JP5823181B2 - Grinder - Google Patents

Description

  The present invention relates to a grinding machine.

  Conventionally, a headstock having a chuck and a spindle for holding and rotating a long grinding target object having a circular cross section is attached to the frame base, and the main spindle base is mounted on the frame base along the axial direction of the grinding target object. There is known a grinder capable of grinding with a grindstone while moving (advancing) to the side. In addition, when a long grinding object with a small diameter is ground with a grindstone, the grinding object becomes in an unstable state due to the load acting on the grinding object, and the appropriate grinding process with the grindstone cannot be performed. As a grinding machine specializing in grinding small and long grinding objects to prevent / suppress, it is the part of the grinding object located outside the spindle and chuck and closer to the headstock than the grinding wheel A grinding machine provided with a support portion that supports the position is also considered (see Patent Document 1).

  In Patent Document 1, a support portion that supports a portion of a grinding object located outside the chuck is fixed to a frame base, and the headstock is ground on the frame base in a state where the grinding object is supported by the support portion. There has been disclosed a grinding machine configured to be able to grind to an intended value with a grindstone while moving the grinding object forward by moving the grinding object in the axial direction. That is, when the elongated grinding object supports the end part on the headstock side in a cantilevered manner, the center of rotation is unstable and swings. Therefore, the above-described grinding machine employs a configuration in which the grinding object is rotated by supporting the two ends of the grinding object near the headstock and the grindstone so that the grinding object can be rotated stably. The state is obtained.

JP 2002-48151 A

  However, since the conventional grinding machine described above has the support portion fixed to the frame base, it is natural that the position of the support portion on the frame base cannot be changed. Accordingly, a portion of the object to be ground that is closer to the main shaft than the portion to be ground and corresponds to the separation distance between the grindstone and the support portion is caused by the forward movement of the head stock during the grinding processing. Will always pass through the support. As a result, if the part where the external surface is processed with a male screw or a recess or a hole (processed part) coincides with the part that passes through the support part before the grinding process, The processed part may be damaged by passing through the support part during the grinding process.

  In addition, the grinding machine disclosed in Patent Document 1 in which the support portion is fixed to the frame base assumes only a small-diameter long material having a small diameter and an axial dimension equal to or larger than a predetermined value as an object to be ground. For example, when grinding a part that does not need to support the grindstone side part with the support part because the diameter is sufficiently thick or the axial dimension is sufficiently short, the support part fixed to the frame base is Not only will it become an unnecessary part and it will become an over specification, but depending on the case, it may become the hindrance of an appropriate grinding process.

  The present invention has been made paying attention to such problems, and the main purpose is to provide stable rotation even if the object to be ground is small in diameter and long, and in the vicinity of the grindstone. In addition to being able to change the part that supports the object to be ground, suitable grinding for small-diameter long materials as well as suitable for non-small-diameter long materials without excessive specifications An object of the present invention is to provide a grinding machine capable of processing.

  That is, the present invention relates to a grinding machine for grinding a rod-shaped grinding object by rotating a grindstone provided on a frame base. Here, the “bar shape” in the present invention is a concept including both a columnar shape (solid) and a cylindrical shape, and it is not particularly limited whether or not the cross-sectional shape is a perfect circle. Further, the number of grindstones may be either 1 or plural, and may be either an external grinding grindstone for grinding the outer surface of the grinding object or an internal grinding grindstone for grinding the inside of the grinding object. .

The grinding machine according to the present invention, comprising a chuck unit for holding an end portion of the counter-grinding side of the grinding object, and the spindle portion which causes rotation drive about its axis across the grinding object together with the chuck portion A headstock having a rotation holding portion and mounted on the frame base so as to be movable in the axial direction of the grinding object, and extending in parallel with the axial direction of the grinding object and extending in the axial direction of the grinding object A movable body main body that is movable, and a holding section that is detachably attached to the headstock and holds the movable body main body so as to be movable in the axial direction, and is not held by the chuck portion of the object to be ground. selecting a mode to expand and contract independently of the distance between the support point and the chuck portion for supporting the part and mode expanding and contracting in accordance with the movement of the headstock and the support point and the moving distance of the headstock and the chuck portion Possible And stretching mechanism, a support for supporting a portion of the headstock side of the grinding wheel in the vicinity of the grinding wheel of and grinding the object attached to the end of the grinding side of the movable body as a support point, on the frame base Provided with a stopper that restricts the movement of the movable body to the grindstone side , supports the object to be ground at the support point by the support portion, and restricts the movement of the movable body to the grindstone side by the stopper. Along with the movement of the headstock which gradually approaches the grinding wheel side along the axis direction of the grinding object, the distance between the chuck portion and the supporting point is gradually shortened while the grinding object is closer to the grinding wheel side than the supporting point. It is characterized in that the portion can be ground with a grindstone.

