JPS5834210A - Drive controller for hydraulic actuator - Google Patents

Abstract

PURPOSE:To reduce working time when a drive controller is applied for robots or the like, by simultaneously driving hydraulic actuators each of which can be operated in at least two directions by means of a master cylinder which follows at least two cams driven by a same shaft. CONSTITUTION:A master cylinder 69 is connected through lines 85b and 86b to oil chambers 33 and 34 which are divided by a piston 35 of a hydraulic actuator 30. A pinion 38 engaged with a rack 39 which is integrated with a rack actuating shaft 39 of a rack actuator 40 is attached to one end of an actuating shaft 32 which is integrated with the piston 35, while a working arm 48 provided a chuck 49 at the tip thereof is firmly attached to the other end. A master cylinder 68 is connected to the rack actuator 40 through lines 85A and 86A while another master cylinder 70 is connected to a chuck actuator 50 inside the working arm 48 through lines 85c and 86c. Operation of the master cylinders 68 through 70 are controlled by grooved cams 61 through 63 via levers 65 through 67, respectively.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a drive device for a hydraulic actuator used in a work robot or the like.

It is well known that work robots have recently been widely introduced to manufacturing sites.

These work robots perform complex tasks such as extending their arms to grasp, lift, move, and lower workpieces, and these tasks are primarily performed using hydraulic actuators. A typical example will now be explained with reference to FIGS. 1 and 2.

In FIG. 1, reference numeral 1 has a working member (not shown) at the left end and is supported by both ends of the actuator body 2 so that it can slide and rotate freely, and 3 and 4 are housed in the cylinder 5 of the actuator, respectively. They are a rotating piston and a forward piston.

This straight-moving piston 4 is fixed to the operating shaft 1, and its left end is locked to the cylinder 5 by a method not shown in the drawings at the position where the operating shaft 1 is advanced most to the left as shown in FIG. Also,
The rotating piston 3 is locked to the cylinder 5 in the rotational direction by a method not shown, and is slidable in the axial direction.
engaged by.

These pistons 3 and 4 cause the cylinder 5 to have a first
-3 oil chambers 7, 8.9 are defined and communicated with the outside through first to third bows (10, 11, 12), respectively.

In FIG. 2, 13, 14, 15 are first to third air-hydro converters, 16, 17, 18 are first to third three-way solenoid valves, and the air pressure adjustment unit 2 is connected to the air source 19.
The compressed air that has passed through 0 is led to the air chambers of the 3rd to 3rd air-hydro converters 13 to 15, and the hydraulic oil in the oil chambers is transferred to the 1st to 3rd boats 10 to 12, respectively, via the speed controllers 21 to 21. It is designed to be pumped. In addition,
22. 22 is a pulp for adjusting the oil amount of each hydraulic oil.

These three-way solenoid valves 16 to 18 each have an electric control section 2.
3, and its electric control unit 23 controls the first to third electromagnetic circuits by a built-in sequence and a limit switch 25 and K that detect the displacement of the cam 24 attached to the right end of the operating shaft 1 of the hydraulic actuator. Switch valves 16 to 18,
Transfer the compressed air to the first to third air hydro masters 13 to xsK.
It is like this.

With the above structure, for example, when pressure oil is introduced into the first and second boats 10 and 11, the first and second oil chambers 7 and 8 become equal pressure, and therefore the rotating piston 3 is moved to the operating shaft 1. The straight piston 4 is pressed and retreats without relative displacement, and as a result, the operating shaft 1 retreats together with the rotation piston 3. In addition, in order to advance the operating shaft 1 from that position, the second and third boats 11 and 12 are
Just guide the pressure oil to.

On the other hand, when pressure oil is introduced into the first and third bows 10 and 12, the linear piston 4 is pressed by the oil pressure in the third oil chamber 9 and is locked to the cylinder 5, so the operating shaft 1 is Although not displaced in the axial direction, the rotating piston 3 is pressed by the oil chamber of the first oil chamber 7 and retreats. As a result, the straight piston 4
The actuating shaft 1, which is engaged with the actuating shaft 1, is rotated in the direction of the arrow via the involute spline 6 by the rotating piston 3, which moves backward.

