JP2009202309A - Chuck - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a chuck capable of opening/closing a member corresponding to a claw receiving base without applying tensile force to a part for converting the movement of a center shaft direction into the movement of a holding claw orthogonal to this movement, and suppressing lowering of holding force due to centrifugal force in high speed rotation, even if a balance weight unnecessary in a function for holding a chuck originally machining object is not provided. <P>SOLUTION: This chuck includes a first slider which freely advances/retreats in a radiation direction orthogonal to a center shaft of the chuck and is mounted with the holding claw for holding the machining object, a second slider which freely advances/retreats in the radiation direction and moves in the opposite direction of the first slider, a driving means which freely advances/retreats in a center shaft direction and moves one of the first or second sliders to the outside or inside of the radiation direction by pressing and moving the one slider, and a direction conversion and transmission means for converting the direction of the movement of the one slider to the opposite direction and transmitting the movement to the other slider. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a chuck that grips a workpiece with a plurality of gripping claws during machining such as cutting.

  As such a chuck, a wedge-type chuck is well known. As an example, a wedge type chuck described in Patent Document 1 below can be cited.

  In the case of the wedge-type chuck described in Patent Document 1, the movement of the gradient sleeve in the chuck rotation center axis direction is changed to the movement of the nail cradle orthogonal thereto, and the claw cradle is opened and closed, and attached to the claw cradle. Hold the object to be processed with the gripping claws. As a structure for this purpose, one of the engaging portions of the gradient sleeve and the claw cradle is formed in a T-shaped cross section on the one hand and a substantially C-shaped cross section on the other side. Part) is slidably embraced so as to fit together.

  Conventionally, when the chuck is rotated at a high speed, a centrifugal force caused by the rotation acts on the gripping claws and the claw cradle, and thus a problem has been pointed out that the gripping force for gripping the workpiece is reduced.

  The chuck described in Patent Document 1 also shows a solution to such a problem. In the case of the chuck described in Patent Document 1, when the chuck is rotated at a high speed, a balance weight is provided for alleviating the centrifugal force acting on the gripping claw and the claw cradle by the rotation. In other words, a weight support is installed on the opposite side of the claw support with the rotation center axis of the chuck, and the nail support and the weight support are connected with a connecting rod, and a balance weight is attached to the weight support. It can be done.

  When the chuck rotates at a high speed, centrifugal force in the direction opposite to the centrifugal force acting on the gripping claw and claw cradle acts on the balance weight and the weight cradle due to the centrifugal force caused by the rotation. Centrifugal force acting on the cradle is offset, and a decrease in gripping force with which the gripping claws grip the workpiece is suppressed.

JP-A-7-51908

  However, in the general wedge-type chuck described above, a thin-walled portion such as a T-shaped cross-section or a C-shaped cross-section must be formed in the engaging portion between the gradient sleeve and the claw base due to the structure. When a large tensile load is applied to the thin portion, there is a problem that the thin portion is likely to break.

  Further, in order to cancel the centrifugal force acting on the gripping claw and the claw cradle, a member such as a balance weight that is unnecessary in terms of the function of gripping the original workpiece to be chucked must be provided. However, there is a problem that the weight of the chuck is increased.

  Therefore, in view of the above-described circumstances, the present invention eliminates the need to form a thin portion in a portion that converts the movement of the gradient sleeve into the movement of the gripping claw that is orthogonal thereto, and is a member corresponding to the gradient sleeve. The first object is to provide a chuck having a novel structure capable of opening and closing (advancing and retreating) a member corresponding to the claw cradle without applying a tensile force between the members corresponding to the claw cradle and the claw cradle. Yes.

  Furthermore, in addition to the above-mentioned purpose, when the chuck is rotated around the central axis, the centrifugal force during high-speed rotation can be reduced without providing a member unnecessary for the function of gripping the original workpiece to be chucked. A second object is to provide a chuck capable of suppressing a decrease in gripping force for gripping a workpiece by influence.

