm A and the second front work arm B is almost equal to that of left and right front work arms having the same strength as in a conventional double-arm type working machine. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a work machine having two front work arms.

  2. Description of the Related Art A double-armed work machine is known that includes articulated arms driven by a plurality of actuators on the left and right sides (see Patent Document 1).

Japanese Patent Laid-Open No. 11-181815

  The maximum mass (portable work tool mass) of the work tools that can be mounted as the left and right front work arms provided in the double-arm type work machine is substantially the same. The mass of the portable work tool of the left and right front work arms provided in the double-arm type work machine, compared to the mass of the work tool of the front work arm provided in the conventional work machine having only one front work arm. Is about ½ each. Since the mass of the work implement is proportional to the output of the work implement, the dual-arm work machine can only be mounted with a lightweight and small output implement, and in heavy work such as cutting and crushing work, work efficiency May decrease.

(1) The working machine according to the invention of claim 1 is a traveling body, a revolving body provided on the traveling body so as to be able to swivel, a first arm provided on one side in the width direction on one side in the longitudinal direction of the revolving body, The swivel body is provided on one side in the longitudinal direction and on the other side in the width direction, and includes a second arm having a length different from that of the first arm.
(2) The work machine according to the invention of claim 2 includes a traveling body, a revolving body provided on the traveling body so as to be turnable, a first arm provided on one side in the width direction on one side in the longitudinal direction of the revolving body, The swivel body is provided on one side in the longitudinal direction and on the other side in the width direction, and includes a second arm having a mass different from that of the first arm.
(3) The working machine according to the invention of claim 3 is a traveling body, a revolving body provided to be able to turn on the traveling body, a first arm provided on one side in the width direction on one side in the longitudinal direction of the revolving body, A first actuator means for driving the first arm, a second arm provided on one side in the longitudinal direction of the revolving structure on the other side in the width direction and having a mass different from that of the first arm, and a first actuator And a second actuator means for driving the second arm.
(4) The work machine according to the invention of claim 4 includes a traveling body, a swiveling body provided on the traveling body so as to be turnable, a first arm provided on one side in the width direction on one side in the longitudinal direction of the swiveling body, The first actuator means for driving the first arm, the first hydraulic circuit for operating the first actuator means at the first maximum pressure, and one side in the longitudinal direction of the revolving structure are provided on the other side in the width direction. A second arm, second actuator means for driving the second arm, and a second hydraulic circuit for operating the second actuator means at a second highest pressure different from the first highest pressure. It is characterized by that.
(5) The work machine according to the invention of claim 5 includes a traveling body, a swiveling body provided on the traveling body so as to be turnable, a first arm provided on one side in the width direction on one side in the longitudinal direction of the turning body, A second arm that is provided on one side in the longitudinal direction of the swivel body and on the other side in the width direction and has a movement locus in a vertical plane different from a movement locus in the vertical plane at the tip of the first arm; It is characterized by having.
(6) The work machine according to the invention of claim 6 includes a traveling body, a swiveling body provided on the traveling body so as to be able to turn, a first arm provided on one side in the width direction on one side in the longitudinal direction of the turning body, And a second arm provided on one side in the longitudinal direction of the swivel body on the other side in the width direction so that the overlapping range with the movement locus in the horizontal plane at the tip of the first arm is widened. And
(7) The work machine according to any one of claims 1 to 6, wherein:
One or both of the first and second arms have an articulated structure.