With such a grinding machine, one end of the object to be ground is held by the chuck portion of the headstock, and is supported at the portion near the other end and closer to the headstock than the grindstone. Since the point is supported by the support portion, the object to be ground rotates stably without causing vibration. Moreover, since the support part can be attached to and detached from the headstock, and the distance between the chuck part of the rotation holding part and the support point can be expanded and contracted by an expansion / contraction mechanism, it is compared with an aspect in which the support part is fixed on the frame base. Thus, there is a structural difference in that the support point by the support portion can be changed as appropriate. In other words, since the support point by the support part can be appropriately changed in the axial direction of the object to be ground, the object to be ground has a shape or a part that is not suitable for support by the support part. In some cases, the support point can be set at a position that avoids the location. Therefore, if a predetermined part on the outer surface of the object to be ground has already been subjected to processing such as a male thread or a recess or a hole before the grinding process, the support part is positioned at a position avoiding the processed part. By setting the support point, it is possible to prevent the processed part from being damaged when passing through the support part.

Here, with regard to the expansion / contraction mechanism, “to extend / contract the distance between the support point and the chuck part as the headstock moves” means to extend / contract the distance between the support point and the chuck part simultaneously with the movement of the mainstock. In addition, “to extend / contract the distance between the support point and the chuck part independently of the movement of the headstock” means that the support point and the chuck part are not moved (in a stopped state). It means that the distance is expanded and contracted. In the following description, “the distance between the support point and the headstock” is synonymous with “the distance between the support point and the chuck portion”.

Further, since the grinding machine of the present invention has the expansion / contraction mechanism detachably attached to the headstock, when the object to be ground is a small diameter and long one, the expansion / contraction mechanism is attached to the spindle stock. By using it, it is possible to support the part that is not held by the chuck part of the object to be ground and that is close to the grindstone side with the support part, and grind it in a stable state with respect to a small-diameter long object. Processing can be performed. On the other hand, in cases where the grinding object side is not required to be supported by the support part, such as when the diameter of the grinding object is sufficiently thick or the axial dimension is sufficiently short, the telescopic mechanism is By removing from the base, it is possible to eliminate the possibility that proper grinding processing will be hindered by the presence of the support part while avoiding excessive specifications, even for parts that do not fall under `` small diameter long '' Appropriate grinding can be performed.

  Further, in the grinding machine of the present invention, the support portion supports the outer peripheral surface of the object to be ground at points different from each other in the circumferential direction from below (including directly below and obliquely below), and the object to be ground If the outer peripheral surface of the part is provided with a pressing portion that presses the outer peripheral surface from above (including directly above and obliquely upward) toward the axis of the grinding object, the outer peripheral surface of the rotating grinding object is circumferentially It can be supported at three different points, and the object to be ground can be supported in a stable state. In particular, with such a support portion, it is possible to keep pressing the object to be ground from above with a linear pressure toward the axis of the object to be ground. If it is a mode of pressing with the pressure roller, it is possible to prevent or suppress the so-called chattering phenomenon of the grinding object due to the “spinning” that the pressure roller rotates together with the rotation of the grinding object. Stable machining can be performed with high accuracy.

  In addition, in order to obtain a good support state with a support portion even for a plurality of types of grinding objects having different outer edge shapes, it is possible to adjust the separation distance between the tip portions of at least a pair of support main body portions. It is preferable to configure. In addition, in this invention, in addition to the separation distance of the front-end | tip parts of a pair of support main-body part, the height position of the front-end | tip part of the press part with respect to a grinding target object can also be comprised so that adjustment is possible.

  Furthermore, in the grinding machine of the present invention, if the sintered diamond is attached to each of the supporting main body portions at the tip portion that contacts the grinding object and the tip portion that contacts the grinding object among the pressing portions, It is possible to effectively suppress wear / damage of a portion directly supporting the rotating grinding object among the support main body portion and the pressing portion constituting the support portion.

