JPH01176624A - Bending device of ring-form glass pipe - Google Patents

Abstract

PURPOSE:To carry out a ring-form bending process smoothly by making it possible to control the straight movement and the rotation of a formation device separately. CONSTITUTION:By the rotation of a motor 30 to lift formation drums, an elevator stand 5 is moved up and down. This motor 30 is a variable speed motor, and the speed is changed responding to the signal fed from a control circuit 34. And a motor 31 to rotate the formation drums is also a variable speed motor, changing the speed responding to the signal fed from the control circuit 34, and can convert the rotation speed of the formation drums 25a and 25b. The rising speed and the rotation speed of the formation drums 25a and 25b can be selected as desired consequently. The straight movement speed or the rotation speed can be controlled to make the glass pipe in an even thickness accordingly even though an uneven softening resulting from the heating condition of the glass pipe or an uneven extension condition when the glass pipe is wound is generated.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Field of Application) The present invention relates to an apparatus for bending a heat-softened straight glass tube into an annular shape around the circumferential surface of a forming drum.

(Prior art) The glass tube for the 2-ring after-reflection fluorescent light is made by heating and softening a straight glass tube in advance, and then winding the glass tube around a forming groove formed on the circumferential surface of a forming drum and bending it into an annular shape. This method is already known.

A conventional molding apparatus of this type will be explained with reference to FIGS. 7 and 8.

In FIG. 7, a deck 4 is fixed via a table 1, a frame 2, and a guide support 3. In FIG.

An elevating table 5 is attached to the guide column 3 so as to be slidable up and down, and the elevating table 5 is suspended by a five-piece chain 6.

This chain 6 is passed to the top of the deck 4, which is fixed to the upper surface of the deck 4.
It is wound around a take-up foil 8 attached to. In addition, 9
is a balance weight.

A cylinder 10 is attached to the table 1, and a rack 11 is fixed to the piston rod of the cylinder 10. A binion 12 is engaged with the rack 11, and the binion 12 rotates together with the take-up wheel 8.

Therefore, when the cylinder 10 is extended, the pinion 12 meshing with the sleeve 11 rotates the take-up wheel 8, so that the take-up wheel 8 rotates the chain 6 into the take-up wheel. , the lifting platform 5 is raised.

As shown in FIG. 8, the lifting platform 5 is provided with a drive shaft 15 in the horizontal direction, and a pinion groove is attached to one end of the drive shaft 15. And above table 1
A rack 17 is installed vertically between the deck 4 and the deck 4, and the pinion 16 is engaged with the rack 17. Therefore, when the lifting platform 5 moves up and down, the pinion 16 rotates due to the meshing action of the rack 17 and the pinion 16.
Therefore, the drive shaft 15 is also rotated.

The drive shaft z5 has multiple sets of drive gears 201° 20b.
are fixed, these drive gears 20&.

Driven gears 22m and 22b mesh with 20b via intermediate gears 21m and 21b, respectively.

The driven gears 22*, 22b include a forming drum 25*,
25b is fixed. These forming drums 25*, 2
5b are K when they are brought close to each other.

A molding groove 26 is formed around the periphery. Also.

The forming drums 25h, 25bK are attached to the chuck arm 27a.
, 27b is fixed, and the chuck arm 27
g and 27b clamp one end of the glass tube G when they are brought close to each other.

The forming drums 25s1 and 25b are moved toward and away from each other by a cylinder or the like (not shown).

In such a configuration, when the straight glass tube G, which has been softened by being heated in the heating furnace, is transported to the above-mentioned bending device by the transport head (not shown), the straight glass tube G is One end of the forming drums 25h, 2! of the lifting platform 5 in the lowered position are spaced apart from each other. ib chuck arm 27&.

27b.

The forming drum 2 is moved by a drive device such as a cylinder (not shown).
5*, 25b are approached in the axial direction, and thereby the chuck arms 27g, 21b clamp one end of the straight glass tube G in the softened state.

In this state, when the cylinder 10 is extended, the binion 12 meshing with the rack 11 rotates the take-up wheel 8, and the take-up wheel 8 takes up the chain 6 and lifts the elevator platform 5. raise.

When the lifting platform 5 moves upward, the pinion 16 rotates due to the meshing action of the two pinions 17 and the pinion 1g, and therefore the drive shaft 15 also rotates.

The rotation of the drive shaft 15 rotates the drive gears 20m and 20b, so the driven gears 22* and 2;lb are rotated via the intermediate gears 21* and 21b, respectively, and thus the forming drum 2
5*, rotate 21b.

