JP2002123327A - Getting-on/off passage opening and closing lever device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a getting-on/off passage opening and closing lever device which secure a large range for the lock position of a lock lever and does not impede a lock function even if the lock lever slightly moves when a driver gets on and off. SOLUTION: This getting-on/off passage opening and closing lever device for a construction machine which operates a limit switch as the lock lever which cuts off or opens a getting-on/off passage to a driver's seat by protruding into and retracting from the getting-on/off passage by rotating rotates and makes effective or ineffective the operation of an actuator for a working machine and for a travel by an operation lever through the operation of the limit switch; and the rotation part of the lock lever (28) is provided with a cam (32), which operates the limit switch (13).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a construction machine such as a hydraulic shovel and the like, for enabling or disabling the operation of a working machine or the like by an operation lever in accordance with the blocking or opening of the passage to a driver's seat. The present invention relates to an opening / closing lever device.

[0002]

2. Description of the Related Art In construction machines such as hydraulic excavators,
If the driver leaves the driver's seat or sits down while driving or checking or servicing, the actuator that drives the vehicle or drives the work equipment can be activated even if the driver accidentally touches the operation lever. An access passage opening / closing lever device has been devised to prevent this.

For example, according to Japanese Unexamined Utility Model Publication No. 62-12664, as shown in FIGS.
A horizontal rotating shaft 52 is provided below the driver's seat 51, a lever 53 is fixed to one end of the horizontal rotating shaft 52 on the driver's cab entrance side, and an actuator 54 of a limit switch 55 is fixed to the other end. ing. At this time, as shown in FIG.
When 3 is tilted forward to the L position, the doorway is shut off, and when it is raised to the H position, the doorway is opened, and in conjunction with this, the actuator 54 at the shaft end opens and closes the limit switch 55. Thereby, the pilot pressure for operating the hydraulic control valve is reduced by operating the electromagnetic control valve (not shown), and even if the operating lever 56 provided in front of the driver's seat 51 is operated, the hydraulic control valve does not operate. The actuator is not activated.

[0004]

However, in the technique disclosed in Japanese Utility Model Laid-Open Publication No. Sho 62-12664, the limit switch 55 switches between open and closed in a narrow range m near the upright H position of the lever 53. Therefore, the limit switch 55 can be easily opened and closed even if the driver touches the lever 53 when getting on or off, and the lever 53 only slightly moves from the upright H position. At this time, there is a problem that if the operation lever 56 is moved due to an accidental contact with a part of the body, the actuator is activated.

The present invention focuses on the above-mentioned conventional problems, and secures a large range of a lock position of a lock lever so that the lock function does not hinder the lock function even if the lock lever slightly moves when the driver gets on and off. The purpose is to provide.

[0006]

In order to achieve the above object, a first invention of a lift passage opening / closing lever device according to the present invention provides a lift passage opening / closing passage to a driver's seat by rotating. The limit switch is actuated in accordance with the rotation of the lock lever that protrudes and retreats to block or open the entrance passage, and the actuation of the limit switch enables or disables the operation of the work implement or the travel actuator with the operation lever. In the lift passage opening / closing lever device of the construction machine described above, a cam is provided on the rotating portion of the lock lever, and the limit switch is operated by the cam.

According to the first aspect of the present invention, since the operating range of the limit switch can be set wide by the cam, a large range of the lock position of the lock lever can be secured. Therefore, even if the lock lever moves slightly when the driver gets on and off, the lock function can be reliably performed without disturbing the lock function.

According to a second aspect, in the first aspect, an intermediate lever rotatable around a pin parallel to the rotation axis of the lock lever is provided between the rotation axis of the lock lever and the limit switch, One surface of the plate of the intermediate lever is in contact with the cam of the lock lever, and the other surface is in contact with the contact of the limit switch, so that the movement of the cam is transmitted to the contact of the limit switch.

According to the second aspect of the present invention, the cam and the contact of the limit switch contact one surface and the other surface of the plate of the intermediate lever, respectively, and the contact of the limit switch slides on the plate surface in the operating direction. Because of the movement, the lateral force acting on the contact is reduced, the movement of the contact accompanying the movement of the cam is smooth, and the durability of the limit switch can be improved.

