JP4548581B2 - Super finishing board - Google Patents

Description

  The present invention relates to a super finishing machine for super finishing a rolling surface of an inner and outer ring of a bearing. More particularly, it relates to a super finishing board for ball bearings.

  For example, a rolling surface of an inner and outer ring such as a ball bearing that pivotally supports an arm of a hard disk device is required to have considerable accuracy, and is generally often superfinished with a superfinishing machine.

  In general, in a super finishing board, an operation for releasing the tip of the grindstone held by the grindstone holder from the workpiece groove is necessary for loading and unloading the workpiece, which is called a short index of the grindstone. Conventionally, this short index is performed on the grindstone holder side.

  Patent Document 1 discloses a superfinishing processing apparatus that can perform roughing to precise processing with a single device by using a grindstone holder that holds two types of grindstones having different particle sizes.

  Patent Document 2 discloses a grindstone holder that allows a pneumatic cylinder and a stopper to approach the workpiece, and a spring to disengage from the workpiece to ensure an accurate and reliable grindstone stop position.

  Further, Patent Document 3 detects the amount of movement of the pressurizing system that pressurizes the grindstone in order to prevent the variation in the grinding amount, and performs processing when the pressurizing system moves by an amount corresponding to the required grinding amount. A control device for a superfinishing machine is disclosed.

  Furthermore, Patent Document 4 discloses a superfinishing apparatus that can hold a plurality of grindstones on a holder arm of a grindstone holder and can perform roughing and precision machining with a single apparatus.

Prior art document information related to the invention of this application includes the following.
JP 59-115157 (2nd page, FIG. 1 etc.) Japanese Utility Model Publication No. 51-143294 (page 4, FIG. 1, etc.) JP-A-4-256572 (page 3, FIG. 2 etc.) Japanese Patent Laid-Open No. 58-111486 (page 3, FIG. 1 etc.)

  The problems to be solved by the present invention are as follows. Conventionally, there are double cylinder methods and low center-of-gravity methods using a slider mechanism for the short index of the grindstone holder, but the double cylinder method, for example, complicates the tip structure, so the tip weight increases and high speed oscillation is not possible There are problems such as high balance from the oscillation core and poor balance.

  In the case of the low center of gravity method, the structure of the tip becomes simple and the balance is improved, but the slide mechanism cannot follow the high-speed oscillation, and there is a risk of cracking at the peak of the slide or cracking when it becomes large There is. Further, wear of the slide portion occurs, and play occurs.

  The following two methods have been conventionally known for changing the core height for changing the workpiece model number. One is to change by moving the workpiece side. The other is to change by moving the grinding wheel side (vibrating head). When moving on the workpiece side, the apparatus becomes complicated and expensive. Moreover, when moving the grindstone side, there is a problem that it takes time to change the set.

The following is a summary of issues related to the short index of wheels.
(1) Conventionally, the short index of the grindstone has been performed on the grindstone holder side, but the grindstone holder side is large with a complicated structure and has a movable member at the end of the oscillation shaft, so failure is likely to occur.

  (2) Since the tip is large, the number of oscillations cannot be increased, which hinders cycle time reduction. In addition, a large inertia was generated, adversely affecting other related mechanisms.

The following summarizes the issues related to changing the center height by changing the workpiece model number.
(1) When changing on the work head side, a large and complicated thing called a saddle was moved up and down by a corner or a dovetail slide.

  (2) In the case of the oscillation shaft side, there are many mechanisms that sandwich the dedicated liner and that do not have a mechanism for the vertical movement, or even a ball bush.

  The object of the present invention is to make the tip of the oscillation shaft simple, small and light (grinding wheel pressurization / cylinder only), and a short index of the grinding wheel can be performed for each oscillation shaft. Since the guide can be performed by a linear guide and the short index is performed on the basis of the linear guide, it is to provide a super finishing board capable of adjusting the center height for each workpiece model number.

In order to achieve the above object, the super finishing board of the present invention is:
Super finishing board,
A grindstone holder that pressurizes and holds a grindstone for polishing the surface to be finished;
An oscillation shaft for supporting the grindstone holder to swing the grindstone holder;
A linear guide mechanism for changing the center height of the oscillation shaft;
And, based on the linear guide mechanism, a short index of the grindstone and a change in the center height of the oscillation shaft are performed.

  The present invention aims to improve the capital investment efficiency, and is aimed at improving productivity at a low cost and has the following remarkable effects.