  In order to achieve the above-mentioned object, the chuck according to the present invention can be moved forward and backward in the radiation direction perpendicular to the central axis of the chuck, and can be moved forward and backward in the same radial direction as the first slider to which a gripping claw for gripping a workpiece is attached. A second slider that freely moves in the direction opposite to the first slider, and one of the first and second sliders that can move forward and backward in the direction of the central axis and move one of the sliders outward in the radiation direction or It is characterized by comprising driving means for moving inward and direction change transmitting means for converting the movement of one slider to the opposite direction and transmitting it to the other slider.

  With such a feature, the chuck according to the present invention has a structure in which one of the first slider and the second slider is pushed by the driving means when the workpiece is gripped or released. Therefore, there is no need to form a thin portion in the portion that changes the movement of the driving means in the central axis direction to the movement of the gripping claws orthogonal to each other, and the driving means corresponding to the gradient sleeve and the first slider corresponding to the claw cradle The first slider can be advanced and retracted without applying a tensile force between each other or with the second slider. As described above, since the thin-walled portion where the failure such as breakage is likely to occur is not provided in the structure, it is possible to provide a chuck having a robust structure in which the failure such as breakage is unlikely to occur.

  In addition to the above-described effects, when the chuck is rotated at high speed around the central axis, the centrifugal force acting on the second slider is changed to the opposite direction by the direction change transmission means and transmitted to the first slider. Therefore, the centrifugal force acting on the first slider functioning as a claw cradle and the gripping claw can be offset. Therefore, the gripping force for gripping the workpiece may be reduced due to the centrifugal force acting during high-speed rotation without the need for a functionally unnecessary member for gripping the chuck originally intended workpiece. It is possible to suppress the increase.

  Further, if the first slider, the second slider, the driving means, and the direction change transmission means arranged on the chuck are divided into a plurality of systems, and each system operates independently, When a workpiece is gripped by four (two to two systems) gripping claws provided in the orthogonal direction, it becomes easy to position and grip the center of the workpiece on the central axis of the chuck.

  Further, a counterweight whose total weight with the second slider is equal to the total weight of the first slider and the gripping claws is detachably attached to the outer end portion of the second slider, so that the gripping claws are attached to the weight of the second slider. The centrifugal force acting on the replaced gripping claw can be accurately canceled without disassembling the chuck each time it is replaced with a different one.

  Embodiments of a chuck according to the present invention will be described below with reference to FIGS.

  1 to 3 show an embodiment of a chuck according to the present invention, in which FIG. 1 is a perspective view showing the appearance of the chuck, and FIG. 2 is a part shown by removing a front cover of the chuck and partially breaking it. FIG. 3 is a cutaway perspective view, and FIG. 3 is a cross-sectional view taken along line AA of FIG.

  The chucks shown in these drawings grip a workpiece (not shown) by a plurality of gripping claws (not shown) arranged around the rotation center axis 0 and rotate around the rotation center axis 0 of the chuck. The gripping claw is attached to the first slider 1 that can advance and retract in the radiation direction orthogonal to the rotation center axis 0. For attaching the gripping claw to the first slider 1, for example, a screw hole 1 a into which a bolt is screwed is provided on the upper surface of the first slider 1, and a bolt that penetrates the root of the gripping claw is provided in the screw hole 1 a. This is done by screwing and tightening.

  Three first sliders 1 are provided radially at equal angular intervals around the rotation center axis 0 (in the drawing, only one is shown for the sake of easy viewing). Each first slider 1 is disposed in guide grooves 3 a and 5 a provided in the chuck housing 3 and the front cover 5. The guide grooves 3a and 5a are provided radially at equiangular intervals around the rotation center axis 0, respectively. Accordingly, each of the first sliders 1 is guided by the guide grooves 3a and 5a and slides so as to be able to advance and retract in the radiation direction orthogonal to the rotation center axis 0. The front cover 5 is fixed to the upper surface of the housing 3 by fixing means such as bolts.

