JPS6043251B2 - Tapping unit - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a tapping unit of a machine tool, and particularly to improvements in the mechanism and control of the tool for sending off, cutting feed, quick return, etc.

Conventional tapping units operate at a constant tool feed rate.

That is, in one stroke from start to stop, the feed rate of the tool is always the same as the cutting feed rate during tapping, and many tools do not have a feed rate switching mechanism. However, looking at the current state of machining, it is common to provide a certain distance between the tool tip and the workpiece in order to insert or remove the workpiece, and due to the nature of tapping, the machining depth is limited by the thread depth. It is common for the nominal diameter to be 1.0 mm, and in normal machining, the non-cutting idle stroke is generally larger than the cutting stroke. However, in conventional equipment, the feed rate of the tool changes from the time the equipment starts until it starts cutting, and from the time it finishes cutting until it stops, that is, even when the tool is idling. is the same as the cutting feed rate, so excessive, or rather wasted, machining time was wasted. Various types of rapid feed, cutting feed, and quick return mechanisms have been proposed for drill units, but it has been difficult to apply them directly to tapping work where the feed pitch is determined. Therefore, the object of the present invention is to have a rapid feed, cutting feed, and quick return mechanism,
The clutch mechanism allows instant switching between rapid forwarding, cutting feed, and fast reversing, and the rotation is transmitted from the rotating main shaft via gears, and converted to linear motion, that is, feeding motion, by the lead screw. To provide a tapping unit that completely synchronizes rotation and feed speed and incorporates a mechanism for regulating backlash of gears, lead screws, etc.

Hereinafter, the present invention will be described with reference to illustrated embodiments. In the figure, it has one main shaft, teeth are carved on the outer periphery of the tip, a belt wheel 34 is fixed at the rear end, and a gear 2 is installed at a predetermined position in the middle.
It is made by fixing 1. Reference numeral 2 denotes a feed shaft that is slidably inserted in a predetermined position on the front end side of the main body storage box 58 within a predetermined range in the axial direction.A through hole is provided in the center of the feed shaft so that the rotary shaft 2'' can be freely rotated inside At the same time, an annular projection 57 is formed at a predetermined position on the circumferential surface, and the annular projection 57 and the annular recess 58 of the main body storage box 58
'', a spring 59 is fitted in between to always urge the feed shaft 2 in the backward direction.

The rotary shaft 2'' has teeth carved on the inner circumferential surface of a hole that opens at the rear end, and fits into the tip of the main shaft 1 so as to be slidable in the axial direction.3 is parallel to the main shaft 1. There is a clutch shaft installed in the front end of the joint 4 with a built-in torque limiting mechanism.
A gear 26 is connected to the lead screw 4 via a gear 6, and the rear end rotatably supports a gear 26 having clutch meshing teeth 34 on the front side, and a protrusion 35 on the rear side at a predetermined position in the middle part. rotatably supports a belt pulley 33 having
A protrusion 36 is provided between the gear 26 and the belt wheel 33, which rotates together with the clutch shaft 3 and is movable in the axial direction, and which is engageable with the projection 35 of the belt wheel 33 on the front side surface. A clutch 40 having teeth 37 that can freely engage with the teeth 34 of the gear 26 is supported on the rear side.

Reference numeral 5 denotes an intermediate shaft parallel to the main shaft 1. A gear 22 is fixed to the front end of the intermediate shaft so as to engage with the gear 21, and a gear 23 is removably fitted to the rear end of the intermediate shaft.

The floating shaft 9, which has a gear 25 that engages with the gear 26 and a removable gear 24 that engages with the gear 23, is attached to the support plate 5.
3, the clutch shaft 3 is rotatable and rotatable at a certain angle about the axis of the clutch shaft 3, and is supported parallel to the main shaft 1.
The hole 51 is formed concentrically with the axis of the clutch shaft 3 in order to fit the stepped portion 54 provided on the support plate 53, and the hole 52 is formed concentrically with the axis of the clutch shaft 3.
A bearing portion 55 provided on the support plate 53 is loosely fitted to rotatably support the floating shaft 9. Reference numeral 56 denotes a set screw for fixing the support plate 53 to the main body storage box 58.