(1) Since the structure is simpler than before, it can be handled with inexpensive equipment.
(2) Since the oscillation tip (grindstone holder) is small and light, the number of oscillations can be increased. This enables high speed grinding.
(3) The cycle time can be shortened. For this reason, productivity is improved.
(4) Since the oscillation tip is small and light, the frequency of failures can be reduced from the standpoint of maintenance.
(5) The set change time can be shortened because the set can be changed only by replacing the center height adjustment spacer for the part number.
(6) The setup can be changed easily.
(7) Anyone can handle it easily, and it can handle many kinds of small lots.

  Since the short index mechanism is placed on the linear guide on the oscillation shaft side and the center height is changed for each oscillation shaft so that the linear guide is used as a reference, the grindstone holder is only for grinding wheel pressurization. Further, the center height of the oscillation spindle for each workpiece model number can be changed based on the same linear guide.

  The terms “center height change” and “short index” used herein have the following meanings.

  The super finishing of the ball bearing is performed by oscillating a grindstone that matches the center of the track groove diameter of the workpiece with the center of oscillation. That is, when it is desired to change to a raceway groove of a ball bearing having a different size, it is necessary to move it by the difference of the oscillation center. This is called core height change.

  In super-finishing of a ball bearing, it is necessary to remove (remove) the grindstone from the raceway groove in order to load or unload the workpiece. This operation is called a short index. The stroke for short index varies depending on the ball bearing model number. Large ball bearings have a larger stroke.

  Since the short index mechanism is placed on the linear guide on the oscillation shaft side and the center height is changed for each oscillation shaft so that the linear guide is used as a reference, the grindstone holder is only for grinding wheel pressurization. Further, the center height of the oscillation spindle for each workpiece model number can be changed based on the same linear guide.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the drawings, the same parts are denoted by the same reference numerals. In addition, it is needless to say that the embodiments described below are merely illustrative of the present invention and are not limited in any way.

(First embodiment)
FIG. 1 is a partial sectional view showing a superfinishing apparatus 1 according to an embodiment of the present invention. FIG. 2 is a partial cross-sectional view showing the grindstone holder of the superfinishing apparatus 1, that is, the grindstone holder unit 10. The superfinishing apparatus 1 includes an oscillation shaft (oscillation spindle) 6 and a grindstone holder 10 (see FIG. 2) held on the oscillation shaft 6. The oscillation shaft 6 is supported by the linear guide mechanism 4 and can move up and down along the linear guide mechanism 4.

  A center height adjusting spacer 5 for adjusting the height of the oscillation shaft 6 can be exchanged between the base 21 and the oscillation shaft 6 in accordance with the model number of the workpiece W (see FIGS. 2 and 3). Is inserted. The center height adjusting spacer 5 is held in a fixed state on the base 21.

  An elevating cylinder 2 for moving the oscillation shaft 6 up and down and performing a short index on the grindstone 9 (see FIG. 2) is provided above the oscillation shaft 6 driven by a drive source (not shown). . The elevating cylinder 2 is driven by a drive source (not shown), but hydraulic, pneumatic, or other driving methods can be adopted.

  Between the elevating cylinder 2 and the oscillation shaft 6, an ascending adjustment spacer 3 is provided so as to be exchangeable, and restricts the elevating cylinder 2 from being raised more than necessary. The oscillation shaft 6 moves up and down along the linear guide mechanism 4 by driving the elevating cylinder 2, but the linear guide mechanism 4 may be another linear guide device such as a cross roller or a doughtail.

  Next, the details of the grindstone holder unit 10 that pressurizes the grindstone 9 will be described with reference to FIG. Since the grindstone holder unit 10 is held by the connecting member 13 fixed to the oscillation shaft 6, when the oscillation shaft 6 moves up and down, the grindstone holder unit 10 moves up and down together with the connecting member 13.

  The grindstone holder unit 10 includes a sleeve 7 fitted to the connecting member 13, a pressure piston 8 fitted to the inner circumference of the sleeve 7 so as to be slidable in the axial direction, and a grindstone fitted to the inner circumference of the lower end opening of the sleeve 7. The adapter 11 and the grindstone adapter 11 are fitted to the inner periphery of the grindstone adapter 11, and one end thereof is composed of a long grindstone 9 in contact with the pressure piston 8.