  In each guide groove 3a, a second slider 2 is disposed below the first slider 1, and is guided by the guide groove 3a and slides freely in a radiation direction perpendicular to the rotation center axis 0. It is like that. In the figure, only one second slider 2 is shown with emphasis on the visibility of the figure.

  A downward slope 1b is formed at the inner end of the first slider 1 on the rotation center axis 0 side, and an upward slope 2b is formed at the inner end of the second slider 2 on the rotation center axis 0 side. Is formed. The inclined surfaces 1b and 2b are inclined at the same angle (for example, 45 degrees) symmetrically with respect to the surface where the sliders 1 and 2 contact each other.

  And between the slopes 1b and 2b, it arrange | positions so that a part of sleeve head 7 may be inserted | pinched. The sleeve head 7 is fixed to the tip of a cylindrical sleeve 8 provided at the center of the chuck so as to be able to advance and retreat along the rotation center axis 0. The sleeve head 7 is rotated together with the sleeve 8 by a power source such as a fluid pressure cylinder (not shown). It is driven so as to be able to advance and retreat in the extending direction. Surfaces 7a and 7b that contact the inclined surfaces 1b and 2b of the sliders 1 and 2 of the sleeve head 7 are constituted by conical outer surfaces inclined corresponding to the inclinations of the inclined surfaces 1b and 2b.

  When the sleeve head 7 is pushed upward in the drawing, the first slider 1 is pushed and moved outward in the radiation direction. On the contrary, when the sleeve head 7 is pulled downward in the drawing, the second slider 2 is pushed and moved outward in the radiation direction. That is, the sleeve head 7 functions as a driving unit that pushes and moves the first or second slider 1 or 2 to move outward in the radiation direction.

  A downward slope 1 c is formed at the intermediate portion in the radial direction of the first slider 1, and an upward slope 2 c is formed at the intermediate portion in the radial direction of the second slider 2. The inclined surfaces 1c and 2c are also inclined at the same angle (for example, 45 degrees) symmetrically with respect to the surface where the sliders 1 and 2 contact each other. A cylindrical roller 10 is disposed between the inclined surfaces 1c and 2c. A block 11 is fixed to the housing 3 on the outside of the roller 10 by fixing means such as bolts, and the movement of the roller 10 outward in the radial direction is restricted.

  For this reason, when the sleeve head 7 is pulled down and the second slider 2 moves outward in the radial direction, the roller 10 receives pressure from the inclined surface 2 c and is pushed up along the side surface of the block 11. The roller 10 pushed up presses the inclined surface 1c of the first slider 1, and pushes the first slider 1 inward in the radiation direction.

  Conversely, when the sleeve head 7 is pushed up and the first slider 1 moves outward in the radial direction, the roller 10 receives pressure from the inclined surface 1 c and is pushed down along the side surface of the block 11. The pressed roller 10 presses the inclined surface 2c of the second slider 2, and pushes the second slider 2 inward in the radiation direction. That is, this roller 10 functions as a direction change transmission means for converting the movement of one slider 1 or 2 to the opposite direction and transmitting it to the other slider 2 or 1.

The first slider 1 and the second slider 2 are always moved in opposite directions by the action of the roller 10 functioning as the direction change transmission means.
By the way, it is also possible to form the inclined surfaces 1c and 2c at the radially outer ends of the first slider 1 and the second slider 2, respectively. However, this embodiment does not do so, and the reason why it is formed in the intermediate portion in the radiation direction is as follows.
That is, if the inclined surfaces 1c and 2c are formed at the radial outer ends of the first slider 1 and the second slider 2, respectively, the roller 10 and the block 11 must be further disposed outside the inclined surfaces 1c and 2c. The diameter will increase. This is to prevent the chuck from becoming unintentionally enlarged.

