JPH0578437U - Bearing device - Google Patents

Abstract

(57) [Abstract] [Purpose] The present invention is a bearing capable of appropriately adjusting and controlling the sliding slide surface pressure of a slide table slidably supported on a bed by a hybrid bearing according to the load weight of the slide table. Provide a device. [Structure] A hydraulic cylinder device 32 for supporting a slide table 8 is provided on a roller portion 27 of a hybrid slide bearing, and a weight detection device 39 for detecting a load weight of the slide table 8 is provided.
It is characterized in that the controller 35 adjusts the oil pressure supplied to the hydraulic cylinder device 32 according to the weight detected by the control device 35.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a bearing device for a sliding surface of a machine tool.

[0002]

[Prior Art]

 In a machining center or the like, in the case of sliding slides of a slide table and a rotary table constituting a work table, when the weight of a moving object becomes heavy, the contact surface pressure applied to the slide becomes large. If this contact surface pressure becomes large, stick-slip easily occurs, resulting in poor positioning accuracy and processing accuracy.

In order to avoid this, there are some which use a hybrid slide bearing in which a slide slide and a roll slide are combined. In this hybrid slide bearing, a constant preload is applied to the roller by a disc spring, and a constant weight is always shared by the roller.

[0004]

[Problems to be solved by the device]

 It is very difficult to adjust the preload by the disc springs due to variations in the characteristics of the disc springs and the sensitive changes in the output value due to slight changes in the deflection of the disc springs. In addition, since the pan / bread can only bear a constant load of the weight of the moving object (table + work, etc.), there is a problem that the slide surface pressure changes due to the change in weight, and optimal control cannot be performed.

An object of the present invention is to provide a bearing device in which the sliding slide surface pressure is constant irrespective of the weight variation, the positioning accuracy is stabilized, and the followability during high-speed feed processing is improved.

[0006]

[Means for Solving the Problems]

 A feature of the present invention that achieves the above object is to provide a slide table supported linearly through a hybrid slide bearing consisting of a slide slide and a roller slide on the bed, and a roller of the hybrid slide bearing. A hydraulic cylinder device that drives the slide unit up and down to support the slide table, a hydraulic source that supplies pressure oil to the hydraulic cylinder device, a weight detection device that detects the load weight of the slide table, and a weight detection device that detects the weight. And a control device that adjusts the hydraulic pressure supplied to the hydraulic cylinder device according to the weight detected by the detection device.

[0007]

[Action]

 With the above configuration, the weight detection device detects changes in the load weight of the slide table, and the hydraulic pressure supplied to the hydraulic cylinder device of the roller portion of the hybrid slide bearing is adjusted according to the load weight to determine the sliding surface. The pressure is always kept constant.

[0008]

【Example】

 An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a plan view showing an example of a machine tool using the present invention. 1 is a machining center, a bed 2, a column 3 provided on the bed 2 so as to be movable back and forth, and this column. 3 includes a spindle head 5 which is vertically movable, and a work table 7 arranged on the bed 2 in front of the column 3, and 5a is a spindle which is rotatably supported by the spindle head 5. Reference numeral 4 is a servomotor for moving the column 3 forward and backward, and 6 is a servomotor for moving the spindle head 5 up and down.

The work table 7 is guided by a slide table 8 movably in a left-right direction which is orthogonal to the forward / backward movement direction of the column 3, and a rotary table 10 rotatably guided on the slide table 8. The pallet 11 on which the work is placed is carried in and out on the rotary table 10. Reference numeral 9 is a servomotor for moving the slide table 8 left and right. A clamp member 13 for the pallet 11 is provided on the turntable 10.

Reference numeral 13 denotes a pallet changer arranged in front of the work table 7. The pallet changer 13 is provided with a replacement driving device 15 provided with a hook 16 which is movable in a direction orthogonal to a horizontal direction of the slide table 8 and a left and right position of the replacement driving device 15. And pallet support bases 14a and 14b.

Reference numeral 17 denotes a numerical control device, which is connected to an input device 18 and a memory 19. The numerical control device 17 and the servo motor 4 for advancing and retracting the column 3, the servo motor 6 for moving the spindle head 5 up and down, and the slide table. 8 are connected to the left and right moving servomotors 9 via pulse distribution circuits 20a, 20b and 20c and drive circuits 21a, 21b and 21c, respectively. The numerical control device 17 and the exchange driving device 15 for the pallet 11 are connected via a sequence controller 22.

