JP2008168355A - Roll processing apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To restrain deformation of a main spindle by keeping a bearing clearance between static pressure radial bearings which rotatably support the main spindle constant all the time by using a constant pressure ratio flow regurating valve, and to improve processing accuracy by accurately supporting the roll. <P>SOLUTION: The constant pressure ratio flow regulating valve 17 is provided on at least one hydraulic oil supply circuit 16 in static pressure pockets 12A, 12B, 13A, 13B, 14A, 14B, 15A, 15B, which are located at positions on which the load of the roll R works, among the static pressure pockets of the static pressure radial bearings 12, 13, 14, 15 of the main spindles 10, 11 supporting both ends of the roll R, thus keeping the bearing clearance constant. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a roll processing apparatus that processes a surface of a roll while supporting and rotating the roll horizontally, and in particular, a roll metal used for an optical film used for a liquid crystal screen and a lenticular lens used for rear projection. The present invention relates to a roll processing apparatus that requires precision processing of a mold or the like.

  Since the roll mold described above requires fine and extremely high-precision processing, it is necessary to accurately support the roll while suppressing run-out due to rotation and displacement of the axial center position. For this purpose, it is preferable that the main shaft supporting both ends of the roll is supported by a hydrostatic bearing.

  However, if the main shaft is supported by a hydrostatic bearing, the load of the roll acts on the hydrostatic bearing. For example, among the hydrostatic radial bearings that rotatably support the front side of the main shaft toward the roll, The pressure pocket has a smaller bearing gap in the lower static pressure pocket and a larger bearing gap in the upper static pressure pocket. On the other hand, in the hydrostatic pockets facing the upper and lower sides of the hydrostatic radial bearing that rotatably supports the rear side of the main shaft, the upper bearing gap is reduced and the lower bearing gap is increased.

  When the bearing clearance of each static pressure pocket changes in this way, when the roll is rotated at high speed, a difference in heat generation temperature is generated in each static pressure pocket, which deforms the main shaft and rotates the roll while supporting the roll accurately. The problem that cannot be done.

Conventionally, in a hydrostatic bearing, a so-called constant pressure ratio flow rate adjustment valve that can keep a bearing gap constant has been proposed (Patent Document 1). The constant pressure ratio flow rate adjusting valve takes in the pressure in the static pressure pocket and changes the flow rate of the pressure oil supplied to the static pressure pocket in accordance with the change in the pressure to keep the bearing gap constant.
JP-A-5-306718

  The present invention uses the constant pressure ratio flow rate adjusting valve to suppress the deformation of the main shaft so as to keep the bearing clearance of the hydrostatic radial bearing that supports the main shaft rotatably, and to accurately support the roll. An object of the present invention is to provide a roll processing apparatus capable of improving the processing accuracy.

  In order to achieve the above object, the present invention provides a roll processing apparatus for processing the surface of the roll by supporting both ends of a horizontally placed roll by opposing roll supporting main shafts, Among the hydrostatic radial bearings that rotatably support the front side and the rear side toward the roll, and a plurality of sets of hydrostatic pockets facing each other in these hydrostatic radial bearings, the roll is in a position where the load acts. A constant pressure ratio flow rate adjusting valve that is provided in at least one of the pressure oil supply circuits of the static pressure pockets facing each other and supplies pressure oil so as to keep the bearing gap of the static pressure pocket constant. It is characterized by that.

  The constant pressure ratio flow rate adjusting valve is configured such that the pressure of the static pressure pocket on the side where the bearing clearance increases due to the load of the roll is at least one of the opposing static pressure pockets of the set at the position where the load of the roll acts. It may be provided in the oil supply circuit. The pressure oil supply source of the static pressure radial bearing is preferably an accumulator tank that stores pressure oil pressurized by air pressure, and this accumulator tank stores a predetermined amount or more of pressure oil to cope with a power failure. It is preferable that it is comprised.

  According to the present invention, the bearing clearance can be kept constant by supplying pressure oil to the hydrostatic radial bearing of the main shaft via the constant pressure ratio flow rate adjusting valve as described above, thereby enabling the roll to rotate at a high speed. In addition, it is possible to reduce the difference in heat generation temperature between the static pressure pockets, and it is possible to obtain the effect of suppressing the deformation of the main shaft and accurately supporting the roll and improving the processing accuracy.