  Next, the operation of the chuck when gripping and releasing the workpiece will be described. When the gripping claws grip the workpiece from the outside, first, the sleeve head 7 is pulled down, and the second slider 2 is pushed outward in the radiation direction. Then, the roller 10 is pushed up by the second slider 2, and the first slider 1 is moved inward in the radiation direction. As a result, the gripping claws attached to the first slider 1 narrow the distance from the rotation center axis 0, and the workpiece is gripped inside the three gripping claws.

  When releasing the workpiece to be gripped in this way, the sleeve head 7 is pushed up, and the first slider 1 is pushed outward in the radiation direction. The roller 10 is pushed down by the movement of the first slider 1 to move the second slider 2 inward in the radiation direction. As a result, the gripping claw attached to the first slider 1 increases the distance from the rotation center axis 0, and the workpiece to be gripped by the gripping claw is released.

  When the workpiece is a relatively large-diameter cylindrical object and the gripping claw grips the workpiece from the inside rather than from the outside, the gripping and releasing operations described above are reversed.

  As described above, according to the chuck of the first embodiment, when the workpiece is gripped or released, one of the first slider 1 and the second slider 2 is pushed by the sleeve head 7. Therefore, it is not necessary to form a thin part that is vulnerable to a large tensile load at the part that changes the movement of the rotation center axis direction to the movement of the gripping claw orthogonal to the conventional wedge type chuck, and it is an obstacle such as breakage It is possible to provide a chuck having a robust structure in which the occurrence of the occurrence of the problem is difficult.

  When the chuck rotates at high speed and centrifugal force acts on the first slider 1, the centrifugal force always acts on the second slider 2 at the same time, and the direction of the first slider 1 is changed by the roller 10. It is transmitted to. As a result, the centrifugal force acting on the first slider 1 is canceled out by the centrifugal force acting on the second slider 2, and the increase or decrease in the gripping force for gripping the object to be processed due to the centrifugal force is suppressed. it can.

  Moreover, unlike the prior art, it is unnecessary for the function of gripping the original workpiece to be chucked, and it is not necessary to provide a member such as a balance weight provided only to alleviate the influence of centrifugal force. The structure is not complicated and the weight is not increased.

  The total weight of the gripping claws and the first slider 1 and the weight of the second slider 2 are preferably adjusted in advance. This is because by adjusting the weights equally, the gripping force when the workpiece is gripped by the chuck in a stationary state can be maintained as it is even during high-speed rotation.

  Next, an embodiment different from the above-described embodiment 1 will be described with reference to FIGS. 4 is a partially broken perspective view in which the front cover of the chuck is removed and a part thereof is broken as in FIG. 2, and FIG. 5 is a longitudinal sectional view as seen from the same direction as FIG. In these drawings, members or portions common to those in the first embodiment are denoted by common reference numerals, and detailed description thereof is omitted.

  4 and 5 is the same as the first embodiment except that the shape of the sleeve head 7 and the counterweight W are different from those of the first embodiment.

  The sleeve head 7 of the first embodiment is shaped like an abacus bead, and the surfaces 7a and 7b that contact the inclined surfaces 1b and 2b of the first slider 1 and the second slider 2 are conical outer surfaces. It was. For this reason, when the sleeve head 7 comes into contact with the inclined surface 1b or 2b, line contact occurs, and the contact portion easily wears, and there is a risk of deformation when a large load is applied to the contact portion.

  On the other hand, in the case of the sleeve head 7 of the second embodiment, the surfaces 7a and 7b in contact with the inclined surfaces 1b and 2b of the first slider 1 and the second slider 2 are flat. For this reason, when the sleeve head 7 abuts against the inclined surface 1b or 2b, surface contact occurs, and therefore, the wear and deformation of the contact portion are less likely to occur than in the first embodiment.

