JP2745217B2 - Automatic tool changer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic tool changer, and more particularly, to a first unit connected to operating means such as a robot and at least one second unit to which various tools can be attached. The present invention relates to an automatic tool changer provided so as to connect one second unit to a first unit in a separable manner.

[0002]

2. Description of the Related Art A coupling device for both units provided in an automatic tool changer having the above-mentioned construction is generally constituted by two rod-like levers provided on a robot side unit so as to be able to swing, and a piston rod on both levers. It consists of a combined air cylinder and two connecting pins provided on the tool-side unit. When connecting both units, the air cylinder is operated while the contact surfaces of both units are in contact with each other, and both levers are synchronously swung to lock and lock the connecting pins. The supply of air pressure for operating the air cylinder is performed through a flow path (line) including a joint attached to a side surface of the robot side unit and a pipe provided inside the unit.

The conventional automatic tool changer supplies a control electric signal line for transmitting an electric signal for controlling the tool to a tool attached to the tool side unit, and an air pressure or a hydraulic pressure for operating the tool. An air / hydraulic line for operation or a cooling water line for cooling the tool is provided.

The control electric signal line is composed of an electric conduit provided on a side surface of each unit, an electric contact or an electric connector provided on a contact surface of each unit, and a lead wire for connecting these inside each unit. You. Further, the operating air pressure / hydraulic line and the cooling water line are composed of joints provided on the side and contact surfaces of each unit, and pipes or flow paths connecting these in each unit. Electric signals, air pressure, hydraulic pressure, etc. sent from the robot enter both units through the electric conduits and joints on the side of the robot side unit, and exit from the electric conduits and joints on the side of the tool side unit and are sent to the tool. is there.

[0005]

In the conventional automatic tool changer, an electric conduit for a control electric signal line,
Since the electrical connectors and the joints of the air pressure / hydraulic line for operation and the cooling water line are fixedly provided on each unit main body, if the conditions required for tool control and operation are significantly different, they can no longer be operated with the same device. And had to be operated by another automatic tool changer.

That is, for example, when a hydraulic gripper is mounted as a tool, a hydraulic line for supplying an operating hydraulic pressure and a small-capacity electric signal line for transmitting an electric signal for control of about several A are required. When a spot welding gun is installed, a welding current line having a current capacity of about 100 A and a cooling water line are required in addition to the small-capacity electric signal line for control. Like both of these,
If the conditions required by the tools to be operated differ greatly, it is no longer possible to use the same device and it is necessary to provide a number of automatic tool changers.

Therefore, according to the present invention, an electric signal line and a current line necessary for controlling and operating the attached tool,
Alternatively, even if the lines of air pressure, hydraulic pressure, water, etc. are significantly different, an automatic tool changer that can select and provide the optimal line according to each tool, in other words, freely connect the joint of the desired line It is an object of the present invention to provide an automatic tool changer that can be changed and that can improve the working efficiency at low equipment cost.

[0008]

According to the present invention, there is provided a first unit or the tool attached to the operation unit for supplying electricity, gas, air, water, etc. from the operation unit side of the robot to the tool side. One of the second units is provided with a male joint part and the other is provided with a female joint part. When the first unit and the second unit are properly joined, the male and female joint parts are mutually connected. In the automatic tool changer in the connected state, each of the first and second units can be detachably attached to the main body in which a plurality of attachment portions are arranged on the outer peripheral surface at a distance, and to the attachment portion. And a plurality of types of modules having at least one type of joint among electricity, gas, air, water, and oil, and each module is provided in accordance with a type of tool provided on the second unit side. It is to be able to attach to the mounting portion of the main body portion select.

The present invention is configured as described above and has the following functions. Even if electric signal lines and current lines necessary for control and operation of the installed tools, or lines such as air pressure, hydraulic pressure, and water are greatly different, an optimal line can be selected and provided according to each tool. Since a plurality of types of modules are attached to each of the first and second units, an apparatus having many types of different lines can be easily manufactured by combining a small number of modules. The path of an electric signal line or the like may be restricted by the shape of the tool or the like. In this device, the arrangement of the joints of each line of the unit on the tool side can be freely changed by exchanging the module (for example, the module of the hydraulic line). And the module of the pneumatic line can be replaced), so that the path of the electric signal line and the like can be set according to the shape of the tool and the like.

When it is necessary to change the type, capacity, etc. of electricity, gas, air, water, etc. to be used according to the purpose of use of the tool, only the module having the joint part to be changed is used as the main body. And a module of a desired type and capacity may be mounted.