(1) The working machine according to the invention of claim 1 is provided on the other side in the width direction on the one side in the longitudinal direction of the swivel body, the first arm provided on the one side in the width direction on the one side in the width direction, A second arm having a length different from that of the first arm is provided. Thereby, since one arm can be made longer than the other arm, the work range of one arm is expanded and workability is improved.
(2) The work machine according to the invention of claim 2 is configured such that the first arm and the second arm have different masses. Accordingly, the strength of one arm can be made higher than that of the other arm without increasing the weight of the counterweight or increasing the size of the work machine, and a high-power work tool can be attached to one arm. Therefore, the work machine is easy to forward and can be operated in a narrow work site.
(3) The work machine according to the invention of claim 3 is configured such that the output of the actuator means is different between the first arm and the second arm. As a result, it is possible to use a work tool with a higher output than the other arm on one arm, which has a higher output of the actuator means than the other arm, enabling efficient operations such as cutting and crushing operations. it can.
(4) A work machine according to a fourth aspect of the present invention includes a first hydraulic circuit configured to operate a plurality of actuator means of the first arm at a first maximum pressure, and a plurality of actuator means of the second arm. Each arm is driven by a second hydraulic circuit that operates at a second maximum pressure different from the first maximum pressure. Thereby, it is possible to use a work tool having a simple structure and different outputs between the left and right arms.
(5) In the work machine according to the invention of claim 5, the trajectory in which the tip portion of the first arm moves in the vertical plane is different from the trajectory in which the tip portion of the second arm moves in the vertical plane. Configured. Thereby, work can be performed over a wide range of front, rear, upper and lower sides of the work implement by the first and second arms, and workability is improved.
(6) In the work machine according to the sixth aspect of the present invention, the overlapping range of the movement locus in the horizontal plane at the tip portion of the first arm and the movement locus in the horizontal plane at the tip portion of the second arm is widened. As a result, the space for collaborative work by both arms is widened and workability is improved.

――― First embodiment ―――
With reference to FIGS. 1-6, 1st Embodiment of the working machine by this invention is described. As shown in FIGS. 1 and 2, in a double-arm type work machine 100 based on a hydraulic excavator, a revolving unit 3 is attached to a traveling unit 1 so as to be able to turn. A driver's cab 4 is attached to the front of the swivel body 3. A device 5 such as a main drive device including an engine and a hydraulic pump and a counterweight 8 are provided behind the cab 4.

  A first bracket 6 a is provided in front of the right side of the cab 4, and a swing-type first front work arm A is attached to the first bracket 6 a. The first front working arm A includes a mounting body 7a that is swingably mounted in the left-right direction around a swing axis 30a (FIG. 2) provided on the first bracket 6a, and a vertical movement on the mounting body 7a. A boom 10a that is swingably attached, an arm 12a that is swingably attached to the boom 10a in a vertical direction, and a first work tool that is pivotally attached to a tip portion of the arm 12a. This is an articulated arm having a grapple 20a. The first work tool can be replaced with any one of the cutter 21a, the breaker 22a, the bucket 23a, or other work tools according to the work content.

  The first front work arm A includes a swing cylinder 9a (FIG. 2) that swings the mounting body 7a left and right, a boom cylinder 11a that swings the boom 10a up and down, an arm cylinder 13a that swings the arm 12a up and down, And a work tool cylinder 15a for rotating the grapple 20a up and down. The grapple 20a has a grapple cylinder 19a that opens and closes the grapple 20a.

  The second front work arm B is provided symmetrically with the first front work arm A across the cab 4. That is, the work machine 100 is provided with the first front work arm A and the second front work arm B on one side in the longitudinal direction and one side and the other side in the width direction, respectively. Since the second front work arm B has the same configuration as the first front work arm A, detailed description thereof is omitted. In the following description, for each component of the second front work arm B, the symbol a at the end corresponding to each component of the first front work arm A described above is described instead of b. 1 and 2, the second work tool of the second front work arm B is a grapple 20b.

  The boom 10a and arm 12a of the first front work arm A and the boom 10b and arm 12b of the second front work arm B are not different in size but different in strength. The strength of the boom 10a and the arm 12a of the first front work arm A is higher than the strength of the boom 10b and the arm 12b of the second front work arm B. Therefore, the first front work arm A can be equipped with a work tool having a higher output than the second front work arm B.

  Due to the difference in strength, the mass of the first front work arm A is larger than the mass of the second front work arm B, but the total mass of the first front work arm A and the second front work arm B is the conventional mass. It is approximately equal to the sum of the masses of the front work arms that have the same strength on the left and right as in a double-arm work machine.

  The entire length of the first front work arm A may be configured to be longer than the entire length of the second front work arm B. Thereby, the work range of the 1st front work arm A spreads, and workability | operativity improves.

  The grapple 20a of the first work tool and the grapple 20b of the second work tool use the same cylinder as the grapple cylinders 19a and 19b. However, as will be described later, the hydraulic circuit maximum pressure of the first front work arm A is the first. 2 is set higher than the pressure of the front work arm B, and the strength of the grapple 20a is increased, so that a higher output than the grapple 20b can be obtained. Further, due to the difference in strength, the grapple 20a is larger in mass than the grapple 20b.

