JPH0221603Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a hydraulic drive device, and particularly to a hydraulic drive device suitable for vertically moving the bit of a crawler drill.

(Prior Art) An example of a conventional crawler drill is shown in FIG. 4, in which a guide cell 02 is vertically supported on a truck 01.
A drifter 03 is attached so as to be slidable up and down, and a rock 06 is drilled by applying rotational force and striking force to a bit 05 which is interlocked with the drifter 03 via a rod 04. This drifter 03 is moved up and down along the guide cell 02 via a roller chain (not shown) installed within the guide cell 02 by driving a hydraulic motor 07 .

(Problems to be solved by the invention) When performing drilling work using the crawler drill described above, the feeding speed of the bit 05 by the hydraulic motor 07 must be appropriately selected depending on the rock quality, and the crushing In order to remove the crushed rock powder using compressed air, it is necessary to perform a flushing operation in which the bit 05 is moved up and down at high speed within the hole. Therefore, bit 0 due to hydraulic motor 07
The feed speed of No. 5 can be finely adjusted, and it is necessary to switch between high and low speeds. In addition, the bedrock 06 is generally not homogeneous, and there are soft areas such as clay and crushed layers.
Since there are holes 8 and cavities 09, if the bit 05 hits these layers of low resistance during the drilling process, the bit 05 will move forward rapidly, causing the hole to bend and there is a risk that the rod 04 will not come out. There is.
Therefore, during drilling work, the operator should carefully operate the hydraulic motor 07 while anticipating the conditions inside the rock 06.
Since it is necessary to adjust the speed of the machine, there is a problem in that it requires skill and is tiring.

(Means for solving the problems) The present invention was proposed to solve the above problems, and it allows fine adjustment of speed, switching between low speed and high speed, and variable load. The purpose of this system is to provide a hydraulic drive system that does not suddenly change speed even when the engine is moving. These are connected in series in this order so that the variable flow rate control valve and the directional switching valve are supplied with pressure oil discharged from the second hydraulic pump via the directional switching valve for speed switching. The hydraulic drive device is characterized in that it is connected in such a way that it can

(Embodiment) Hereinafter, the present invention will be specifically explained with reference to an embodiment shown in FIGS. 1 to 3.

In Figures 1 to 3, 1 is a hydraulic motor for moving a hydraulic drifter etc. back and forth;
2 is a first hydraulic pump, 3 is a second hydraulic pump, and these are interlocked and connected to a motor M. 4
is a remote controlled variable flow control valve,
5 is a remote-controlled 6-port 3-position feed directional control valve, 6 is a remote-controlled 3-port 2-position speed control directional valve, and 7 is a remote-controlled 3-port 2-position control valve. 8 is a directional control valve for impact; 8 is a check valve;
9 and 10 are relief valves, 11 is a hydraulic drifter, 1
2 is a drain tank. These are connected in series in this order so that the pressure oil discharged from the first hydraulic pump 2 is supplied to the hydraulic motor 1 for feeding via the variable flow rate control valve 4 and the directional switching valve 5 for feeding,
A connection is made between the variable flow rate control valve 4 and the directional switching valve 5 for feeding so that the pressure oil discharged from the second hydraulic pump 3 can merge through the directional switching valve 6 for speed switching and the check valve 8. has been done.

However, in the neutral state shown in Figure 1,
The pressure oil discharged from the first hydraulic pump 2 passes through the variable flow rate control valve 4 and the feed direction switching valve 5 and is discharged into the drain tank 12, and the pressure oil discharged from the second hydraulic pump 3 passes through the variable flow rate control valve 4 and the directional switching valve 5 for feeding, and is discharged into the drain tank 12. The drain tank 12 is passed through the directional switching valve 6 for use and the directional switching valve 7 for impact.
is discharged.

When moving the bit forward or backward at low speed,
As shown in FIG. 2, the speed switching directional control valve 6 is switched to the low speed position 6a. Then, when the feed directional switching valve 5 is switched to the forward position 5a or the reverse position 5b, only the pressure oil discharged from the first hydraulic pump 2 passes through the variable flow rate control valve 4 and the feeding directional switching valve 5. The hydraulic oil is supplied to the hydraulic oil motor 1 for feeding, and this hydraulic motor 1 rotates forward or reverse at low speed.
The bit moves forward or backward at low speed. At this time, by operating the variable flow rate control valve 4 by remote control, the amount of oil passing through it can be adjusted and the rotational speed of the hydraulic motor 1 for feeding can be controlled. On the other hand, at this time, by switching the impact direction switching valve 7 as shown in the figure, the drifter 11 can be operated to drill into the rock.

When moving the bit forward or backward at high speed,
As shown in FIG. 3, the speed switching directional control valve 6 is switched to the high speed position 6b. Then, the pressure oil discharged from the second hydraulic pump 3 passes through the directional switching valve 6 for speed switching and the check valve 8 and is transferred to the first hydraulic pump 2.
The pressure oil discharged from the feeder joins upstream of the feed directional switching valve 5, and is supplied to the feeding hydraulic motor 1 through the directional switching valve 5, so that the hydraulic motor 1 can rotate forward or backward at high speed. It rotates and moves the bit back and forth within the hole at high speed, allowing flushing work to be performed.

(Operations and Effects of the Invention) The embodiment has been described in detail above, but in the present invention, the pressure oil discharged from the first hydraulic pump 2 passes through the variable flow rate control valve 4 and the directional control valve 5 to the hydraulic motor 1. These are connected in series in this order so that the pressure oil discharged from the second hydraulic pump 3 is connected between the variable flow rate control valve 4 and the directional control valve 5 to the directional control valve 6 for speed switching. Since the speed switching valve 6 is connected to the low speed position 6a and the variable flow rate control valve 4 is operated, the speed of the hydraulic motor 1 can be finely adjusted at low speed. Even if the load of 1 changes, the speed will not suddenly change. By switching the speed switching valve 6 to the high speed position 6b, the hydraulic motor 1 can be operated at high speed.

Although the above embodiment describes an example in which the present invention is applied to drive a hydraulic motor for moving the bit of a crawler drill up and down, the present invention can be widely applied to drive other hydraulic motors. .

[Brief explanation of the drawing]

1 to 3 are circuit diagrams showing one embodiment of the present invention in different operating situations, and FIG. 4 is a schematic side view of a crawler drill. 2...First hydraulic pump, 4...Variable flow control valve, 5...Directional switching valve, 1...Hydraulic motor, 3...
...Second hydraulic pump, 6...Directional switching valve for speed switching.

Claims (1)

[Scope of utility model registration request] These are connected in series in this order so that the pressure oil discharged from the first hydraulic pump is supplied to the hydraulic motor via the variable flow control valve and the directional control valve, and the variable flow control valve and the directional control valve are connected in series in this order. A hydraulic drive device characterized in that the pressure oil discharged from the second hydraulic pump is connected so that it can merge through a directional switching valve for speed switching.