JP2021008739A - Work machine - Google Patents

Abstract

To provide a work machine for enabling effective assist when an engine requires the assist.SOLUTION: A work machine includes a machine body, an engine provided on the machine body, a motor generator which operates as a motor to perform assist operation to assist the drive of the engine and operates as a generator with the power of the engine to perform power generation operation to generate power, a hydraulic driving device to which the power of the engine and the motor generator can be transmitted, an operation member for operating the hydraulic driving device, and a control device for setting a timing for the assist operation on the basis of the transition of an engine speed after operating the operation member.SELECTED DRAWING: Figure 15

Description

The present invention relates to working machines such as compact truck loaders and skid steer loaders.

Conventionally, Patent Document 1 is known as a hybrid type working machine having an engine and a motor / generator in a working machine such as a compact truck loader. In the work machine of Patent Document 1, when the excavation work is expected to increase the output of the hydraulic pump, the work mode is set to the first mode, and the output of the hydraulic pump is slightly lower than the excavation state. In the case of, the work mode is set to the second mode, and the assist operation is determined by the motor generator according to each of the first mode and the second mode.

International Publication No. 2014/136834

In Patent Document 1, the assist operation is determined according to the work of the working machine. However, the assist operation may be performed even though the engine has spare capacity.
The present invention has been made to solve such problems of the prior art, and an object of the present invention is to provide a working machine capable of effectively assisting when the engine requires assistance. ..

The working machine of the present invention includes a machine body, an engine provided in the machine body, an assist operation that operates as a motor to assist the driving of the engine, and a power generation operation that operates as a generator by the power of the engine to generate power. A motor generator to be operated, a hydraulic drive device capable of transmitting the power of the engine and the motor generator, an operating member for operating the hydraulic drive device, and a transition of the rotation speed of the engine after operating the operating member. It is provided with a control device for setting the timing of the assist operation based on the above.

When performing the assist operation, the control device performs the assist operation after the engine speed changes from rising to falling.
The work machine includes an operation valve that sets a pilot pressure according to the operation of the operation member, and the output of the hydraulic drive device changes according to the pilot pressure set by the operation valve.
The work machine includes a pair of traveling devices provided on the machine body and a pair of traveling motors for driving the pair of traveling devices, and the hydraulic drive device includes a pair of traveling devices for driving the pair of traveling motors. It is a pump.

The control device starts the assist operation when the turning speed when the aircraft is turned by the pair of traveling devices is increased and the engine speed is increased and then decreased.

According to the present invention, when the engine needs assist, the assist can be effectively performed.

It is an overall side view of a working machine. It is a perspective view of the aircraft. It is a perspective view which shows the arrangement of a device (device). It is sectional drawing of the inside of a rotary electric machine. It is a figure which shows the hydraulic system of a traveling system. It is a figure which shows the hydraulic system of a work system. It is a figure which shows the relationship between an engine speed, a running primary pressure, and a setting line. It is a figure which shows the control block diagram in a working machine. It is a figure which shows an example of the control map. It is a figure which shows an example of the work operation amount BD, BU when the work operation member is operated. It is a figure which shows an example of the work operation amount SU, SD when the work operation member is operated. It is a figure which shows an example of the 1st switching line L31, L32. It is a figure which shows an example of the 2nd switching lines L33, L34. It is a figure which shows the operation of changing the 1st rotation speed N1 and the 2nd rotation speed N2 when the work operation member is operated. It is a figure which shows the operation of changing the 1st rotation speed N1 and the 2nd rotation speed N2 when the work operation member and the traveling operation member are operated. It is a figure which shows an example of the 3rd switching lines L35, L36. It is a figure which shows the other operation of changing the 1st rotation speed N1 and the 2nd rotation speed N2 when the traveling operation member is operated. It is a figure which shows the relationship between the transition M10 of the engine rotation speed E1 and the turning speed V10. It is a figure which shows the operation of setting the timing of an assist operation.

Hereinafter, embodiments of the working machine according to the present invention will be described with reference to the drawings.
FIG. 1 shows a side view of the working machine 1 according to the present invention. FIG. 1 shows a compact truck loader as an example of a working machine. However, the working machine according to the present invention is not limited to the compact truck loader, and may be, for example, another type of loader working machine such as a skid steer loader. Further, it may be a work machine other than the loader work machine. In the present invention, the front side (left side of FIG. 1) of the driver seated in the driver's seat of the work machine is the front, the rear side of the driver (right side of FIG. 1) is the rear, and the left side of the driver (front of FIG. 1). The side) will be described as the left side, and the driver's right side (the back side in FIG. 1) will be described as the right side. The directions orthogonal to the front and rear of the airframe may be described as the airframe width direction (width direction).

The working machine 1 includes a machine body 2, a working device 3, and a pair of traveling devices 4L and 4R.
A cabin 5 is mounted on the upper part and the front part of the aircraft 2. The rear portion of the cabin 5 is swingably supported by a bracket of the airframe 2 around a support shaft. The front part of the cabin 5 can be mounted on the front part of the aircraft 2. A driver's seat 7 is provided in the cabin 5.
The pair of traveling devices 4L and 4R are composed of a crawler type traveling device. The traveling device 4L is provided on one side (left side) of the machine body 2, and the traveling device 4R is provided on the other side (right side) of the machine body 2.

The working device 3 has a boom 10, a boom cylinder 14, a working tool cylinder 15, and a working tool 11. The boom 10 is supported by a lift link 12 and a control link 13. A boom cylinder 14 composed of a double-acting pressure cylinder is provided between the base side of the boom 10 and the rear lower portion of the machine body 2. By simultaneously expanding and contracting the boom cylinder 14, the boom 10 swings up and down. Mounting brackets 18 are pivotally supported on the tip side of the boom 10 so as to be rotatable around a horizontal axis, and the back side of the work tool 11 is attached to the mounting brackets 18 provided on the left and right sides. That is, the work tool 11 is attached to the tip of the boom 10.

Further, a work tool cylinder 15 made of a double-acting hydraulic cylinder is interposed between the mounting bracket 18 and the intermediate portion on the tip end side of the boom 10. The work tool 11 swings (squeeze dump operation) due to the expansion and contraction of the work tool cylinder 15.
The work tool 11 is detachable from the mounting bracket 18. The work tool 11 is, for example, an attachment (spare attachment) such as a bucket, a hydraulic crusher, a hydraulic breaker, an angle bloom, an earth auger, a pallet fork, a sweeper, a mower, or a snow blower.

Next, the aircraft will be described.
As shown in FIG. 2, the machine body 2 has a right frame portion 20, a left frame portion 21, a front frame portion 22, a bottom frame portion 23, and an upper frame portion 24.
The right frame portion 20 constitutes the right portion of the airframe 2. The left frame portion 21 constitutes the left portion of the airframe 2. The front frame portion 22 constitutes the front portion of the machine body 2, and connects the front portions of the right frame portion 20 and the left frame portion 21 to each other. The bottom frame portion 23 constitutes the bottom portion of the machine body 2, and connects the lower portions of the right frame portion 20 and the left frame portion 21 to each other. The upper frame portion 24 constitutes an upper portion of the machine body 2 near the rear portion, and connects the upper portion of the right frame portion 20 and the upper portion of the left frame portion 21 near the rear portion.

The rear portions of the right frame portion 20 and the left frame portion 21 swingably support the boom 10 and the like. The right frame portion 20 and the left frame portion 21 are provided with a track frame 25 and a motor mounting portion 26.
As shown in FIG. 3, the airframe 2 is provided with an engine 60, a cooling fan 61, a radiator, a motor generator 63, and a hydraulic drive device 64. The engine 60 is an internal combustion engine such as a diesel engine or a gasoline engine. The cooling fan 61 is a cooling fan driven by the power of the engine 60, and the radiator cools the cooling water of the engine 60. The motor generator 63 is a device that performs an assist operation that operates as a motor to assist the driving of the engine 60 and a power generation operation that operates as a generator by the power of the engine 60 to generate electricity. The motor generator 63 is a motor generator, and a permanent magnet-embedded three-phase AC synchronous motor is adopted as a drive type.

