JPH0325210Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a control device for a hydraulically driven working machine equipped with a hydraulic actuator, such as a hydraulically driven vehicle-mounted crane.

(Prior Art) This type of hydraulically driven working machine, such as a vehicle-mounted crane, is provided with various operating levers for operating the crane and an accelerator operating lever for controlling the working speed of the crane operation. In conventional crane control systems, when operating the crane and operating the accelerator at the same time, it is necessary to operate the crane operating lever and the accelerator operating lever at the same time, making the operation of each operating lever complicated. It was hot. In particular, when one worker needs to simultaneously operate three or more operating levers including the accelerator operating lever, it becomes extremely difficult to operate each of the operating levers.

Against this background, the applicant came up with the idea of eliminating the complexity of lever operation by making it possible to simultaneously operate the accelerator in conjunction with the operation of an operating lever other than the accelerator operating lever. A technically specific version has already been filed (Utility Application No. 109365, 1983).

To briefly explain the control device of this earlier application, the operating lever for switching the hydraulic switching valve can be moved beyond the lever position where the switching operation of the hydraulic switching valve is completed to an overstroke range, and in this overstroke range, The accelerator operating member can be operated in conjunction with the lever operation of the operating lever. As a specific example, the operating lever is connected to the accelerator operating member via a pantograph-type link mechanism.

However, in this previously filed application, the operating lever and the accelerator operating member are interlocked and connected via a pantograph-type link mechanism, so the sliding resistance at the link connection is relatively large, and the number of parts is comparatively large. Due to the large number of targets, the weight of the operating section increases, and a relatively large operating force is required.
There was room for improvement in this respect.

(Purpose of the invention) The present invention was made in view of the above points, and its purpose is to provide a control device for a hydraulically driven working machine that has a simple configuration and reduces the operating force of the operating lever. That is.

(Means for Achieving the Object) In the present invention, as a means for achieving the above object, (1) In the invention according to claim 1, the device is driven by an engine and its discharge amount is adjusted by adjusting the output of the engine. A hydraulic pump that is controlled by a hydraulic pump, a hydraulic actuator that operates by receiving pressure oil from the hydraulic pump, and a hydraulic control section that controls supply of pressure oil to the hydraulic actuator, and a spool of the hydraulic control section. The switching operation is controlled by a hydraulic control unit-side operating lever that is swingably supported via a support shaft near the operating end of the spool and operatively connected to the spool via a coupling device, and a hydraulic control unit-side operating lever that is separated from the hydraulic control unit. In the hydraulically driven working machine, the hydraulic pressure is controlled by a non-hydraulic control section side operating lever which is swingably supported via a support shaft at a position in which the hydraulic control section side operating lever is interlocked with the hydraulic pressure control section side operating lever. A spring is installed so that the connecting device that interlocks and connects the control unit-side operating lever and the spool can be moved beyond the first operating lever position where the switching operation of the spool is completed to the second operating lever position in the overstroke range. The hydraulic control section side operating lever has a cam having a cam surface of an appropriate shape, and one end of the cam is located at a position close to and opposite to the cam surface of the cam. A swing arm connected to an accelerator operating member for adjusting the output of the engine is attached to each of the swing arms, and the cam and the swing arm are connected to each other until the displacement of the non-control section side operating lever reaches the vicinity of the first operating lever position. If the disengaged state with the arm is maintained and the displacement of the non-control section side operating lever is between a position near the first operating lever position and an overstroke range, the cam and the swing The present invention is characterized in that the arms are configured to engage with each other so that the operation lever on the opposite side of the control section is interlocked with the accelerator operation member.

(Function) In the present invention, by the above-mentioned means, each operating lever on the control section side or the non-control section side is operated within a range close to the first operating lever position where the switching operation of the hydraulic control section is completed. At times, only the operation of the hydraulic actuator can be switched, and when operating each operating lever in an overstroke range from near to the first operating lever position to beyond this, a The cam engages with the swing lever and the accelerator operating member interlocks with the operating lever, making it possible to control the operating speed of the hydraulic actuator by lever operating the operating lever. By selectively using the operating ranges of the hydraulic actuators, it is possible to independently switch the operation of the hydraulic actuator and control its operating speed.

(Embodiment) Hereinafter, a preferred embodiment of the present invention will be described with reference to FIGS. 1 to 4.