  The other end of the grindstone 9 faces the workpiece W so as to be able to come into contact therewith. In FIG. 2, the workpiece W is an inner ring such as a ball bearing, and the outer peripheral raceway surface is ground with a grindstone 9 to indicate superfinishing. Compressed air supplied from a compressed air source (not shown) is defined between the pressure piston 8 and the cap member 30 through a compressed air supply hole 29 from a passage (not shown) provided in the connecting member 13. The pressure chamber 28 is supplied. The cap member 30 is fitted to the connecting member 13, but is hermetically sealed with an O-ring 27.

  The passage 23 provided in the connecting member 13 communicates with an open chamber 26 defined between the pressure piston 8 and the grindstone adapter 11 through a radial through hole 24 provided in the sleeve 7. ing. The sleeve 7 is hermetically sealed with an O-ring 25 provided on the outer peripheral surface. Although the open chamber 26 is always supplied with compressed air, the open chamber 26 is always maintained at atmospheric pressure because the open hole 39 is provided. The grindstone adapter 11 is pressed into the sleeve 7 and held. The bolt 40 is attached to prevent the sleeve 7 from rotating. The sleeve 7 is fixed to the grindstone holder unit 10 by the cap member 30 after being inserted into the connecting member 13.

  The grindstone holder unit 10 having the above configuration operates as follows. The pressurizing piston 8 is pushed down by the air pressure in the pressure chamber 28, and a pressing force that presses the grindstone 9 against the workpiece W acts. It goes without saying that a desired pressure is set by a control mechanism (not shown). In order to separate the grindstone 9 from the workpiece W, the air pressure in the pressure chamber 28 may be canceled. At this time, when the pressurizing piston 8 descends to the bottom of the open chamber 26, the pressurizing piston 8 closes the through hole 24. This position corresponds to the minimum grinding wheel length, a pressure switch (not shown) detects a pressure increase in the passage 23, issues a warning that the grinding wheel is minimum, and the apparatus stops.

  Next, the present invention will be further described with reference to FIG. The oscillation shaft 6 moves up and down linearly along the linear guide mechanism 4 by the operation of the elevating cylinder 2. At this time, since the grindstone holder unit 10 fixed to the oscillation shaft 6 also moves up and down at the same time, the short index of the grindstone 9 can be performed only by the vertical movement of the oscillation shaft 6. Therefore, the grindstone holder unit 10 only needs to have a function to pressurize the grindstone 9, the apparatus can be simplified, and high-speed oscillation (vibration / oscillation) is possible.

  As described above, the lift adjustment spacer 3 is provided above the oscillation shaft 6 in a replaceable manner. The raising amount adjusting spacer 3 is inserted into the spacer receiving member 18 from the horizontal direction. The spring plunger 17 provided in the spacer receiving member 18 is engaged with the plunger receiving notch 19 provided in the lift adjustment spacer 3 so that the lift adjustment spacer 3 is fixed at a predetermined position.

  On the other hand, a center height adjusting spacer 5 for adjusting the center height is provided below the oscillation shaft 6 in a replaceable manner. The center height adjusting spacer 5 is inserted into the spacer receiving member 14 from the horizontal direction. A spring plunger 15 provided in the spacer receiving member 14 is fitted into a plunger receiving hole 16 provided in the core height adjusting spacer 5 so that the core height adjusting spacer 5 is fixed at a predetermined position.

  As the lift adjustment spacer 3 and the center height adjustment spacer 5, dedicated ones are used according to the model number of the workpiece W to be processed. The thickness T1 of the center height adjustment spacer 5 and the thickness T2 of the lift adjustment spacer 3 can be selected according to the model number (type) of the workpiece W as a predetermined machining partner. Since the lift adjustment spacer 3 and the center height adjustment spacer 5 can be easily attached and detached by the spring plunger, the set can be easily changed.

  In FIG. 3, the work W is an outer ring, and a U-shaped grindstone adapter 22 different from that in FIG. 2 is used to process the inner circumferential raceway surface. In this case, the grindstone 9 (not shown in FIG. 3) is provided on the lower surface near the tip of the lower arm 22a of the grindstone adapter 22.

(Second embodiment)
FIG. 4 is a schematic perspective view showing the superfinishing apparatus of the second embodiment of the present invention. In the second embodiment, a ball screw mechanism and an AC servo motor are used in place of the lift adjustment spacer, the center height adjustment spacer and the lifting cylinder 2 of the first embodiment. Other configurations are almost the same as those of the first embodiment.