  The constant pressure ratio flow rate adjusting valve is supplied with pressure oil in the static pressure pocket on the side where the bearing clearance increases due to the load of the roll among the opposing static pressure pockets of the set at the position where the load of the roll acts. If it is provided in the circuit, the bearing clearance can be kept constant more easily and reliably, and if the pressure oil supply source of the hydrostatic radial bearing is an accumulator tank that stores pressure oil pressurized by air pressure Compared with the case of supplying from a pump, the pulsation, which is the pressure fluctuation of the pressure oil supplied to the static pressure pocket, is suppressed, and the roll can be supported extremely accurately and stably to improve the processing accuracy. If the accumulator tank is configured to store a predetermined amount or more of pressure oil, it can supply pressure oil to the static pressure pocket even in the event of a power outage and prevent bearing damage and other damage. Can.

  An embodiment of the present invention will be described below with reference to FIGS. In FIG. 1, R is a roll to be processed. Reference numerals 10 and 11 denote main shafts which are arranged opposite to each other on the same horizontal axis, and hold both ends of the roll R so as to be detachable.

  Both the main shafts 10 and 11 are rotatably supported by static pressure radial bearings 12, 13, 14, and 15, respectively, on the front side and the rear side toward the roll R. These static pressure radial bearings 12, 13, 14, and 15 are, as shown in FIG. 2, taking the static pressure radial bearing 12 as an example, and forming two sets of static pressure pockets 12A, 12B facing each other vertically and horizontally, (Vertical facing) 12C, 12D, (Left-right facing).

  Among the static pressure pockets 12A, 12B, 12C, and 12D, as described above, the pressure oil supply circuit 16 of the upper static pressure pocket 12A in the upper and lower position where the load of the roll R acts is provided with the static pressure as described above. A constant pressure ratio flow rate adjusting valve 17 is provided to keep the bearing gap of the static pressure pocket 12A constant by changing the flow rate of the pressure oil supplied to the static pressure pocket 12A according to the pressure change in the pocket 12A. Similarly, the static pressure radial bearing 14 on the front side of the main shaft 11 is also provided with a constant pressure ratio flow rate adjusting valve 17 in the pressure oil supply circuit 16 of the upper static pressure pocket 14A.

  On the other hand, the static pressure radial bearings 13 and 15 on the rear side of the main shafts 10 and 11 are provided with a constant pressure ratio flow rate adjusting valve 17 in the pressure oil supply circuit 16 of the lower static pressure pockets 13B and 15B. The pressure oil supply circuit 16 is connected to an accumulator tank 19 that is a pressure oil supply source via a temperature adjustment unit 18.

  In addition, the static pressure pockets (signs omitted) other than the static pressure pockets 12A, 14A, 13B, and 15B of the static pressure radial bearings 12, 13, 14, and 15 are temperature adjusted without going through the constant pressure ratio flow rate adjusting valve 17. The unit 18 is connected to an accumulator tank 19 which is a pressure oil supply source.

  Reference numerals 20 and 21 denote static pressure thrust bearings of the main shaft 10, each having a plurality of static pressure pockets opposed to both end faces of the flange 22 provided on the main shaft 10. Thus, the accumulator tank 19 is connected via the temperature adjusting unit 18. Reference numeral 23 denotes a drain for returning the spilled oil from each of the hydrostatic bearings 12 to 15, 20, 21 to the tank 24.

  A floating thrust 25 is provided at the rear end (right end in FIG. 1) of the main shaft 11. As shown in FIG. 3, the floating thrust 25 has ball bearings 26 and 27 as thrust bearings attached to the rear end of the main shaft 11 by a nut 29 via a spacer 28. The outer race side of the ball bearings 26 and 27 is fitted into the hole 31A of the housing 31 through the bare case 32, and supported by the guide pin 31B so as to be movable only in the axial direction. The housing 31 is attached to a main spindle head body (only a part of which is shown) 30 that rotatably supports the main spindle 11 via the hydrostatic radial bearings 14 and 15.

  The housing 31 is provided with pistons 33 and 34 for pressing the bare case 32 from the front and rear. Both pistons 33, 34 are provided such that their forward limit positions are restricted by step portions before and after the hole 31A, and each piston is retractable by a predetermined amount. The rear surfaces of the pistons 33 and 34 are configured so that the pressure oil supply circuit 16 and the tank 24 can be selectively connected by a switching valve 35, and the pistons 33 and 34 are connected to the pressure oil supply circuit 16 to move the pistons 33 and 34 to the forward limit position. The ball bearings 26 and 27 are fixed in the axial direction via the bare case 32, and connected to the tank 24 to release the pressure on the back side of the pistons 33 and 34, whereby the shafts of the ball bearings 26 and 27 are connected. It is designed to allow direction movement.

