JP2000301405A - Balancing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To cancel twist acting on a horizontal shaft of machine tool and a table device. SOLUTION: Since a machining table is attached to a horizontal shaft 21, weight of the machining table becomes twist moment and acts on the horizontal shaft 21. A cylinder unit 25 is driven, this driving force is given to the horizontal shaft 21 as twist force and force in the opposite direction through a crank, a shaft 30, a gear 32, a timing belt 34, and a gear 33. Consequently, the twist generated by supporting the machining table on the horizontal shaft 21 eccentrically is cancelled to maintain balance.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a balance device for canceling a torsional force acting on a horizontal shaft of a machine tool, a table device or the like.

[0002]

2. Description of the Related Art FIG. 7 shows an example of a machine tool having a horizontal axis. In this machine tool, a horizontal shaft 101 is rotatably supported on a base 100, and one end of the horizontal shaft 101 is connected to a motor 10.
2, a bearing 103 orthogonal to the horizontal shaft 101 is attached to the center of the horizontal shaft 101, a shaft 104 is inserted into the bearing 103, and one end of the shaft 104 is a heavy object 105 such as a work, a pallet or a processing tool. Attach the shaft 104
A nut member 106 is provided at the other end of the nut member 10.
6, a rod screw 107 is screwed into the motor 6 and a motor 108 is driven so that the shaft 104 to which the heavy object 105 is attached moves forward and backward in a direction perpendicular to the horizontal shaft 101.

When the amount of protrusion of the shaft 104 increases, the amount of eccentricity of the heavy object 105 from the horizontal shaft 101 also increases, so that the torsional moment acting on the horizontal shaft 101 also increases. And when the torsion becomes large, the heavy object 10
5 falls below a predetermined position, and accurate numerical control cannot be performed. Therefore, as shown in FIG.
01 is fixed to a base end of a crank (lever) 109 at an end opposite to the motor 102, and a rod of a cylinder unit 110 is connected to a tip of the crank 109. On the other hand, the balance is achieved by applying a force in the direction opposite to the twisting direction.

A machine tool or a processing table device having a horizontal shaft is not limited to the structure shown in FIG. 7, and there are various structures. In each case, a crank is directly mounted on the horizontal shaft to correct the twist. .

[0005]

Some machine tools and machining table devices have one end of a horizontal shaft connected to a drive source such as a motor and the other end attached to another member such as a joint. . In the horizontal shaft having such a structure, there is no place for attaching a crank for returning the twist of the horizontal shaft. Also, even if the crank could be attached to the other end of the horizontal shaft,
There is a case where there is no space for disposing the cylinder unit near the horizontal axis.

[0006]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, a balance device according to the present invention has an intermediate shaft disposed at a position distant from a horizontal shaft on which a heavy object is eccentrically mounted. The transmission of force between the shaft and the shaft is possible, the crank is fixed to the intermediate shaft, and one end of a cylinder unit that applies a force in the direction opposite to the torsion direction to the horizontal shaft is connected to this crank. And

The term "horizontal axis" as used herein means an axis to which a torsional force acts when a heavy object is eccentrically mounted, and includes a slightly inclined axis. According to the above configuration, when a crank (lever) cannot be attached to the end of the horizontal shaft, the twist acting on the horizontal shaft is canceled even if the arrangement and direction of the cylinder units are limited due to space. be able to. As means for transmitting the force between the intermediate shaft and the horizontal shaft, it is conceivable to connect the gears fixed to the intermediate shaft and the horizontal shaft with a timing belt, a chain or an intermediate gear.

[0008]

Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a schematic perspective view of a processing station incorporating a processing table device to which a balancing device according to the present invention is applied, FIG. 2 is a plan view of the processing station, and FIG. 3 shows a side of the processing table device on which a balance mechanism is provided. FIG. 4 is an enlarged view in which a portion viewed from the direction A in FIG. 3 is partially cut away. The processing station is provided with a base 1, a machine tool 2 and a processing table device 3 are mounted on the base 1, and a pallet stocker 4 is arranged outside the base 1 so as to surround the machine tool 2. An automatic tool changer (A
TC) 5 are arranged. The machine tool 2 has a turn block 6 rotatable about a vertical axis in a horizontal plane with respect to the base 1. The pallet stocker 4 includes a plurality of pallet receiving frames 7, and these pallet receiving frames 7 and the processing table device. Numeral 3 is arranged substantially radially around the turning center of the machine tool 2, and the tip of a transfer line that also serves to carry in and carry out the work W faces within the turning range of the machine tool 2. I have.