The hydraulic drive device 64 is a device that is driven by the power of the engine 60 and / or the motor generator 63, and mainly outputs power for work. The hydraulic drive device 64 is provided in front of the motor generator 63. The hydraulic drive device 64 includes a plurality of hydraulic pumps. For example, as shown in FIGS. 5 and 6, the plurality of hydraulic pumps include a traveling pump 52L, a traveling pump 52R, a sub pump P1, and a main pump P2. And is included.

Further, the machine body 2 is provided with a battery 66 and a power control device 67. The battery 66 charges the electric power generated by the motor generator 63, and supplies the charged electric power to the motor generator 63 and the like.
The work machine 1 drives the hydraulic drive device 64 with the power of the engine 60, drives the hydraulic drive device 64 with both the engine 60 and the motor generator 63, or operates the motor generator 63 with the power of the engine 60. It is possible to generate electricity. That is, the power transmission of the working machine is a parallel hybrid type. The power transmission structure of the engine 60 and the motor generator 63 will be described.

As shown in FIGS. 3 and 4, a housing 65 for accommodating a substantially disk-shaped flywheel and a motor generator 63 is provided at the front portion of the engine 60. The motor generator 63 includes a connecting portion 63a connected to the flywheel, a rotor 63b fixed to the connecting portion 63a, a stator 63c provided on the rotor 63b, and a water jacket 63d provided on the outside of the stator 63c. have.

The connecting portion 63a is formed in a tubular shape, and the rear end thereof is attached to the flywheel. An intermediate shaft 68a is provided inside the connecting portion 63a. A coupling 68b is provided at the rear end of the intermediate shaft 68a, and the outside of the coupling 68b is connected to the flywheel. Further, the drive shaft of the hydraulic drive device 64 is connected to the front end of the intermediate shaft 68a.
Therefore, when the engine 60 is driven, the rotational power of the crankshaft (output shaft) 60a of the engine 60 is transmitted to the flywheel to rotate the flywheel. As shown by the arrow F1 in FIG. 4, the rotational power of the flywheel is transmitted from the coupling 68b to the intermediate shaft 68a, and then transmitted from the intermediate shaft 68a to the drive shaft of the hydraulic drive device 64, and the hydraulic drive device concerned. 64 can be driven.

Further, as shown by the arrow F2 in FIG. 4, the rotational power of the flywheel is transmitted to the rotor 63b via the connecting portion 63a. Therefore, the motor generator 63 can be operated as a generator by transmitting the rotational power of the engine 60 to the rotor 63b (connecting portion 63a). On the other hand, the rotor 63b can be rotated by supplying the electric power stored in the battery 66 to the stator 63c. As shown by the arrow F3, the rotational power of the rotor 63b can be transmitted to the flywheel via the connecting portion 63a. Therefore, the motor generator 63 can be operated as an electric motor to assist the engine 60.

5 and 6 show a hydraulic circuit (hydraulic system) of a working machine. FIG. 5 is a traveling system hydraulic system, and FIG. 6 is a working system hydraulic system.
As shown in FIG. 5, the traveling system hydraulic system is a system that operates the traveling devices 4L and 4R by the hydraulic pressure when the hydraulic drive device 64 is driven. The traveling system hydraulic system includes a sub-pump P1 which is a hydraulic pump for discharging hydraulic oil, a first traveling motor mechanism 31L, a second traveling motor mechanism 31R, and a traveling drive mechanism 34.

The sub pump P1 is composed of a constant capacity type gear pump. The sub pump P1 can discharge the hydraulic oil stored in the tank (hydraulic oil tank). A discharge oil passage 40 for flowing hydraulic oil is provided on the discharge side of the sub pump P1. A first charge oil passage 41 is connected to the discharge side of the discharge oil passage 40. The first charge oil passage 41 reaches the traveling drive mechanism 34. Of the hydraulic oil discharged from the sub pump P1, the hydraulic oil used for control may be referred to as pilot oil, and the pressure of the pilot oil may be referred to as pilot pressure.

The travel drive mechanism 34 is a mechanism for driving the first travel motor mechanism 31L and the second travel motor mechanism 31R, and is a drive circuit (left drive circuit) 34L for driving the first travel motor mechanism 31L and a second travel. It has a drive circuit (right drive circuit) 34R for driving the motor mechanism 31R.
The drive circuits 34L and 34R have traveling pumps 52L and 52R, transmission oil passages 57h and 57i, and a second charge oil passage 42, respectively. The shifting oil passages 57h and 57i are oil passages that connect the traveling pumps 52L and 52R and the traveling motors 36L and 36R. The second charge oil passage 42 is an oil passage that is connected to the transmission oil passages 57h and 57i and replenishes the hydraulic oil from the sub pump P1 to the transmission oil passages 57h and 57i. The traveling pumps 52L and 52R are swash plate type variable displacement axial pumps driven by the power of the engine 60. The traveling pumps 52L and 52R have a pressure receiving portion 52a and a pressure receiving portion 52b on which a pilot pressure acts, and the angle of the swash plate is changed by the pilot pressure acting on the pressure receiving portions 52a and 52b. By changing the angle of the diagonal plate, the output (discharge amount of hydraulic oil) of the traveling pumps 52L and 52R and the discharge direction of the hydraulic oil can be changed. In other words, the traveling pumps 52L and 52R change the driving force output to the traveling devices 4L and 4R by changing the angle of the swash plate.

The first traveling motor mechanism 31L is a mechanism for transmitting power to the drive shaft of the traveling device 4L provided on the left side of the machine body 2. The second traveling motor mechanism 31R is a mechanism for transmitting power to the drive shaft of the traveling device 4R provided on the right side of the machine body 2. The first traveling motor mechanism 31L has traveling motors 36L and 36R and a speed change mechanism.
The traveling motors 36L and 36R are, for example, swash plate type variable capacitance axial motors. The traveling motor 36L is attached to the motor mounting portion 26 on the left frame portion 21 side, and transmits traveling power to the traveling device 4L. The traveling motor 36R is attached to the motor mounting portion 26 on the right frame portion 20 side, and transmits traveling power to the traveling device 4R. The traveling motors 36L and 36R are motors capable of changing the vehicle speed (rotation) to the first speed or the second speed. In other words, the traveling motors 36L and 36R are motors capable of changing the propulsive force of the working machine 1, that is, the traveling devices 4L and 4R.

The speed change mechanism includes a swash plate switching cylinder 38a and a traveling switching valve 38b. The swash plate switching cylinder 38a is a cylinder that changes the angle of the swash plate of the traveling motors 36L and 36R by expanding and contracting. The traveling switching valve 38b is a valve that expands and contracts the swash plate switching cylinder 38a to one side or the other side, and is a two-position switching valve that switches between the first position 39a and the second position 39b. The traveling switching valve 38b is switched by the speed change switching valve 44. The speed change valve 44 is connected to the discharge oil passage 40 and is connected to the travel switching valve 38b of the first traveling motor mechanism 31L and the traveling switching valve 38b of the second traveling motor mechanism 31R. The speed change valve 44 is a two-position switching valve that can switch between the first position 44a and the second position 44b. When the speed change valve 44 is set to the first position 44a, the pressure of the hydraulic oil acting on the travel switching valve 38b of the speed change mechanism is set to a predetermined speed (for example, 1st speed). Further, when the speed change switching valve 44 is set to the first position 44a, the pressure of the hydraulic oil acting on the traveling switching valve 38b is set to a speed (second speed) faster than a predetermined speed (first speed). Therefore, when the speed change switching valve 44 is in the first position 44a, the traveling switching valve 38b becomes the first position 39a, and the swash plate switching cylinder 38a contracts accordingly to set the traveling motors 36L and 36R to the first speed. be able to. When the speed change switching valve 44 is in the second position 44b, the traveling switching valve 38b is in the second position 39b, and the swash plate switching cylinder 38a is extended accordingly to set the traveling motors 36L and 36R to the second speed. be able to. The 1st or 2nd speed of the traveling motors 36L and 36R is controlled by the work control device 70. For example, the work control device 70 is provided with an operation member 58 such as a switch (shift switch) (see FIG. 8). When the operation member 58 is switched to the first speed, the work control device 70 outputs a control signal for degaussing the solenoid of the shift switching valve 44 to set the shift switching valve 44 to the first position 44a. Further, when the operation member 58 is switched to the second speed, the work control device 70 outputs a control signal for exciting the solenoid of the shift switching valve 44 to set the shift switching valve 44 to the second position 44b.