  In the present invention, a grinding machine including a primary grinding wheel for performing primary grinding and a secondary grinding wheel for performing secondary grinding is configured, and each of these grinding wheels is mutually in the axial direction of the object to be ground. It is possible to move in a direction perpendicular to the axis direction of the grinding object at a spaced position, and each of these wheels moves toward the direction of sandwiching the grinding object, and the headstock moves toward the grinding wheel side along the axis direction. Can be set at the same time, and primary grinding and secondary grinding can be performed by each rotating grindstone. With such a grinding machine, during the grinding process, the grinding wheel at a position relatively far from the spindle side along the axial direction of the grinding wheel for primary grinding and the grinding wheel for secondary grinding moves the tip side of the object to be ground. Since it functions as a presser to press, even a small-diameter and long grinding object can be properly ground. Furthermore, by simultaneously moving the headstock and rotating the wheels, the primary grinding wheel is not operated during the primary grinding process using the primary grinding wheel, and the primary grinding process is completed after the primary grinding process using the primary grinding wheel is completed. Each grinding wheel (primary grinding wheel, secondary grinding) without incurring a decrease in processing accuracy compared to the case where secondary grinding is performed with the grinding wheel for secondary grinding while the operation of the grinding wheel is stopped. The overall processing time by the grinding wheel) can be shortened.

  The grinding machine according to the present invention employs a configuration in which the support portion is not fixed to the frame base, and an extension mechanism for expanding and contracting the distance between the support point by the support portion and the headstock is detachably attached to the headstock. Therefore, it is possible to realize stable rotation of a small-diameter and long grinding object and to change a portion (support point) that supports the grinding object in the vicinity of the grindstone. When the object to be ground is not small and long, it is possible to remove the telescopic mechanism from the headstock so that it can be properly ground without excessive specifications. Is possible.

1 is an overall schematic diagram of a grinding machine according to an embodiment of the present invention. The top view of the grinding machine which concerns on the same embodiment. The A direction arrow directional view of FIG. The BB direction arrow directional view of FIG.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

  As shown in FIGS. 1 to 4, the grinding machine 1 according to the present embodiment includes a frame base 2, a primary grinding wheel 31 that is provided on the frame base 2 and grinds the grinding target object W by rotation, and secondary grinding. A spindle that has a grindstone 32 and a rotation holding portion 4 that rotatably holds the entire grinding object W and is movable in the axial direction X of the grinding object W (hereinafter sometimes referred to as the X-axis direction). A base 5, a telescopic mechanism 6 that is attached to the headstock 5 and supports the grinding object W and a distance between the headstock 5, and each grindstone of the grinding object W that is attached to the telescopic mechanism 6 A support portion 7 is provided that supports a portion closer to the headstock 5 than the (grinding stone 31 for primary grinding, the grinding stone 32 for secondary grinding) as a support point.

  Here, in the present embodiment, as shown in FIG. 1 and the like, the grinding object W is exemplified by a solid rod-shaped object made of, for example, a hard material. In particular, the grinding machine 1 with the telescopic mechanism 6 attached to the head stock 5 can be suitably ground even if the workpiece W is a high hardness and brittle material.

  The frame base 2 has a flat upward surface 21, and the headstock 5 is provided on the upward surface 21 so as to be movable in the axial direction X of the workpiece W, and each grindstone (primary grinding grindstone 31, secondary grindstone 31 The grinding wheel 32) is provided so as to be movable in a direction Y (hereinafter sometimes referred to as a Y-axis direction) orthogonal to the axial direction X of the grinding object W.

  The grinding wheel 31 for primary grinding and the grinding wheel 32 for secondary grinding are each supported by a slide support 33 that is slidable in the Y-axis direction on the frame base 2. In the present embodiment, as the primary grinding wheel 31 and the secondary grinding wheel 32, disk-shaped grinding wheels that rotate around an axis parallel to the axis Wa of the grinding object W and grind the outer surface of the grinding object W are used. Applicable. In addition, each grindstone (the grindstone 31 for primary grinding, the grindstone 32 for secondary grinding) is each comprised so that fine adjustment of the position of an X-axis direction is possible. In the present embodiment, as shown in FIG. 2, the primary grinding wheel 31 and the secondary grinding stone 32 are arranged at positions facing each other across the axis Wa of the grinding object W, and the primary grinding wheel 31 is arranged in the second position. It is set at a position closer to the headstock 5 side in the X-axis direction than the grinding wheel 32 for next grinding. The primary grinding wheel 31 functions as a rough grinding wheel, and the secondary grinding wheel 32 functions as a finish grinding wheel. In FIG. 3, the grinding wheel 31 for primary grinding is omitted.

  The rotation holding unit 4 includes a chuck unit 41 that holds the end of the grinding target object W on the side opposite to the grinding, and a spindle unit 42 that rotationally drives the grinding target object W about its axis Wa.

  The headstock 5 includes a slide stage 52 that can be slid in the X-axis direction by a slide mechanism 51 (rail in the illustrated example) on the frame base 2, and a spindle that is fixed on the slide stage 52 and accommodates a spindle portion 42 therein. The base body 53 and an attachment base 54 for attaching the telescopic mechanism 6 to the headstock 5 so as to be detachable are integrally provided. In this embodiment, the attachment base 54 is attached to the headstock main body 53.