  In the case of the first embodiment, in order to accurately cancel the influence of the centrifugal force acting on the gripping claws, the chuck is disassembled every time the gripping claws are replaced with gripping claws having different weights, and the second slider 2 is moved. It was necessary to replace the second slider 2 with a weight corresponding to the weight of the gripping claw. On the other hand, the second embodiment is provided with a counterweight W that is detachably attached to an outer end portion of the second slider 2 by an attaching means such as a bolt. The counterweight W is formed so that its cross section is smaller than the cross-sectional shape of the guide groove 3 a partitioned by the block 11 so that the outer open end of the guide groove 3 a formed in the housing 3 can pass therethrough. Accordingly, the counterweight W can be attached to and detached from the outer end of the second slider 2 through the outer open end of the guide groove 3a without disassembling the chuck.

The outer open end of the guide groove 3 a is provided in the housing 3 so as to face the outer end of the second slider 2, and functions as a through hole through which the counterweight W can be passed.
The weight of the counterweight W is set so that the total weight combined with the weight of the second slider 2 is equal to the total weight of the first slider 1 and the gripping claws (not shown) attached thereto.

  In general, a plurality of types of gripping claws are prepared so that an optimum gripping claw can be selected according to the shape of the workpiece, the method of machining, the type of cutting tool, and the like. Therefore, it is necessary to prepare a plurality of counter weights according to the weight of the gripping claws.

  The weight of the prepared counterweight W can be made equal to the weights of various gripping claws, or can be a weight obtained by subtracting the weight of the lightest gripping claws from the weights of various gripping claws. . In order to make them equal, the weights of the first slider 1 and the second slider 2 may be made to correspond to each other. When subtracting the weight of the lightest gripping claw, the weight of the lightest weight of all the prepared gripping claws is added to the weight of the second slider 2 in advance, and the counterweight W Is equal to the weight obtained by subtracting the weight of the lightest gripping claws from the weights of various gripping claws.

  When the weight of the lightest gripping claw is subtracted in this way, the weight of the counterweight W is reduced by that amount, and the centrifugal force acting on the counterweight W is also reduced. Therefore, a bolt or the like for attaching the counterweight W to the second slider 2 This is preferable because the burden of centrifugal force applied to the attachment means can be reduced.

  Counterweights corresponding to the weights of various gripping claws are prepared in advance, and when the gripping claws selected in consideration of the shape of the workpiece are attached to the first slider 1, the weights corresponding to the weights are set. By attaching the counterweight W to the outer end portion of the second slider 2, it is possible to accurately cancel the centrifugal force acting on the first slider 1 and the gripping claws.

  In addition, the replacement work of the counterweight W is very easy without disassembling the chuck because the counterweight W can be taken in and out through the outer open end of the guide groove 3a and can be attached to and detached from the second slider 2. Can be done.

  For ease of explanation, it has been described that the total weight of the second slider 2 and the counterweight W is set to be equal to the total weight of the first slider 1 and the gripping claws. The total weight includes the weight of attachment means such as bolts used to join each other.

  Next, an embodiment different from Embodiments 1 and 2 described above will be described with reference to FIG. FIG. 6 is a partially broken perspective view in which the front cover of the chuck is removed and a part thereof is broken. In the drawing, members or portions common to those in the first and second embodiments are denoted by common reference numerals, and detailed description thereof is omitted.

  In the chucks described as the first and second embodiments, three first sliders 1 are provided radially at equal angular intervals around the rotation center axis 0, and the operation is unified by the operation of a single sleeve head 7. It was the structure controlled by.

  On the other hand, in the case of the chuck according to the third embodiment, a total of four first sliders 1 are provided, two at a time so as to be paired with the rotation center shafts radially spaced at equal angular intervals around the rotation center shaft 0. Corresponding to these, four second sliders 2 and four rollers 10 are provided.