As shown in FIG. 5, the working machine 1 includes an operating device 53. The operating device 53 is a device that operates the traveling devices 4L and 4R, that is, the first traveling motor mechanism 31L, the second traveling motor mechanism 31R, and the traveling drive mechanism 34. The operation device 53 includes a traveling operation member 54 and a plurality of operation valves 55 (55a, 55b, 55c, 55d). The plurality of operating valves 55 (55a, 55b, 55c, 55d) are traveling operating valves.

The traveling operation member 54 is an operation member that is supported by the operation valve 55 and swings in the left-right direction (body width direction) or in the front-rear direction. Further, the plurality of operation valves 55 are operated in common, that is, by one traveling operation member 54. The plurality of operation valves 55 operate based on the swing of the traveling operation member 54. The hydraulic oil (pilot oil) from the sub pump P1 can be supplied to the plurality of operating valves 55 via the discharge oil passage 40. The plurality of operating valves 55 are an operating valve 55a, an operating valve 55b, an operating valve 55c, and an operating valve 55d.

The plurality of operating valves 55 and the traveling drive mechanism 34 (traveling pumps 52L, 52R) of the traveling system are connected by a traveling oil passage 45. The traveling oil passage 45 has a first traveling oil passage 45a, a second traveling oil passage 45b, a third traveling oil passage 45c, a fourth traveling oil passage 45d, and a fifth traveling oil passage 45e. The first traveling oil passage 45a is an oil passage connected to a pressure receiving portion (first pressure receiving portion) 52a of the traveling pump 52L. The second traveling oil passage 45b is an oil passage connected to the pressure receiving portion (second pressure receiving portion) 52b of the traveling pump 52L. The third traveling oil passage 45c is an oil passage connected to the pressure receiving portion (third pressure receiving portion) 52a of the traveling pump 52R. The fourth traveling oil passage 45d is an oil passage connected to the pressure receiving portion (fourth pressure receiving portion) 52b of the traveling pump 52R. The fifth traveling oil passage 45e is an oil passage connecting the operation valve 55, the first traveling oil passage 45a, the second traveling oil passage 45b, the third traveling oil passage 45c, and the fourth traveling oil passage 45d. The fifth traveling oil passage 45e connects a plurality of shuttle valves 46 and a plurality of operating valves 55 (55a, 55b, 55c, 55d).

When the traveling operation member 54 is swung forward (in the direction of arrow A1 in FIG. 5), the operation valve 55a is operated and the pilot pressure is set by the operation valve 55a, which is set in the pressure receiving portion 52a of the traveling pumps 52L and 52R. The swash plate of the traveling pumps 52L and 52R is tilted from the neutral position to the normal rotation side by the action of the pilot pressure, so that the traveling pumps 52L and 52R discharge the hydraulic oil. As a result, the output shafts 35L and 35R of the traveling motors 36L and 36R rotate forward (forward rotation) at a speed proportional to the amount of swing of the traveling operating member 54, and the work machine 1 moves straight forward.

Further, when the traveling operation member 54 is swung rearward (in the direction of arrow A2 in FIG. 5), the operating valve 55b is operated and the pilot pressure is set by the operating valve 55b, and the pressure receiving portions 52b of the traveling pumps 52L and 52R are set. The pilot pressure set in is acted on, and the swash plate of the traveling pumps 52L and 52R is tilted from the neutral position to the reverse side, so that the traveling pumps 52L and 52R discharge the hydraulic oil. As a result, the output shafts 35L and 35R of the traveling motors 36L and 36R reverse (reverse rotation) at a speed proportional to the swing amount of the traveling operating member 54, and the work machine 1 moves straight backward.

Further, when the traveling operation member 54 is swung to the right (in the direction of arrow A3 in FIG. 5), the operating valve 55c is operated and the pilot pressure is set by the operating valve 55c, and the pressure receiving portion 52a of the traveling pump 52L and the pressure receiving portion 52a The pilot pressure set on the pressure receiving portion 52b of the traveling pump 52R acts to tilt the swash plate of the traveling pump 52L to the forward rotation side and the traveling pump 52R to the reverse rotation side. As a result, the output shaft 35L of the left traveling motor 36L rotates forward and the output shaft 35R of the right traveling motor 36R reverses, and the work machine 1 turns to the right (super-credit turning). When the traveling operation member 54 is swung to the left (in the direction of arrow A4 in FIG. 5), the operation valve 55d is operated and the pilot pressure is set by the operation valve 55d, and the pressure receiving portion 52b of the traveling pump 52L and the traveling pump The pilot pressure set on the pressure receiving portion 52a of the 52R acts to tilt the swash plate of the traveling pump 52L to the reverse rotation side and the traveling pump 52R to the forward rotation side. As a result, the output shaft 35L of the left traveling motor 36L reverses, the output shaft 35R of the right traveling motor 36R rotates forward, and the work machine 1 turns to the left (super-credit turning).

Further, when the traveling operation member 54 is swung in the oblique direction, the output shaft 35L of the traveling motor 36L on the left side and the traveling motor 36R on the right side due to the differential pressure of the pilot pressure acting on the pressure receiving portion 52a and the pressure receiving portion 52b, The rotation direction and rotation speed of the 35R are determined, and the work machine 1 makes a right turn (right turn) or a left turn (left turn) while moving forward or backward.
By the way, the working machine 1 may include an anti-stall control valve 48. The anti-stall control valve 48 is provided in an oil passage (discharge oil passage 40) between a plurality of operating valves 55 (55a, 55b, 55c, 55d) and the sub pump P1. The anti-stall control valve 48 is an electromagnetic proportional valve whose opening degree can be changed. The anti-stall control valve 48 acts on a plurality of operating valves 55 (55a, 55b, 55c, 55d) based on a decrease (drop amount) ΔE1 of the engine speed (engine speed E1) of the engine 60. Primary pilot pressure) can be set. The engine speed can be detected by the detection sensor 91 of the engine speed E1. The engine speed E1 detected by the detection sensor 91 is input to the work control device 70.

FIG. 7 shows the relationship between the engine speed, the running primary pressure (primary pilot pressure), and the setting lines L51 and L52. The setting line L51 shows the relationship between the engine speed E1 and the primary running pressure when the reduction amount ΔE1 is less than a predetermined value (less than the anti-stall determination value). The setting line L52 shows the relationship between the engine speed E1 and the primary running pressure when the reduction amount ΔE1 is equal to or greater than the anti-stall determination value.

When the reduction amount ΔE1 is less than the anti-stall determination value, the work control device 70 anti-stalls so that the relationship between the engine speed E1 and the primary running pressure matches the reference pilot pressure indicated by the setting line L51. The opening degree of the control valve 48 is adjusted. Further, when the decrease amount ΔE1 is equal to or greater than the anti-stall determination value, the work control device 70 anti-storms so that the relationship between the engine speed E1 and the primary running pressure coincides with the setting line L52 lower than the reference pilot pressure. The opening degree of the stall control valve 48 is adjusted. On the setting line L52, the traveling primary pressure with respect to the predetermined engine speed E1 is lower than the traveling primary pressure on the setting line L51. That is, when focusing on the same engine speed E1, the running primary pressure of the setting line L52 is set lower than the running primary pressure of the setting line L51. Therefore, the pressure (pilot pressure) of the hydraulic oil entering the operation valve 55 can be suppressed low by the control based on the setting line L52. As a result, the swash plate angles of the traveling pumps 52L and 52R are adjusted, the load acting on the engine is reduced, and the engine stall can be prevented. Although one setting line L52 is shown in FIG. 7, there may be a plurality of setting lines L52. For example, the setting line L52 may be set for each engine speed E1. Further, it is preferable that the work control device 70 has data indicating the setting line L51 and the setting line L52, control parameters such as functions, and the like.

As shown in FIG. 6, the work system hydraulic system is a system that operates the work device 3 and the like. The work system hydraulic system is a system that operates the work device 3 by the flood control when the hydraulic drive device 64 is driven. The work system hydraulic system includes a plurality of control valves 51 and a main pump P2 which is a hydraulic pump for discharging hydraulic oil. The main pump P2 is a pump arranged at a position different from that of the sub pump P1 and is composed of a low-capacity gear pump. The main pump P2 can discharge the hydraulic oil stored in the hydraulic oil tank. In particular, the main pump P2 mainly discharges hydraulic oil that operates the hydraulic actuator.