As a result, the machine tool 2 faces the processing table device 3, the pallet stocker 4, and the work supply position 8. In the machine tool 2, a support portion 10 is attached to the turn block 6 around a horizontal axis 9 so as to be tiltable in a vertical plane by driving a motor 11, and a main bearing 12 slides on the support portion 10. Freely supported,
Rod screw 14 rotated by motor 13
By screwing a nut member 15 provided on the main bearing 12, the main bearing 12 moves forward and backward. In the main bearing 12, a main shaft (spindle shaft) 16 that is rotated at a high speed by a motor (not shown) is supported.

The main shaft 16 has a structure capable of selectively holding a pallet P for mounting a work and a processing tool T for performing processing such as cutting and drilling on the work. Then, the tilting movement of the support portion 10 in the vertical plane causes the main shaft 16 to face a direction suitable for the height of the processing table device 3, the pallet stocker 4, or the automatic tool changer 5. On the other hand, a base end of a crank 17 is attached to an end of the horizontal shaft 9 opposite to the motor 11.
7, a rod of a balance cylinder 18 is attached to the tip of the balance cylinder 18, and a force in a direction opposite to the twist given to the horizontal shaft 9 by a heavy object such as a pallet P held at the tip of the main shaft 16 is applied from the balance cylinder 18 to the horizontal shaft 9. To give to.

The balance mechanism applied to the machine tool 2 is the same as the conventional one. Next, the structure of the processing table device 3 will be described. In the processing table device 3, a support block 20 is rotatable about a vertical axis in a horizontal plane with respect to the base 1, and a horizontal axis 21 is attached to the support block 20. One end of the horizontal shaft 21 has a horizontal shaft 21
A motor 19 (see FIG. 2) for rotating the motor is provided. A processing table 22 is provided on the horizontal shaft 21.
The pallet P with the workpiece W attached to the processing table 22 is detachable. Here, the horizontal shaft 21 rotates together with the processing table 22, which is a heavy object, and the pallet P on which the work W is mounted. For example, the horizontal table 21 stops in a state where the processing table 22 is at a lateral position with respect to the horizontal shaft 21. Since the posture needs to be maintained during machining, a balance mechanism for canceling the twist acting on the horizontal shaft 21 is provided on the side opposite to the motor 22. As shown in FIGS. 3 and 4, the balance mechanism is provided with brackets 23 and 24 on the support block 20,
The base of the cylinder unit 25 is attached to the bracket 23, and one end of a rod 26 is attached to the bracket 24.

The bracket 23 has a plate 2
The lower end of 7 is fixed by welding or the like, and the tip of the rod 26 is attached to the tip of this plate 27 via a nut 28 so that the position can be adjusted. The plate 27 has a bearing 2
9, a horizontal shaft 30 is rotatably supported, a crank 31 is attached to one end of the horizontal shaft 30, a gear 32 is attached to the other end, and a rod 25a of the cylinder unit 25 is attached to the crank 31. Connected. On the other hand, a gear 33 is fixed to the other end of the horizontal shaft 21, and a timing belt 34 is stretched between the gears 32, 33 so that the force acting on the gear 32 is directly transmitted to the horizontal shaft 21. I have.