1 and 2 show an operating section of a hydraulically driven working machine (hydraulicly driven vehicle-mounted crane) according to an embodiment of the present invention. This vehicle-mounted crane is designed to control the speed of crane work by controlling the output of the engine. In Figures 1 and 2, reference numeral 1 indicates the crane base, and 2, 2, etc. indicate the crane operation. Hydraulic switching valves (corresponding to the hydraulic control unit within the scope of the utility model registration claim) for switching (boom extension/retraction operation, winch operation, etc.) and extending/retracting the outriggers, and six pieces are stacked in the vertical direction. It is located in the state.

Various operating levers for operating the crane in the above operating section, ie, boom extension/retraction operating levers 3A ₁ , 3
A ₂ , winch operation levers 3B ₁ , 3B ₂ , boom hoisting operation levers 3C ₁ , 3C ₂ , boom rotation operation levers 3D ₁ , 3D ₂ , and two outrigger operations for extending and retracting the outriggers. A pair of levers 3E ₁ , 3E ₂ and 3F ₁ , 3F ₂ are used, and each pair of operating levers 3A ₁ , 3A ₂ . . . is installed separately on both sides of the crane base 1.

These operation levers 3A ₁ , 3A ₂ . . . are fixed to the vehicle side via predetermined lever bases 41, 42, 43, respectively. That is, six operating levers (hereinafter referred to as non-control unit side operating levers) arranged on the left side of the vehicle 3A ₂ , 3B ₂ , 3C ₂ , 3D ₂ ,
Among the 3E ₂ and 3F ₂ , the four operating levers 3A ₂ , 3B ₂ , 3C ₂ , and 3D ₂ for operating the crane are first lever bases each having a U-shaped cross section as shown in FIGS. 1 and 3, respectively. 41, and the outrigger operating levers 3E ₂ and 3F ₂ are each directly fixed to a third lever base 43 which is shorter than the first lever base 41. These four first lever bases 41, 41... and two third lever bases 43
are vertically stacked and pivotably supported by a common support shaft 12, and each of the operating levers 3A ₂ , 3B ₂ , . . . can be independently rotated left and right. ing.

On the other hand, there are six operating levers located on the right side of the vehicle (hereinafter referred to as control unit side operating levers).
Among 3A ₁ , 3B ₁ , 3C ₁ , 3D ₁ , 3E ₁ , 3F ₁ ,
The outrigger operating levers 3E ₁ and _{3F 1 are} fixed to the third lever base 43 in _the same manner as the left operating levers 3E ₂ and 3F ₂ . On the other hand, four operating levers 3A ₁ , 3B ₁ , 3C ₁ ,
As shown in FIGS. 1 and 3, the 3D ₁ is fixed to a second lever base 42 having a U-shaped cross section via an overstroke permitting mechanism 44, which will be described later, and which is connected to the spool 5 of the hydraulic control section 2. ing. The second lever bases 42, _{42 ,} . The operating levers 3A ₁ , 3 are supported pivotably in a vertically stacked manner by a support shaft 13 .
B ₁ , . . . are each freely rotatable in the left and right directions.

The pair of left and right operating levers 3A, 3B, .
By communicating with B, 4C, 4D, 4E, and 4F, when either of the pair of left and right operation levers is operated, the corresponding hydraulic control section 2 is switched to perform a predetermined crane operation or outrigger operation. I am learning how to do it.

In this control device, each operation lever 3A ₁ , 3A ₂ , 3B ₁ , 3B ₂ , 3C ₁ , 3 for crane operation
By selecting the operating range _of C ₂ , 3D ₁ , and 3D _{2 ,} the speed of crane work is simultaneously controlled. will be explained with reference to FIGS. 3 to 5.

First, on the control unit side operation lever 3A ₁ side,
As shown in FIG. 3, the operating lever _3A1 and the second
The operating lever _3A1 can be connected to the lever base 42 via a connecting device 44, which will be described later.
From the neutral position N where the hydraulic control unit 2 is held in the neutral position, the switching operation of the hydraulic control unit 2 is completed and the spool 5 reaches the stroke end beyond the first operating lever position L ₁ , R ₁ to reach the overstroke region. The lever is movable up to the second operating lever position L ₂ , R ₂ , and the speed of crane operation is controlled in this overstroke range. The connecting device 44 includes a rod 61 which is always urged to protrude outward by a spring 60 housed in a casing 63, as shown in FIG.
have. This coupling device 44 is connected to the casing 6
Attach the operating lever 3A ₁ to the end surface of the rod 3 on the side opposite to the rod 61.
Further, the second lever bases 42 are respectively fixed to the end faces on the rod 61 side. Also, the spool 5 of the hydraulic control section 2 is attached to the tip of the rod 61.
are connected, and furthermore, the spring 60
The spring force of is set larger than the spring force of a return spring (not shown) of the hydraulic control section 2. Therefore, when the operating lever 3A ₁ is rotated within the range from the neutral position N to the first operating lever positions L ₁ and R ₂ , the hydraulic control section 2 is switched. On the other hand, the operating lever 3
When A ₁ is operated further outward than the first operation lever position L ₁ , R ₁ , the spool 5 has reached the stroke end, so the coupling device 4
4 is compressed, and the operating lever 3A ₁ is moved to the first operating lever position L ₁ while the spool 5 of the hydraulic control unit 2 is positioned at the stroke end.
It is possible to operate within the range of R ₁ and the second operating lever position L ₂ , R ₂ .