Therefore, the softened glass tube is wound around the forming groove 26 formed around the forming drums 25 &, :lb, and as a result, the glass vG has a radius corresponding to the radius of the forming groove 1. It will be bent into a ring shape.

When such bending is completed, the glass tube G is cooled and solidified. After the glass tube G is sufficiently cooled and solidified, the forming drums 21m and 2 are moved by a driving device such as a cylinder (not shown).
1b to separate them from each other, and the annular glass tube G
In the apparatus for bending annular glass tubes as described above, the lifting platform 5 is raised by a single pneumatic or hydraulic cylinder 10, that is, the forming drum 25a.

Since it drives the rise of Z5b and the rotation of the forming drums 25* and 25b, it has the advantage of requiring only one drive device.
On the other hand, the relationship between the rising speed and rotational speed of the forming drums 25m and 25b is fixed.

In addition, if the drive device is a cylinder, it is difficult to control the expansion and contraction speed, and even if the expansion and contraction speed can be controlled, the lifting platform 5, that is, the forming drums 25*, 2
As the rising speed of 5b becomes slower, the rotational speed inevitably becomes slower.

However, when the glass tube is heated, it tends to soften unevenly, and the degree of elongation when it is wound around the forming drum 251° 25b is also uneven.

Therefore, it is desirable to independently control the elevation and rotation.

In particular, when trying to bend glass tubes of different sizes using the same equipment, the glass diameter and annular radius are different, so it is necessary to change the forming drum to one with a different diameter. In some cases, the circumferential speed becomes too high relative to the rising speed, resulting in problems such as annular bending being unable to be carried out smoothly.

The present invention aims to provide an annular glass tube bending device in which the linear movement and rotation of a forming r-ram can be controlled separately.

The present invention provides a variable speed first motor that linearly moves a forming drum in one direction and a variable speed second motor that rotates the forming drum separately from each other. It is characterized in that the motor and the second motor are rotated in synchronization with each other.

(Function) According to the present invention, the linear movement speed of the forming drum in one direction and the rotational speed of the forming drum can be controlled to be synchronized with each other. Therefore, even if the degree of softening occurs due to the degree of heating of the glass tube, or the degree of elongation during winding is not uniform, good bending is possible by controlling the linear movement speed or rotational speed. Furthermore, even when changing the forming drum in order to bend glass tubes of different sizes using the same device, the circumferential speed can be controlled and good bending is possible.

(Example) The present invention will be described below based on an example shown in FIGS. 1 to 3.

In this embodiment, the same members as those shown in FIGS. 7 and 8 are designated by the same reference numerals, and the description thereof will be omitted.

A lifting platform 5 attached to the f-id support 3 so as to be able to rise and fall is suspended by a chain C, and this chain 6 is driven by a forming drum lifting motor, ffO, which is attached to the upper surface of the deck 4. Sprocket to be used) 7 a
After the K hook has been passed, it is connected to another sprocket (toybt-single balance way) 9.

Therefore, the lifting platform 5 is moved up and down by the rotation of the forming drum lifting lever 30. The molding drum lifting motor 30 is a variable speed motor such as a motor or a stepping motor, and its speed changes according to the signal supplied from the control circuit 34, so that the lifting speed of the lifting platform 5 can be changed. Can be done.

A molding drum rotation motor 3 is attached to the lifting table 5. This molding drum rotation starter 311fi is connected to the drive shaft 15 via bevel gears 32 and 33.

This molding drum rotation motor 31 is also a variable speed motor such as a sage motor, a step motor, a pin motor, etc., and its speed changes according to the signal supplied from the control circuit 34, thereby controlling the rotation of the molding drums 25 m and 21b. You can change the speed.

According to such a configuration, the forming drum lifting motor 30 and the forming drum rotation motor 31 have different roles, and their respective rotational speeds can be controlled, so that the rising speed of the forming drums 25*, 25b and rotation speed can be selected arbitrarily.

Therefore, for example, when using a forming drum with a large diameter, the amount of glass tube that is rolled in is large due to the large diameter of the drum, so the optimum bending can be set by slowing down the rotation speed without changing the rising speed of the forming drum. be able to.

FIG. 3 is a block diagram showing details of the control circuit 34. This control circuit 34 includes a command pulse generation circuit 36 which generates a command pulse to cause the forming drum lifting motor 30 to perform a predetermined operation, a D/A converter 40 with a deviation of 38%, and a sensor. Driver 42. Rotation angle detector 44 of the motor 30 for lifting the forming drum. Ratio setting device 4
6. Ratio setting switch 48. Molding drum rotation motor 3
Deviation counter 50 for no. D/A converter 52
, the driver 54 and the forming drum rotation upper rotor 31
and a rotation angle detector 56. Motors 30, 21 in this embodiment are AC or DC motors.