In addition, in order to rotate the operating shaft 1 in the opposite direction to the above, the second
Then, pressure oil may be guided to the third boats 11 and 12.

By the way, as described above, in this hydraulic actuator, the forward and backward movement and rotation of the operating shaft 1 are performed independently, and cannot be performed simultaneously. Therefore, in order to shorten the working time, it is necessary to increase the supply speed of hydraulic oil, but this also has its limits and is not satisfactory.

The present invention is intended to solve the above-mentioned problems, and is a hydraulic actuator drive control device that can be used in a work robot to reduce work time by driving the hydraulic actuator in at least two directions at the same time. The purpose is to provide

An example of the present invention will be described below with reference to the drawings.

In FIG. 3, 30 is a hydraulic actuator, 31 is a cylinder body, 32 is an operating shaft, and 33 and 34 are operating shafts 3.
First and second oil chambers are defined by a piston 35 fixed to 2 and communicated with the outside by first and second boats 36 and 37, respectively.

A pinion 38 is attached to one end of the operating shaft 32, and a rack 39 that engages with the pinion 38 is coupled to a rack operating shaft 41 of a rack actuator 40.

42 is housed in the rack cylinder 43 and is connected to the rack operating shaft 41.
The rack pistons 44 and 45 are fixed to the rack piston 42 and define first and second oil chambers communicated with the outside by first and second boats 46 and 47, The actuating shaft 41 moves forward and backward to rotate the actuating shaft 32 of the hydraulic actuator 30 in forward and reverse directions.

On the other hand, a working arm 48 is fixed to the other end of the operating shaft 32, and a chuck 49 is provided at the tip thereof. 50
is a chuck actuator formed on the work arm 48, 51 is a chuck piston housed in its chuck cylinder 52, and 53 and 54 are chuck pistons 51.
a first and a second boat 55 and 5;
first and second oil chambers, 57 communicating with the outside via 6;
is a chuck operating shaft, one end of which is fixed to the chuck piston 51, and the other end connected to the chuck 49. As the chuck piston 51 moves back and forth, the chuck 49 is moved.
It is K-shaped so that it can be opened and closed.

These hydraulic actuators 30, 40, 50 will be explained with reference to FIG. 4 as well. 6o is the device main body, 61°62.63
First to third grooved cams 65 fixed to the drive shaft 64
, 64 and 67 are engaged with the grooved cams 61 to 63, respectively, and one end is pivotally supported by the device main body 6o and is swingable.
The levers 68, 69 and 70 are the first to third mask cylinders, and their master operating shafts 71A, 71B, 71C
One end is connected to the first to third levers 65, 66, and 67, respectively.
The first to third L grooves 65A, 66A, and 67A formed in the grooves 65A, 66A, and 67A engage with the rotation of the grooved cams 61 to 63 to swing.
/ bars 55 to 67 to move back and forth in the axial direction.

These mask cylinders 68 to 7o are housed in cylinders 72A, 72B, and 72C, respectively, and are connected to the master operating shaft 7.
Mask piston 73 fixed to 1A, 71B, 71C
A, 73B, and 73C provide the first and second oil chambers 74A.
, 74B, 74C and 75A, 75B, 75C are defined.

Those oil chambers each include a rack actuator 40,
Hydraulic actuator 30. Chuck actuator 50
the first and second boats of 46, 47; 36.37; 5
5, 56, and the mask pistons 73A to 7
By the displacement of 3C, hydraulic oil is discharged and sucked into the corresponding boat, the operating shaft 32 is moved forward and backward via the rack 39, the operating shaft 32 is moved forward and backward via the piston 35, and the chuck is moved via the chuck piston 51. 49 can be opened and closed.