On the other hand, on the first lever base 41 side, the non-control section side operation lever _3A2 is set to the same operating position in conjunction with the operation of the control section side operation lever _3A1 . The engine output can be adjusted in conjunction with the operation of the control section side operating lever _3A1 or the non-control section side operating lever _3A2 in the overstroke range. That is, a cam 21 made of a substantially triangular plate and having a cam surface 22 on one side is mounted on the support shaft 12 portion of the first lever base 41, with the cam surface 22 facing outward and the cam surface 22 facing outward. It is attached so that the top facing the center of rotation is the center of rotation. Accordingly, when the operating lever 3A ₁ or 3A ₂ is at the neutral position N, the cam ₂₁ moves to the neutral position _lN shown by the solid line in FIG. Operation lever 3A ₁ or 3A ₂
is at the first operating lever position L ₁ , R _{1 ,} the first cam position l ₁ , shown by the chain line in FIG.
r ₁ , and when the operating lever 3A ₁ or 3A ₂ is in the second operating lever position L ₂ or R ₂ , the fourth
The second cam position is shown in solid and dashed lines in the figure.
They are positioned at l ₂ and r ₂ respectively.

Note that the cam surface 22 of this cam 21 is
The cam surface 22 is
It is an inclined surface that is recessed and inclined toward the center in the direction of the cam surface, and the positions near the tops 23, 23 are large diameter portions 22a, 22a that become engaging portions for the roller 26, as will be described later. Further, a position closer to the center is a small diameter portion 22b.

Further, a roller 26 is disposed immediately before the cam surface 22 of the cam 21 and is attached to one end 25a of a swing arm 25 rotatably supported by a support shaft 14. This roller 26 has an appropriate length and is attached to a cam 2 provided on a total of four first lever bases 41, 41, . . . which are stacked vertically as shown in FIG.
1, 21, . . . are arranged in the vertical direction so as to be able to engage with each other.

Further, at the other end 25b of the swing arm 25, one end of an accelerator wire 30 (corresponding to the accelerator operating member in the scope of the utility model registration claims) is connected to an accelerator lever (not shown) of the engine (not shown). connected. The swing arm 25 is rotatable about the support shaft 14 between a low speed lever position _p1 as shown in FIG. 3 and a high speed lever position _p2 shown in solid line in FIG. The swing arm 25 is always urged toward the low speed lever position _p1 by a spring 27. Further, the relative mounting positions of the swing arm 25 and the accelerator wire 30 are set so that the engine is operated at a predetermined rotation speed at a low speed when the swing arm 25 is positioned at the low speed side lever position _p1 . .

Furthermore, the relative relationship between the cam 21 and the swing arm 25 is set as follows. That is,
As shown in FIG. 3, the cam 21 is in the neutral position.
l When set to _N , the above roller 2
When the cam 21 is positioned at the first cam position l ₁ , r ₁ as shown by the chain line in FIG. 22a, 22a and roller 26 come into contact for the first time. Further, when the cam 21 is rotated beyond the first cam position l ₁ , r ₁ to the second cam position l ₂ , r ₂ , the cam surface 22 of the cam 21 causes the roller 26 to is pushed out in front of the cam,
As a result, the swing arm 25 is rotated from the low-speed lever position _p1 to the high-speed lever position _p2 . Therefore, the accelerator wire 30
When the cam 21 is rotated from the first cam position l ₁ , r ₁ to the second cam position l ₂ , r ₂ , the engine speed is increased.

