JPH0344472Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a lifting/lowering balance device for a work head used in an industrial robot or the like.

(Prior Art) Recently, a wide variety of industrial robots have been introduced into various production fields.

However, all of these robots are generally equipped with a spatially movable work head for performing the desired work, such as welding, machining, or gripping. In order to increase the operating efficiency of these robots equipped with a work head that moves spatially, the work head must operate as fast as possible, stop accurately at the set teaching position, and be positioned with high precision. It is essential that

However, the weight of the above-mentioned work head may be quite large depending on the type of work member to be assembled to the work head, due to the need to ensure the holding strength and stability of the holding state. This requires that the capacity of the drive means (usually hydraulic or pneumatic cylinders are used) of the working head itself be considerably increased. In addition, even in such a case, especially when the work head moves up and down in the vertical direction, the load applied to the drive means differs when descending and when ascending, and when descending, there is a rather negative load in the operating direction. On the other hand, a large operating force is required when ascending, making it impossible to perform stable operating control.

Therefore, conventionally, the work head is slidably installed on a guide stand extending in the vertical direction, and a guide roller is provided at the upper end of the guide stand. a hydraulically actuated balance cylinder is provided at a distance of 100 m, and the work head is suspended from the balance cylinder by wire means via the guide roller, so that the work head is substantially free of its own weight; A configuration has been adopted that eliminates the load amount restriction on the work head drive control described above (see, for example, Japanese Utility Model Application No. 61-78598).

(Problem to be Solved by the Invention) However, in the configuration of the prior art described above, since the distance between the work head guide surface and the balance cylinder is determined only by the diameter of the guide roller, it is difficult to install the lifting cylinder. In order to achieve this, it is necessary to considerably increase the diameter of the guide roller.

Furthermore, since the lifting cylinder is installed in a narrow space between the working head guide surface and the balance cylinder, there is a problem that the maintenance workability of the lifting cylinder becomes extremely poor.
In particular, the wire means for suspending the working head is located at the front of the lifting cylinder, making maintenance work from the front side difficult.

(Means for Solving the Problems) The present invention was made for the purpose of solving the above problems, and includes an elevating cylinder, a work head that is driven by the elevating cylinder to move up and down, and a work head that In a lifting balance device for a work head, which comprises a guide stand that guides the work head in the vertical direction, and a balance cylinder that is connected to the work head and reduces the lifting load of the work head, the front side of the guide stand is aligned vertically in the up-down direction. on the face,
The other rear side is formed with a vertically inclined surface corresponding to the vertically vertical surface, the guide portion of the work head is formed on the vertically vertical surface of the front side, and the balance cylinder installation portion is formed on the rear side inclined surface. At least two balance cylinders are installed at both left and right ends of the rear inclined surface, and each of the two balance cylinders is connected to the The lifting cylinder is connected to both left and right ends of the work head and installed in a space between the vertical vertical surface on the front side and the inclined surface on the rear side behind the central position of the guide part.

(Function) According to the above means, firstly, by making the rear side of the guide stand an inclined surface, the overall shape of the guide stand becomes approximately trapezoidal, so that it can perform a stable support function, and the front side and rear side Sufficient installation space for the lifting cylinder can be provided between the side and the side.

Two balance cylinders are installed on both sides of the rear inclined surface, and these balance cylinders are connected to both left and right ends of the work head on the front side of the guide table by flexible connecting means. Since the elevating cylinder is located in the middle between the two, the front surface of the elevating cylinder is open, and maintenance work on the elevating cylinder is facilitated.

(Embodiment) FIGS. 1 to 4 show a work head lifting/lowering balance device according to an embodiment of the present invention.

First, Figure 1 shows the overall configuration of the device.
Reference numeral 1 in the drawing designates a work head to which a spot gun 2 is attached for spot welding panel members such as automobile doors. This work head 1 is
A head stand 1A, which is the main body of the work head, and a guide stand 3, which supports the head stand 1A and will be described later on the bottom side.
It is composed of a base plate (receiver) 1B that engages with a guide portion 4 formed on a vertical vertical surface 3A on the front side, and the spot gun 2 mentioned above is mounted at the tip of the head stand 1A in the vertical direction as shown in the figure. Fixed.

The guide stand 3 is constituted by a trapezoidal frame member having a vertical surface 3A extending in the vertical direction on its front side and a vertically inclined surface 3B corresponding to the front vertical surface 3A on its rear side. As mentioned above, the guide part 4 for raising and lowering the working head is provided on the front vertical surface 3A, and the rear inclined surface 3
Installation parts 6A and 6B for balance cylinders 5a and 5b are formed on both sides of B, respectively. Note that the guide stand 3 is supported on an X-axis table 30X, and the X-axis table 30X is supported on a Y-axis table 30.
It is supported on Y.

And the balance cylinder installation parts 6A, 6
B includes a pair of left and right balance cylinders 5a,
5b is installed. This balance cylinder 5
For example, as shown in FIG. 2, a and 5b are constituted by pneumatic cylinders (details will be described later), and the rear end of the cylinder tube 8 is connected to the balance cylinder installation part 6A via a mounting bracket 9. , 6B, and is pivotally attached to a bracket 10 provided on the brackets 10 and 6B so as to be rotatable in the vertical direction. A rack-type belt chuck 12 is fixed to the tip of the actuating rod 11 of the balance cylinders 5a, 5b.
A long clamping plate 15 that engages with an engagement groove 13a of a rotation prevention member 13 fixedly provided on the front end side of the cylinder tube 8 is attached to the bolts 16,1.
6, and a timing belt (corresponding to the flexible coupling means in the scope of the utility model registration claim) is attached to the rack groove 12a.
By engaging and fixing one end of the timing belt 17, the timing belt 17 can be connected to the cylinder actuating rod 11 without twisting. Moreover, in this case, the clamping plate 15 for connecting the timing belt also serves the function of preventing twisting of the timing belt 17, so that the structure can be simple.

