JPH08174360A - Gear grasping device - Google Patents

Abstract

PURPOSE: To reduce the occurrence of a defective gear grasping sate owing to unevenness in shape precision and size precision of a gear by a method wherein a chuck claw engaged with a tooth groove is peripherally arranged at a nipping member in such a manner to be movable relatively with the nipping member. CONSTITUTION: When chuck claws 17a, 17b, 17c, and 17d are securely mounted at a nipping member, in a case the teeth of a gear 12 and the size and the shape of a tooth surface are adverse, the gear is moved along the chuck claws and there is a fear of core displacement occurring between the central axis of a pitch circle and a machining central and. In this case, since chuck claws 17a, 17b, 17c, and 17d are brought into a state to be movable relatively with clampers 14 and 15, even when a gear having low shape precision and size precision, the chuck claws 17a and 17b are slid over the upper clamper 14 and the chuck claws 17c and 17d over the lower clamper 15 to a position where gear grasping is most stabilized. This constitution prevents the occurrence of a core displacement between a pitch circle central axis and a machining central axis.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gear gripping device required for machining an article having a tooth surface such as a gear, in which a gear is gripped by the tooth surface of the gear. The present invention relates to the gear gripping device.

[0002]

2. Description of the Related Art Conventionally, for gears, the actual construction of Sho 63-1
As disclosed in Japanese Patent Publication No. 86534, a gear is gripped by its tooth tip surface with a V bevel interlocking with the outer periphery of the gear, and then cutting such as gear center drilling is performed.

However, for a gear having low roundness or cylindricity of the addendum circle, addendum cylindricity, or addendum circle diameter, for example, formed by hot or cold forging, the addendum of the addendum is small. When cutting such as drilling a gear center while the surface is gripped by the V bevel, the tooth top surface of the gear may not properly contact the V bevel. In other words, an incomplete gripping state in which the gear is gripped while tilted, or an insufficient gripping state in which the gripping force is not transmitted sufficiently and the gear slides during machining, causing chatter vibration, etc. during machining. Therefore, the machining accuracy of the gear is reduced.

When the gear thus processed is actually used as a component, the concentricity between the center of the gear center hole, which is the center of rotation of the gear, and the center of the gear pitch circle where the gears mesh with each other, and the center axis of the gear center hole, Since the parallelism with the center axis of the gear pitch circle is reduced, the gears are loosely engaged with each other.

[0005]

In order to solve this play, it is necessary to grip the gear with the tooth flanks of the gears and perform gear center hole machining with reference to the tooth flanks where the gears actually mesh. Conceivable. As shown in FIG. 5, in order to hold the gear on the tooth flank of the gear, a fixed claw 22 meshes with the tooth groove of the gear.
V bevel 23a having a, 22b, 22c, 22d,
It is conceivable to use a holding member such as 23b.

However, in gripping with the V-bevel with the fixed claw, the fixed position of the fixed claw is fixed in advance so that the fixed claw meshes with the tooth space of the gear having a size and shape designed. Therefore, for example, due to manufacturing errors, tooth profile of the gear, tooth surface shape, tooth groove shape, gear pitch circle diameter roundness, tooth surface dimension,
When gripping a gear having slightly different shapes and dimensions such as the tooth groove size and the gear pitch circle diameter dimension, the fixed claw cannot accurately mesh with the tooth groove of the gear having the dimension and shape determined by design. In other words, since the gear is gripped in an unreasonable state, the gear is gripped in a distorted state with respect to the sandwiching member and the fixed claw, the center axis of the gear pitch circle and the machining axis are deviated, and the machining accuracy decreases. I will end up.

The present invention has been made to solve the above-mentioned problems, and a claw that meshes with a tooth groove is provided movably in the gear circumferential direction with respect to the holding member, so that the tooth groove of the claw and the gear can be formed. The object of the present invention is to make it possible to follow the change of the contact position with and to reduce the defect of the gear gripping state caused by the variation of the shape accuracy and the dimensional accuracy of the gear, and prevent the deterioration of the gear processing accuracy.

[0008]

Means used in the present invention for achieving the above object is a gear holding device for holding a gear by a plurality of holding members from the outer periphery of the gear, wherein the holding member has a gear. The gear gripping device is characterized in that a chuck claw that meshes with the tooth groove is provided so as to be movable relative to the holding member in the gear circumferential direction.