In a third aspect based on the first or second aspect, the operating range of the limit switch is set to 15% to 85% of the entire stroke of the lock lever.

According to the third aspect of the invention, by setting the operation range of the limit switch to be wide during the entire stroke of the lock lever, the range of the lock position of the lock lever can be widened during the entire stroke. Some movements can be securely locked without disturbing the lock function.

In a fourth aspect based on the first or second aspect, the mounting position of the limit switch in the operating direction is adjustable by screwing the limit switch body.

According to the fourth aspect, the position adjusting mechanism of the limit switch is simple and easy to assemble, and the opening or closing operation range of the limit switch can be adjusted.
The range of the lock position of the lock lever can be easily adjusted. Thereby, the range of the lock position of the lock lever can be easily set so as to be adaptable to various types of models and work conditions, so that versatility can be improved.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIG.
This will be described with reference to FIG.

First, a control system of a pilot pressure operated hydraulic excavator to which the opening / closing passage opening / closing lever device of the present invention is applied will be described with reference to FIG. FIG. 1 is a control system diagram having a pilot type operation circuit of a hydraulic shovel. As shown in FIG. 1, a main pump 2 and a pilot pump 3 are driven by an engine 1. Discharge oil from the main pump 2 is supplied to an actuator 5 via a control valve 4. Further, the pilot oil discharged from the pilot pump 3 is reduced in pressure by the relief valve 6, and supplies pilot pressure to the pilot valve 8 through the solenoid valve 11 and the pilot circuit 7. Operation lever 9
By operating the control valve 4, the control valve 4 is switched by receiving pilot pressure from the pilot valve 8 to the operation units 4 a and 4 b, and supplies the discharge oil from the main pump 2 to the actuator 5.

The pilot circuit 7 has a two-position solenoid valve 11.
The solenoid 12 of the solenoid valve 11 is connected to a battery 14 via a normally closed (normally closed) contact (hereinafter referred to as an output contact) of a limit switch 13. That is, when the lock lever 28 is tilted forward, the limit switch 13 is inactive and the output contact is on. When the lock lever 28 is tilted backward, the limit switch 13 is active and the output contact is off. . When the output contact of the limit switch 13 is turned on or off, the solenoid valve 11 is energized or de-energized. In the energized state, the solenoid valve 11 is switched to the N position, and the pilot oil from the pilot pump 3 is supplied to the pilot circuit 7 via the pilot circuit 7. It is supplied to the valve 8, and switches to the M position in the non-energized state, and shuts off the pilot circuit 7.

Therefore, when the solenoid valve 11 is in the N position, a pilot pressure is generated in the pilot circuit 7. Therefore, when the operating lever 9 is operated, the pilot valve 8 is operated, and the pilot pressure is controlled by the operating portions 4a and 4a of the control valve 4. 4b, the control valve 4 is switched and the actuator 5 is driven. When the solenoid valve 11 is at the M position, no pilot pressure is generated in the pilot circuit 7, so that even if the operation lever 9 is operated, the actuator 5 is not driven. The operation of the limit switch 13 is switched between operation and non-operation by turning the lock lever 28, which will be described in detail below.

Next, a first embodiment of the entrance / exit passage opening / closing lever device according to the present invention will be described with reference to FIGS. 2 and 3 are a front view and a side view of the entrance / exit passage opening / closing lever device, respectively. As shown in FIGS. 2 and 3, a bracket 23 for mounting the operation lever 9 and the console box 22 is provided on the side of the driver's seat 21 in the left-right direction of the vehicle, and a plate 23 a is mounted on the bracket 23 along the left-right direction. ing. A bracket 24 for attaching a lock lever 28 is fastened to the plate 23a by a bolt 25. FIG. 4 is a sectional view taken along the line AA of FIG. 2, and FIG. 4 (a) shows a state where the lock lever 28 is at the position P1.
FIG. 4B shows the state at the position P4. FIG. 5 shows FIG.
FIG. As shown in FIGS. 4 and 5, the bracket 24 has a shaft 27 having a substantially horizontal axis.
Are rotatably fitted via bearings 26. A boss 29 of a lock lever 28 is fastened to one end of the shaft 27 by a bolt 30, and a spring receiving hole 31 is
The plate 31 having c is fixed. A substantially central portion of a plate 33 having a cam 32 formed at one end is fixed to the boss 29 of the lock lever 28, and a base end of a pipe 34 of the lock lever 28 is fixed to the other end of the plate 33. ing. A knob 28a shown in FIG. 2 is attached to the tip of the pipe 34.