The profiles of the first to third grooved cams 61 to 63 are determined by rotating the working arm 48 forward in the direction of arrow R while moving the operating shaft 32 forward in the direction of arrow F from the original position shown in FIG. 3, for example.
Once stopped, the chuck 49 is closed and a workpiece (not shown) at a predetermined position is pulled, and then the operating shaft 32 is moved back in the direction of arrow R, the chuck 49 is opened and the workpiece is placed in a predetermined position, and then the work arm 48 in the direction indicated by the arrow to remove the chuck 49 from the workpiece, the work shaft 32
When the working arm is moved backward in the direction of arrow R and the working arm is reversely rotated in the direction of arrow R to return to the original position, one cycle can be performed continuously.

The device is equipped with means by which the stroke and initial position of the mask cylinders 68-70 can be adjusted. This means includes a bracket 76 that swingably supports one end of the mask cylinders 68 to 70 on the apparatus main body 60, and a long groove 65A of the lever 65, 66, 67 that receives the other end.
, 66A.

67A and more.

The bracket 76 is attached to a long hole 77 formed in the device body 60 with a bolt 78, and its position in the vertical direction can be adjusted by a bolt 79 inserted through the earthen wall.

Furthermore, this device is equipped with a hydraulic oil replenisher 80 that can replenish leaked hydraulic oil and adjust the initial position of each actuator 40, 30 and 50.

This hydraulic oil replenisher 80 will be explained with reference to FIG. In the figure, 81 is the supply device main body, 82 is the pressurizing passage, 83A,
83B, 83C and 84A.

84B and 84C are provided in pairs in a direction perpendicular to the pressure passage 82, respectively, and are connected to the first to third mask cylinders 68 to 7 (l) each actuator 40, 30.
．． Pipe lines 85A, 85B, 85C and B6A, 86B communicating with 50.

86C, which connects the pressurizing passage 82 to the communicating passages 87A, 87B, 87C and 88A, 88B.
, 88C, and is normally closed by a ball 91 pressed against a bolt 90 of the ball valve 89.

Note that a constant hydraulic pressure from a hydroconverter 92 is guided to the pressurizing passage 82 .

In this hydraulic oil replenisher 80, when the bolt 90 is loosened, the ball 91 is pressed by the hydraulic pressure in the pressurizing passage 82 to open the valve, and the actuator 40 , 30.50, the hydraulic pressure of the hydro converter 92 is led to the corresponding oil chambers.

Next, the effect will be explained.

, the first to third grooved cams 61 to 63 simultaneously rotate at a constant speed from their initial positions. Therefore, the engaged first to third levers 65 to 67 are guided by the profile and swing, causing the mask actuation shafts 71 to 71C to move forward and backward. As a result, the first to third mask cylinders 68 to 70
performs discharge and suction of hydraulic oil to each actuator 40, 30 and 50, and moves each piston 42, 35 and 51 forward and backward. As a result, the forward and reverse rotation of the operating shaft 32, the forward and backward movement, and the opening and closing of the chuck 49 are controlled by the cams 61 to 61.
This is done simultaneously or arbitrarily in accordance with the profile of the cams 61 to 63, and the cams 61 to 63 return to their original positions by one rotation.

As a result, the working time is significantly reduced by about 50% compared to the conventional apparatus in which each work operation is performed independently.

For example, if the stroke or capacity of the hydraulic actuator changes, the following steps will be taken.

That is, the second mask cylinder 69 is rotated clockwise in FIG.
The position where the lever 66 engages with the long groove 66A is moved outward. As a result, the profile of the second grooved cam 62 is expanded in accordance with the amount of movement, and the stroke of the mask actuating shaft 71B is increased. As a result, the amount of hydraulic fluid discharged from the second mask cylinder 69 to the hydraulic actuator 30 is increased. is increased, and can accommodate an increase in the stroke or capacity of the hydraulic actuator 30.

Furthermore, if the hydraulic oil in the second mask cylinder 69 and the hydraulic actuator 30 leaks over time and the initial position of the hydraulic actuator 30 shifts, the hydraulic oil replenisher 8
0 to adjust the initial position.