  In FIG. 1 again, the accumulator tank 19 is connected to a receiver tank 38 that stores high-pressure air obtained by increasing the pressure of pressurized air from a pressurized air source 36 such as factory air by a pressure-increasing valve 37. The pressure required for 12 to 15, 20 and 21 is applied to the accumulator tank 19.

  A pump 40 is connected to the accumulator tank 19 via a check valve 39, and the start and stop of the pump 40 is controlled by upper and lower liquid level gauges 41 and 42 provided in the accumulator tank 19. The pressure oil of a predetermined value or more is stored. Note that the rotational drive mechanism of the main shafts 10 and 11 and the axial movement mechanism of the main shaft 10 or 11 for attaching and detaching the roll R are not directly related to the present invention, and thus illustration and description thereof are omitted.

  Next, the operation of this apparatus will be described. When attaching the roll R to the main shafts 10 and 11, first, the back surfaces of the pistons 33 and 34 are connected to the pressure oil supply circuit 16 by the switching valve 35, and the pistons 33 and 34 are connected to the holes 31A as shown in FIG. The ball bearings 26 and 27 are fixed to the housing 31 by pressing against the front and rear step portions, and the thrust direction position of the main shaft 11 with respect to the main shaft head body 30 is fixed.

  Next, the roll R is attached to the main shafts 10 and 11. By mounting the roll R, the load of the roll R acts on the main shafts 10 and 11, and the bearings of the static pressure pockets 12B and 14B located below the front static pressure radial bearings 12 and 14 become smaller, The bearing gaps between the static pressure pockets 12A and 14A located are about to increase. On the other hand, in the hydrostatic radial bearings 13 and 15 on the rear side, the bearing gaps of the static pressure pockets located on the upper side are reduced, and the bearing gaps of the hydrostatic pockets 13B and 15B located on the lower side are going to be increased.

  When the bearing gap decreases, the pressure of the hydraulic oil in the static pressure pocket increases. Conversely, when the bearing gap increases, the pressure of the hydraulic oil in the static pressure pocket decreases. However, since each of the static pressure pockets 12A, 14A, 13B, and 15B in which the bearing clearance is to be increased is supplied with the pressure oil from the accumulator tank 19 through the constant pressure ratio flow rate adjusting valve 17, the static pressure pockets The flow rate of the pressure oil supplied to the static pressure pockets changes according to the pressure change of the pressure oil in 12A, 14A, 13B, 15B, and the bearing gaps of the static pressure pockets 12A, 14A, 13B, 15B are made constant. Hold.

  As described above, the bearing gap of one of the two static pressure pockets 12A, 14A, 13B, and 15B, which are opposed to each other in the vertical direction where the bearing gap is to be changed by the load of the roll R, is kept constant. The bearing gaps of the other static pressure pockets 12B, 14B, 13A, and 15A are also kept constant, and changes in the bearing gap due to the load of the roll R are suppressed. For this reason, even if the main shafts 10 and 11 are rotated at a high speed by a rotation drive mechanism (not shown), the difference in heat generation temperature between the static pressure pockets can be kept small, and the deformation of the main shafts 10 and 11 can be suppressed to accurately support the roll R. . Therefore, the processing accuracy is improved.

  In addition, since the pressure oil is supplied to the static pressure bearings 12 to 15, 20, and 21 from the accumulator tank 19 that is given a stable pressure by the receiver tank 38, the pressure oil is directly supplied from the pump. Generation | occurrence | production of such a pulsation is suppressed and the roll R can be supported correctly and stably, and the improvement of the processing precision of the roll R is achieved by this.

  Furthermore, since the accumulator tank 19 stores the pressure oil of a predetermined value or more by controlling the start and stop of the pump 40 by the liquid level gauges 41 and 42, the pressure oil is stored in each static pressure pocket even during a power failure. To prevent the occurrence of damage such as galling of the bearing.

  After the roll R is attached to the main shafts 10 and 11 as described above, before the processing of the roll R is started by rotating the main shafts 10 and 11, the switching valve 35 for the floating thrust 25 is switched to switch both pistons 33. , 34 is opened to the tank. As a result, even if the roll R expands and contracts due to, for example, a change in room temperature, the ball bearings 26 and 27 can move in the axial direction with respect to the housing 31, thereby allowing the main shaft 11 to move in the axial direction. Therefore, an excessive load does not act on the hydrostatic thrust bearings 20 and 21 of the main shaft 10 and damage such as galling does not occur, and the roll R can be supported accurately and stably. The processing accuracy of R can be improved.