  The sleeve head 7 is divided into four parts, and the sleeve to which the sleeve head is fixed has a double structure in which two cylindrical sleeves having different diameters are stacked inside and outside. The inner sleeve 81 and the outer sleeve 82 are separately provided. Advancing and retreating along the rotation center axis 0 is possible.

  A pair of sleeve heads facing each other across the rotation center axis 0 among the sleeve heads divided into four are fixed to the tips of the inner sleeve 81 and the outer sleeve 82, respectively. For example, as illustrated, a pair of sleeve heads 71 is fixed to the tip of the inner sleeve 81, and another pair of sleeve heads 72 is fixed to the tip of the outer sleeve 82.

  As a result, it is possible to operate the first slider facing the rotation center axis 0 as an independent system for each sleeve independently of other systems. That is, in the case of the third embodiment, the first slider 1, the second slider 2, the drive means (sleeve heads 71 and 72) and the direction change transmission means (roller 10) sandwich the rotation center axis 0 of the chuck, respectively. Two systems are provided so as to be symmetrically paired, and each system is configured to operate independently.

  For example, if the system of the inner sleeve 81 is the first system and the system of the outer sleeve 82 is the second system, the first slider 1 of the first system is moved by the inner sleeve 81. The workpiece is gripped in the center between the gripping claws of the first system, and the second slider 1 is moved by the outer sleeve 82 to grip the workpiece in the center of the gripping claws of the second system. can do. In this way, when the four gripping claws are operated as one system, one gripping claw does not come into contact with the workpiece, and the problem of gripping the workpiece with only three gripping claws can be prevented. The center of the workpiece can be easily positioned on the rotation center axis of the chuck, and can be securely gripped by the four gripping claws.

  In addition, different gripping forces can be set for each system so that the workpiece can be gripped with different gripping forces for each system, and the gripped part of the workpiece to be gripped by the gripping claws is rotationally symmetrical If not, the workpiece can be reliably gripped by the four gripping claws.

  Next, an embodiment different from Embodiments 1 to 3 described above will be described with reference to FIGS. FIG. 7 is a perspective view showing the chuck with the front cover removed, and FIG. 8 is a plan view of the chuck shown in FIG. In the drawing, members or portions common to those in the first to third embodiments are denoted by common reference numerals, and detailed description thereof is omitted.

  In the chuck described as the third embodiment, the four first sliders 1 are divided into two systems and can be operated independently for each system.

  On the other hand, in the case of Example 4, one more system is added to form three systems. Accordingly, a total of six first sliders 1 are provided so as to be paired with the rotation center axis sandwiched radially around the rotation center axis 0 at equal angular intervals. Two and six rollers 10 are also provided.

  The sleeve head 7 is divided into six parts, and the sleeve to which the sleeve head is fixed has a triple structure in which three cylindrical sleeves having different diameters are sequentially stacked. An inner sleeve 81, an outer sleeve 82, and an intermediate sleeve 83 are Each can be advanced and retracted along the rotation center axis 0 separately.

  A pair of sleeve heads facing each other across the rotation center axis 0 among the sleeve heads divided into six are fixed to the tips of the inner sleeve 81, the outer sleeve 82, and the middle sleeve 83, respectively. For example, as illustrated, a pair of sleeve heads 71 is fixed to the tip of the inner sleeve 81, a pair of sleeve heads 72 is fixed to the tip of the outer sleeve 82, and a pair of sleeve heads 73 is fixed to the tip of the intermediate sleeve 83. Is fixed.

  In the case of the fourth embodiment as well, as in the case of the third embodiment, the first slider facing the rotation center shaft 0 as an independent system for each sleeve is operated independently of the other systems. Is possible.

Since it has such a structure, for example, the object to be processed can be gripped by gripping claws that operate for each system, and the number of gripping nails increases as the number of systems increases, so the object to be processed is gripped. It is possible to distribute the gripping force to more gripping claws.
In the fourth embodiment, the six gripping claws are divided into three systems, but it is also possible to divide the two gripping claws into two systems and open and close the three gripping claws separately for each system.