  The telescopic mechanism 6 is detachably attached to the head stock 5 and has a mounting part 61 on which one of the support parts 7 can be mounted at one end and a movable body 62 that can move in the X-axis direction, and an attachment member ( In the illustrated example, a holding portion 63 is provided that holds the movable body 62 movably in the X-axis direction while being attached to the attachment base 54 of the headstock 5 by screws S1). In the present embodiment, a plate-like member that is longer in the X-axis direction than the headstock body 53 is applied as the attachment base 54, and the cylindrical holding parts 63 are attached to both ends in the X-axis direction of the attachment base 54. Yes. And it is comprised so that the expansion-contraction mechanism 6 can be removed from the head stock 5 by canceling | releasing the attachment state of the holding | maintenance part 63 with respect to the attachment base 54 via attachment member S1.

The movable body 62 is configured by using, for example, a single columnar member extending in the X-axis direction, and is movable while being slid in the X-axis direction while being held by the holding portion 63, and the movable body main body. 64 integrally provided with a mounting portion 61 provided at one end portion of 64 and a flange portion 65 provided at the other end portion of the movable body main body 64 to prevent the movable body 62 itself from being detached from the holding portion 63. It is. The mounting portion 61 is provided with a first mounting portion 611 on which a support main body portion 71 constituting the supporting portion 7 described below is mounted and a second mounting portion 612 on which a pressing portion 72 is mounted on a common mounting base 613. Have a configuration. Further, in the present embodiment, the expansion / contraction operation of the expansion / contraction mechanism 6 that expands / contracts the distance between the headstock 5 along the X-axis direction and the support point of the workpiece W by the support portion 7 is interlocked with the forward movement of the headstock 5. In addition, the telescopic mechanism 6 can be expanded and contracted without being interlocked with the forward movement of the head stock 5, that is, in a state where the head stock 5 is stopped. In the following description, “distance between support point and headstock 5” is synonymous with “distance between support point and chuck portion 41”.

  The support part 7 includes a pair of support main body parts 71 that support the outer peripheral surface of the grinding object W from below at points different from each other in the circumferential direction, and the axial center of the grinding object W from above the outer peripheral surface of the grinding object W. And a pressing portion 72 that presses toward Wa. FIG. 1 shows a state before the second mounting portion 612 is attached to the mounting base 613.

  Each support main body 71 supports, for example, the outer surface of the grinding object W from obliquely below, and in this embodiment, the front end 711 of each support main body 71 (part contacting the grinding object W). Sintered diamond (not shown) is provided. In addition, the grinding machine 1 according to the present embodiment is configured so that the distance between the tip portions 711 of the pair of support main body portions 71 can be adjusted. Specifically, as shown in FIGS. 2 and 3, each support main body 71 is slidably mounted on an inclined surface 611a of the first mounting portion 611 that forms a predetermined angle with respect to the horizontal direction. By sliding the support main body portions 71 in directions toward or away from each other, the separation distance between the tip portions 711 of the pair of support main body portions 71 can be adjusted. In the present embodiment, a pair of first guide portions 611 g that guide the movement of the support main body portion 71 is formed on each inclined surface 611 a of the first mounting portion 611. And the grinding machine 1 of this embodiment can maintain the separation distance of the front-end | tip parts 711 of the support main-body part 71 at the arbitrary value by fixing each support main-body part 71 in arbitrary positions. Yes. As an aspect for fixing each support main body 71 at an arbitrary position, in this embodiment, each support main body 71 is formed with a long hole 71h into which the screw S2 can be inserted, and the screw S2 is passed through the long hole 71h from above. A mode of being screwed into a screw hole (not shown) provided in the first mounting portion 611 is employed. With such an aspect, the support body 71 can be slid within the longitudinal dimension of the long hole 71h with the screw S2 and the screw hole loosened, and the screw S2 can be moved at an arbitrary position. By tightening, the support main body 71 can be fixed at an arbitrary position.