  In general, regardless of the type of work tool, the work tool tends to increase in mass as its output increases. Further, since the cutting work and the crushing work require a larger output than the gripping work, the cutter and the breaker have a larger mass than the grabble.

  The cylinders 9a, 11a, 13a, 15a of the first front work arm A and the cylinders 9b, 11b, 13b, 15b of the second front work arm B are not different depending on the left and right front work arms, but will be described later. In addition, the set pressure of the main relief valve in the hydraulic circuit differs between the left and right front work arms.

  FIG. 3 is a diagram schematically showing hydraulic circuits 150a and 150b for driving the first front work arm A and the second front work arm B. As shown in FIG. Reference numerals 101a, 101b, and 102 denote a dual-type main pump and pilot pump driven by an engine (not shown). 103a, 104a, 105a, 106a, 107a are control valves for supplying pressure oil to the swing cylinder 9a, boom cylinder 11a, arm cylinder 13a, work tool cylinder 15a, and grapple cylinder 19a of the first front work arm A, respectively. Yes, 110a is an operating device that controls each control valve 103a to 107a to operate each cylinder, and one operating device is provided for each control valve. Reference numeral 108a denotes a main relief valve that regulates the maximum pressure of the hydraulic circuit 150a related to the first front work arm A.

  Pressure oil discharged from the main pump 101a is supplied to each hydraulic cylinder via the control valves 103a to 107a. When the operating device 110a is operated, pilot pressure oil discharged from the pilot pump 102 according to the operation amount is supplied to the corresponding control valves 103a to 107a to drive the spool. The control valves 103a to 107a supply the hydraulic oil discharged from the main pump 101a to the cylinders 9a, 11a, 13a, 15a, and 19a according to the driving amount of the spool to drive them.

  Since the hydraulic circuit 150b for driving each cylinder 9b, 11b, 13b, 15b, 19b of the second front work arm B has the same configuration as the hydraulic circuit 150a according to the first front work arm A, detailed description thereof is omitted. To do. In these hydraulic circuits 150a and 150b, the pressure oil discharged from the main pump 101a is supplied to the cylinders 9a, 11a, 13a, 15a and 19a of the first front work arm A, and is discharged from the main pump 101b. Oil is supplied to each cylinder 9b, 11b, 13b, 15b, 19b of the second front work arm B.

  As described above, the cylinders 9a, 11a, 13a, 15a, 19a of the first front work arm A and the cylinders 9b, 11b, 13b, 15b, 19b of the second front work arm B are the left and right front work arms. There is no difference. Accordingly, the set pressure of the main relief valve 108a of the hydraulic circuit 150a related to the first front work arm A is set to the hydraulic pressure related to the second front work arm B corresponding to the strength of the left and right front work arms and the output of the work tool. The pressure is set higher than the set pressure of the main relief valve 108b of the circuit 150b. That is, the set pressure of the main relief valve 108a and the set pressure of the main relief valve 108b are set to different pressure values. The set pressure of the main relief valves 108a and 108b is fixed.

  The work machine 100 described above can perform the following work. For example, as shown in FIG. 4, the work implement 100 is a cutter 21a and a grapple 20b, so that the work machine 100 can dismantle the house. As described above, since the cutting work requires a larger output than the gripping work, the cutter 21a is attached to the first front work arm A, and the grapple 20b is attached to the second front work arm B. By cutting the object to be removed while gripping it with the grapple 20b, the object to be removed can be efficiently operated without dropping.

  Moreover, as shown in FIG. 5, the work implement 100 can perform the basic dismantling work by using the breaker 22a and the grapple 20b. As described above, since the crushing operation requires a larger output than the gripping operation, the breaker 22a is attached to the first front work arm A, and the grapple 20b is attached to the second front work arm B. It is possible to work efficiently by crushing the object to be removed while collecting and loading the grapple 20b.

  FIG. 6 is a diagram illustrating a work range of the first work tool and the second work tool when the work machine 100 is viewed from above. Fan-shaped ranges 51 and 52 centering on the pivot shafts 30a and 30b are work ranges of the first work tool and the second work tool. The hatched portion 53 in which the fan-shaped ranges 51 and 52 are overlapped is a range in which the work can be performed by both the first work tool and the second work tool, that is, the movement locus in the horizontal plane at the tip portion of the first work tool, 2 It is the overlapping range with the movement locus in the horizontal plane at the tip portion of the work implement.