An oil passage 51f is provided on the discharge side of the main pump P2. A plurality of control valves 51 are connected to the oil passage 51f. The plurality of control valves 51 include a boom control valve 51a, a bucket control valve 51b, and a preliminary control valve 51c. The boom control valve 51a is a valve that controls the boom cylinder 14, the bucket control valve 51b is a valve that controls the work tool cylinder 15, and the spare control valve 51c is a valve that controls the hydraulic actuator of the spare attachment. Is.

The boom 10 and the work tool 11 can be operated by the work operation member 37 included in the operation device 43. The work operation member 37 is an operation member that is supported by a plurality of operation valves 59 and swings in the left-right direction (body width direction) or the front-rear direction. By tilting the work operation member 37, the operation valve 59 provided at the lower part of the work operation member 37 can be operated.
The plurality of operating valves 59 and the plurality of control valves 51 are connected to each other by a plurality of working oil passages 47 (47a, 47b, 47c, 47d). Specifically, the operation valve 59a is connected to the boom control valve 51a via the working oil passage 47a. The operation valve 59b is connected to the boom control valve 51a via a working oil passage 47b. The operation valve 59c is connected to the bucket control valve 51b via the work oil passage 47c. The operation valve 59d is connected to the bucket control valve 51b via the work oil passage 47d. Each of the plurality of operation valves 59a to 59d can set the pressure of the hydraulic oil to be output according to the operation of the work operation member 37.

When the work operation member 37 is tilted forward, the operation valve 59a is operated and the pilot pressure is output from the operation valve 59a. This pilot pressure acts on the pressure receiving portion of the boom control valve 51a, and supplies the hydraulic oil containing the boom control valve 51a to the rod side of the boom cylinder 14, so that the boom 10 descends.
When the work operation member 37 is tilted to the rear side, the operation valve 59b is operated and the pilot pressure is output from the operation valve 59b. This pilot pressure acts on the pressure receiving portion of the boom control valve 51a, and the hydraulic oil that has entered the boom control valve 51a is supplied to the bottom side of the boom cylinder 14, so that the boom 10 rises.

That is, the boom control valve 51a is attached to the boom cylinder 14 in response to the hydraulic oil pressure set by the operation of the work operation member 37 (the pilot pressure set by the operation valve 59a and the pilot pressure set by the operation valve 59b). The flow rate of the flowing hydraulic oil can be controlled.
When the work operation member 37 is tilted to the right, the operation valve 59c is operated and the pilot pressure acts on the pressure receiving portion of the bucket control valve 51b. As a result, the bucket control valve 51b operates in the direction of extending the work tool cylinder 15, and the work tool 11 dumps at a speed proportional to the amount of tilt of the work operation member 37.

When the work operation member 37 is tilted to the left, the operation valve 59d is operated and the pilot oil acts on the pressure receiving portion of the bucket control valve 51b. As a result, the bucket control valve 51b operates in the direction of reducing the work tool cylinder 15, and the work tool 11 squeezes at a speed proportional to the amount of tilt of the work operation member 37.
That is, the bucket control valve 51b is a work tool cylinder according to the hydraulic oil pressure set by the operation of the work operation member 37 (the pilot pressure set by the operation valve 59c and the pilot pressure set by the operation valve 59d). The flow rate of hydraulic oil flowing through 15 can be controlled. That is, the operation valves 59a, 59b, 59c, 59d change the pressure of the hydraulic oil according to the operation of the work operation member 37, and the changed hydraulic oil is used as the boom control valve 51a, the bucket control valve 51b, and the preliminary control valve. It is supplied to a control valve such as 51c.

The operation of the spare attachment can be performed by a switch 56 provided around the driver's seat 7 (see FIG. 8). The switch 56 is composed of, for example, a swingable seesaw type switch, a slidable slide type switch, or a pushable push type switch. The operation of the switch 56 is input to the work control device 70. The first solenoid valve 56a and the second solenoid valve 56b, which are composed of solenoid valves and the like, open according to the amount of operation of the switch 56. As a result, the pilot oil is supplied to the preliminary control valve 51c connected to the first solenoid valve 56a and the second solenoid valve 56b, and the spare actuator of the spare attachment is operated by the hydraulic oil supplied from the preliminary control valve 51c.

In the above-described embodiment, the boom 10 is raised and lowered by swinging one work operation member 37 to the front side or the rear side, and the work tool 11 such as a bucket is operated by swinging to the left or right side. However, instead of this, at least a pair of work operation members 37 are provided, and the boom 10 is moved up and down by swinging one work operation member 37, and the work is performed by swinging the other work operation member 37. It may be configured to operate the tool 11. In this case, the operation valves 59a and 59b set the pilot pressure of one work operation member 37 according to the swing, and the operation valves 59c and 59d set the pilot pressure of the other work operation member 37 according to the swing. .. That is, the boom 10 and the work tool 11 may be capable of combined operation.

The amount of operation of the operation member (work operation member 37, traveling operation member 54) can be detected by the operation detection device 77. The operation detection device 77 is connected to a work control device 70 described later. The operation detection device 77 includes a first operation detection device 77A and a second operation detection device 77B. The first operation detection device 77A detects the operation amount (work operation amount) of the work operation member 37. The second operation detection device 77B detects the operation amount (travel operation amount) of the travel operation member 54. The first operation detection device 77A and the second operation detection device 77B are position sensors and the like that detect the position of the operation member.

FIG. 8 shows a control block diagram of the working machine 1. As shown in FIG. 8, the power control device 67 and the work control device 70 are connected to each other. The power control device 67 includes an inverter 67A and an inverter control unit 67B. The inverter 67A has, for example, a plurality of switching elements, and converts direct current into alternating current by switching the switching elements or the like. The inverter 67A is connected to the motor generator 63 and the battery 66. The inverter control unit 67B is composed of a CPU, an electric / electronic circuit, and the like, and outputs a predetermined signal to the inverter control unit 67B to operate the motor generator 63 as a motor or as a generator. The amount of electricity stored (remaining amount) in the battery 66 can be detected by the charge detection sensor 97 provided in the battery 66.

The work control device 70 is a device that controls various work machines, and is composed of a CPU, an electric / electronic circuit, and the like. The work control device 70 performs control (hydraulic control) related to hydraulic pressure (hydraulic oil). In the flood control, the work control device 70 excites and degausses the solenoids of the speed change switching valve 44, the first solenoid valve 56a, and the second solenoid valve 56b, as described above. The work control device 70 also operates as a controller for controlling the power control device 67. The work control device 70 outputs an assist command to the inverter control unit 67B, and the inverter control unit 67B operates the motor generator 63 as a motor. The work control device 70 outputs a power generation command to the inverter control unit 67B, and the inverter control unit 67B operates the motor generator 63 as a generator. That is, under the control of the work control device 70, the motor generator 63 can perform an assist operation for assisting the driving of the engine 60 and a power generation operation for operating as a generator by the power of the engine 60 to generate electricity. The work control device 70 sets and commands the power running torque when the motor generator 63 assists the operation and the regenerative torque when the power generation operation is performed to the power control device 67.

When the motor generator 63 performs the assist operation, the power of the engine 60 and the motor generator 63 is transmitted to the hydraulic drive device 64. When the motor generator 63 performs the power generation operation, the power of the engine 60 is transmitted to the hydraulic drive device 64, and the power generated by the motor generator 63 is charged to the battery 66. The motor generator 63 is driven by the electric power charged in the battery 66.

In the above-described embodiment, the work control device 70 and the power control device 67 are separately configured, but may be integrally configured, and the present invention is not limited to the above-described embodiment.
The work control device 70 includes a storage unit 70a, a power running torque setting unit 70b, a regenerative torque setting unit 70c, and an operation control unit 70d. The storage unit 70a is composed of a non-volatile memory or the like. The power running torque setting unit 70b, the regenerative torque setting unit 70c, and the operation control unit 70d are composed of an electric / electronic circuit provided in the work control device 70, a program stored in a CPU, or the like. The storage unit 70a, the power running torque setting unit 70b, the regenerative torque setting unit 70c, and the operation control unit 70d may be provided in the power control device 67.