  Next, an embodiment different from the above-described Embodiments 1 to 4 will be described with reference to FIG. FIG. 9 is a longitudinal sectional view of the chuck. In the drawing, members or portions common to those in the first to fourth embodiments are denoted by common reference numerals, and detailed description thereof is omitted.

  In this embodiment, a cylindrical roller 10 is used as the direction change transmission means for converting the movement of the first slider or the second slider to the opposite direction and transmitting it to the other slider in the first to fourth embodiments. On the other hand, the main difference is that a lever 13 that swings around the support shaft 12 is used.

  The lever 13 is rotatably supported by a support shaft 12 provided between the first slider 1 and the second slider 2 that are spaced apart from each other, and swings about the support shaft 12. The ends of the first slider 1 and the second slider 2 are in contact with both ends of the lever 13.

  When the sleeve 8 pulls the sleeve head 7 downward in the drawing, the second slider 2 is pushed outward in the radial direction by this movement, and the lever 13 is swung. The movement of the second slider 2 is converted to the opposite direction by the swing of the lever 13, and is transmitted to the first slider 1, and the first slider 1 moves in the radial direction. Since the first slider 1 is attached with a gripping claw (not shown), the gripping claw narrows the mutual distance and grips the workpiece.

  Next, an embodiment different from the above-described embodiments 1 to 5 will be described with reference to FIG. FIG. 10 is a longitudinal sectional view of the chuck. In the drawing, members or portions common to those in the first to fifth embodiments are denoted by common reference numerals, and detailed description thereof is omitted.

  The sixth embodiment is a modification of the second embodiment shown in FIGS. 4 and 5, and the positions where the slopes 1c and 2c of the first slider 1 and the second slider 2 are formed are the positions of the sliders. The outer end of the. In addition, the outer sleeve head 15 is disposed between the inclined surfaces 1c and 2c, not the cylindrical roller 10 described in the second embodiment.

  The outer sleeve head 15 is fixed to the tip of a fork 16 extending in the direction of the rotation center axis 0 from a cylindrical outer sleeve (not shown) provided on the outer periphery of the chuck so as to be able to advance and retreat in the direction of the rotation center axis 0. Driven along with the outer sleeve by a power source such as a fluid pressure cylinder so as to be able to advance and retract in the direction of the rotation center axis 0

  The surfaces 15a and 15b of the outer sleeve 15 that are in contact with the inclined surfaces 1c and 2c of the sliders 1 and 2 are formed by inclined planes corresponding to the inclined surfaces of the inclined surfaces 1c and 2c.

  When the outer sleeve head 15 is pulled down in the drawing, the second slider 2 is pushed and moved inward in the radiation direction. Conversely, when the outer sleeve head 15 is pushed upward in the drawing, the first slider 1 is pushed and moved inward in the radiation direction. That is, in the sixth embodiment, the outer sleeve head 15 functions as a driving unit that pushes and moves the first or second slider 1 or 2 inward in the radiation direction.

  If the sleeve head 7 arranged at the center of the chuck is free and can move freely, when the outer sleeve head 15 is pulled down and the second slider 2 moves inward in the radial direction, the sleeve head 7 Receives pressure from the inclined surface 2b and is pushed up along the rotation center axis 0. The pushed-up sleeve head 7 presses the inclined surface 1b of the first slider 1, and pushes the first slider 1 outward in the radiation direction.

  Conversely, when the outer sleeve head 15 is pushed up and the first slider 1 moves inward in the radial direction, the sleeve head 7 receives pressure from the inclined surface 1b and is pushed down along the rotation center axis 0. The pushed-down sleeve head 7 presses the inclined surface 2b of the second slider 2 and pushes the second slider 2 outward in the radiation direction. In this case, the sleeve head 7 functions as direction change transmission means for converting the movement of one slider 1 or 2 to the opposite direction and transmitting it to the other slider 2 or 1.