  The pressing portion 72 presses, for example, the outer surface of the grinding object W from directly above, and in this embodiment, a sintered diamond (illustrated) is applied to the tip portion 721 of the pressing portion 72 (the portion that contacts the grinding object W). (Omitted). Further, the grinding machine 1 according to the present embodiment is configured such that the height position of the tip end portion 721 of the pressing portion 72 can be adjusted. Specifically, as shown in FIGS. 3 and 4, the pressing portion 72 is slidably attached to a hanging portion 612 a extending in the vertical direction in the second mounting portion 612, and the pressing portion 72 is moved in the height direction. By sliding, the height position of the tip end portion 721 of the pressing portion 72 with respect to the axis Wa of the grinding object W can be adjusted. In the present embodiment, the second guide portion 612g that guides the movement of the pressing portion 72 is formed on the surface of the hanging portion 612a that faces the grindstone 31, 32. And the grinding machine 1 of this embodiment can maintain the height position of the front-end | tip part 721 of the press part 72 in arbitrary positions by fixing the press part 72 in arbitrary positions. As an aspect for fixing the pressing portion 72 at an arbitrary position, in the present embodiment, a long hole 72h extending in the height direction in which the screw S3 can be inserted is formed in the pressing portion 72, and the second hole 72h is inserted into the second hole 72h through the screw S3. A mode is employed in which a screw hole (not shown) provided in the mounting portion 612 (the hanging portion 612a) is screwed. With such an aspect, the pressing portion 72 can be slid within the longitudinal dimension of the long hole 72h with the screw S3 and the screw hole loosened, and the screw S3 is tightened at an arbitrary position. Thus, the pressing portion 72 can be fixed at an arbitrary position.

  And in the grinding machine 1 of this embodiment, as shown in FIG. 4, two points where the front-end | tip part 711 of each support main-body part 71 contacts the outer surface of the grinding | polishing target object W, and the front-end | tip part 721 of the press part 72 are included. A total of three points, which are in contact with the outer surface of the object to be ground W, are set so as to be positioned at equal intervals or substantially equal intervals in the circumferential direction. That is, in the present embodiment in which the tip portion 721 of the pressing portion 72 is configured to contact the outer surface of the grinding target object W in the vertical direction, the tip of the pressing portion 72 is in contact with the tip portion 721 being ground. The position of the workpiece W that is 120 degrees clockwise is the contact position by the tip portion 711 of one support main body portion 71, and the circumferential direction of the workpiece W from the point that the tip portion 721 of the pressing portion 72 is in contact. The position distant 120 degrees counterclockwise is set to be the contact position by the tip 711 of the other support main body 71. Some angle error is allowed.

  Further, the grinding machine 1 of the present embodiment has a part of the mounting portion 61, specifically, the first mounting portion, at a position closer to the headstock 5 side than the grindstones 31 and 32 on the upward surface 21 of the frame base 2. A stopper 8 capable of coming into contact with 611 is attached. Note that the height position of the upper end of the stopper 8 is set to a position lower than the support main body portion 71 mounted on the first mounting portion 611, and the stopper 8 comes into contact with the grinding object W supported by the support portion 7. It is set so as not to be obtained (see FIGS. 2 and 4).

  Next, the usage method and operation of the grinding machine 1 according to this embodiment having such a configuration will be described.

  First, the end (base end) of the grinding object W on the side opposite to the grinding is held by the chuck part 41 of the rotation holding part 4, and the grinding object W is manually shaken out. Next, the position of the mounting portion 61 is adjusted by the telescopic mechanism 6 so that the grinding object W can be supported by the support portion 7. Then, a portion closer to the head stock 5 side than the position closest to the tip side (grinding processing start position) in the portion to be ground in the grinding object W is supported by the support portion 7. Specifically, according to the diameter of the grinding object W that can be grasped before the grinding process, the pressing part 72 is moved upward to a position where the tip 721 of the pressing part 72 does not interfere with the grinding object W in advance. The separation distance between the front end portions 711 of the support main body portion 71 is adjusted to an appropriate value. In this state, the grinding object W is placed on the pair of support main bodies 71, and the tip 711 of the support main body 71 is finely adjusted so that the grinding object W is stabilized. Then, the front-end | tip parts 711 of these pair of support main-body parts 71 contact | abut to the outer peripheral surface of the grinding target object W from diagonally downward, respectively, and can support the grinding target object W in the stable state. When the pressing portion 72 is lowered to a position where the tip end portion 721 contacts the outer peripheral surface of the grinding target object W, the grinding target object W supported by the pair of support main body portions 71 is moved to the tip end portion 721 of the pressing portion 72. Can be pressed from above. Thereby, it becomes a three-point support structure which supports the position which is different in the peripheral direction in the outer peripheral surface of grinding object W with each tip part 711, 721 of a pair of support main-body parts 71 and press part 72, and stabilized grinding object W It can be supported in a state. When the grinding object is supported by the support portion 7, each grinding wheel (the primary grinding wheel 31 and the secondary grinding wheel 32) is kept waiting at a position where it cannot contact the grinding object.