[0011]

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

FIG. 1 shows an embodiment of an automatic tool changer according to the present invention. In FIG. 7, reference numeral 1 denotes an automatic tool changer, 2 denotes a first unit attached to operation means (not shown) such as a robot arm, and 3 denotes a second unit to which a spot welding gun 4 is attached. A plurality of the second units 3 to which various tools such as the spot welding gun 4 are attached are prepared and arranged on a shelf. At the time of work, any one of the second units 3 is selected, the first unit 2 is combined and integrated, and a predetermined work can be performed by a robot or the like.

The upper first unit 2 comprises a main body 2a and a convex portion 2b. As shown in FIGS. 3 and 5, the main body 2a is formed by cutting out two substantially fan-shaped portions from a flat cylindrical member. And has a substantially Y-shaped shape. Interface modules 5 and 6 are detachably attached to the cutouts of the main body 2a, respectively, so as to be substantially one cylindrical shape as a whole. In addition, the fan-shaped part 7 which is not notched has a side surface,
An electric conduit 8 for sending a control electric signal to a tool attached to the second unit 3 and four air ports 9 for supplying and discharging control air to the tool are provided, and the lower surface is connected to the electric conduit 8. Electrical connector (not shown) and joint (not shown) communicating with air port 9
Is provided. A flange 10 is provided above the notch-side edge of the main body 2a, and the interface modules 5 and 6 are bolted to the flange 10.

With this configuration, the mounting and replacement of the modules 5 and 6 can be performed only by tightening and loosening the bolts.
Very simple. Further, since the modules 5 and 6 are fitted in the cutouts in a shape corresponding to the cutouts of the first unit 2, the modules 5 and 6 are connected to the first unit 2.
Has the advantage that it hardly protrudes outside the cylindrical shape.

The convex portion 2b is formed in a star shape and has a main body 2a.
Protruding from the lower surface of the. The projections 2b are 12
It consists of three parts 11 extending along three radii forming 0 ° and joined together at the center.

The interior of the first unit 2 is notched in a star shape similar to the convex portion 2b at a depth reaching from the upper end surface to the vicinity of the lower end of the convex portion 2b, and extends along each portion 11 of the convex portion 2b. Three cylinder housing chambers 12 are formed. The cylinder housing chamber 12 is a space for housing a cam driving air cylinder to be described later. The upper opening of the cylinder housing chamber 12 has a lid 1 made of a circular plate attached to the upper surface of the main body 2a.
3 is cold.

A window 14 is formed by forming a rectangular hole at the tip end 11a of each portion 11 of the convex portion 2b. As shown in FIG. 15 are provided. The cam 15 is supported by a support pin 16 that extends laterally (horizontally) from the outside to the distal end portion 11 a of the portion 11 and extends in the window 14. Surface) so as to be rotatable within the window 1
It is pivotable between the outside and the inside of the part 11 through 4.

The cam 15 engages with an engagement pin provided on the second unit 3 described later at an arc-shaped edge portion 15a, and the support pin 16 is provided at a position close to the opposite corner 15b. Further, since the distance between the engaging portion 15a of the cam 15 and the rotation shaft, that is, the support pin 16, is set so that the outer portion is minimum and gradually increases inward, the position of the support pin 16 is increased. Are shifted downward from a straight line that bisects the angle between both ends of the arcuate engaging portion 15a.

The three cams 15 are provided with driving air cylinders 17 provided in the three cylinder accommodation chambers 12 described above.
, Respectively. Each of the cylinders 17 is supported by a mount 19 fixed to both inner surfaces of the portion 11 via a support member 18, and is rotatable up and down along the central axis of the first unit 2. Air cylinder for driving 1
Supply and discharge of air to and from the connection pipes 22 and 2 are performed by air ports 20 and 21 provided on the side surface of the main body 2a.
3 is performed.

Each of the air cylinders 17 is arranged such that a piston rod 24 is parallel to the cam 15. A U-shaped joint 25 is fixed to the tip of the piston rod 24 with its two legs facing the cam 15 side, and the cam 15 is sandwiched between the two legs of the joint 25. In this manner, it is rotatably connected to the cam 15. The connection between the joint 25 and the cam 15 is performed by a connection pin 26 provided therethrough. The connection pin 26 penetrates the cam 15 at a position near the engagement portion 15b.

With the above configuration, the driving air cylinder 1
When the piston 7 is actuated and the piston rod 24 is moved in and out, the movement is transmitted to the cam 15 by the U-shaped joint 25 and the connecting pin 26, so that the cylinder 17 rotates the cam 15 around the support pin 16. Can be.

The interface module 5
Supplies an electric current for welding to the welding gun 4, and has an electric conduit 27 on a side surface and electric contacts 28a and 28b on a lower surface. Other module 6
Supplies cooling water to the welding gun 4, and has a water port 29 on the side surface and two connection holes 30 on the lower surface.