A detailed configuration of the work table 7 will be described with reference to FIGS. 2 and 4. The sliding table 8 is slidably guided to the bed 2 through a plurality of sliding surface inner surfaces 30 of a flat surface portion and an upright surface portion. One of them is the roller slide by the roller 31, and constitutes a hybrid slide bearing by the sliding slide and the roller slide.

The rotary table 10 is rotatably guided by a support shaft 23 provided upright in the center of the slide table 8, and guide surfaces for sliding slide rotation at a plurality of flat portions on the slide table 8. It is supported via 25. The slide table 8 is provided with a plurality of rollers 27 and a plurality of hydraulic cylinders 26 for clamping, which press the rollers 27 against the guide surface 25 at the indexing position of the rotary table 10 to restrain the rotary table 10, in the rotating direction of the rotary table 10. There is. The rotary table 10 is rotationally indexed by a motor (not shown) via a worm 28 and a worm wheel 29.

The clamp member 12 of the pallet 11 is provided on a clamp cylinder 24 arranged on the rotary table 10.

Therefore, the present invention has a piston 33 connected to the roller 31 and supports the slide table 8 by applying hydraulic pressure to the piston 33, and the hydraulic cylinder device 32 A hydraulic pressure source for supplying pressure oil, a weight detection device for detecting the load weight of the slide table 8, and an oil pressure supplied to the hydraulic cylinder device 32 according to the weight detected by the weight detection device. And a control device. A plurality of the rollers 31 and the hydraulic cylinder device 32 are provided on the lower surface of the slide table 8 in the sliding direction, and the rollers 31 roll on the guide surface 30.

A weight detection device for detecting the load applied to the slide table 8 and a first control device for adjusting the oil pressure supplied to the hydraulic cylinder device 32 according to the weight detected by the weight detection device. An example will be described with reference to FIG.

The hydraulic cylinder device 32 is connected to a hydraulic pump 34 via a pressure reducing valve 35 by piping. The clamp cylinder 24 of the pallet 11 provided on the rotary table 10 is connected to the hydraulic pump 36 via a first switching valve 37 and a second switching valve 38.

The first switching valve 37 has a clamping port 37a and an unclamping port 37b, and the second switching valve 38 has a clamping and unclamping port 38a and a hydraulic block port 38b. There is.

In the weight detection device for detecting the load applied to the slide table 8, a pressure sensor 39 is provided on the hydraulic pipe of the clamp cylinder 24 of the pallet 11, and the first switching valve 37 is attached to the unclamp port. The pressure sensor 39 detects a pressure that balances the weight on the clamp cylinder 24 when the pressure is switched to 37b and switched to the hydraulic blocking port 38b of the second switching valve 38. A load cell may be used instead of the pressure sensor 39. In this case, a load cell is provided on the rotary table 10, and a pallet is placed on this load cell to detect the weight of the pallet.

The pressure sensor 39 is connected to the control valve 35 via an amplifier 40 and a gate circuit 41, and the gate circuit 41 is connected to the sequence controller 22.

The operation of the structure of the first embodiment of the present invention will be described with reference to the flowchart of FIG. First, the slide table 8 is positioned on the pallet support base 14a side of the pallet changer 13 (step 50). Next, the hook 16 is advanced (step 51). Thereafter, the second switching valve 38 is switched to the clamping and unclamping port 38a side, and the first switching valve 37 is switched to the unclamping port 37b side to unclamp the pallet 11 by the clamp cylinder 24 (step 52). Then, the pallet 11 is engaged with the hook 16. The hook 16 is retracted (step 53) to take out the pallet 11 to the pallet support base 14a side, and the pallet support base 14a supporting the pallet 11 is lowered (step 54). As a result, the engagement between the pallet 11 and the hook 16 is released.

Next, the slide table 8 is positioned on the pallet support base 14b side of the pallet changer 13 (step 55), the pallet support base 14b supporting the pallet 11 is raised (step 56), and the pallet 11 and the hooks are hooked. 16 and are engaged. Next, the hook 16 is moved forward (step 57) to carry the pallet 11 on the pallet support base 14b onto the rotary table 10.