  Next, the grinding machine 1 of the present embodiment moves the primary grinding wheel 31 and the secondary grinding wheel 32 in the Y-axis direction to a position suitable for grinding while rotationally driving, and at the same time, the rotation holding unit 4. The spindle head 5 is moved (advanced) in the direction approaching the grindstones 31 and 32 along the X-axis direction while rotating the grinding object W. As the head stock 5 moves forward, the telescopic mechanism 6 attached to the head stock 5 moves in the same direction as the head stock 5. However, when the mounting portion 61 of the telescopic mechanism 6 contacts the stopper 8, Of these, the movement (advance movement) in the same direction of the mounting portion 61 and the movable body 62 integrally having the mounting portion 61 at the tip is restricted. On the other hand, the holding part 63 attached to the headstock 5 of the telescopic mechanism 6 holds the movable body 62 so as to be slidable, and moves integrally with the headstock 5. Due to the operation of the telescopic mechanism 6, the distance between the headstock 5 and the support point (support portion 7) gradually decreases as the headstock 5 moves forward, and passes through the support point in the grinding object W. Then, the primary grinding process (rough grinding process) with the primary grinding wheel 31 and the secondary grinding wheel 32 with respect to the part moved to the grinding wheel (primary grinding wheel 31, secondary grinding wheel 32) side. The next grinding process (finish grinding process) can be performed.

Here, as described above, the grinding machine 1 of the present embodiment moves the head stock 5 forward, rotates each grindstone (the grinding wheel 31 for primary grinding, the grinding wheel 32 for secondary grinding), and moves in the Y-axis direction. And simultaneously. That is, while the headstock 5 is moved forward, rough grinding is performed by the primary grinding wheel 31 disposed closer to the headstock 5 side than the secondary grinding wheel 32, and the secondary grinding wheel 32. To finish grinding. At that time, the secondary grinding stone 32 is to function as a presser for pressing the tip side of the grinding object W, can grind the object W takes appropriate grinding even those small diameter long . Further, by performing the forward movement of the headstock 5 and the rotation driving of each grindstone (the primary grinding grindstone 31 and the secondary grinding grindstone 32) and the movement in the Y-axis direction simultaneously, the processing by the primary grinding grindstone 31 is performed. Compared with the case where the secondary grinding wheel 32 is not operated at the time of processing and the processing is performed by the secondary grinding wheel 32 in a state where the operation of the primary grinding wheel 31 is stopped after the processing by the primary grinding wheel 31 is completed. Thus, it is possible to reduce the entire processing time by each grindstone (the primary grinding grindstone 31 and the secondary grinding grindstone 32) without causing a decrease in machining accuracy. It should be noted that the movement of the headstock 5 in the X-axis direction, the rotational driving of the grindstones 31 and 32 and the movement in the Y-axis direction can be performed either automatically or manually by a control unit (not shown). doing. When the movement of the headstock 5 in the X-axis direction, the rotational driving of the grindstones 31 and 32, and the movement in the Y-axis direction are automatically controlled, a control unit that controls the operation of the headstock 5 and the grindstones 31 and 32 The control unit for controlling the operation of the above can be realized by a single CPU (single core), or can be realized by separate CPUs (dual core).

  Further, the grinding machine 1 of the present embodiment is a portion of the rotating grinding object W that is exposed from the headstock 5 and is close to the grindstone (the primary grinding grindstone 31 and the secondary grinding grindstone 32). Since the outer surface is supported at three points different in the circumferential direction by the support portion 7, the grinding object W can be supported in a stable state. In particular, since the grinding machine 1 of the present embodiment can keep pressing the grinding object W from above with a linear constant pressure by the pressing portion 72, for example, the grinding object W is pressed from above with a pressure roller. Since there is no phenomenon that can occur as long as it is an aspect, that is, the chatter phenomenon of the grinding object W that occurs due to the “spinning” phenomenon in which the pressure roller rotates together with the rotation of the grinding object W, the accompanying phenomenon does not occur. Preventing and suppressing the problem that the grinding object W cannot be supported in a stable state due to the rotation and the processing accuracy by the grindstone is reduced, and stable machining by the grindstones 31 and 32 is performed with high accuracy. Can do. In addition, by imparting a spring function to the pressing portion 72, the outer surface of the grinding target object W that rotates the front end 721 of the pressing portion 72 is formed regardless of whether the grinding target object W has a perfect circular cross section. It can be pressed and pressed while always in contact. As a mode of giving a spring function to the pressing part 72, a mode of directly giving a spring function to the pressing part 72 itself, or a part of the telescopic mechanism 6 on which the pressing part 72 is mounted (the hanging part 612a of the second mounting part 612). In addition, slits notched in one direction along the Y-axis direction and slits notched in the other direction along the Y-axis direction are alternately formed in the height direction to give elasticity (not shown), The aspect which provides a spring function indirectly to the press part 72 attached to this mounting part 61 can be mentioned.