  In order to prevent the front work arms A and B from interfering with the cab 4 provided in the center of the work machine 100 in the left-right direction, the left and right swing shafts 30 a and 30 b are provided in front of the cab 4. It has been. That is, the front work arms A and B are provided in front of the work machine 100 so as not to interfere with other parts of the work machine 100 when swung in the left-right direction around the rocking shaft centers 30a and 30b. ing. As a result, the swing range of the first front work arm A in the left direction and the swing range of the second front work arm B in the right direction are expanded, so that both front work arms A and B can perform cooperative work. Space that can be expanded.

  For example, as shown in FIG. 4, with respect to a vertically arranged structure such as a pillar, the upper part of the pillar to be removed is gripped by the grapple 20 b of the second front work arm B while the first front work arm A is It can be disassembled by cutting with the cutter 21a. In this way, it is possible to efficiently dismantle the pillars extending in the vertical direction.

The working machine 100 according to the first embodiment described above has the following operational effects.
(1) The strength of the boom 10a and the arm 12a of the first front work arm A is configured to be higher than the strength of the boom 10b and the arm 12b of the second front work arm B. As a result, since the first front work arm A can be used with a work tool having a larger output than the second front work arm B, work with heavy loads such as cutting work and crushing work can be performed efficiently.

(2) Although the mass of the first front work arm A is different from the mass of the second front work arm B, the sum of the mass of the first front work arm A and the mass of the second front work arm B is Like the arm type work machine, it was configured to be substantially equal to the sum of the masses of the front work arms having the same strength on the left and right. Therefore, since it is possible to attach a high-output work tool without increasing the mass of the counterweight 8 or increasing the size of the revolving structure 3, the work machine 100 can be easily transported and can be operated in a narrow work site. It becomes possible.

(3) Corresponding to the outputs of the left and right work tools, the set pressure of the main relief valve 108a of the hydraulic circuit 150a related to the first front work arm A is changed to the main relief of the hydraulic circuit 150b related to the second front work arm B. It is set higher than the set pressure of the valve 108b. Accordingly, it is possible to use work tools having different outputs with the left and right front work arms with a simple structure.

(4) The front work arms A and B are provided in front of the work machine 100 so that they do not interfere with other parts of the work machine 100 when swung in the left-right direction around the rocking axes 30a and 30b. It has been. As a result, the swing range of the first front work arm A in the left direction and the swing range of the second front work arm B in the right direction are expanded, so that both front work arms A and B can perform cooperative work. The space that can be widened, and workability is improved. Further, since the left and right pivot shafts 30a and 30b are provided in front of the cab 4, the left and right visibility in the cab 4 is improved and safety is increased.

――― Second embodiment ―――
With reference to FIGS. 7 and 8, a second embodiment of the working machine equipped with the operating device according to the present invention will be described. In the following description, the same components as those in the first embodiment are denoted by the same reference numerals, and different points will be mainly described. Points that are not particularly described are the same as those in the first embodiment. FIG. 7 is a perspective view of the working machine according to the second embodiment. The work machine 200 is different from the work machine 100 of the first embodiment in that an auxiliary post 16a is mounted between the attachment body 7a and the boom 10a.

  The auxiliary post 16a is a member for moving the working range of the first front working arm A upward. Accordingly, the auxiliary post 16a attached to the attachment body 7a can swing in the left-right direction around the swing axis 30a (see FIG. 2) together with the first front work arm A. The hatched portions 61 and 62 shown in FIG. 8 indicate the respective work ranges of the first front work arm A and the second front work arm B when the work machine 200 is viewed from the side, that is, the front work arms A and B. This is a range in which the tip of each work tool mounted on the can be moved. The hatched portion 63 is a movable range of the distal end portion of the work tool in one front work machine having a vehicle grade similar to that of the work machine 200.