A limit switch 13 is attached to the plate 23a of the bracket 23 by screwing, and the mounting position can be adjusted in the axial direction by screwing in. The limit switch 13 is fixed to the plate 23a by a nut 36. FIG.
As shown in the figure, the stroke s of the contact 13a is s <s1
The limit switch 13 is deactivated (output contact on) in the range, and activated (output contact off) in the range of s ≧ s1. Note that s2 is the maximum use stroke and s3 is the limit stroke.

FIG. 7 is a sectional view taken along the line CC of FIG. As shown in FIG. 7, a pin 37 is fixed to one surface 24a of the bracket 24, and the intermediate lever 3 is attached to the pin 37.
8 is rotatably fitted at the base end thereof. As shown in FIG. 4, the plate 39 of the intermediate lever 38 is located between the cam 32 and the limit switch 13,
9a is the cam 32, the other surface 39b is the limit switch 13
Can be brought into contact with each of the contacts 13a. Therefore, when the lock lever 28 is rotated backward, the cam 32 contacts the one surface 39a of the plate 39 to rotate the intermediate lever 38, and the other surface 39b of the plate 39 activates the contact 13a of the limit switch 13. Direction switch to activate the limit switch 13.

FIG. 8 is a Z view of FIG. As shown in FIG. 8, the other surface 24b of the bracket 24 opposite to the pin 37
Is provided with two stoppers 40 and 41 apart from each other,
The two stoppers 40 and 41 are respectively provided with the lock lever 2.
8 at both the initial position P1 and the stroke end position P4, the plate 31 comes into contact with both side surfaces 31a and 31b. Further, as shown in FIGS.
3, a spring receiving hole 23 drilled in a plate 23c provided in
A tension spring 42 is mounted between the lock lever 28 and the spring receiving hole 31c formed in the plate 31. When the lock lever 28 is at the initial position P1 and the stroke end position P4, the axis of the tension spring 42 is They are located on opposite sides of the axis. Thereby, the tension spring 4
2 holds the lock lever 28 at the initial position P1 or the stroke end position P4.

Next, the operation and effect of the first embodiment will be described with reference to FIGS. 1, 3, 4 and 6. As shown in FIG. 3, when the operator sits down and tilts the lock lever 28 forward to the P1 position when starting operation, the lock lever 28 is held at the P1 position by the tension spring 42,
The pipe 34 of the lock lever 28 is connected to the access passage R shown in FIG.
The operator cannot get off in this state. When the lock lever 28 is in the P1 position, FIG.
As shown in FIG.
9a is in contact with the cam 32, but a predetermined gap e is provided between the other surface 39b and the contact 13a of the limit switch 13.
Therefore, as shown in FIG.
Is inactive, and the output contact is on. When the output contact of the limit switch 13 is turned on, as shown in FIG. 1, the solenoid valve 11 is in the N position when energized, and the actuator 5 is driven when the operation lever 9 is operated.

When the lock lever 28 is pulled up from the position P1 to the backward tilt side, the cam 32 contacts the one surface 39a of the plate 39 and the intermediate lever 38 as shown in FIG.
And when the lock lever 28 comes to the P2 position,
The gap between the other surface 39b of the plate 39 and the contact 13a of the limit switch 13 is zero. Furthermore, lock lever 2
6, the other surface 39b of the plate 39 keeps pushing the contact 13a of the limit switch 13 in the axial direction, and when the lock lever 28 comes to the P3 position, the contact 13a in FIG. Is s1, the limit switch 13 is activated, and the output contact is turned off.

Further, while the lock lever 28 is being pulled up to the position P4 at the stroke end, the other surface 39b of the plate 39 keeps pushing the contact 13a of the limit switch 13 in the operating direction, and the lock lever 28 is moved to the position P4 at the stroke end. When it comes to the position, the displacement stroke of the contact 13a becomes s2, during which the output contact of the limit switch 13 is kept off. When the output contact of the limit switch 13 is turned off, as shown in FIG.
Is in the M position in the non-energized state, and the actuator 5 is not driven even if the operation lever 9 is operated.