The timing belt 17 is connected to two pairs of guide pulleys 20, 2 which are pivotally supported at both front and rear ends of the top of the guide table.
0 to the base plate 1 of the working head 1
B is connected to both sides of the upper end.

Further, reference numeral 35 is an elevating cylinder for elevating the work head 1, and is installed between the rear inclined surface 3B and the front vertical surface 3A of the guide table 3, and the tip of the operating rod 35a is used to raise and lower the work head 1. It is pivotally connected to the center of the back side of the base plate 1B of the head 1.

On the other hand, the balance cylinders 5a and 5b each have a relief regulator 3 as shown in FIG.
0, and a pressure gauge 32 is provided between the balance cylinders 5a, 5b and the relief regulator 30. Therefore, first, when the work head 1 is raised, compressed air from the air pump 31 is supplied into the cylinder through the relief regulator 30 to forcibly lower the actuating rod 11 and raise the work head. Try to lift 1. On the other hand, when the work head 1 is lowered, the pressing force of the lifting cylinder 35 acts on the work head 1, so that the air pressure in the cylinder tube 8 rises to a predetermined value or more. As a result, the pressure gauge 32 operates and the relief regulator 30
By gradually relieving the compressed air in the cylinder tube 8, the actuating rod 11
is raised to suspend the work head 1. As a result, the working head 1 is driven by the lifting cylinder 35 in a balanced state with almost no load.

According to the above configuration, firstly, by making the rear side of the guide stand 3 the inclined surface 3B, the guide stand 3
The overall shape becomes approximately trapezoidal as shown in FIG. 4, which enables it to perform a stable support function, as well as the front vertical surface 3A and the rear inclined surface 3B.
A sufficient installation space A for the elevating cylinder 35 can be provided between the two.

Two balance cylinders 5a, 5b are installed on both sides of the rear inclined surface 3B, and these balance cylinders 5a, 5b are connected to the front surface of the guide stand 3 by flexible timing belts 17, 17. It is connected to both the left and right ends of the side work head 1, and an elevating cylinder 3 is located in the middle between them.
5, the front surface of the lifting cylinder 35 is opened as shown in FIG. 5, making maintenance work for the lifting cylinder 35 much easier.

(Effects of the invention) As explained above, the present invention includes an elevating cylinder, a working head that is driven by the elevating cylinder to move up and down, a guide table that guides the working head in the vertical direction, and A lifting balance device for a work head comprising a balance cylinder coupled to a balance cylinder for reducing the lifting load of the work head, wherein the front side of the guide stand is aligned with a vertical plane in the vertical direction, and the rear side of the guide stand is aligned with the vertical plane in the vertical direction. A guide portion for the work head is formed on the vertical vertical surface on the front side, and a balance cylinder installation portion is formed on the sloped surface on the rear side. At least two balance cylinders are installed at both left and right ends of the rear inclined surface, and these two balance cylinders are connected to both left and right ends of the work head through guideable flexible connecting means, respectively. It is characterized in that the elevating cylinder is installed in a space between the vertical vertical surface on the front side and the inclined surface on the rear side behind the center position of the guide part.

Therefore, according to the present invention, first, by making the rear side of the guide stand an inclined surface, the overall shape of the guide stand becomes approximately trapezoidal, which enables it to perform a stable support function, and also allows the front side and rear side to be sloped. Sufficient installation space for the lifting cylinder can be provided between the

Two balance cylinders are installed on both sides of the rear inclined surface, and these balance cylinders are connected to both left and right ends of the work head on the front side of the guide table by flexible connecting means. Since the elevating cylinder is located in the middle between the two, the front surface of the elevating cylinder is open, making maintenance work for the elevating cylinder easier.

[Brief explanation of the drawing]

Fig. 1 is a perspective view of a work head lifting/lowering balance device according to an embodiment of the present invention, Fig. 2 is a perspective view of a balance cylinder portion of the device, and Fig. 3 is an air pressure of the balance cylinder portion of the device. Control circuit diagram, 4th
The figure is a side view for explaining the structural features of the device, and FIG. 5 is a front view of the same. 1... Working head, 2... Spot gun, 3...
...Guide stand, 3A...Front side vertical surface, 3B...Rear side inclined surface, 4...Guide part, 5a, 5b...Balance cylinder, 6A, 6B...Balance cylinder installation part, 7...Timing belt, 35... Lifting cylinder.

Claims (1)

[Scope of utility model registration request] A lifting cylinder, a working head that is driven by the lifting cylinder to move up and down, a guide table that guides the working head in the vertical direction, and a balance cylinder that is connected to the working head and reduces the lifting load of the working head. In the lifting balance device for a work head, the front side of the guide stand is formed into a vertical vertical surface, and the other rear side is formed into a vertical inclined surface corresponding to the vertical vertical surface, and the front side is formed into a vertical inclined surface corresponding to the vertical vertical surface. A guide portion for the work head is formed on the vertical surface, and a balance cylinder installation portion is formed on the rear inclined surface, and at least two balance cylinders are installed at both left and right ends of the rear inclined surface. These two balance cylinders are connected to both left and right ends of the work head through guideable flexible connecting means, respectively, and are connected to the vertical vertical surface on the front side behind the central position of the guide part and the above. An elevating and lowering balance device for a work head, characterized in that the elevating cylinder is installed in a space between the work head and the rear inclined surface.