The storage unit 70a stores control information when the motor generator 63 performs either an assist operation or a charging operation, for example, a control map as shown in FIG. The control map shows the relationship between the engine speed (engine speed E1) and the switching between the assist operation and the charging operation (operation switching), the relationship between the engine speed E1 and the power running torque during the assist operation, and the engine rotation. The relationship between the number E1 and the regenerative torque in the case of charging operation is shown. In the above-described embodiment, the control information is a control map, but the relationship between the engine speed E1 and the operation switching, the relationship between the engine speed E1 and the regenerative torque in the case of assist operation, and the engine speed. The relationship between E1 and the regenerative torque in the case of charging operation may be shown by a control table, parameters, functions, etc., and is not limited.

The power running torque setting unit 70b sets the power running torque when performing the assist operation. As shown in FIG. 9, the power running torque setting unit 70b refers to control information such as a control map stored in the storage unit 70a, and sets the power running torque with respect to the engine speed E1 using, for example, the standard line L1. To do.
The regenerative torque setting unit 70c sets the regenerative torque when performing the power generation operation. As shown in FIG. 9, the regenerative torque setting unit 70c refers to the control information in the same manner as the power running torque setting unit 70b, and sets the regenerative torque with respect to the engine speed E1 using, for example, the standard line L1. The standard line L1 includes an inclined line L1a in which the torque changes according to the engine speed E1 and a constant line L1b in which the torque is constant regardless of the engine speed E1.

The operation control unit 70d executes an assist operation by outputting the power running torque set by the power running torque setting unit 70b to the power control device 67 when the engine speed is equal to or less than the first rotation speed N1. When the rotation speed is the second rotation speed N2 or more, which is larger than the first rotation speed, the regenerative torque set by the regenerative torque setting unit 70c is output to the power control device 67 to execute the power generation operation.

By the way, in the work machine 1, when the work operation member 37 is operated, the first rotation speed N1 and the second rotation speed N2 indicating switching between the assist operation and the power generation operation can be changed. FIG. 10A shows the work operation amounts BD and BU detected by the first operation detection device 77A when the work operation member 37 is operated to either the front side or the rear side (when the boom cylinder 14 is expanded and contracted). The work operation amount BD indicates the operation amount when the boom cylinder 14 is contracted, that is, the boom 10 is lowered, and the work operation amount BU is the operation amount when the boom cylinder 14 is extended, that is, the boom 10 is raised. It shows.

Further, FIG. 10B shows the work operation amounts SU and SD detected by the second operation detection device 77B when the work operation member 37 is operated to either the left side or the right side (when the work tool cylinder 15 is expanded and contracted). There is. The work operation amount SU indicates the operation amount when the work tool cylinder 15 is contracted, that is, the tip of the work tool 11 is raised, and the work operation amount SD indicates the operation amount when the work tool cylinder 15 is extended, that is, the tip of the work tool 11. Shows the amount of operation when lowering. The work operation amount BD, BU, SU, and SD all gradually increase the work operation member 37 from the neutral position according to the tilt.

As shown in FIG. 8, the work control device 70 has a switching change unit 70h. The switching change unit 70h is composed of an electric / electronic circuit provided in the work control device 70, a program stored in a CPU, and the like. The switching change unit 70h may be provided in the power control device 67.
The switching change unit 70h changes the first rotation speed N1 and the second rotation speed N2 based on the work operation amounts BD, BU, SU, and SD of the work operation member 37.

As shown in FIG. 11A, the switching change unit 70h has switching information (first switching lines L31, L32) indicating the relationship between the work operation amounts SU and SD and the first rotation speed N1 and the second rotation speed N2. doing. When the work operation member 37 is operated, the switching change unit 70h changes the first rotation speed N1 and the second rotation speed N2 to the values indicated by the first switching lines L31 and L32. The first switching line L31 is a line for setting the first rotation speed N1, and the second switching line L32 is a line for setting the second rotation speed N2.

As shown in the first switching lines L31 and L32 of FIG. 11A, when the work operation member 37 is not operated and the work operation member 37 is in the neutral position, the switching change unit 70h has the first rotation speed N1 and the second rotation speed N2. Each of the above is set to the reference engine speed E1. As shown in the first switching lines L31 and L32, when the work operation member 37 is operated, the first rotation speed N1 and the second rotation speed N2 are gradually increased according to the work operation amount SU and SD. Further, as shown in the first switching lines L31 and L32, the switching change unit 70h sets the first rotation speed N1 and the second rotation speed N2 to fixed values when the work operation amounts SU and SD exceed the predetermined values W20. To.

As shown in FIG. 11B, the switching change unit 70h has switching information (second switching lines L33, L34) indicating the relationship between the work operation amounts BD and BU and the first rotation speed N1 and the second rotation speed N2. doing. When the work operation member 37 is operated, the switching change unit 70h changes the first rotation speed N1 and the second rotation speed N2 to the values indicated by the second switching lines L33 and L34. The second switching line L33 is a line for setting the first rotation speed N1, and the second switching line L34 is a line for setting the second rotation speed N2.

As shown in the second switching lines L33 and L34 of FIG. 11B, when the work operation member 37 is not operated and the work operation member 37 is in the neutral position, the switching change unit 70h has the first rotation speed N1 and the second rotation speed N2. Each of the above is set to the reference engine speed E1. As shown in the second switching lines L33 and L34, when the work operation member 37 is operated, the first rotation speed N1 and the second rotation speed N2 are gradually increased according to the work operation amount BD and BU. Further, as shown in the second switching lines L33 and L34, the switching change unit 70h sets the first rotation speed N1 and the second rotation speed N2 to fixed values when the work operation amount BD and BU exceed the predetermined values W21. To.

In the above-described embodiment, the first rotation speed N1 and the second rotation speed N2 are increased according to the work operation amount BU even when the boom cylinder 14 is extended (when the boom 10 is raised). As shown in the line L20 of FIG. 11B, when the operation of raising the boom 10 is performed, each of the first rotation speed N1 and the second rotation speed N2 is fixed to the reference value and changed according to the work operation amount BU. Instead, when the boom 10 is lowered, the first rotation speed N1 and the second rotation speed N2 may be increased according to the work operation amount BD.

Further, when a plurality of work operation members 37 are provided and the operation of the boom 10 and the operation of the work tool 11 can be performed separately, the switching change unit 70h is set to the first rotation speed N1 during the combined operation. , The second rotation speed N2 is fixed to the reference value and is not changed.
FIG. 12 shows the operation of changing the first rotation speed N1 and the second rotation speed N2 when the operating member is operated.

As shown in FIG. 12A, the switching change unit 70h refers to the work operation amounts BD, BU, SU, and SD (S70). The switching change unit 70h determines whether or not it is a combined operation (S71). For example, when the operation amount of both the work operation amount SU, SD and the work operation amount BD, BU is not zero, or the operation amount of both the work operation amount SU, SD and the work operation amount BD, BU is predetermined. If it is larger than the operation amount of, the switching change unit 70h determines that it is a combined operation (S71, Yes). In the case of the combined operation, the switching change unit 70h holds the first rotation speed N1 and the second rotation speed N2 at the reference values (S72). The switching change unit 70h determines whether or not the boom 10 is rising (S73). When the switching change unit 70h determines that the work operation amount BU is equal to or higher than a predetermined value and the boom 10 is rising (S73, Yes), the switching change unit 70h holds the first rotation speed N1 and the second rotation speed N2 as reference values (S73, Yes). S74). When the boom 10 is not raised (S73, No), the switching change unit 70h changes the first rotation speed N1 and the second rotation speed N2 according to the work operation amounts BD, SU, and SD (S75). When the work operation amounts BD, BU, SU, and SD are zero, the switching change unit 70h holds the first rotation speed N1 and the second rotation speed N2 as reference values.