[0009]

In the gear gripping device having the above structure, the gear tooth shape, tooth surface shape, tooth groove shape, gear pitch circle diameter roundness, tooth surface dimension, tooth groove dimension, gear pitch circle diameter dimension that differ from gear to gear In accordance with the above, the chuck claws provided on the sandwiching member slide on the sandwiching member in the circumferential direction of the gear to a position where the gear gripping is most stable, and the gear is sandwiched and gripped by the sandwiching member.

[0010]

EXAMPLES Next, examples of the present invention will be described below. FIG. 3 illustrates an outline of a gear center hole drilling machine provided with the gear gripping device of the present invention. Shaft heads 2 and 3 are provided on the gantry 1 so as to be slidable in the left-right direction in the drawing. The shaft heads 2 and 3 are electric motors 4 and 5 installed outside the gantry 1.
Is slidably driven on the gantry 1. Main shafts 6 and 7 are provided on the front surfaces of the shaft heads 2 and 3 so as to be rotatable around a machining center axis. The main shafts 6 and 7 are driven by electric motors 8 and 9 provided above the shaft heads 2 and 3, respectively. It is driven to rotate. Cutting tools 10 and 11 such as drills are attached to the tips of the spindles 6 and 7 to perform machining such as drilling a center hole of the gear 12.

A gear gripping device 13 according to the present invention is installed between the shaft head 2 and the shaft head 3 on the gantry 1. The gear gripping device 13 is provided with a V-shaped upper clamper 14 and a lower clamper 15 that are holding members so as to be movable in the vertical direction, and the gear 12 is sandwiched by both clampers. Although an explanation will be given here based on an embodiment in which a clamper movable in the vertical direction is used, a gear gripping device composed of a clamper movable in the direction perpendicular to the plane of the drawing may be used. Further, here, a case will be described in which two V-shaped clampers are used as the holding members to grip the gears from above and below, but a combination of the V-shaped clamper and the flat type clamper may be used as the holding members. Alternatively, a plurality of flat clampers may be used as the holding member to grip the gears from a plurality of gear radial directions.

The upper clamper 14 and the lower clamper 15 have a gear train (not shown) and a ball screw (not shown).
Are mechanically connected to each other by a fluid pressure cylinder 16 provided on the upper portion of the gear gripping device 13, and are driven in synchronization with each other in the vertical direction. Here, the vertical sliding strokes of the upper clamper 14 and the lower clamper 15 are such that the machining center axis of the main shaft and the pitch circle center axis of the gear match when gripping a gear having tooth surfaces of regular size and shape. In the state
It is set so that the gears can be machined without chattering vibrations.

Next, details of the gear gripping device of the present invention will be described with reference to FIGS. 1 and 2. As shown in FIG.
The upper clamper 14 has a V-shaped inclined portion provided with two chuck claws 17 a and 17 b which mesh with the tooth spaces of the gear, and the lower clamper 15.
On the V-shaped inclined portion, two chuck claws 17c, 17d which mesh with the tooth groove of the gear are provided so as to be movable relative to the clamper in the gear circumferential direction. If a flat clamper is used, one chuck claw is provided on the flat surface of the flat clamper so as to be movable relative to the clamper in the gear circumferential direction.

The chuck claw used in this embodiment is formed with three teeth as shown in FIG. 2 (a).
It meshes with the second tooth space. Further, the chuck claw and the clamper have an engaging portion having a T-shaped cross section. That is,
As shown in FIG. 2 (b), the chuck claw is formed with a convex portion having a T-shaped cross section, and the V-shaped inclined portion of the clamper has a concave portion having a T-shaped cross section into which the convex portion of the chuck claw fits. Since it is molded, the chuck claw does not fall from the clamper.

A chuck claw 17 is provided on the upper clamper 14.
Stoppers 18a and 18b for restricting relative movement of the a and 17b with respect to the upper clamper 14 and stoppers 18c and 18d for the lower clamper 15 are fixed to the outer circumferential end surface of the V-shaped inclined portion of the clamper in the gear circumferential direction. Further, a chuck claw 17 is provided on the inner side in the gear circumferential direction of the V-shaped inclined portion of the upper clamper.
a and 17b to the outside in the circumferential direction of the gear, that is, the stopper 18
The springs 19a and 19b, which are elastic bodies that urge in a certain direction of a and 18b, are provided.
The stopper claws 17 are provided with stoppers 20a and 20b for restricting a relative movement range of the lower clamper 15d.
c and 17d are stoppers 18c and 18d and stopper 20
It is possible to move relative to the lower clamper 15 within a predetermined range between a and 20b. The gear 12 is attached to the gear gripping device 13
As a means for carrying in, the temporary claw 21 is provided above the lower clamper 15 so as to be slidable in the direction of the pitch circle center axis 12a of the gear 12.