  As shown in FIG. 8, the movement trajectory (movable range) in the vertical plane at the distal end portion of the first work implement attached to the first front work arm A is the second work attached to the second front work arm B. It differs from the movement locus (movable range) in the vertical plane at the tip of the tool. That is, the movable range (shaded portion 61) of the tip portion of the first work tool attached to the first front work arm A is the movable range (the shaded portion 61) of the tip portion of the second work tool attached to the second front work arm B. The movable range is raised by the height of the auxiliary post 16a with respect to the hatched portion 62). As a result, the work range by the work machine 200 is a combination of the hatched portion 61 and the hatched portion 62, so that the front end portion of the work tool in the one-front work machine having the same grade as the work machine 200 is obtained. It has a range equivalent to the movable range (shaded portion 63).

In the work machine 200 of the second embodiment described above, first, in addition to the functions and effects of the embodiment, the following functions and effects are achieved.
(1) The auxiliary post 16a is mounted between the attachment body 7a and the boom 10a, and the movable range of the tip portion of the first work tool mounted on the first front work arm A is determined by the height of the auxiliary post 16a. Only raised. Thereby, the work range by the 1st front work arm A and the 2nd front work arm B becomes equivalent to the movable range of the front-end | tip part of the work tool in the 1 front work machine which has a vehicle grade comparable as the work machine 200. Therefore, work can be performed over a wide range of front, rear, upper and lower, and workability is improved.

――― Modifications ――――
(1) In the above description, the strength of the first front work arm A is higher than the strength of the second front work arm B, but the strength of the second front work arm B is higher than the strength of the first front work arm A. Thus, a high-output work tool may be attached to the second front work arm B.
(2) In the above description, the set pressures of the main relief valves 108a and 108b are fixed, but the present invention is not limited to this. You may enable it to change the pressure setting value of a main relief valve according to the output of the working tool with which it mounts | wears.

(3) In the above description, the setting pressures of the main relief valves 108a and 108b are set to different pressure values so as to correspond to the strength of the front work arm and the output of the work tool which are different on the left and right. Is not limited to this. For example, the set pressure may be made equal, and the thrust corresponding to the strength of the front work arm may be obtained by changing the diameter of each cylinder that drives the front work arm to the left and right with the front work arm. Further, the main pump 101a that supplies pressure oil to the cylinders of the first front work arm A and the cylinders of the second front work arm B so as to correspond to the strength of the front work arms and the output of the work tool that are different on the left and right. You may mutually change the capacity | capacitance of the main pump 101b which supplies pressure oil.

(4) In the second embodiment, the auxiliary post 16a is mounted between the attachment body 7a on the right side of the work implement and the boom 10a, but the present invention is not limited to this. An auxiliary post may be mounted between the attachment body 7b on the left side of the work implement and the boom 10b, or an auxiliary post may be mounted on both the left and right sides of the work implement.

(5) In the above description, the left and right front work arms have the same size, but the present invention is not limited to this. For example, you may comprise so that the magnitude | size of an arm or a boom may differ with one front work arm and the other front work arm. Further, as shown in FIG. 9, a telescopic front work arm C can be attached. Further, the sum of the masses of the left and right front work arms may not be substantially equal to the sum of the right and left masses of the front work arms having the same strength on the left and right as in a conventional work machine, and the unweight 8 needs to be replaced. As long as it is not in the range.
(6) The above-described embodiments and modifications may be combined.

(7) FIG. 10 is a modification of the hydraulic circuit of FIG. 3 and shows a so-called load sensing hydraulic circuit. The hydraulic circuit shown in FIG. 10 includes a hydraulic circuit 400A for the first front work arm A and a hydraulic circuit 500B for the second front work arm B. The maximum set pressure of the hydraulic circuit 400A is set higher than the maximum set pressure of the hydraulic circuit 500B.

  The hydraulic circuit 400A will be described. The hydraulic circuit 400 </ b> A is driven by the variable displacement hydraulic pump 401 driven by the prime mover 404, the boom hydraulic cylinder 411 that is driven by the discharge oil from the hydraulic pump 401 to raise and lower the boom, and the discharge oil from the hydraulic pump 401. The arm hydraulic cylinder 412 that drives the arm, the boom control valve 421 that controls the direction and flow rate of pressure oil to the boom hydraulic cylinder 411, and the direction and flow rate of pressure oil to the arm hydraulic cylinder 412 Arm control valve 422 for controlling the control. Each control valve is provided with meter-in throttles a1 and a2, respectively, so that the load pressure downstream of the control valve is taken out from the control valve.