In FIG. 12A, when the boom 10 rises, the first rotation speed N1 and the second rotation speed N2 are not changed with the reference values, but instead of this, the work is performed regardless of the operation of the boom 10. The first rotation speed N1 and the second rotation speed N2 may be changed according to the operation amounts BD, BU, SU, and SD.
Further, when the remaining amount of the battery 66 is smaller than the predetermined remaining amount in the switching changing unit 70h, the switching changing unit 70h has any value of the work operation amount BD, BU, SU, SD. That is, even if the work operation member 37 is operated, the first rotation speed N1 and the second rotation speed N2 may be held at the reference values.

Further, in the above-described embodiment, both the first rotation speed N1 and the second rotation speed N2 are changed based on the work operation amounts BD, BU, SU, and SD, but the first rotation speed N1 and the second rotation speed N1 and the second rotation speed are changed. Either one of the rotation speeds N2 may be changed.
Further, the inclination of the first switching lines L31 and L32 and the second switching lines L33 and L34, that is, the amount of increase in the first rotation speed N1 and the second rotation speed N2 with respect to the work operation amounts BD, BU, SU and SD is a slide. Setting such as a switch, a volume switch, etc. It may be set according to the operation amount of the operation tool.

In the above-described embodiment, the switching change unit 70h fixes the first rotation speed N1 and the second rotation speed N2 to the reference values in the combined operation in which the operation of the boom 10 and the operation of the work tool 11 are operated separately. However, the first rotation speed N1 and the second rotation speed N2 may be fixed to the reference values at the time of the combined operation in which the working system and the traveling system are operated at the same time. That is, based on the work operation amounts BD, BU, SU, SD when the work operation member 37 is operated and the travel operation amounts ST1 and ST2 when the travel operation member 54 is operated, the first rotation speed N1, the first 2 The number of revolutions N2 may be set. The traveling operation amounts ST1 and ST2 are operation amounts when turning (super-credit turning, trusting ground turning), as will be described later.

As shown in FIG. 12B, the switching change unit 70h refers to the work operation amounts BD, BU, SU, SD and the travel operation amounts ST1 and ST2 (S100). The switching change unit 70h determines whether or not it is a combined operation (S101). For example, when both the work operation amounts BD, BU, SU, SD and the travel operation amounts ST1 and ST2 are not zero, the switching change unit 70h determines that the operation is a combined operation (S101, Yes). In the case of the combined operation, the switching change unit 70h holds the first rotation speed N1 and the second rotation speed N2 at the reference values (S102). In particular, when the work operation amount BD is not zero, the boom 10 is raised, and the machine body 2 is turning larger than any of the traveling operation amounts ST1 and ST2 to zero, the switching change unit 70h has the first rotation speed. N1 and the second rotation speed N2 are held at the reference values.

When the switching changing unit 70h is not a combined operation (S101, No), the switching changing unit 70h changes the first rotation speed N1 and the second rotation speed N2 according to the work operation amount BD, BU, SU, and SD. (S103).
The work machine 1 includes a machine body 2, an engine 60, a motor generator 63, a work device 3, a work operation member 37 for operating the work device 3, and an engine speed E1 of the first speed N1 or less. In this case, the operation control unit 70d that performs the assist operation and the power generation operation when the engine speed E1 is larger than the first speed N1 and the second speed N2 or more, and the work operation amount BD of the work operation member 37, It is provided with a switching change unit 70h for changing either the first rotation speed N1 or the second rotation speed N2 based on the BU, SU, and SD. According to this, the timing (switching position) of the start of the assist operation and the power generation operation with respect to the engine speed E1 is set according to the operation amount BD, BU, SU, SD of the work operation member 37 when the work device 3 is operated. Since it can be changed, the output can be flexibly changed according to the work.

The work device 3 swings the boom 10 provided on the machine body 2 swingably, the boom cylinder 14 swinging the boom 10, the work tool 11 swingably provided on the boom 10, and the work tool 11. It has a work tool cylinder 15 to be moved, and the switching change unit 70h has a first rotation speed N1 and a second rotation according to the work operation amount SU and SD when the work tool cylinder 15 is operated by the work operation member 37. Change any of the numbers N2. According to this, when the work is performed by the work tool 11 such as a bucket, the combined output of the engine 60 and the motor / generator 63 can be changed according to the operation.

When the boom cylinder 14 and the work tool cylinder 15 are operated by the work operation member 37, the switching change unit 70h sets the first rotation speed N1 and the second rotation speed N2 according to the work operation amounts BD, BU, SU, and SD. Not going to change. According to this, when the load is high, such as when the boom 10 and the work tool 11 are working at the same time, the first rotation speed N1 and the second rotation speed N2 in the assist operation and the power generation operation should not be changed. Therefore, the work operation member 37 can perform the operation while maintaining the balance between the assist operation and the power generation operation.

When the boom cylinder 14 is operated to the ascending side of the boom 10 by the work operation member 37, the switching change unit 70h does not change the first rotation speed N1 and the second rotation speed N2 according to the work operation amount BU. According to this, in the case of a high load such as when the boom 10 rises, the assist operation and the power generation are performed by not changing the first rotation speed N1 and the second rotation speed N2 in the assist operation and the power generation operation. The operation can be performed by the work operation member 37 while maintaining a balance with the operation.

In the above-described embodiment, either the first rotation speed N1 or the second rotation speed N2 is changed based on the work operation amount BD, BU, SU, SD of the work operation member 37, but the traveling operation member 54 Either the first rotation speed N1 or the second rotation speed N2 may be changed based on the operation amount (running operation amount).
As shown in FIG. 8, the work control device 70 has a switching change unit 170h. The switching change unit 170h is composed of an electric / electronic circuit provided in the work control device 70, a program stored in a CPU or the like, and the like. The switching change unit 170h may be provided in the power control device 67.

As shown in FIG. 13, the switching change unit 170h has switching information (third switching line L35, which indicates the relationship between the traveling operation amount (first operation amount) ST1 and the first rotation speed N1 and the second rotation speed N2. It has L36). The traveling operation amount ST1 is the traveling operation amount of the traveling operation member 54 when the traveling operating member 54 is swung to either the left side (left side) or the right side (right side) to make a turning. That is, the third switching line L35 is a line for setting the first rotation speed N1 according to the traveling operation amount ST1 when the turning is performed, and the third switching line L36 is the line when the turning is performed. This is a line for setting the second rotation speed N2 according to the traveling operation amount ST1 of.

Further, the switching change unit 170h has switching information (fourth switching lines L37 and L38) indicating the relationship between the traveling operation amount (second operation amount) ST2 and the first rotation speed N1 and the second rotation speed N2. ing. The traveling operation amount ST2 is the traveling operation amount of the traveling operation member 54 when the traveling operating member 54 is swung to either the left side (left side) or the right side (right side) to perform a super-credit turning. That is, the fourth switching line L37 is a line that sets the first rotation speed N1 according to the traveling operation amount ST2 when the super-credit turn is performed, and the fourth switching line L38 performs the super-credit turn. This is a line for setting the second rotation speed N2 according to the traveling operation amount ST2 at the time.

As shown in the third switching lines L35 and L36 of FIG. 13, in the switching changing unit 170h, when the work operation member 37 is not operated and is in the neutral position, the first rotation speed N1 and the second rotation speed N2 Each of the above is set to the reference engine speed E1. As shown in the third switching lines L35 and L36, when the work operation member 37 is operated, the first rotation speed N1 and the second rotation speed N2 are gradually increased according to the traveling operation amount ST1.

Further, as shown in the fourth switching lines L37 and L38 of FIG. 13, when the work operation member 37 is not operated and the work operation member 37 is in the neutral position, the switching change unit 170h has the first rotation speed N1 and the second rotation. Each of the numbers N2 is set to the reference engine speed E1. As shown in the fourth switching lines L37 and L38, when the work operation member 37 is operated, the first rotation speed N1 and the second rotation speed N2 are gradually reduced according to the traveling operation amount ST2.

That is, when the switching change unit 170h is operated to turn the traveling operation member 54 in the ground, the traveling operation member 54 is turned in the super-credit while increasing the first rotation speed N1 and the second rotation speed N2. When operated to do so, the first rotation speed N1 and the second rotation speed N2 are reduced.
FIG. 14 shows the operation of changing the first rotation speed N1 and the second rotation speed N2 when the operating member is operated.