While the lock lever 28 moves from the P3 position to the P4 position, the output contact of the limit switch 13 is kept off, so that the rotation range in which the operation of the operation lever 9 can be locked by the lock lever 28 is large. Even if 28 moves from the P4 position to the P3 position, the output contact of the limit switch 13 will not be turned on.
Therefore, even if the lock lever 28 moves to some extent, the work machine or the traveling actuator does not operate without hindering the lock function.

Since the movement of the cam 32 of the lock lever 28 is transmitted to the contact 13a of the limit switch 13 via the intermediate lever 38, the lateral force acting on the contact 13a is small, and the contact 13a Axial direction (operating direction)
Movement is smooth and durable. Further, since the limit switch 13 has its axial mounting position adjustable by screwing in, the position adjusting mechanism is simple and easy to assemble, and the stroke of the contact 13a of the limit switch 13 by the cam 32 is achieved. The amount can be adjusted, and the lock range of the lock lever 28 can be easily adjusted. When the lock lever 28 reaches the position P4, the lock lever 28 is held in a state where the entrance / exit passage R is opened by the tension spring 42, so that the operator can easily get off the vehicle, and when the vehicle gets off the vehicle, the lock lever 28 is slightly released. Even if it is moved, the operation of the actuator by the operation lever can be reliably prevented.

Next, a second embodiment will be described with reference to FIGS. FIG. 9 is a side view of a main part of the entrance / exit passage opening / closing lever device. FIG. 10 is a sectional view taken along line DD of FIG. Second
In this embodiment, as shown in FIGS. 9 and 10, in the first embodiment, the limit switch 13 is a roller contact-type limit switch 13A, and the cam 32 is a cam 32A that contacts the roller contact 13b of the limit switch 13A. , The intermediate lever 38 is omitted.

The bracket 24 supporting the shaft 27 of the lock lever 28A is mounted on the plate 23b of the bracket 23.
Are fastened by bolts 25A. Similarly, a limit switch 13A is provided on the plate 23b.
It is attached by a bolt 36A so that the position can be adjusted in the operation direction by c. Then, when the lock lever 28A is rotated, the cam 32A comes into contact with the roller contact 13b of the limit switch 13A, and pushes the roller contact 13b in the operating direction while rolling to actuate the limit switch 13A. I have. The other configuration is the same as that of the first embodiment, and the description is omitted.

According to the second embodiment, when the lock lever 28A is rotated as shown in FIG.
Comes into contact with the roller contact 13b of the limit switch 13A and rolls, so that no lateral force acts on the roller contact 13b, the axial movement becomes smooth, the operation of the limit switch 13A is reliable, and the durability is improved. Get higher. In addition, since there is no intermediate lever 38, the configuration can be simplified. Other functions and effects are the same as those of the first embodiment.

In the embodiments described above, in the working machine and the traveling control circuit using the pilot type operation circuit,
Although the example in which the cutoff or the communication of the pilot circuit is switched by the limit switch has been described, the present invention is not limited to such a pilot hydraulic circuit, and the electric operating lever and the electromagnetic switching valve may be controlled by a controller such as a computer. Of course, the present invention can also be applied to an electric control circuit controlled by the control lever, and it is also possible to switch whether the control of the electromagnetic switching valve by the operation lever is enabled or disabled by the limit switch signal. Good.

As described above, according to the present invention, since the cam is provided on the rotating portion of the lock lever and the operation range of the limit switch can be set arbitrarily, a large range of the lock position of the lock lever can be secured. Therefore, even if the lock lever slightly moves when the driver gets on and off the vehicle, the lock function can be securely locked without disturbing the lock function. Further, an intermediate lever is provided between the cam of the lock lever and the contact of the limit switch, and the movement of the cam is transmitted to the contact of the limit switch through the intermediate lever, whereby a lateral direction acting on the contact is provided. By reducing the force, the movement of the contact of the limit switch in the operation direction accompanying the movement of the cam becomes smooth, and the durability of the limit switch can be improved. Further, by using a roller contact type as the limit switch, the movement of the contact of the limit switch in the operation direction can be further smoothed, and the intermediate lever can be made unnecessary and simple.