  Although not shown, a hydraulic cylinder (for example, the hydraulic cylinder 15a in FIG. 1) that swings the work tool at the end of the arm, a hydraulic actuator (for example, the hydraulic cylinder 19a in FIG. 1) that drives the work tool, Two control valves for controlling the direction and flow rate of pressure oil to the actuator are also included in the hydraulic circuit 400A.

  A high pressure selection valve 402 detects the maximum load pressure of the boom and arm hydraulic cylinders. The hydraulic circuit 400A includes a high pressure selection valve 403 and two high pressure selection valves in addition to the high pressure selection valve 402, and the maximum pressure of the four hydraulic actuators described above is selected as the load sensing pressure from the high pressure selection valve 402. Is done. Reference numeral 405 denotes a differential pressure compensator that adjusts the displacement volume of the variable displacement hydraulic pump 401 so that the differential pressure between the discharge pressure of the hydraulic pump 401 and the maximum load pressure (load sensing pressure) becomes a predetermined value.

The differential pressure compensator 405 includes a compensator valve 4051 and a compensator piston 4052. The differential pressure between the load-sensing pressure Pamax and the pump pressure P _P detected by the maximum pressure selection valve is, in more than the set value is set by the spring 4051a of the compensator valve 4051, compensator valve 4051 compensator piston 4052 switched to Lee position the pump pressure P _P is introduced, the tilting amount of the variable displacement hydraulic pump 401 is increased. The differential pressure between the load-sensing pressure Pamax and the pump pressure P _P is less than the set value set by the spring 4051a of the compensator valve 4051, compensator valve 4051 tank pressure compensator piston 4052 switched to B position is introduced, The amount of tilting of the variable displacement hydraulic pump 401 decreases.

The hydraulic circuit 400A includes a boom pressure compensation valve (flow control valve) 431 that controls a flow rate passing through the control valve 421 so that the differential pressure across the boom control valve 421 becomes a reference value, and an arm control valve. A pressure compensation valve for arm (flow control valve) 432 for controlling the flow rate passing through the control valve 422 so that the differential pressure across the front and rear of the valve 422 becomes a reference value; a main relief valve 406 for setting the maximum pressure of the hydraulic circuit 400A; An unload valve 407 is provided for allowing oil discharged from the hydraulic pump 401 to escape to the tank when the four actuators are not used. Reference numeral 408 denotes an anti-saturation valve. When the differential pressure between the maximum load pressure detected with the pump pressure P _P is equal to or greater than the set value set by the spring 408a, anti-saturation valve 408 is the pressure P _C to be described later switched to the b position and the tank pressure, the pressure difference There has been a function of the pressure P _C and the pump pressure P _P switched to b position becomes less than the set value.

The load sensing system configured in this way controls the discharge volume of the variable displacement hydraulic pump 401 so that the differential pressure between the pump pressure and the actuator maximum load pressure becomes a reference value determined by the spring 4051a. Therefore, the maximum pressure among the load pressures P _L 1, P _L 2... Of each actuator is taken out as the load sensing pressure Pamax by the high pressure selection valves 402, 403,. It switched in accordance with the differential pressure between the discharge pressure _{P P} 401.

When (pump pressure P _P -load sensing pressure Pamax) is equal to or higher than the reference value set by the spring 4051a, the compensator valve 4051 is switched in the direction of the position A according to the differential pressure. The pump tilting angle led the pump pressure P _P in the compensator piston 4052 by Lee position the pump delivery rate is increased larger. On the other hand, when the differential pressure is less than the pressure set by the spring 4051a, the compensator valve 4051 is switched to the low position, and the compensator piston 4052 is connected to the tank. As a result, the pump tilt angle is reduced and the pump discharge flow rate is reduced.

On the other hand, in FIG. 10, the pressures P _L 1, P _L 2... Downstream of the corresponding control valves 421, 422. The spring 431a, the differential pressure ΔP of the control valve 421 ...... by the spring force _{F K} of 432a is defined. The pressure P _Z 1, P _Z 2... Upstream of the corresponding control valve 421, 422... Is introduced to the pilot port on the right side of each pressure compensation valve, and the pressure P _C is supplied by the anti-saturation valve 408. Led. The pressure P _C is the tank pressure when the anti-saturation valve 408 Guy position, when the B position is the pump pressure P _P.