Reference numeral 31 denotes a positioning pin provided on the lower surface of the main body 2a. The second unit 3 includes the first unit
It has a substantially Y-shaped shape similar to that of the unit 2. Interface modules 32 and 33 are detachably attached to the two portions, each of which is cut out in a substantially fan shape, so as to form one column substantially identical to the first unit 2 as a whole. These modules 3
The units 2 and 33 are paired with the modules 5 and 6 attached to the first unit 2 so that the units 2 and 3 overlap each other when the units 2 and 3 are stacked.

The module 32 for supplying the welding current includes:
An electric conduit 34 is provided on the side surface, and an electric contact 35a and three electric contacts 35b for supplying a standard current are provided on the upper surface. Further, the module 33 for supplying the cooling water includes:
Two water ports 36 on the side and two joints 37 on the top
Are provided respectively. Electrical contacts 35 of module 32
a and the electrical contacts 35b are connected to the module 5 of the first unit 2.
Are located at positions corresponding to the electrical contacts 28a and 28b, respectively, and are connected when the modules 32 and 5 overlap. The two joints 37 of the module 33 are also provided at positions corresponding to the two connection holes 30 of the module 6 of the first unit 2 so as to communicate when the modules 33 and 6 overlap.

Both the modules 32 and 33 are bolted to a flange 38 provided below the notch-side edge, similarly to the modules 5 and 6 of the first unit 2. Therefore, the mounting and replacement of the modules 32 and 33 are very simple, and the advantage that the modules 32 and 33 do not protrude from the second unit 3 is the same as that of the first unit 2.

The fan-shaped portion 39 of the second unit 3 is connected to an electric connector and a joint (not shown) of the first unit 2 when the two units 2 and 3 are overlapped.
An electrical connector 40 and four air joints 41 are provided. The electric connector 40 and the joint 41 are connected to an electric conduit 42 and four air ports 43 provided on the side surface of the sector 39, respectively.

The center of the second unit 3 is cut out in a Y-shape to form a space 44 opened vertically. The Y-shaped convex portion 2b of the first unit 2 is fitted into the space 44. At each of the three outer ends of the space 44, there is formed a dent 45 which is depressed radially outward.
An engagement pin 46 is provided to extend from the outside of the second unit 3 in the horizontal direction. As shown in FIG. 6, the engagement pin 46 is provided at a position near the upper end of the second unit 3, and is orthogonal to a plane including the central axis of the second unit 3. When the two units 2 and 3 are overlapped, the outer surface of the distal end 11a of the convex portion 2b of the first unit 2 is in contact with the inner wall surface 47 of each outer end of the space 44, and the outer end of the cam 15 is in contact with the depression 45. Is inserted. The lower opening of the space 44 is cooled by a lid 48 made of a circular plate attached to the lower end of the second unit 3. The spot welding gun 4 is attached via the lid 48.

Reference numeral 49 denotes a positioning hole into which the positioning pin 31 of the first unit 2 in FIG.
Reference numeral 1 denotes a joint connected to the first unit 2 air ports 20 and 21.

Next, the use state of the automatic tool changer 1 configured as described above will be described.

Here, from among a plurality of second units 3 arranged on a rack by attaching various tools, FIG.
In the second example, the spot welding gun 4 shown in FIG.
Consider the case where unit 3 is selected.

First, the first unit 2 attached to the robot arm is moved above the second unit 3,
The two positioning pins 31 of the unit 2 are connected to the second unit 3
And stops after being aligned with the two positioning holes 49.

Subsequently, the first unit 2 is lowered and the positioning pins 31 are inserted into the positioning holes 49 of the second unit 3 so that the two units 2 and 3 are overlapped. 2 b fits into the space 44 of the second unit 3. At this time, each air cylinder 1 for driving the cam 15
7, air is supplied in the direction in which the piston rod 24 is retracted. As shown in FIG. 1, most of the cam 15 is retracted inside the cylinder accommodating chamber 12, so that the two units 2 and 3 are fitted. If there is no problem.

When the lower end surface of the main body 2a of the first unit 2 and the upper end surface of the second unit 3 come into complete contact, automatically,
The electric connector and the air joint (not shown) provided on the sector 7 of the first unit 2 are connected to the sector 39 of the second unit 3.
Are connected to the electric connector 40 and the air joint 41 provided at the same time. Also, the modules 5 and 6 of the first unit 2
Electrical contact 28a, 28b and air connection hole 30
Electrical contacts 35 of modules 32 and 33 of second unit 3
a, 35b and the air joint 37, respectively.

Thus, the control electric signal, the air signal, the welding current and the cooling water sent from the robot to the first unit 2 can be transmitted to the spot welding gun 4 via the second unit 3. It becomes possible.

When the two units 2 and 3 come into contact with each other as described above, the operating valve (not shown) is operated to supply air to each air cylinder 17 in the opposite direction to that of the air cylinder 17 and to cause each piston rod 24 Are projected synchronously. Then, the three cams 15 connected to the respective piston rods 24 rotate outward around the support pins 16, and as shown in FIG. The third engaging pin 46 contacts.