Here, when the processing table 22 is stopped in a state where the processing table 22 is at a lateral position with respect to the horizontal shaft 21 and is at a position where a torsional force is applied to the horizontal shaft 21, the timing belt 3
The upper side or the lower side (relative to the gears 32 and 33) of 4 is in a tension state, and a force in the falling direction (rightward force in FIG. 3) acts on the plate 27. In this state, an excessive force acts on the lower end mounting portion of the plate 27, so that the rod 26 prevents the tension plate 27 from falling down. Note that a rotary joint 35 is provided outside the gear 33 of the horizontal shaft 21. Since the rotary joint 35 is attached to the end of the horizontal shaft 21, a general balance mechanism as applied to the machine tool 2 cannot be employed, and the above-described structure is employed. Since the processing table 22 is attached to the horizontal shaft 21, the weight of the processing table 22 is
1 acts as a torsional moment. Then, the cylinder unit 25 is driven, and this driving force is applied to the crank 31,
Shaft 30, gear 32, timing belt 34 and gear 33
, A force in the direction opposite to the torsional force is applied to the horizontal shaft 21. Thereby, the twist generated by eccentrically supporting the processing table 22 on the horizontal shaft 21 is canceled, and the balance is maintained.

The maintenance of this balance is achieved by rotating the horizontal shaft 21 around 3
This can be achieved even when the processing table 22 is located at any position of 60 °. FIGS. 5 and 6 are diagrams similar to FIGS. 3 and 4 showing another embodiment of the balance mechanism. In this embodiment, a gear 36 is used instead of the timing belt 34. The other members are the same as those in the above-described embodiment, and thus the same reference numerals are given and the detailed description is omitted.
As means for transmitting the driving force of the cylinder unit 25 to the horizontal shaft 21, the force may be transmitted by a chain other than the timing belt and the gear.

[0015]

According to the present invention as described above,
For various reasons, such as space reasons and relationships with other members, when it is not possible to attach the crank that connects to the balance cylinder to the end of the horizontal shaft of a machine tool or table device, or move the cylinder unit itself from the horizontal shaft. Even if it is necessary to separate them, the twist acting on the horizontal axis can be canceled.

Therefore, there is no disadvantage that a heavy object such as a table, a work, a pallet, a work jig or the like which is eccentrically mounted on a horizontal axis of a machine tool or the like falls below a predetermined position. Accurate numerical control can be performed.

[Brief description of the drawings]

FIG. 1 is a schematic perspective view of a processing station incorporating a processing table device to which a balance device according to the present invention is applied.

FIG. 2 is a plan view of the processing station.

FIG. 3 is a side view showing a side of the processing table device on which a balance mechanism is provided.

FIG. 4 is an enlarged view of a part cut away from a portion viewed from a direction A in FIG. 3;

FIG. 5 is a view similar to FIG. 3, showing another embodiment.

FIG. 6 is a sectional view taken along line BB in FIG. 3;

FIG. 7 shows an example of a conventional balance device.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Base, 2 ... Machine tool, 3 ... Processing table device, 4
... Pallet stocker, 5 ... Auto tool changer (ATC), 6 ... Turn block, 7 ... Pallet receiving frame, 8 ... Work supply position, 9 ... Horizontal axis, 10 ... Support part,
11 ... motor, 12 ... main bearing, 13 ... motor, 14 ...
Rod screw, 15 nut member, 16 spindle (spindle shaft), 17 crank, 18 balance cylinder, 20 support block, 21 horizontal shaft, 22 motor, 23, 24 bracket, 25 cylinder unit, 26 rod, 27 plate, 28 nut, 2
9 ... bearing, 30 ... horizontal shaft, 31 ... crank, 32, 3
3, 36: gear, 34: timing belt, 35: rotary joint, P: pallet, T: machining tool, W: work.

Claims (2)

[Claims] 1. A balance device for applying a force in a direction opposite to a twisting direction of a heavy object to a horizontal shaft on which a heavy object is eccentrically mounted, wherein the balance device is provided at an intermediate position at a distance from the horizontal shaft. A shaft is arranged to enable transmission of force between the intermediate shaft and the horizontal shaft, and a crank is fixed to the intermediate shaft, and a force is applied to the crank in a direction opposite to the twisting direction with respect to the horizontal shaft. A balance device wherein one end of a cylinder unit is connected. 2. The balance device according to claim 1, wherein the transmission of the force between the intermediate shaft and the horizontal shaft is performed by using a timing belt, a chain, or an intermediate gear between gears fixed to the intermediate shaft and the horizontal shaft. A balance device characterized by being connected by a.