Further, since the mounting position of the limit switch in the operating direction can be adjusted by screwing or the like, the position adjusting mechanism is simple, the mounting is easy, and the operating position of the limit switch can be adjusted. The locking range of the lever can be easily adjusted.

[Brief description of the drawings]

FIG. 1 is a control system diagram having a pilot-type operation circuit to which an entrance / exit passage opening / closing lever device according to the present invention is applied.

FIG. 2 is a front view of the entrance / exit passage opening / closing lever device of the first embodiment.

FIG. 3 is a side view of the entrance / exit passage opening / closing lever device of the first embodiment.

4A is a cross-sectional view taken along the line AA of FIG. 2, wherein FIG. 4A shows a state when the lock lever is at a position P1, and FIG. 4B shows a state when the lock lever is at a position P4.

FIG. 5 is a sectional view taken along line BB of FIG.

FIG. 6 is an operation diagram of a limit switch.

FIG. 7 is a cross-sectional view taken along the line CC of FIG.

FIG. 8 is a Z view of FIG. 7;

FIG. 9 is a side view of a lift passage opening / closing lever device according to a second embodiment.

FIG. 10 is a sectional view taken along line DD of FIG. 9;

FIG. 11 is a side view of a conventional lock lever device.

FIG. 12 is a perspective view of a part Q in FIG. 11;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Engine, 2 ... Main pump, 3 ... Pilot pump, 4 ... Control valve, 5 ... Actuator, 6
... Relief valves 6, 7 ... Pilot circuit, 8 ... Pilot valve, 9 ... Operation lever, 10 ... Tank circuit, 11 ... Electromagnetic valve, 12 ... Power circuit, 13, 13A ... Limit switch, 13a, 13b ... Contact, 13c ... Long hole, 14 ... Battery, 21 ... Driver seat, 22 ... Console box, 23 ... Bracket, 23a, 23b, 23c ... Plate, 23d ... Spring receiving hole, 24 ... Bracket, 25,
25A bolt, 26 bearing, 27 shaft 28, 2
8A: Lock lever, 29: Boss, 30: Bolt, 31
... Plate, 31a ... Spring receiving hole, 32, 32A ... Cam, 33 ... Plate, 34 ... Pipe, 36 ... Nut, 3
7 ... pin, 38 ... intermediate lever, 39 ... plate, 39
a, 39b: front surface of the plate 39, the other surface, 0, 41: stopper, 42: tension spring.

Claims (4)

[Claims] A limit switch is actuated in accordance with the rotation of a lock lever that projects / retreats into / from a driver's seat by turning and protruding / retreating from / to a driver's seat to shut off / open the driver's seat, and the limit switch is actuated. In a lift device for opening / closing a passage of a construction machine in which the operation of a working machine or a travel actuator by an operation lever is enabled or disabled, a cam (32) is provided at a rotating portion of a lock lever (28), and the cam is provided.
An on / off passage opening / closing lever device, wherein the limit switch (13) is operated by (32). 2. The opening / closing passage opening / closing lever device according to claim 1, wherein the rotation shaft (27) of the lock lever (28) and the limit switch (13).
A pin parallel to the rotation axis (27) of the lock lever (28).
An intermediate lever (38) that is rotatable around (37) is provided, and one surface (39a) of the plate (39) of the intermediate lever (38) is attached to the cam (32) of the lock lever (28), and the other surface ( 39b) with the limit switch (1
A lift passage opening / closing lever device wherein the movement of the cam (32) is transmitted to the contact (13a) of the limit switch (13) by bringing the contact (13a) into contact with the contact (13a). 3. The opening / closing passage opening / closing lever device according to claim 1, wherein the operating range of the limit switch is set to 15% to 85% of the entire stroke of the lock lever. Getting on / off passage opening and closing lever device. 4. The access passage opening / closing lever device according to claim 1, wherein an assembling position of the limit switch in the operating direction of the limit switch is adjustable by screwing the limit switch body. Open / close lever device.