That is, the operating shafts 32 and 71B are fixed at their initial positions, and the ball valve 89 on the passage 84B side of the hydraulic oil replenisher 80 is first opened.
The ball valve 89 is opened, and the pressure oil of the hydraulic converter 92 is guided and filled into the respective first oil chambers 33 and 74B via the pressurizing passage 82, the communication passage 88B1 passage 84B, and the pipe 86B, and the ball valve 89 is opened. close. Then, the second oil chambers 34 and 75B are filled in the same manner. lastly,
By releasing the fixation of the operating shafts 32 and 71H, the hydraulic cylinder 30 can be reliably adjusted to the initial position.

FIG. 6 shows another embodiment of the present invention, which differs from FIG. 3 in that the hydraulic actuator 30 is of the same type as in FIG. 1, and the first and second mask cylinders 6B and 69 are The connections of the pipes are as shown in the figure.

According to this embodiment, there are the same effects as in the third section.

As explained above, according to the present invention, a hydraulic actuator capable of operating in at least two directions can be simultaneously operated by a mask cylinder driven by at least two cams driven on the same axis. Therefore, the use of hydraulic actuators in working robots has the effect of greatly shortening the working time.

Furthermore, the adjustment device allows for easy adaptation to changes in the capacity and stroke of the hydraulic actuator.

Furthermore, since oil leakage from the hydraulic cylinder can be compensated for periodically, good control accuracy can always be obtained.

[Brief explanation of the drawing]

Fig. 1 and Fig. 2 show a conventional device, Fig. 1 is a sectional view of a hydraulic actuator, Fig. 2 is a schematic diagram of the overall configuration, and Figs. 3 to 5 show an embodiment of the present invention. So, the third
(5) is a schematic diagram of the overall configuration, FIG. 4(a) is a front view of the device, FIG. 4(b) is a side view, and FIG. 5(a) is a side view of the hydraulic oil supply device. FIG. 6(b) is a sectional view taken along the line A-A, and FIG. 6 is a schematic diagram of the entire structure showing another embodiment of the present invention. DESCRIPTION OF SYMBOLS 1... Operating shaft, 3... Piston for rotation, 4... Piston for linear movement, 30... Hydraulic actuator, 32...
... Operating shaft, 3-5... Piston, 38... Pinion, 39... Rack, 40... Rack actuator, 41... Rack operating shaft, 42... Rack piston, 48... - Work unit, 51... Chuck piston, 57... Chuck operating shaft, 6o... Device main body, 61-63... First to third grooved cams, 64... Main drive shaft, 65- 67...1st to 3rd levers, 68 to 7o.
... 1st to 3rd mask cylinders, 71... Master operating shaft, 73... Mask piston, 76... Placket, 8o... Hydraulic oil supply device, 82... Pressurizing passage, 8
9... Hall valve, 92... Hydro converter patent applicant Hiroshi Okumura Figure 4 (b) Figure 5 (a) "A Figure 5 (b)

Claims (1)

[Scope of Claims] 1. A drive device for a hydraulic actuator that can operate in at least two directions, including at least two cams attached to the same drive shaft, and each cam being driven to act on the hydraulic actuator. A hydraulic cylinder drive control device comprising a mask cylinder that discharges and sucks oil. 2. In a hydraulic actuator drive device that can operate in at least two directions, at least two cams are attached to the same drive shaft, and each cam is driven to discharge and suck hydraulic fluid to the hydraulic actuator. What is claimed is: 1. A drive control device for a hydraulic actuator, comprising: a mask cylinder for controlling the mask cylinder; and means for adjusting the stroke and initial position of the mask cylinder. 3. A hydraulic actuator capable of operating in at least two directions;
In the evening drive system, there are at least two cams attached to the same drive shaft, a mask cylinder that is driven by each cam to discharge and suck hydraulic fluid to the hydraulic actuator, and a mask cylinder that discharges and sucks hydraulic fluid to the hydraulic actuator, and a mask cylinder that discharges and sucks hydraulic fluid to the hydraulic actuator. A drive control device for a hydraulic actuator, comprising means for replenishing the actuator and adjusting an initial position of the actuator.