  Therefore, each of the pressure compensating valves 431, 432,... Opens fully when the following equation (1) is satisfied, and according to the pressure difference between the left and right pilot ports when the equation (2) is satisfied in that state. The drive is controlled so that the opening is reduced.

P _L 1 + ΔP ≧ P _Z 1 + P _C (1)
P _L 2 + ΔP ≧ P _Z 2 + P _C (1)
P _L 1 + ΔP <P _Z 1 + P _C (2)
P _L 2 + ΔP <P _Z 2 + P _C (2)

Now, when the hydraulic cylinder 411, 412 ...... are combined operation, when the load pressure P _L 1 of the hydraulic cylinder 411 is the maximum, the discharge capacity of the hydraulic pump 401, the load pressure of the pump pressure _{P P} and the hydraulic cylinder 411 The pressure difference with P _L 1 is adjusted so as to be the set pressure of the spring 4051a. On the other hand, the pressure relationship led to the left and right pilot ports of the pressure compensating valves 431, 432,... Is as follows.

P _L 1 + ΔP≈P _Z 1 + P _C (3)
P _L 2 + ΔP <P _Z 2 + P _C (3)

Thus, upstream of the pressure compensating valve 431 of the control valve 421 of the hydraulic cylinder 411 is not squeezed, the upstream pressure compensating valve 432 ...... control valve 422 ...... other hydraulic cylinder 412 ...... load pressure P _L 2 ...... It is squeezed according to.

With the above operation, the load sensing system, as the differential pressure between the maximum load pressure Pamax discharge pressure P _P and the actuator of the hydraulic pump 401 becomes equal to the reference value of the load sensing control, the pump delivery rate is controlled . Further, even if each control valve 421, 422... Is operated simultaneously and the attachment, boom, and arm are combined, each actuator is not affected by the load fluctuation of the other actuator, and the corresponding control valve 421, The oil discharged from the hydraulic pump 401 is divided according to the opening ratio of 422.

Furthermore, when the sum of the flow rates required by each actuator exceeds the pump discharge flow rate, the opening of the pressure compensation valve other than the pressure compensation valve of the actuator with the maximum load pressure is the difference between the load pressure and the maximum load pressure. Therefore, the pump discharge oil does not flow into the low load side, and the oil amount is distributed according to the opening ratio.

  The above is the description of the hydraulic circuit 400A of the first front work arm A, but the operation of the second front work arm B in the hydraulic circuit 500B is the same except that the maximum set pressure is set lower than that of the hydraulic circuit 400A. Therefore, the description is omitted. That is, the work can be performed with the output of the first front work arm A larger than the output of the second front work arm B.

(8) In the above description, the crawler type traveling body and the working machine having the revolving body installed so as to be able to turn on the traveling body have been described. However, the tire type traveling body and the suspension on the traveling body in a non-turnable state. The present invention can also be applied to a wheel-type work vehicle (work machine) having a vehicle body frame installed via an apparatus.

  For example, when an object to be taken out is buried under the rubble or a person falls down, the upper rubble is held by one of the first and second front work arms A and B, and the other arm The present invention can also be applied to a special vehicle for rescue (work machine) that takes out an object or rescues a person. In such a rescue special vehicle, when supporting the debris, the first and second front work arms A and B, that is, the double arms support the debris so that the load is not concentrated on one point, thereby preventing the debris from collapsing. You can Alternatively, when the irregular rubble is pushed away, if it is pressed with two arms, the handling becomes stable and the rubble can be efficiently removed. Furthermore, as another example of this type of wheel work vehicle, a special work machine in which a telescopic work device and an articulated arm such as an aerial work device are attached as two arms can be assumed.

  In the civil engineering machine shown in FIG. 1 or the like, the breaker work can be performed while holding the amorphous object with one arm by the cooperative operation of the two arms. Alternatively, two long objects may be supported and transported while being balanced.