  The oscillation shaft 6 is fixed to the linear guide mechanism 4 and moves up and down in the direction of arrow A in the figure along the linear guide mechanism 4. The linear guide mechanism 4 is moved up and down by a ball screw mechanism 35. The ball screw mechanism 35 is driven by the AC servo motor 31 via a pulley 32 fixed to the rotation shaft of the AC servo motor 31, a belt 33, and a pulley 34 fixed to the ball screw mechanism 35.

  In addition, the oscillation shaft 6 is clamped via a leaf spring 38 by a clamp cylinder 37 that is driven by air or hydraulic pressure and is displaced in the direction of arrow C in order to prevent micro-vibration due to oscillation motion during machining. The reason for using the leaf spring 38 is that the linear guide of the linear guide mechanism 4 does not make a Brinell impression.

One end of the oscillation shaft 6 is connected to a connecting rod 39 connected to a drive mechanism (not shown) by the operation of the connecting rod 6, grindstone holder 10 fixed to the other end of the oscillation axis 6 by an arrow B It can swing in the direction.

  In the second embodiment, as in the first embodiment, the pair of linear guide mechanisms has a change in the center height of the oscillation shaft 6 that supports the grindstone holder 10 and a short index. However, in the second embodiment, two spacers, that is, a positioning height adjustment spacer and a core height spacer are not required. Since the thickness of the spacer differs depending on the model number, it was necessary for the operator to go around the back of the device and replace it when changing the set. There was also the possibility of mistaking the spacer. Therefore, such inconvenience is eliminated.

  In addition, since automated equipment including the apparatus has a small gap between the apparatuses, it is necessary to go behind the apparatus. For this purpose, it is necessary to move a considerable distance apparatus. In the second embodiment, a ball screw and an AC servo motor are used in place of the cylinder and spacer, and the mechanism (position change / short index) and positioning (position according to the number of set types) can be performed.

  Thus, it is only necessary to input the center height position and the index amount on the operation panel on the front side of the apparatus. That is, since the two spacers are exchanged, there is no need to turn to the back side of the apparatus. Further, if these values are registered and stored, if the model number is designated at the time of changing the set, it automatically moves to the registered value to complete the setting, and anyone can easily and reliably change the set.

  It is preferable to use a ball screw with a precision grade and an AC servo motor with a resolution down to a micrometer, but it goes without saying that the accuracy can be selected and set as required. However, the mutual dimensions of the workpiece core and the oscillation shaft need to be taken out in advance.

  It can be applied to applications that superfinish the rolling surfaces of inner and outer rings of bearings such as ball bearings.

It is a fragmentary sectional view which shows the super finishing apparatus of the Example of this invention. It is a fragmentary sectional view which shows the grindstone holder unit of the super finishing apparatus of the Example of this invention. It is a schematic perspective view which shows the super finishing apparatus of the Example of this invention. It is a schematic perspective view which shows the super finishing apparatus of 2nd Example of this invention.

Explanation of symbols

1: Super finishing board 2: Lifting cylinder 3: Lifting amount adjusting spacer 4: Linear guide mechanism 5: Center height adjusting spacer 6: Oscillation shaft 9: Grinding wheel 10: Grinding wheel holder unit 31: AC servo motor 35: Ball screw mechanism

Claims (4)

A super finishing machine that super-finishes the raceway groove of a workpiece that is an inner ring or outer ring of a ball bearing ,
A grindstone holder that pressurizes and holds a grindstone for polishing the raceway groove of the workpiece ;
An oscillation shaft that rotatably supports the grindstone holder in order to rotate and swing the grindstone holder;
A linear guide mechanism for changing the center height so that the center of rotation and oscillation of the oscillation shaft coincides with the center of the raceway groove diameter of the workpiece ;
The oscillation shaft is supported by the linear guide mechanism, and by moving the oscillation shaft and the grindstone holder up and down along the linear guide mechanism, the short index of the grindstone and the core of the oscillation shaft A super finishing board characterized by high changes.   The super finishing board according to claim 1, further comprising an elevating cylinder that moves the oscillation shaft up and down along the linear guide mechanism.   The lift amount regulating spacer is provided between the oscillation shaft and the lifting cylinder, and a center height adjusting spacer is provided on the oscillation shaft. Super finishing board.   The super finishing board according to claim 1, wherein the linear guide mechanism is moved by a ball screw mechanism, whereby a core height change and a short index are performed.

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