As described above, the engaging portion 15a of the cam 15
The distance between the support pin 16 and the support pin 16 is minimum at a position close to the engagement pin 46 and gradually increases as the distance from the engagement pin 46 increases, so that the engagement pin 46 is pressed as the rotation angle increases. Power increases. Thus, the connection between the units 2 and 3 can be locked and held.

In this embodiment, the relationship between the relative positions of the engagement pin 46 and the support pin 16 and the dimensions of the cam 15 when the two units 2 and 3 are connected is set appropriately, and the engagement portion 15a of the cam 15 is engaged. Since the position where the mating pin 46 is pressed and stopped is set inside the center position where the bisector of the center angle of the cam 15 intersects with the engagement portion 15a, the units 2 and 3 are separated. When a force acts in the direction, most of the moment due to the force acts in a direction in which the cam 15 rotates outward. Therefore, the force acts in a direction to increase the locking force of the two units 2 and 3, and there is an advantage that it is very difficult to separate in such a case.

In consideration of the case where the supply of air is stopped due to an accident such as a power failure, a spring is built in the cylinder 17 so that the piston rod 24 is kept protruding even if the air is exhausted during the supply. It is preferable to configure so that

When the two units 2 and 3 are separated from each other, air may be supplied to the cylinder 17 in the opposite direction. In this case, the cam 15 rotates in the opposite direction and separates from the engagement pin 46, so that the cam 15 can be easily separated.

In the above embodiment, the cam 15 is formed from a substantially fan-shaped plate. However, the present invention is not limited to this, and the cam 15 can be implemented in various shapes such as a disk shape and a cylindrical shape. Of course you can. Also, the engagement portion 15a is not limited to the convex shape. In short, the engagement portion of the cam includes a portion whose distance from the rotation axis is equal to the distance between the engagement pin and the rotation axis of the cam at the time of connection, and a portion larger than the distance.
It is sufficient if the distance changes gradually.

[0041]

The present invention has the above-described configuration and has the following effects.

From the contents described in the section of the means for solving the problems, it was possible to provide an automatic tool changer capable of improving work efficiency at a low equipment cost.

[Brief description of the drawings]

FIG. 1 shows an embodiment of an automatic tool changer according to the present invention, in which a convex portion of a first unit is fitted into a concave portion of a second unit, and a state immediately before the two units are coupled by a coupling device. FIG.

FIG. 2 is a partial cross-sectional explanatory view showing a state where both units are coupled and locked by the coupling device.

FIG. 3 is a plan view of a first unit using the coupling device.

FIG. 4 is a partial cross-sectional explanatory view along the line AA in FIG. 3;

FIG. 5 is a plan view of a second unit using the same coupling device.

FIG. 6 is a partial cross-sectional explanatory view along the line BB in FIG. 5;

FIG. 7 is a perspective view showing an automatic tool changer using the two units shown in FIGS. 3 to 6, with each unit being separated from each other.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Automatic tool changer 2 1st unit 2a Main part 2b Convex part 3 2nd unit 4 Spot welding gun 5 Interface module 6 Interface module 7 Fan-shaped part 8 Electric conduit 9 Air port 10 Flange section 20 Air port 21 Air Port 22 Connecting pipe 23 Connecting pipe 27 Electrical conduit 28a Electrical contact 28b Electrical contact 29 Water port 30 Connection hole 31 Positioning pin 32 Interface module 33 Interface module 34 Electrical conduit 35a Electrical contact 35b Electrical contact 36 Water port 37 Water joint 38 Flange 39 Sector 40 Electric connector 41 Air joint 42 Electric conduit 43 Air port 49 Positioning hole 50 Air joint 51 Air joint

 ──────────────────────────────────────────────────続 き Continued on front page (72) Inventor Bruce Dee. Newell United States 12309 New York Schenectady Trottingham Road 778 (72) Inventor Thomas Jay. Petronis United States 12065 New York Clifton Park Southbury Road 63 (56) References JP-A-59-117077 (JP, A) Jiko 58-17752 (JP, Y2)

Claims (1)

(57) [Claims] An electric power is supplied from the operation unit side of the robot to the tool side.
In order to supply gas, air, water, etc., one of the first unit or the second unit having the tool attached to the operation unit has a male-side joint portion and the other has a female-side joint portion. When the first and second units are properly joined to each other, the male and female joints are connected to each other in an automatic tool changer. A plurality of types including a main body portion in which an attachment portion is arranged at a distance, and a joint portion that can be detachably attached to the attachment portion and that has at least one type of joint among electricity, gas, air, water, and oil. And a module that can be selected according to the type of tool provided on the second unit side and can be mounted on the mounting portion of the main body. Dynamic tool changer.