  In the above embodiment and its modifications, the first and second arms are connected to the first front work arm A, the second front work arm B, and the third front work arm C, and the first and second hydraulic circuits. Corresponds to hydraulic circuits 150a and 150b and 400A and 500B, respectively. Also, for example, the cylinders 9a, 11a, 13a, 15a, 19a of the first front work arm A are the first actuator means, and the cylinders 9b, 11b, 13b, 15b, 19b of the second front work arm B are the second. Respectively corresponding to the actuator means. Furthermore, as long as the characteristic functions of the present invention are not impaired, the present invention is not limited to the device configuration in the above-described embodiment.

It is a perspective view of working machine 100 of a 1st embodiment by the present invention. 1 is a plan view of a work machine 100. FIG. It is a figure which shows the hydraulic circuit which drives the 1st front work arm A and the 2nd front work arm B. It is a figure which shows the demolition work of the house by the working machine. It is a figure which shows the basic dismantling work by the working machine. It is a figure which shows the working range of a 1st working tool and a 2nd working tool when the working machine 100 is seen from the upper surface. It is a perspective view of the working machine 200 of 2nd Embodiment. It is a figure which shows each work range of the 1st front work arm A and the 2nd front work arm B when the working machine 200 is seen from the side. It is a perspective view of the working machine 300 which is a modification of this invention. FIG. 6 is a diagram showing another example of a hydraulic circuit that drives the first front work arm A and the second front work arm B.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Traveling body 3 Revolving body 4 Cab 9a, 9b Swing cylinder 10a, 10b Boom 11a, 11b Boom cylinder 12a, 12b Arm 13a, 13b Arm cylinder 15a, 15b Work tool cylinder 16a Auxiliary post 19a, 19b Grapple cylinder 20a, 20b Grapples 30a, 30b Oscillating shafts 51, 52 Range 53 Shaded parts 61, 62, 63 Shaded parts 100, 200, 300 Work machines 101a, 101b Main pumps 103a-107a, 103b-107b Control valves 108a, 108b Main relief valves
150a, 150b, 400A, 500B Hydraulic circuit A First front work arm B Second front work arm C Front work arm

Claims (7)

A traveling body,
A swiveling body provided on the traveling body so as to be turnable;
A first arm provided on one side in the longitudinal direction of the swivel body on one side in the width direction;
A working machine comprising: a second arm provided on one side in the longitudinal direction of the revolving structure and on the other side in the width direction, and having a length different from that of the first arm. A traveling body,
A swiveling body provided on the traveling body so as to be turnable;
A first arm provided on one side in the longitudinal direction of the swivel body on one side in the width direction;
A working machine comprising: a second arm that is provided on one side in the longitudinal direction of the revolving body and on the other side in the width direction, and has a mass different from that of the first arm. A traveling body,
A swiveling body provided on the traveling body so as to be turnable;
A first arm provided on one side in the longitudinal direction of the swivel body on one side in the width direction;
First actuator means for driving the first arm;
A second arm provided on one side in the longitudinal direction of the swivel body on the other side in the width direction and having a mass different from that of the first arm;
A working machine comprising: second actuator means that has an output different from the output of the first actuator and drives the second arm. A traveling body,
A swiveling body provided on the traveling body so as to be turnable;
A first arm provided on one side in the longitudinal direction of the swivel body on one side in the width direction;
First actuator means for driving the first arm;
A first hydraulic circuit for operating the first actuator means at a first maximum pressure;
A second arm provided on one side in the longitudinal direction of the revolving structure on the other side in the width direction;
Second actuator means for driving the second arm;
A working machine comprising: a second hydraulic circuit that operates the second actuator means at a second highest pressure different from the first highest pressure. A traveling body,
A swiveling body provided on the traveling body so as to be turnable;
A first arm provided on one side in the longitudinal direction of the swivel body on one side in the width direction;
A second arm that is provided on one side in the longitudinal direction of the revolving structure and on the other side in the width direction and has a movement locus in a vertical plane that is different from a movement locus in a vertical plane at the tip of the first arm. A working machine characterized by comprising A traveling body,
A swiveling body provided on the traveling body so as to be turnable;
A first arm provided on one side in the longitudinal direction of the swivel body on one side in the width direction;
A second arm provided on one side in the longitudinal direction of the swivel body on the other side in the width direction so that an overlapping range with the movement locus in the horizontal plane at the tip of the first arm is widened; A working machine characterized by In the working machine as described in any one of Claims 1-6,
One or both of the first and second arms have a multi-joint structure.

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