The command pulse from the command pulse generation circuit 36 is inputted to the terminal (■) of the deviation counter 38, and the number of nonals is counted. A voltage proportional to the amount of pulses accumulated in the deviation counter 38 is output from the D/A converter 40, and a The signal is amplified by the driver 42. The molding drum lifting motor 30 rotates in response to this amplified voltage, and the angle of rotation is detected by the angle detector 44. This detection result is fed as a pulse to the e terminal of the deviation counter 38, and the number of stored pulses in the deviation counter 38 is subtracted.

Further, the above detection result is input to the ratio setting device 45. At this time, the frequency of /1 pulse from the angle detector 44 is divided by the ratio set by the setting switch 48, and the pulse obtained as a result of this frequency division is applied to the ■ terminal of the deviation counter 50 of the rotation motor 31. is input. Output V of deviation counter 5o
input to the iD/A converter 52 and the deviation counter 50
A voltage proportional to the amount of pulses accumulated in Vc is output from the D/A converter 52. This output voltage is amplified by a driver 54, and the forming drum rotation motor 31 is rotated in accordance with this amplified voltage. Motor 3 for rotation with
The rotation angle of 1 is detected by the angle detector 56, and the detection result is fed to the e terminal of the deviation counter 50 as /4A-s.

By means of the control circuit 34 configured in this manner, the rotation angles of the forming drum lifting motor 3σ and the forming drum rotating motor 31 are synchronized at a predetermined ratio.

According to this embodiment, the linear movement speed of the forming drum in one direction and the rotational speed of the forming drum can be controlled to be synchronized at a predetermined ratio. Therefore, even if there is variation in softening depending on the heating condition of the glass tube, or even if the degree of elongation during wrapping is not uniform, the thickness of the glass tube can be made uniform by controlling the linear movement speed or rotational speed. Good bending is possible. Furthermore, when changing the forming drum to bend glass tubes of different sizes using the same device, the peripheral speed of K can be controlled, so that good bending is possible.

Furthermore, since the synchronization ratio can be easily changed, the relationship between linear movement amount and rotation angle can be adjusted. Therefore.

Even if there are variations in the softening of the heated glass tube, good bending is possible by adjusting the synchronous ratio.

Another embodiment of the control circuit 34 used in the present invention will be described with reference to FIG. In this embodiment, the ratio setting device 46
The ratio setting is set based on the glass temperature information of the glass tube. That is, the output signal from the glass temperature detector 60 is input to a control device 58, which may consist of, for example, a sequencer or a microphone processor, and the control device 58 forms a ratio signal. Based on this ratio signal, the pulse generated from the angle detector 44 is frequency-divided, and the forming drum rotation motor 31 is driven. The rest of the structure is the same as that shown in FIG. 3, so the same parts are given the same reference numerals and detailed explanation thereof will be omitted.

In this embodiment, a signal for setting the optimum synchronization ratio for the glass temperature is supplied from the control device 58 to the ratio setting device 46. is heated to approximately 700° C. to 770° C., and immediately after being wound into a ring around a forming drum, air is blown thereto to cool it down. If the temperature of the glass tube is constant, there is no problem, but if the temperature rises, even if you blow air on it, it will not be sufficiently cooled and the angle of entrapment will become wider when the forming drum is removed. If the control circuit 34 of this embodiment is used, the synchronization ratio can be adjusted,
If you wrap it up a lot in advance, you won't have to make a defective runde even if the temperature changes.

Since the glass tube can be wound around the forming drum at an optimal synchronous ratio with respect to the temperature of the heated glass tube, a stable bending device can be realized.

Next, referring to FIG. 5, the control circuit 34 used in the present invention
0 Yet another embodiment will be described. Control circuit 3 of this embodiment
Reference numeral 4 includes a command pulse generation circuit 36, a pulse motor driver 70, a ratio setting switch 48, a ratio setting device 46, and a pulse motor driver 12. In this embodiment, the motor 30 for lifting the forming drum and the motor 31 for rotating the forming drum are composed of step motors.