As shown in FIG. 14, the switching changing unit 170h determines whether or not the traveling operation member 54 has been operated (S80), and when the traveling operating member 54 is operated (S80, Yes), it is a turning point. It is determined whether it is a super-credit turn (S81). For example, the switching change unit 170h is the pilot pressure (first pressure) of each of the traveling oil passages 45 (first traveling oil passage 45a, second traveling oil passage 45b, third traveling oil passage 45c, fourth traveling oil passage 45d). , 2nd pressure, 3rd pressure, 4th pressure) The pressure of the pressure detection sensor 171 for detecting) is referred to. The first pressure is the pilot pressure acting on the first running oil passage 45a, the second pressure is the pilot pressure acting on the second running oil passage 45b, and the third pressure is the pilot pressure acting on the third running oil passage 45c. The fourth pressure is a pilot pressure acting on the fourth traveling oil passage 45d. Here, in the pressure detection sensor 171, the pressures of the first pressure, the second pressure, the third pressure, and the fourth pressure are larger than zero, and the first pressure and the second pressure are substantially the same pressure. When either the third pressure or the fourth pressure is equal to or higher than a predetermined value, the switching change unit 170h determines that the turning is true. Alternatively, the pressure detection sensor 171 has the pressures of the first pressure, the second pressure, the third pressure, and the fourth pressure larger than zero, of which the third pressure and the fourth pressure are substantially the same pressure and the third pressure. When the pressures of the 1st pressure and the 2nd pressure are equal to or higher than a predetermined value, the switching change unit 170h determines that the turning is true. On the other hand, in the switching change unit 170h, the pressure detection sensor 171 has a pressure of any of the first pressure and the second pressure among the first pressure, the second pressure, the third pressure, and the fourth pressure being zero and the third pressure. If either the pressure or the fourth pressure is zero, it is judged to be a super-credit turn. In other words, when the first pressure and the fourth pressure are equal to or higher than the predetermined pressure and the pressures of the second pressure and the third pressure are substantially zero, the switching change unit 170h has the second pressure and the third pressure equal to or higher than the predetermined pressure. When the pressure is high and the pressures of the first pressure and the fourth pressure are substantially zero, it is judged that the rotation is super-credit.

In the above-described embodiment, it is determined whether the rotation is a credible turn or a super credible turn based on the first pressure to the fourth pressure detected by the pressure detection sensor 171. Not limited.
When the switching change unit 170h determines that the rotation is a turning point (S81, Yes), the traveling operation amount detected by the second operation detecting device 77B is set as the traveling operation amount ST1, and the traveling operation amount ST1 is changed to the third switching. It is applied to the lines L35 and L36 to increase the first rotation speed N1 and the second rotation speed N2 (S82). On the other hand, when the switching change unit 170h determines that the rotation is super-credit turning (S81, No), the traveling operation amount detected by the second operation detecting device 77B is set as the traveling operation amount ST2, and the traveling operation amount ST2 is set. It is applied to the fourth switching lines L37 and L38 to reduce the first rotation speed N1 and the second rotation speed N2 (S83). The switching change unit 170h holds the first rotation speed N1 and the second rotation speed N2 as a reference when neither the turning of the ground nor the turning of the super-credit is performed. Further, the switching change unit 170h holds the first rotation speed N1 and the second rotation speed N2 as a reference even when the traveling operation member 54 is not operated (S84).

When the remaining amount of the battery 66 is smaller than the predetermined remaining amount in the switching changing unit 170h, the switching changing unit 170h has the switching operation amount ST1 and ST2 regardless of the value, that is, that is, Even if the traveling operation member 54 is operated, the first rotation speed N1 and the second rotation speed N2 may be held at the reference values.
Further, in the above-described embodiment, both the first rotation speed N1 and the second rotation speed N2 are changed based on the traveling operation amounts ST1 and ST2, but the first rotation speed N1 and the second rotation speed N2 Either one may be changed.

The work machine 1 includes a switching change unit 170h that changes either the first rotation speed N1 or the second rotation speed N2 based on the operation amount of the travel operation member 54 (travel operation amount ST1, ST2). According to this, the timing (switching position) of the start of the assist operation and the power generation operation with respect to the engine speed E1 can be changed according to the travel operation amounts ST1 and ST2 when the work machine 1 is traveled. The output can be changed flexibly according to.

In the airframe 2, of the pair of traveling devices 4L and 4R, one of the pair of traveling devices 4L and 4R is driven and the other is stopped and turned in the first turning (credit turning), and the pair of traveling devices 4L and 4R are driven in opposite directions. A second turn (super-credit turn) that turns is possible, and the switching change unit 170h has a traveling operation amount (first operation amount) ST1 and a second turn when performing the first turn (credit turn). Either the first rotation speed N1 or the second rotation speed N2 is changed according to each of the traveling operation amount (second operation amount) ST2 when performing (super-credit turning). According to this, when the working machine 1 makes a turning point and a super turning point, the output can be changed according to the traveling operation amounts ST1 and ST2.

When performing the first turn (credit turn), the switching change unit 170h increases either the first rotation speed N1 or the second rotation speed N2 according to the traveling operation amount (first operation amount) ST1. When two turns (super-credit turn) are performed, either the first rotation speed N1 or the second rotation speed N2 is reduced according to the traveling operation amount (second operation amount) ST2. According to this, when a load such as super-credit turning is applied, either the first rotation speed N1 or the second rotation speed N2 is reduced so that the operation on the power generation operation side is likely to occur. , When the load such as turning is small, either the first rotation speed N1 or the second rotation speed N2 is increased so that the operation on the assist operation side is likely to occur. As a result, useless assist can be reduced.

The work machine 1 includes a pair of traveling motors 36L and 36R for driving the pair of traveling devices 4L and 4R, and a pair of traveling pumps 52L and 52R for driving the pair of traveling motors 36L and 36R. The member 54 operates a pair of traveling pumps 52L and 52R.
Of the pair of traveling pumps 52L and 52R, the traveling pump 52L is a swash plate type that changes the driving force for driving one of the traveling motors 36R according to the pilot pressure acting on the first pressure receiving portion and the second pressure receiving portion. Of the pair of traveling pumps 52L and 52R, the traveling pump 52R changes the driving force for driving the other traveling motor 36R according to the pilot pressure acting on the third pressure receiving portion and the fourth pressure receiving portion. It is a swash plate type pump. According to this, when the work machine 1 is driven by the traveling motors 36L, 36R and the traveling pumps 52L, 52R, the first rotation speed N1 and the second rotation speed N2 are set according to the traveling operation amounts ST1 and ST2. By changing it, more stable running can be performed. In particular, it is possible to improve the feeling of operation when the traveling operation member 54 is operated.

By the way, the work control device 70 may set the timing of the assist operation based on the transition of the engine speed E1 after the operation of the operation members (work operation member 37, travel operation member 54). The power control device 67 may set the timing of the assist operation based on the transition of the engine speed E1 after the operation of the operation members (work operation member 37, travel operation member 54).

FIG. 15 is a diagram showing the relationship between the transition M10 of the engine speed E1 and the turning speed V10. As shown in FIG. 15, when the traveling operation member 54 is operated in the direction of turning or super-turning at the time point P30, the traveling pumps 52L and 52R go through the neutral position and then move in the forward or reverse direction. Due to the effect of switching, the transition M10 of the engine speed E1 once rises from the time point P30 and gradually falls from the time point P31 after the predetermined time T25. The operation control unit 70d of the work control device 70 does not perform the assist operation between the time point P30 and the time point P31, but performs the assist operation after the engine speed E1 drops at the time point P31 or higher. That is, the operation control unit 70d of the work control device 70 assists when the turning speed V10 when the body 2 is turned by the pair of traveling devices 4L and 4R increases and the engine speed E1 increases and then decreases. Start operation. The work machine 1 is provided with a rotation detection device 85 that detects the rotation speeds of the traveling devices 4L and 4R (see FIG. 8). The rotation detection device 85 is a sensor that detects the rotation speeds M1 and M2 of the output shafts 35L and 35R of the traveling motors 36L and 36R, respectively. The work control device 70 can calculate the turning speed V10 based on the rotation speeds M1 and M2 detected by the rotation detection device 85.