Next, the operation of gripping the gear 12 by the gear gripping device will be described. The gear 12 is placed on the temporary pawl 21 in a state where the tooth groove of the gear 12 and the teeth of the temporary pawl 21 are meshed with each other. The temporary pawl 21 moves in the direction of the gear pitch circle central axis 12a with the gear 12 placed thereon, and carries the gear 12 into the gear gripping device 13. Here, as the original position of the lower clamper 15, when the gear 12 is carried in by the temporary pawl 21,
Tooth of the gear 12 and chuck claws 17c of the lower clamper 15, 1
The position where the teeth of 7d are properly meshed without colliding with each other is preset. Further, the original position of the upper clamper 14 is preset such that the upper clamper 14 is separated upward so that the teeth of the chuck claws 17a and 17b of the upper clamper 14 do not hit the teeth of the gear 12 carried in by the temporary claw 21. .

Next, the fluid pressure cylinder 16 causes the upper clamper 14 to move downward, and the lower clamper 15 causes the gear groove of the gear 12 and the teeth of the chuck claws 17c and 17d to mesh with each other.
Slide 2 upward so as to separate 2 from the temporary claw 21. Since the upper clamper 14 slides downward, the tooth groove of the gear 12 and the teeth of the chuck claws 17a and 17b come into contact with each other at a certain point.

Here, like a conventional V-shaped holding member,
When gripping a gear with a chuck claw fixed to the inclined surface of a clamper that moves in the gear radial direction, that is, when gripping a gear with a chuck claw approaching while maintaining a certain angle with respect to the gear radial direction As shown in FIG. 5, the chuck jaws 22a, 22 are attached to the holding members 23a, 23b.
When b, 22c, and 22d are fixed, of the two teeth 26a and 26b forming the tooth groove 25 of the gear that meshes with the tooth 24 of the chuck claw 22a when gripping the gear, for example, it is closer to the approaching chuck claw 22a. The teeth 24a of the chuck claw 22a may collide with the side teeth 26a. this is,
This is because there is an overlap between the teeth forming the tooth groove of the gear and the teeth of the chuck claw that should mesh with the tooth groove when gripping the gear, as viewed from the clamper moving direction. Therefore, the chuck claws and the gears interfere with each other, and the clamper cannot move after the contact, or the teeth of the chuck claws or the gears are damaged.

However, in this embodiment, as shown in FIG. 1, since the chuck claw is urged outward by the spring in the circumferential direction of the gear, the teeth of the chuck claw are in contact with the teeth of the gear closer to the approaching chuck claw. The tooth flanks of the chuck claws come into contact with the tooth flanks of the gear on the far side from the approaching chuck claws without hitting. That is, even when the gear is gripped by the chuck claws provided on the inclined surface of the clamper that moves in the radial direction of the gear, the chuck claws can slide on the clamper, so that the proper gear gripping is possible. Can be realized.

As the upper clamper 14 further moves downward after the contact of both tooth surfaces, the chuck claws 17a and 17b resist the urging force of the springs 19a and 19b.
Slide on the V-shaped inclined portion 4 inward in the circumferential direction of the gear. When the upper clamper 14 reaches a predetermined stroke and ends the downward movement, the upper clamper 14 of the chuck claws 17a and 17b
The upper sliding is also completed, and as shown in FIG.
The tooth surfaces of 7a and 17b and the tooth surface of the gear 12 mesh with each other to complete the gripping.