  Further, the grinding machine 1 of the present embodiment attaches sintered diamond to the tip portions 711 and 721 of the pair of support main body portions 71 and the pressing portion 72 constituting the support portion 7, and the sintered diamond is ground. Since the grinding object W is supported while being in contact with the outer surface of the object W, it is possible to effectively suppress wear / damage of the portion directly supporting the rotating grinding object W. .

  Furthermore, the grinding machine 1 according to the present embodiment is configured to be able to change the separation distance between the tip portions 711 of the pair of support main body portions 71 and to be able to change the height position of the tip portion 721 of the pressing portion 72. Therefore, even if it is a grinding object with different outer diameters and cross-sectional shapes, the distance between the tip portions 711 of the pair of support main body portions 71 and the pressing portion according to the outer diameter and cross-sectional shape of each grinding object. By appropriately changing the height position of the distal end portion 721 of 72, the distal end portion 711 of the pair of support main body portions 71 and the distal end portion 721 of the pressing portion 72 are appropriately supported in a state of being in contact with the outer surface of the object to be ground. Can do.

As described above, the grinding machine 1 according to the present embodiment exhibits the various functions and effects described above, and also sets the distance between the headstock 5 along the X-axis direction and the support point of the object to be ground W by the support portion 7. The object to be ground is defined by the position of the support portion 7 mounted on a part of the expansion / contraction mechanism 6 because the expansion / contraction operation of the expansion / contraction mechanism 6 can be performed independently of the forward movement of the headstock 5. The support point of W can be set at an arbitrary position independently of the forward movement of the headstock 5. That is, the grinding machine 1 shown in FIGS. 2 to 4 includes the mounting portion 61 of the expansion / contraction mechanism 6 because the mounting portion 61 that is a part of the expansion / contraction mechanism 6 is in contact with the stopper 8 fixed to the frame base 2. Further movement of the movable body 62 toward the grindstones 31, 32 is restricted, and the distance between the support point (support portion 7) and the headstock 5 becomes shorter as the headstock 5 moves forward. On the other hand, in this state (a state where the mounting portion 61 is in contact with the stopper 8 fixed to the frame base 2), the entire movable body 62 including the mounting portion 61 of the telescopic mechanism 6 is manually or automatically controlled to the headstock 5 side. It is possible to move by.

  Therefore, a portion of the grinding object W that can be supported by the support portion 7 in a state where the mounting portion 61 is in contact with the stopper 8 fixed to the frame base 2 is processed, for example, with a screw or a recess. When it is difficult to obtain a good support state by the support portion 7 due to the unique shape, the entire movable body 62 including the mounting portion 61 of the expansion / contraction mechanism 6 is moved to the headstock 5 side to support the main point and the main shaft. By reducing the distance from the base 5, a portion of the object to be ground W that can obtain a good support state (a portion that has not been processed such as a screw or a recess, or a portion having a circular or substantially circular cross section) ) Support points can be set.

  Moreover, since the grinding machine 1 which concerns on this embodiment has attached the expansion-contraction mechanism 6 with respect to the head stock 5 so that attachment or detachment is possible, the grinding | polishing target object does not need to be supported by the support part 7, for example, a diameter is from predetermined value. In the case of a grinding object having a larger length or a shorter grinding object whose longitudinal dimension is smaller than a predetermined value, grinding is performed while moving the headstock 5 with the telescopic mechanism 6 removed from the headstock 5. The object can be rotated and the object to be ground can be ground by the rotation of the grindstones 31 and 32. As described above, the grinding machine 1 of the present embodiment is suitable for grinding not only the grinding target W having a minimum diameter as shown in FIG. 1 but also the grinding target having a relatively large diameter. It is excellent in versatility and practicality.

  In addition, this invention is not limited to embodiment mentioned above. For example, the front end portions of the pair of support main body portions 71 constituting the support portion 7 and the front end portion 721 of the pressing portion 72 come into contact with each other at a position spaced apart at equal intervals (120 degrees each) in the circumferential direction of the grinding object W. Although the aspect set so that it may be obtained was illustrated, it can also set so that each front-end | tip part may contact a grinding | polishing target object in the circumferential direction of a grinding | polishing target object at a non-uniform space | interval.

  Moreover, it is possible to apply what was comprised using the ball screw mechanism as an expansion-contraction mechanism. The expansion / contraction mechanism is configured using a synchronous motor that synchronizes (extends / contracts) the distance between the headstock and the support point in accordance with the movement of the headstock, and is independent of the movement of the headstock. Thus, it may be configured using a single motor that expands and contracts the distance between the headstock and the support point.