FIG. 16 shows the flow of setting the timing of the assist operation in the operation control unit 70d of the work control device 70. In the description of FIG. 16, when the assist operation is performed, the power running torque is set by the power running torque setting unit 70b based on the engine speed E1 as described above.
As shown in FIG. 16, the motion control unit 70d determines whether or not the traveling operation member 54 has been operated (S91), and when the traveling operation member 54 is operated (S91, Yes), the turning operation (trust) It is determined whether or not the operation is a turning operation or a super-credit turning operation (S92). As described above, the first pressure, the second pressure, and the third pressure detected by the pressure detection sensor 171 are used to determine whether or not the rotation operation (the operation of turning the ground or the operation of the super-credit turning). , Based on the 4th pressure.

The operation control unit 70d monitors the transition M10 of the engine speed E1 in the case of a turning operation (operation of turning on the ground, operation of turning on the ground) (S92, Yes) (S93). The operation control unit 70d determines whether or not the engine speed E1 has changed from an upward trend to a downward trend (S94). When the engine speed E1 does not change from the upward trend to the downward trend (S94, No), the assist operation is not performed, that is, the operation control unit 70d does not start the assist operation. When the engine speed E1 changes from an upward trend to a downward trend (S94, Yes), the motion control unit 70d starts an assist operation (S95). Whether or not the engine speed E1 has changed from an upward trend to a downward trend is determined when the moving average value of the amount of change in the engine speed E1 in a predetermined time (for example, 50 ms) becomes equal to or less than the predetermined engine speed. It may be determined that the number E1 has changed from an upward trend to a downward trend, or the downward transition (damping rate) of the engine speed E1 is obtained by a low-pass filter, and when the damping rate is equal to or higher than the determination value, the engine speed It may be determined that E1 has changed from an upward trend to a downward trend.

The motion control unit 70d may start the assist operation when the turning speed V10 is equal to or higher than a predetermined value and the engine speed E1 changes from an upward trend to a downward trend.
The work machine 1 includes a control device (work control device 70, power control device 67) that sets the timing of the assist operation based on the transition M10 of the engine speed E1 after the operation of the travel operation member 54. According to this, for example, it can be determined from the transition M10 of the engine 60 whether or not the engine 60 needs assistance, assist is performed when assist is required, and assist is not performed when assist is not required. It is possible to improve the efficiency of assist.

When performing the assist operation, the control device (work control device 70, power control device 67) performs the assist operation after the engine speed E1 changes from rising to falling. According to this, when the engine speed E1 tends to increase and there is a surplus capacity, the assist can be performed at the timing when the engine speed E1 starts to decrease without performing the assist.
The work machine 1 includes an operation valve 55 (55a, 55b, 55c, 55d) that sets a pilot pressure according to the operation of the traveling operation member 54, and the hydraulic drive device 64 includes an operation valve 55 (55a, 55b, 55c, The output changes according to the pilot pressure set in 55d). According to this, when the output of the hydraulic drive device 64 is generated by the operation of the operation valve 55 and the engine speed E1 tends to increase or decrease, it is possible to assist more effectively.

The work machine 1 includes a pair of traveling devices 4L and 4R provided on the machine body 2 and a pair of traveling motors 36L and 36R for driving the pair of traveling devices 4L and 4R, and the hydraulic drive device 64 includes a pair of traveling devices 36L and 36R. A pair of traveling pumps 52L and 52R for driving the traveling motors 36L and 36R. According to this, it is possible to effectively assist when the traveling devices 4L and 4R are operated by the traveling motors 36L and 36R and the traveling pumps 52L and 52R.

When the turning speed of the control device (work control device 70, power control device 67) is increased when the machine body 2 is turned by the pair of traveling devices 4L and 4R, and the engine speed E1 is increased and then decreased. Start the assist operation. According to this, when the work machine 1 turns, it is possible to assist more effectively when the engine speed E1 fluctuates.
In the above-described embodiment, the operation valves 55 and 59 are configured to change the pilot pressure when the work operation member 37 and the traveling operation member 57 are operated, but an electric type operation member may be used. That is, the operating devices 43 and 53 may be devices that operate the hydraulic drive devices 64 and the control valves 51 and 48 by electric signals.

In the above-described embodiment, the traveling operation member 54 has been described as an example, but when the work operation member 37 operates a hydraulic pump having a neutral position, the above-described configuration can be applied.
Although the present invention has been described above, it should be considered that the embodiments disclosed this time are exemplary in all respects and are not restrictive. The scope of the present invention is shown by the scope of claims rather than the above description, and is intended to include all modifications within the meaning and scope equivalent to the scope of claims.

1: Working machine 2: Machine body 3: Working device 4L: Traveling device 4R: Traveling device 5: Cabin 7: Driver's seat 10: Boom 11: Working tool 12: Lift link 13: Control link 14: Boom cylinder 15: Working tool cylinder 18: Mounting bracket 20: Right frame part 21: Left frame part 22: Front frame part 23: Bottom frame part 24: Upper frame part 25: Track frame 26: Motor mounting part 31L: First running motor mechanism 31R: Second running Motor mechanism 34: Travel drive mechanism 34L: Drive circuit 34R: Drive circuit 35L: Output shaft 35R: Output shaft 36L: Travel motor 36R: Travel motor 37: Work operation member 38a: Slanted plate switching cylinder 38b: Travel switching valve 39a: No. 1st position 39b: 2nd position 40: Discharge oil passage 41: 1st charge oil passage 42: 2nd charge oil passage 43: Operating device 44: Speed change valve 44a: 1st position 44b: 2nd position 45: Running oil passage 45a: 1st running oil passage 45b: 2nd running oil passage 45c: 3rd running oil passage 45d: 4th running oil passage 45e: 5th running oil passage 46: Shuttle valve 47: Working oil passage 47a: Working oil passage 47b : Working oil passage 47c: Working oil passage 47d: Working oil passage 48: Anti-stall control valve 51: Control valve 51a: Boom control valve 51b: Bucket control valve 51c: Preliminary control valve 51f: Oil passage 52L: Traveling pump 52R: Running Pump 52a: Pressure receiving unit 52b: Pressure receiving unit 53: Operating device 54: Traveling operating member 55: Operating valve 55a: Operating valve 55b: Operating valve 55c: Operating valve 55d: Operating valve 56: Switch 56a: First electromagnetic valve 56b: First 2 Electromagnetic valve 57h: Speed change oil passage 57i: Speed change oil passage 58: Operation member 59: Operation valve 59a: Operation valve 59b: Operation valve 59c: Operation valve 59d: Operation valve 60: Engine 61: Cooling fan 63: Generator 63a : Connecting part 63b: Rotor 63c: Stator 63d: Water jacket 64: Hydraulic drive device 65: Housing 66: Battery 67: Power control device 67A: Inverter 67B: Inverter control unit 68a: Intermediate shaft 68b: Coupling 70: Work control Device 70a: Storage unit 70b: Power running torque setting unit 70c: Regenerative torque setting unit 70d: Operation control unit 70h: Switching change unit 77: Operation detection device 77A: First operation detection device 77B: Second operation detection device 85: Rotation detection Device 9 1: Detection sensor 97: Charge detection sensor 170h: Switching change unit 171: Pressure detection sensor

Claims (5)

With the aircraft
With the engine installed in the aircraft
A motor generator that operates as a motor to assist the driving of the engine and a power generation operation that operates as a generator by the power of the engine to generate electricity.
A hydraulic drive that can transmit the power of the engine and the motor / generator,
An operating member that operates the hydraulic drive system and
A control device that sets the timing of the assist operation based on the transition of the engine speed after operating the operation member, and
A working machine equipped with. The work machine according to claim 1, wherein the control device performs an assist operation after the engine speed changes from an increase to a decrease when the assist operation is performed. It is provided with an operating valve that sets the pilot pressure according to the operation of the operating member.
The work machine according to claim 1 or 2, wherein the hydraulic drive device has an output whose output changes according to a pilot pressure set by the operation valve. A pair of traveling devices provided on the aircraft and
A pair of traveling motors for driving the pair of traveling devices and
With
The work machine according to claim 3, wherein the hydraulic drive device is a pair of traveling pumps for driving the pair of traveling motors. Claims 1 to 4, wherein the control device starts the assist operation when the turning speed when the aircraft is turned by the pair of traveling devices is increased and the engine speed is increased and then decreased. The working machine described in either.

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