Next, to explain the operating method and function of the control device of this embodiment, when performing crane work (for example, raising/lowering or extending/contracting the boom, operating the winch, etc.) at low speed, the corresponding operation as shown in Fig. 3 will be explained. For example, move the operating lever for boom extension/retraction 3A ₁ or 3A ₂ to the first operating lever position (L ₁ or
At the _R1 position, the cam 21 on the operating lever _3A2 side is pivoted to a position where it does not press the roller 26 of the swing arm 25, which is positioned at the low speed lever position _p1 , and is held there. The switching valve 2 is operated to enable crane work (boom extension and contraction) to be performed at low speed. still,
When you want to speed up crane work, you can increase the speed of the crane work by operating a separately installed accelerator lever (not shown). ), it is difficult for one person to operate the two operating levers and the accelerator lever at the same time.
However, according to the illustrated control device, when increasing the speed of the crane operation from a low speed to an appropriate speed, the operation lever 3A ₁ or 3A ₂ is moved further outward from the first operation lever position L ₁ , R ₁ where the crane operation is being performed. With a simple operation, the cam 21 moves the swing arm 25 to the low speed lever position.
It is possible to speed up the crane work by rotating the lever from _p1 to the high speed side lever position _p2 and using the swing arm 25 to pull the accelerator wire 30 toward the engine speed increasing side. Furthermore, even when the crane is being operated in combination (operating two operating levers at the same time), it is possible to further pivot either one of the operating levers or both in the overstroke direction. This has the effect of easily speeding up crane operations even during complex operations.
Note that when the operating lever is returned from the overstroke range to the first operating lever position L ₁ , R ₁ or the neutral position N, the accelerator is returned to the low speed position.

In addition, in this embodiment, each operating lever 3A ₁ ,
When the displacement of 3A ₂ , 3B ₁ , 3B ₂ , ... is within the overstroke range from the first operating lever position L ₁ , R ₁ , the cam 21 and the swing arm 25 engage and the operating lever 3A ₁ , 3A ₂ , 3B ₁ , 3
B ₂ , .
The cam 21 and the swing arm 25 engage with each other before the displacement of each operating lever 3A ₁ , 3A ₂ , 3B ₁ , 3B _{2 , .} , 3B ₁ , 3B ₂ , . . . can also be configured to operate in conjunction with the accelerator operating member.

(Effects of the invention) Next, to explain the effects of the invention, the invention provides a hydraulic pump that is driven by an engine and whose discharge amount is controlled by adjusting the output of the engine, and a hydraulic pump that extracts pressure oil from the hydraulic pump. The hydraulic actuator is operated by a hydraulic actuator, and a hydraulic control unit that controls the supply of pressure oil to the hydraulic actuator, and the switching operation of the spool of the hydraulic control unit is controlled by a support shaft located near an operating end of the spool. a hydraulic control section-side operating lever that is pivotably pivoted via a support shaft and operatively connected to the spool via a coupling device; In a hydraulically driven work machine, the operation is performed by a counter-hydraulic control section side operating lever interlockingly connected to a control section side operating lever, and a coupling device for interlockingly connecting the hydraulic control section side operating lever and the spool is connected to the spool. The hydraulic control section is constructed of an elastic coupling mechanism with a spring interposed therein so as to be able to move beyond the first operating lever position where the switching operation is completed to the second operating lever position in the overstroke range. The side operating lever has a cam having a cam surface of an appropriate shape, and at a position close to and facing the cam surface of the cam, there is a swing arm whose one end is connected to an accelerator operating member for adjusting the output of the engine. are attached to each of the cams and the swing arm, and the disengaged state between the cam and the swing arm is maintained until the displacement of the operation lever on the side opposite to the control section reaches near the position of the first operation lever, whereas The displacement of the control unit side operating lever is
When the operating lever is located between a position close to the operating lever position and an overstroke range, the cam and the swing arm are engaged with each other, and the operating lever on the opposite side of the control section is configured to interlock with the accelerator operating member. It is characterized by the presence of

Therefore, according to the control device for a hydraulically driven work machine of the present invention, since the interlocking mechanism for interlocking the accelerator operating member of the engine with the lever operation of the operating lever is constituted by a cam mechanism, the interlocking mechanism is Compared to a pantograph-type link mechanism, there is less sliding resistance in the sliding part, and the reduced number of parts reduces the operating weight, making it easier to adjust engine output using the operating lever. You can get the practical effect of being able to do it by force.

Further, the hydraulic control unit side operating lever and the spool of the hydraulic control unit can be moved beyond the first operating lever position where the switching operation of the spool is completed to the second operating lever position in the overstroke range. Since they are interlocked and connected by a connecting device constituted by an elastic connecting mechanism with a spring interposed therebetween, the construction is simple and the entire device can be reduced in power.