Reference numeral 6 denotes an intermediate shaft with a built-in torque limiting mechanism, and the front end has a gear 27 that engages with teeth 29 carved on the outer periphery of the output shaft 7 of the electric motor 10, which is capable of forward and reverse rotation, and the rear end has the aforementioned gear 27. Main shaft 1
It consists of a belt pulley 34 fixed to the rear end and a belt pulley 30 connected by a belt 41, and is configured parallel to the main shaft 1.

Reference numeral 8 denotes an intermediate shaft, to which a gear 28 that engages with the gear 27 is fixed to the front end, and which is connected to a belt wheel 33 supported by the clutch shaft 3 by a belt 42 to the rear end. It consists of a fixed belt pulley 32 and is configured parallel to the main shaft 1.

Reference numeral 59 denotes an arm for engagement with the lead screw 4 that is fitted and fixed at a predetermined position on the peripheral surface of the rear end side of the feed shaft 2, and the tip end thereof is fixed to the nut 38 screwed onto the lead screw 4, and other The end side has an extension portion provided with the dogs 47, 48, 49 whose positions are freely adjustable at predetermined positions.

Reference numerals 103, 104, and 105 indicate limit switches for checking the fast feed end, cutting end, and backward end, which are provided at predetermined positions inside the main body storage box 58 so as to be able to collide with the dog, respectively.
The electric motor 101 includes a limit switch 1 for checking the cutting edge.
It is configured to rotate in the opposite direction in response to a signal from 04.

Reference numeral 102 denotes a clutch switching solenoid, which is always biased toward the rear end by a spring 110 whose one end is fixed to the main body storage box 58, and which is connected to a solenoid arm 43, a clutch rod 44, and a clutch arm 45. The clutch 40 is always connected to the belt wheel 3 via a link mechanism consisting of
3, and is excited by a signal from the fast-forward end confirmation limit switch 103 to move the clutch 40 back and forth to enable switching.

Next, the functions and effects of the present invention will be explained.

The electric motor 101 is energized by the start signal and the motor shaft 7 rotates, and the gear 27 fixed to the front end of the intermediate shaft 6 engages with the teeth 29 carved at the front end of the motor shaft 7, and the rear end. The main shaft 1 is rotated through a belt pulley 30 fixed to the rear end of the main shaft 1, a belt pulley 34 fixed to the rear end of the main shaft 1, and a belt 41 wrapped around the belt pulley 30. Rotate the rotary shaft 2'' on which the parts are fitted.