  In the embodiment described above, among the static pressure pockets 12A, 12B, etc., facing each other at the position where the load of the roll R acts, the static pressure pocket 12A, etc. on the side where the bearing clearance increases due to the load of the roll R, etc. Although the example of connecting the constant pressure ratio flow rate adjusting valve 17 was shown, the pair of static pressure pockets 12A and 12B, the pair of 13A and 13B, the pair of 14A and 14B, and the pair of 15A and 15B, You may make it connect to a hydraulic circuit using a constant-pressure ratio flow control valve in a pair. In this case, the number of constant pressure ratio flow control valves increases and the hydraulic circuit becomes complicated, but it can be expected that the stability of the roll support is further increased. In the above-described embodiment, the example in which the pressure oil is supplied from the accumulator tank 19 to each of the hydrostatic bearings 12 and the like via the temperature adjustment unit 18 is shown, but the present invention is not limited to this. Alternatively, the pressure oil may be supplied directly from the pump 40.

  Furthermore, in the above-described embodiment, an example in which the pressure oil of the pressure oil supply circuit 16 for the hydrostatic bearing is used to fix the ball bearings 26 and 27 as the thrust bearing of the main shaft 11 to the bearing member 30 is shown. However, air pressure may be used. Furthermore, in the above-described embodiment, the example in which the ball bearings 26 and 27 can be moved back and forth by the pistons 33 and 34 in order to be able to cope with any expansion and contraction of the roll R has been shown. It is possible to implement various modifications, for example, only.

  The present invention is particularly suitable for a roll processing apparatus that requires precision processing such as a roll mold used for an optical film used for a liquid crystal screen and a lenticular lens used for rear projection, but is not limited thereto. The present invention can be widely applied to a roll processing apparatus that processes the surface of a roll while rotating the roll while supporting the roll horizontally with main shafts arranged opposite to each other.

The principal part schematic block diagram of the roll processing apparatus to which this invention is applied. FIG. 2 is a cross-sectional view taken along line AA in FIG. 1. FIG. 2 is an enlarged detailed longitudinal sectional view of the floating thrust shown in FIG. 1.

Explanation of symbols

10, 11 Main shaft 12, 13, 14, 15 Static pressure radial bearings 12A, 12B, 12C, 12D, 13A, 13B, 14A, 14B, 15A, 15B Static pressure pocket 16 Pressure oil supply circuit 17 Constant pressure ratio flow control valve 18 Temperature Adjustment unit 19 Accumulator tank 20, 21 Hydrostatic thrust bearing 22 鍔 23 Drain 24 Tank 25 Floating thrust 26, 27 Ball bearing 28 Spacer 29 Nut 30 Spindle head main body 31 Housing 31A Hole 31B Guide pin 32 Bare case 33, 34 Piston 35 Switching valve 36 Pressurized air source 37 Booster valve 38 Receiver tank 39 Check valve 40 Pump 41, 42 Level gauge R Roll.

Claims (4)

In the roll processing apparatus for processing the surface of the roll by supporting both ends of the roll placed horizontally by the opposing spindle for supporting the roll,
A hydrostatic radial bearing that rotatably supports a front side and a rear side toward the roll in each of the main shafts;
Among the plurality of sets of hydrostatic pockets facing each other of these hydrostatic radial bearings, provided in at least one of the hydrostatic pockets facing each other in the set at the position where the load of the roll acts, A constant pressure ratio flow adjustment valve that supplies pressure oil so as to keep the bearing clearance of the static pressure pocket constant;
The roll processing apparatus characterized by comprising.   The constant pressure ratio flow rate adjusting valve is configured to supply pressure oil in a static pressure pocket on the side where a bearing clearance is increased by at least the load of the roll among a set of opposed static pressure pockets at a position where the load of the roll acts. The roll processing apparatus according to claim 1, wherein the roll processing apparatus is provided in a circuit.   The roll processing apparatus according to claim 1 or 2, wherein the pressure oil supply source of the static pressure radial bearing is an accumulator tank that stores pressure oil pressurized by air pressure.   The roll processing apparatus according to claim 3, wherein the accumulator tank is configured to store a predetermined amount or more of pressure oil in response to a power failure.

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