When the pallet 11 is loaded onto the rotary table 10, the second switching valve 38 is switched to the hydraulic block port 38b to detect the pallet weight (step 58). The pallet weight is detected on the clamp cylinder 24 when the pallet weight is switched to the hydraulic block port 38b of the second switching valve 38 with the first switching valve 37 switched to the unclamping port 37b as described above. A pressure sensor 39 detects the pressure that balances the weight.

The weight detection signal of the pressure sensor 39 is amplified by the amplifier 40 and transmitted to the gate circuit 41. Further, the signal from the amplifier 40 is changed by the data latch signal transmitted from the sequence controller 22 to the gate circuit 41. 35 is input. As a result, the pressure reducing valve 35 is controlled to adjust the hydraulic pressure supplied to the hydraulic cylinder device 32 of the roller 31 (step 59). As a result, the weight of the slide table 8 supported by the roller 31 changes, and the weight of the slide table 8 supported by the sliding slide guide surface 30 changes. That is, the surface pressure of the sliding slide guide surface 30 can be optimally controlled according to the load weight acting on the slide table 8.

After that, the first switching valve 37 is switched to the clamping port 37a and the second switching valve 38 is switched to the clamping and unclamping port 38a to clamp the pallet 11 on the rotary table 10 (step 60). , The hook 16 is retracted (step 61) to complete the cycle.

FIG. 4 shows a second embodiment of the present invention. In the second embodiment, the construction of the work table 7 and the weight detecting device are the same as those in the first embodiment, and the oil pressure supplied to the hydraulic cylinder device 32 of the roller 31 is adjusted by the adjusting control means. Has changed. That is, a plurality of pressure reducing valves 42, 43, and 44, whose pressures P1, P2, and P3 have already been adjusted, are arranged in the pipe from the hydraulic pump 34 to the hydraulic cylinder 32, and based on the weight signal detected by the pressure sensor 39. By selecting and controlling the plurality of pressure reducing valves 42, 43, 44 by the sequence controller 17, the hydraulic pressure to be supplied to the hydraulic cylinder device 32 of the roller 31 is adjusted in the same manner as in the first embodiment. It is possible to optimally control the surface pressure of the guide surface 30 for use according to the weight.

[0027]

[Effect of the device]

 As described above, according to the present invention, in a slide table supported linearly through a hybrid slide bearing composed of a slide slide and a roller slide on a bed, the roller portion of the hybrid slide bearing is driven vertically. And a hydraulic cylinder device that supports the slide table, a hydraulic pressure source that supplies pressure oil to the hydraulic cylinder device, a weight detection device that detects the load weight of the slide table, and a weight detection device that detects the weight. Since the control device adjusts the hydraulic pressure to be supplied to the hydraulic cylinder device according to the weight, the sliding table load weight, that is, the sliding slide surface pressure of the slide table is appropriately adjusted according to the work weight. Adjusted and controlled to stabilize slide table positioning accuracy and high-speed feed It is improved follow-up of the time.

[Brief description of drawings]

FIG. 1 is a plan view showing an embodiment of a machine tool using the device of the present invention.

FIG. 2 is a sectional view showing a first embodiment of the device of the present invention.

FIG. 3 is a flowchart showing the operation of the device of the present invention.

FIG. 4 is a sectional view of the essential parts of a second embodiment of the device of the present invention.

[Explanation of symbols]

 2 bed 8 slide table 10 rotary table 30 guide surface for sliding slide 31 roller 32 hydraulic cylinder device 34 hydraulic pump 35 pressure reducing valve 39 pressure sensor

Claims (1)

[Scope of utility model registration request] 1. A slide table supported on a bed so as to be linearly movable via a hybrid slide bearing consisting of a sliding slide and a roller slide by a roller, and the roller portion of the hybrid slide bearing is driven in the vertical direction to perform the slide. A hydraulic cylinder device that supports the table, a hydraulic source that supplies pressurized oil to the hydraulic cylinder device, a weight detection device that detects the load weight of the slide table, and the hydraulic pressure according to the weight detected by the weight detection device. A bearing device, comprising: a control device that adjusts the hydraulic pressure supplied to the cylinder device.