At this time, as described above, the vertical sliding strokes of the upper clamper and the lower clamper are the pitch circles between the machining center axis of the main shaft and the gear when gripping the gear having tooth surfaces of regular size and shape. Since the central axes are set to match, if the chuck claws are fixed to the clamping member, the gears will move along the chuck claws if the teeth or tooth flanks of the gear have bad dimensions or shapes. As a result, misalignment occurs between the pitch circle center axis and the machining center axis. However, in this embodiment, since the chuck claws can move relative to the sandwiching member, the chuck claws 17a and 17b move on the upper clamper 14 even when gripping a gear with low shape accuracy and dimensional accuracy.
The chuck claws 17c and 17d can slide on the lower clamper 15 to a position where the gripping of the gear is most stable, thereby preventing the occurrence of misalignment between the pitch circle central axis and the machining central axis.

As described above, according to the gear clamp device of the present embodiment, the chuck claw that meshes with the tooth groove of the gear is provided in the clamper movably in the gear circumferential direction regardless of the V-shaped or flat clamper. It is possible to reduce defects in the gripped state of the gear due to variations in the shape accuracy and the dimensional accuracy of the gear, and prevent deterioration of the gear machining accuracy. Therefore, when the gear is used as a component, it is possible to reduce the backlash when the gear meshes.

Further, according to the gear clamp device of this embodiment, since the chuck claw is biased outward by the spring in the circumferential direction of the gear, the teeth of the chuck claw and the teeth of the gear are mutually engaged when the clamper sandwiches the gear. Do not interfere. That is, even when the gear is gripped by the chuck claws provided on the inclined surface of the clamper that moves in the radial direction of the gear, such as the V-shaped clamper, the teeth of the chuck claws when the clamper sandwiches the gear are It is possible to prevent interference with the gear teeth.

Further, according to the gear clamp device of the present embodiment, the chuck claw that meshes with the tooth groove of the gear is provided in the clamper movably in the gear circumferential direction regardless of the V-shaped or flat clamper. , Even if the chuck claw and one tooth surface of the gear come into direct contact, the chuck claw can escape.
It is possible to prevent the tooth surface of the gear from being scratched. That is, when the clamper with the fixed claws sandwiches the gear, the tooth flanks of the gear that occur when the teeth of the fixed claw and one surface of the tooth surface of the gear directly collide at the drive speed of the clamper are eliminated.

Further, according to the gear clamp device of the present embodiment, even when the clamper sandwiches a gear having low shape accuracy and dimensional accuracy, the chuck claws are geared to the clamper regardless of the V-shaped or flat type clamper. Since it is movably provided in the circumferential direction, the gear is not gripped in an unreasonable state such as gripping by a fixed claw, and scratches on the tooth surface of the gear and damage to the teeth can be prevented.

[0026]

As described in detail above, according to the gear holding device of the present invention, the chuck claws that mesh with the tooth grooves of the gear are provided on the holding member so as to be movable in the gear circumferential direction. It is possible to reduce the deterioration of the gear holding state and prevent the deterioration of the gear machining accuracy.

[Brief description of drawings]

FIG. 1 is a front view of a gear gripping device (an original position) according to an embodiment of the present invention.

FIG. 2A is a front view of a chuck claw according to an embodiment of the present invention. (B) A side view of a chuck claw according to an embodiment of the present invention.

FIG. 3 is a front view of a gear center hole drilling machine according to an embodiment of the present invention.

FIG. 4 is a front view of a gear gripping device according to an embodiment of the present invention (state of a gear gripping completion position).

FIG. 5 is a front view of a gear gripping device according to a conventional technique (when a chuck claw is fixed).

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Stand 2, 3 ... Shaft head 4, 5, 8, 9 ... Electric motor 6, 7 ... Spindle 10, 11 ... Cutting tool 12 ... Gear 12a ... Gear pitch circle center axis 13 ... Gear clamp device 14 ... Upper clamper 15 ... Lower clamper 16 ... Fluid pressure cylinder 17a, 17b, 17c, 17d ... Chuck claw 18a, 18b, 18c, 18d, 20a, 20b ... Stopper 19a, 19b ... Spring 21 ... Temporary claw 22a, 22b, 22c, 22d ... Fixed Claws 23a and 23b ... Clamper 24 ... Chuck claw teeth 25 ... Gear tooth groove 26a, 26b ... Gear tooth

Claims (1)

[Claims] 1. A gear gripping device for gripping a gear by sandwiching the gear with a plurality of gripping members from the outer circumference of the gear. In the gripping member, a chuck claw that meshes with a tooth groove of the gear is provided relative to the gripping member in the gear circumferential direction. A gear gripping device, which is movably provided.