  Moreover, it is good also as controllable by automatic control of the movement of the support main-body part and press part which comprise a support part. Furthermore, in the above-described embodiment, the movement direction of each support body portion is set to the normal direction passing through the axis of the object to be ground, but the movement direction of each support body portion is a direction other than the normal direction, for example, horizontal. Setting the direction is also conceivable. Further, only the distance between the tip portions of the pair of support main body portions constituting the support portion can be changed, and the height position of the tip portion of the pressing portion cannot be changed (fixed).

  Moreover, in the above-mentioned embodiment, although the aspect which supports the outer surface of a grinding target object in three places which differ in the circumferential direction was illustrated as a support part, for example, the number of a support main body part and a press part is increased / decreased suitably. For example, a configuration in which the outer surface of the object to be ground is supported at two or less places or at four or more places may be employed. Moreover, you may support a grinding target object in the state which the support part made the line contact or surface contact to the outer surface of the grinding target object.

  Moreover, you may be a grinding machine provided with only one grindstone. Furthermore, as the grindstone, not only the grindstone for grinding the outer surface of the object to be ground but also the grindstone for inner grinding that grinds the inner surface of the object to be ground may be used. Further, the grindstone may be movable only in the Y-axis direction and may not be movable in the X-axis direction. In particular, when the grindstone is an internal grinding grindstone, it is preferable that the grindstone is configured to be slidable in the X-axis direction.

  In addition, the specific configuration of each part is not limited to the above embodiment, and various modifications can be made without departing from the spirit of the present invention.

DESCRIPTION OF SYMBOLS 1 ... Grinding machine 2 ... Frame base 31 ... Grinding wheel for primary grinding 32 ... Grinding wheel for secondary grinding 4 ... Rotation holding part 5 ... Spindle base 6 ... Telescopic mechanism 7 ... Supporting part 71 ... Supporting body part 72 ... Pressing part W ... Grinding Object

Claims (5)

A grinder that grinds a rod-shaped grinding object by rotation of a grindstone provided on a frame base,
A rotation holding unit including a chuck unit that holds an end of the grinding object on the side opposite to the grinding side , and a spindle unit that drives the entire grinding object together with the chuck unit around its axis ; and A headstock mounted on the frame base so as to be movable in the axial direction of the grinding object;
A movable body main body that extends parallel to the axial direction of the object to be ground and is movable in the axial direction, and is detachably attached to the headstock , and the movable body main body is movable in the axial direction. It has a holding portion for holding the said a manner to stretch with the distance between the supporting point and the chuck portion for supporting the portion not held by the chuck portion to the movement of the headstock of the grinding object A telescopic mechanism capable of selecting a mode in which the distance between the support point and the chuck portion is expanded and contracted independently of the movement of the headstock ;
A support portion attached to an end portion on the grinding side of the movable body main body and supporting a portion on the headstock side as the support point with respect to the grindstone in the vicinity of the grindstone of the grinding object ;
A stopper provided on the frame base and restricting movement of the movable body main body toward the grindstone ;
The grinding object side along the axial direction of the grinding object in a state where the grinding object is supported at the support point by the support part and movement of the movable body main body to the grinding stone side is restricted by the stopper. With the movement of the headstock approaching gradually, the grindstone can grind the portion of the grinding object closer to the grindstone than the support point while gradually decreasing the distance between the chuck portion and the support point. A grinding machine characterized in that it is configured as follows.
Wherein the support unit includes a pair of support body portion for supporting the outer peripheral surface at mutually different points from below the circumferential direction of the grinding object, the axis of the grinding object the outer peripheral surface from above the grinding object The grinding machine according to claim 1, further comprising a pressing portion that presses toward the surface.
The grinding machine according to claim 2, wherein at least a separation distance between tip portions of the pair of support main body portions is adjustable. The grinding according to claim 2 or 3, wherein a sintered diamond is attached to each of the support main body portions at a tip portion that comes into contact with the object to be ground and each tip portion of the pressing portion that comes into contact with the object to be ground. Board. The grindstone includes a primary grinding grindstone that performs primary grinding and a secondary grinding grindstone that performs secondary grinding, and each of these grindstones is spaced apart in the axial direction of the grinding object. It is movable in a direction orthogonal to the center direction, and each of these grindstones simultaneously moves in the direction of sandwiching the object to be ground and the headstock moves toward the grindstone side along the axis direction. The grinding machine according to any one of claims 1 to 4, wherein primary grinding and secondary grinding are performed with a rotating grindstone.

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