At the same time, a belt wheel 33 is rotatably supported on the clutch shaft 3 via a gear 28 fixed to the intermediate shaft 8 to engage with the gear 27, a belt 32, and a belt 42 wrapped around the belt wheel 32. Rotate. On the other hand, the clutch shaft 3 is fitted with a latch 40 that rotates integrally with the clutch shaft 3 and is slidable in the axial direction.
4. Since the clutch 40 is always pressed against the belt pulley 33 via the clutch arm 45, a protrusion 35 and the clutch 4 are provided on the rear end surface of the belt pulley 33.
The protrusion 36 provided on the front side of the belt pulley 53 is engaged, and the rotation of the belt pulley 53 is transmitted to the clutch shaft 3 via the clutch 40. Then, the clutch shaft 3 and the lead screw 4 connected through the joint 46 are rotated, and the nut 38 screwed onto the lead screw 4 is advanced, and the arm 39 is rotated.
By moving forward, the feed shaft 2 is moved forward.
At this time, the rotating shaft 2'' rotates integrally with the main shaft 1, and
Although it moves forward integrally with the feed shaft 2, since the rotating shaft 2'' and the main shaft 1 are configured to be slidable in the axial direction, the rotating shaft 2'' can move forward while rotating. Here, when setting the rotation ratio of the teeth 29, gears 27 and 28, and belt wheels 32 and 33, the feed speed of the feed shaft 2 is set to be higher than the feed speed during cutting feed, as in the embodiment. As a result, when the tool is idling, rapid traverse is performed, and the tool can quickly reach the cutting position. Feed shaft 2
As the arm 39 moves forward, the dogs 47, 48, 49 attached to the extension of the arm 39 also move forward, and the dog 42 first comes into contact with the limit switch 103. At this time, the solenoid 102 is switched by a signal issued by the limit switch 103, and the protrusion 35 provided on the belt 33 moves the clutch 40 rearward via the solenoid arm 43 and the clutch arm 45. The engagement of the protrusion 36 provided on the clutch 40 is disengaged, the rotation of the clutch shaft 3 and the lead screw 4 is stopped, and the forward movement of the feed shaft 2 is stopped. At the next moment, the clutch 40 connects the tooth 37 and the gear 2.
By engaging the teeth 34 provided at 6, the cutting feed rate is switched to a lower speed than before. That is, a gear 22 fixed to the intermediate shaft 5 to engage with the gear 21 fixed to the main shaft 1, a gear 23 fitted to the intermediate shaft, and a gear fitted to the floating shaft 9 to engage with the gear. After 24 years,
The clutch shaft 3 rotates via the gear 25, gear 26, and clutch 46, and the nut 38,
The feed shaft 2 is advanced via the arm 39. Here, when setting the number of teeth of the gears 21, 22, 23, 24, 25, 26, the pitch of the lead screw 4 is taken into consideration, and The feed rate is set to match the pitch of the screw to be cut.The clutch 40, which is switched by the solenoid 102, rotates at the cutting feed rate, and the clutch shaft 3, the joint 46, and the male lead screw arm 39 are rotated at the cutting feed rate. The feed shaft 2 is advanced through
Move forward until you hit 4. During this time, the abutting relationship between the dog 47 and the limit switch 103 is maintained. dog 48
The signal generated by limit switch 104 due to the collision causes motor 101 to rotate in the opposite direction. At this time, the abutting relationship between the dog 47 and the limit switch 103 is still maintained, and the clutch 4
0 remains engaged with the cutting feed side, that is, the gear 26, so as the electric motor 101 rotates in the opposite direction, the main shaft 1 and the rotary shaft 2'' rotate in the opposite direction, and at the same time the feed shaft 2 will move backward at the cutting feed pitch. When the dog 47 continues to move backward and the collision relationship with the limit switch 103 is released, the solenoid lens 102 is switched by the signal issued from the limit switch 103, and the clutch 40 is turned on. Since the clutch shaft 3 is switched to engage with the opposite side, that is, the belt pulley 33, the clutch shaft 3 switches from the previous low-speed cutting feed rotation to a high-speed fast return rotation. The rotation is performed by retracting the feed shaft 2 at a quick return speed via the gate joint 46, lead screw 4, nut 38, and arm 39 until the dog 49 provided on the extension of the arm 39 engages the limit switch 105. Then, the electric motor 101 is stopped by a signal generated by the collision between the dog 49 and the limit switch 105, and one cycle of machining is completed.
, 48, and 49, the fast forward, fast return stalk, cutting feed start position, and forward end/reverse start position can be freely set within a certain range. Furthermore, there are various pitches depending on the diameter of the screw, and the feed speed of the feed shaft 2 must be adapted to each pitch. Therefore, in the cutting feed rate transmission mechanism, the gear 23,
24 is removable, and is configured to adapt to various pitches by combining gears. However, depending on the combination of gears, the distance between the intermediate shaft 5 and the floating shaft 9 may differ. Therefore, in order to absorb changes in the distance between the shafts, the floating shaft 9 is configured to be movable. That is, a hole 51 concentric with the clutch shaft 3 is provided in the outer surface of a bearing plate 50 that forms a part of the main body storage box 58 and supports the clutch shaft 3, and the floating shaft 9 is supported by the bearing part 55 of the support plate 53. A step 5 is provided in the support plate 53, and a hole 52 is provided in order to pass through the support plate 53.
4 into the hole 51, the support plate 53 is configured to be able to rotate around the hole 51, that is, the axis of the clutch shaft 3. If it becomes necessary to change the distance between the intermediate shaft 5 and the floating shaft 9 by replacing the gears 23 and 24, first loosen the set screw 56 and rotate the support plate 53 about the clutch shaft 3. Next, the gears 23 and 24 are converted into gears with a number of teeth that match the screw pitch, and each intermediate shaft 5,
It is fixed to the floating shaft 9, the support plate 53 is rotated around the clutch shaft 3, the gears 23 and 24 are engaged, and the set screw 5 is fixed.
At step 6, the support plate 53 is fixed to the bearing plate 50. Here, the floating shaft 9 supported by the support plate 53 rotates together with the support plate 53, but since the rotation center of the support plate 53 coincides with the axis of the clutch shaft 3, the floating shaft 9 is rotated along with the clutch shaft 3. On the other hand, the gears 25, 2, and 6 rotate while always maintaining a constant distance, and the distance between the intermediate shaft 5 and the floating shaft 9 can be changed while always maintaining the engagement relationship. The present invention has the above-mentioned rapid forwarding, cutting feeding, and quick reversing mechanisms, and also uses a clutch mechanism to instantly switch between rapid forwarding, cutting feeding, and fast reversing! can.