Furthermore, by using a simple mechanism that combines a cam and a swing arm, it is possible to control the work equipment and the engine at the same time with a single control lever and lever operation. This also has the effect that the structure can be easily simplified and costs can be reduced accordingly.

In addition, since the cam and swing arm that control the engine in conjunction with the operation of the control lever are provided on the non-control side control lever side, the control This also has the effect of simplifying the structure on the side and improving the degree of freedom in the arrangement of control equipment.

[Brief explanation of drawings]

FIG. 1 is a front view of the main parts of the operating section of a vehicle-mounted crane according to an embodiment of the present invention, FIG. 2 is a view taken from the - arrow in FIG. 1, and FIG. FIG. 4 is an enlarged view of the main part, FIG. 4 is a state change diagram of FIG. 3, and FIG. 5 is a structural explanatory diagram of the coupling device mechanism shown in FIG. 1. 1...Crane base, 2...Hydraulic control unit, 3
A ₁ , 3A ₂ ... Control unit side operating lever, 3B ₁ , 3B ₂
...Operation lever on the opposite control section side, 4A, 4B...Operation rod, 21...Cam, 22...Cam surface, 25...
... Swing arm, 26 ... Roller, 30 ... Accelerator operation member, 41, 42, 43 ... Lever base, 44 ... Connection device.

Claims (1)

[Claims for Utility Model Registration] 1. A hydraulic pump that is driven by an engine and whose discharge amount is controlled by adjusting the output of the engine, a hydraulic actuator that operates by receiving pressure oil from the hydraulic pump, and Hydraulic control unit 2 that controls pressure oil supply to the hydraulic actuator
, and the switching operation of the spool of the hydraulic control unit 2 is controlled by a hydraulic pressure that is pivotably pivoted via a support shaft at a position near the operating end of the spool and operatively connected to the spool via a coupling device. The hydraulic control unit side operating levers 3A ₁ , 3B ₁ , . . . are swingably supported via a support shaft at a position apart from the hydraulic control unit ₂ .
3B ₁ , . . . In the hydraulically driven working machine _, the hydraulic control section side operation levers 3A ₂ , 3B ₂ , . . . ₁ ,... and the connecting device 44 that interlocks the spool to the first operation lever position where the switching operation of the spool is completed.
It is composed of an elastic coupling mechanism with a spring interposed so that it can be displaced beyond L ₁ and R ₁ to the second operating lever position L ₂ and R ₂ in the overstroke range, and the hydraulic control section side operation is The levers 3A ₁ , 3B ₁ , . . . each have a cam 21 having a cam surface 22 of an appropriate shape, and one end of the cam 21 is positioned close to and opposite to the cam surface 22 to adjust the output of the engine. A swing arm 25 connected to an accelerator operating member 30 is attached to each of the swing arms 25, and the displacement of the non-control section side operating levers 3A ₂ , 3B ₂ , . . . is in the vicinity of the first operating lever position L ₁ , R ₁ The cam 21 and _the swing arm ₂₅ are kept in a disengaged state until they reach the first operating lever position L. ₁ , R ₁ and between the overstroke range, the cam 21 and the swing arm 25 engage with each other, and the non-control section side operating levers 3A ₂ , 3B ₂ , . . . A control device for a hydraulically driven working machine, characterized in that it is configured to interlock with an accelerator operating member 30. 2. The cam 21 has a cam surface 22 having a large diameter portion 22a located radially far from the support shaft 12 and a small diameter portion 22b located close to the support shaft 12, and the non-control portion side operation levers 3A ₂ , 3B The swing arm 25 is configured to rotate in conjunction with the operation of the cam surface 22 when the non-control section side operation levers 3A ₂ , 3B _{2 ,} ... are in the neutral position. Small diameter portion 22b of
and are in a state of disengagement with the cam surface 22 until the non-control section side operating levers 3A ₂ , 3B ₂ , . . . reach the vicinity of the first operating lever positions L ₁ , R ₁ . 2. The control device for a hydraulic working machine according to claim 1, wherein the control device is configured to maintain the following. 3 The hydraulically driven working machine is a crane, and the hydraulic control section 2 and the control section side operating lever 3 of the crane are
A ₁ , 3B ₁ , _{. .} . are connected via coupling devices 44, 44, . , the control section side operating levers 3A ₁ , 3B ₁ , ... are the operating rods 4A, 4B,
... connected to the cam 21 via...
2. The control device for a hydraulically driven working machine according to claim 1, wherein the swing arm 25 is rotatably supported in a state facing the cam 21.