  In the above description, the sleeve head 7 is described as being free. However, the first or second slider 1 or 2 may be moved by the sleeve head 7 positioned at the center of the chuck with the outer sleeve head 15 being free. Is possible. In this case, the sleeve head 7 functions as direction change transmission means for converting the movement of one slider 1 or 2 to the opposite slider 2 or 1 by converting the direction to the opposite direction.

  Further, even if the sleeve head 7 is driven in the direction opposite to the outer sleeve head 15, the operation is the same. In this case, it is not clear which sleeve head functions as the direction change transmission means, but it can be considered that the sleeve head having a weak thrust functions as the direction change transmission means.

  In each of the first to sixth embodiments described so far, the chuck has been described as rotating about the rotation center axis 0. However, in any of the embodiments, a stationary chuck that does not have a function of rotating may be used. It can be installed on a workbench or attached to the tip of a robot arm.

  By the way, the technical matters described in the respective embodiments can be rearranged unless they are technically contradictory. For example, the counterweight W is attached to the outer end portion of the second slider 2 described in the second embodiment. About a point, it is applicable to all the Examples except Example 6. The reason why it cannot be applied to the sixth embodiment is that it is difficult to secure a space for attaching the counterweight W because the outer sleeve head 15 is in contact with the outer end portion of the second slider 2.

  The chuck according to the present invention can be produced industrially and used industrially.

It is the perspective view which showed Example 1 of this invention. Example 1 It is a partially broken perspective view showing Example 1 of the present invention. Example 1 It is sectional drawing which showed the AA cross section of FIG. Example 1 It is a partially broken perspective view showing Example 2 of the present invention. (Example 2) It is the longitudinal cross-sectional view which showed Example 2 of this invention. (Example 2) It is the partially broken perspective view which showed Example 3 of this invention. (Example 3) It is the perspective view which showed Example 4 of this invention. (Example 4) FIG. 9 is a plan view of the fourth embodiment when viewed from the direction B in FIG. 8 (fourth embodiment). It is the longitudinal cross-sectional view which showed Example 5 of this invention. (Example 5) It is the longitudinal cross-sectional view which showed Example 6 of this invention. (Example 6)

Explanation of symbols

DESCRIPTION OF SYMBOLS 0 Rotation center shaft 1 1st slider 1a Screw hole 1b Slope 1c Slope 1e Engagement hole 2 2nd slider 2a Slope 2b Slope 3 Housing 3a Guide groove 5 Front cover 5a Guide groove 7 Sleeve head 8 Sleeve 10 Roller 11 Block 12 Support shaft 13 Lever 14 Bar-shaped member 15 Diaphragm 15a Claw base 15b Lever portion 71 Sleeve head 72 Sleeve head 73 Sleeve head 81 Sleeve 82 Sleeve 83 Sleeve

Claims (3)

A chuck for gripping a workpiece with a plurality of gripping claws arranged around a central axis,
A first slider to which the gripping claw is attached so as to be movable back and forth in a radiation direction perpendicular to the central axis
A second slider that is movable back and forth in the radiation direction and moves in the opposite direction to the first slider;
Drive means for moving forward and backward in the direction of the central axis and pushing one of the first or second sliders to move the one slider outward or inward in the radiation direction;
A chuck comprising: direction change transmission means for converting the movement of the one slider to the opposite direction and transmitting it to the other slider. The chuck according to claim 1,
A chuck characterized in that the first slider, the second slider, the driving means, and the direction change transmission means are provided for a plurality of systems, and each system operates independently. The chuck according to claim 1 or 2,
A housing that houses at least the second slider;
A counterweight that is detachably attached to the outer end of the second slider and has a total weight with the second slider equal to the total weight of the first slider and the gripping claws;
The chuck characterized in that the housing is provided with a through hole through which the counterweight can be passed, facing the outer end of the second slider.

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