Furthermore, since rotation is transmitted from the rotating main shaft via gears and converted into linear motion, that is, feeding motion, by the lead screw, the main shaft rotation and the feed speed can be perfectly synchronized. Furthermore, since the feed shaft is configured to always be biased rearward by a spring, play in the power transmission path and play in the tool due to backlash can be minimized. For this reason, in the past, especially in small-diameter screws, the threads were destroyed by the play of the tool when the tool was removed, making it difficult to precisely machine the screws, but the present invention overcomes the above-mentioned conventional drawbacks. In addition to making it possible to precisely process small-diameter screws by releasing the device, all types of screws can be processed in a short time.In terms of processing time, compared to conventional equipment, the processing time is 112 to 113 times. This could have been shortened, and the effect is significant.
In addition, since the distance between the clutch shaft and the idler shaft can be changed, the gears 17 and 28 can be selected from ordinary gears with any number of teeth. Conventionally, when selecting gears, the distance between the shafts is fixed. Therefore, it is often necessary to use a transition gear, and it is possible to solve the disadvantages that some screw pitches cannot be machined depending on the thread pitch, so the industrial merit is extremely large.

[Brief explanation of the drawing]

FIG. 1 is a vertical cross-sectional side view showing an embodiment of the present invention, FIG. 2 is an enlarged vertical cross-sectional view showing a mechanism for adjusting the distance between the intermediate shaft 5 and the floating shaft 9, and FIG. FIG. 1: Main shaft, 2: Feed shaft, 2'': Rotating shaft, 3: Clutch shaft, 4: Lead screw, 5, 6, 8: Intermediate shaft, 7: Motor output shaft, 9: Idler shaft, 21, 22, 23, 24, 2
5, 26, 27, 28: Gear, 30, 31, 32, 33
: Belt wheel, 34, 37: Teeth, 35, 36: Protrusion, 38
: Natsuto, 39: Arm, 47, 48, 49: Dog, 53:
Support plate, 58: Main body storage box, 101: Electric motor, 102:
Solenoid, 103, 104, 105: Limit switch.

Claims (1)

[Claims] 1 The main body storage box is penetratingly supported at a predetermined position on the front end side so that it can move forward and backward and always biased in the backward direction, has a through hole that communicates with the inside in the axial direction, and is further provided with a lead screw at a predetermined position on the peripheral surface on the rear end side. a feed shaft equipped with an arm for engagement with the through hole; a main shaft rotatably fitted into the through hole on the front end side and equipped with a driving force transmitting member at a predetermined position on the peripheral surface of the rear end side; a rotary shaft that is fitted into the hole and is engaged with the main shaft so that it can freely slide in the axial direction and rotate with the main shaft; A lead screw that together moves the feed shaft in the front and back direction together with the rotary shaft; a clutch shaft that is commonly connected to the rear end of the lead screw; A pair of front and rear driving force transmitting members that are supported reversibly at a distance, and a pair of driving force transmitting members that are disposed in an intermediate portion of each of the driving force transmitting members to be slidable in the axial direction and rotatable with the clutch shaft. a clutch mechanism including a clutch for switching a transmission member; a transmission mechanism that transmits the rotational force of the electric conduction machine to the driving force transmission member of the main shaft; and a transmission mechanism that transmits the rotational force of the electric conduction machine to the front end side driving force transmission member of the clutch mechanism. a transmission mechanism configured to transmit the rotational force of the main shaft at a predetermined rotational ratio to the rear-end driving force transmission member of the clutch mechanism and to be able to change and set the rotational ratio; a dog disposed at the other end or at a predetermined position on the rear end side of the feed shaft so as to be adjustable in position; a limit switch disposed in the main body storage box so as to be able to abut against the dog; A tapping unit comprising a clutch actuation mechanism that switches and operates the clutch freely in response to a signal from a switch.