The pulse train from the tl pulse generation circuit 36 is sent to a /4' smoke driver 70, and its output rotationally drives the forming drum lifting motor 30. Further, the Nors sequence is input to a ratio setting device 46, and a setting switch 48
The pulses frequency-divided by the ratio set in are supplied to the /4 pulse motor driver 72. The output of the pulse motor driver 72 rotationally drives the motor for rotating the forming drum.

In this way, the two motors 30 and 31 in this embodiment also rotate in synchronization at a predetermined ratio.

Next, referring to FIG. 6, the control circuit 34 used in the present invention
Yet another embodiment will be described. Control circuit 3 of this embodiment
4, the ratio setting is made dependent on the glass temperature. The operations of the glass temperature detector 60 and the control device 58 are the same as in the embodiment shown in FIG. 4, and the other configurations are the same as in the embodiment shown in FIG. Therefore, detailed explanation thereof will be omitted.

The effect of this embodiment is the sum of the effects of the embodiments of FIGS. 4 and 5, respectively.

As another example, there is also the following example that does not use a temperature sensor.An annular glass tube bending device such as this device is usually a rotary device with a large number of heads. Ki
A straight glass tube is attached to the book, and it comes out shaped into a ring. In this case, if a straight glass tube is not installed in a certain head, no heat is removed from the heating furnace, so the temperature of the next glass tube will be higher than the normal temperature. By adjusting the synchronization ratio as described above and winding the glass tube more than usual, a stable bending device can be obtained.

Note that the present invention is not limited to the above embodiments.

That is, in the above embodiment, a case has been described in which the forming drum is moved in the vertical direction, but the forming drum may be moved in the horizontal direction to bend the glass tube.

Further, in the above embodiment, the forming drum rotation motor 31 is synchronized with the operation of the forming drum hoisting motor 30, but the reverse may of course be used.

〔Effect of the invention〕

As explained above, according to the present invention, the linear movement speed of the forming drum in one direction and the rotational speed of the forming drum can be controlled to be synchronized, so that variations in softening occur depending on the heating condition of the glass tube. Even if the degree of elongation during wrapping is not uniform, by controlling the linear movement speed or rotational speed, the thickness of the glass tube can be made uniform and good bending is possible.

Furthermore, even if the forming drum is changed in order to bend glass tubes of different sizes using the same device, the circumferential speed can be controlled and good bending becomes possible.

Furthermore, since the synchronization ratio can be easily changed, the relationship between the amount of linear movement and the rotation angle can be adjusted. Therefore, even if there are variations in the softening of the heated glass tube, good bending is possible by adjusting the synchronization.

[Brief explanation of the drawing]

1 to 3 show one embodiment of the present invention, in which FIG. 1 is an overall perspective view, FIG. 2 is a sectional view taken along the par T1 line in FIG. 1, and FIGS. 3 to 6 The figure is a block diagram of the control circuit used in the present invention, Figures 7 and 8 show the conventional structure, Figure 7 is an overall perspective view, and Figure 8 is the line FIG. DESCRIPTION OF SYMBOLS 1...Table, 2...Frame, 3...Guide support, 4...Deck, 5...Elevating platform, 6...Chain, 15-...Drive shaft, 20m, 110b-Drive Gear, 21h. Z l b - Intermediate gear, 22 m, 22 b
... Driven gear, 25*, 25b ... Forming drum, 2
6-... Molding groove, 27*, 27b... Cha, firm, 30... Molding drum lifting motor, 3...
Molding drum rotation motor, 34... control circuit, 36-
...Command pulse generation circuit, 38, 50--Deviation counter, 40, 52□-D/A converter, 4j, 54
-...Sir is a driver, 44j56-...Angle detector,
46--ratio setting device, 48--setting switch, 5
8... Control device, 60... Glass temperature detector, 70
．． 72--Pulse motor drive. Applicant's agent Patent attorney Takehiko Suzue Figure 1 Figure 7

Claims (5)

[Claims] (1) A forming drum that locks one end of a heated and softened straight glass tube, a variable speed first motor that linearly moves the forming drum in one direction, and a variable speed motor that rotates the forming drum. a second motor for deformation, and a control means for controlling the first and second motors so as to be synchronized with each other, and the glass tube is wound around the peripheral surface of the drum and bent into an annular shape. A device for bending annular glass tubes. (2) The control means includes angle detection means for detecting the rotation angle of one of the first or second motors;
and rotation means for rotating the other motor of the first or second motor in synchronization with the one motor so as to follow at least the rotation angle detected by the angle detection means. An apparatus for bending annular glass tubes according to claim (1). (3) According to claim (2), the rotating means changes the synchronization ratio of the first and second motors based on a signal indicating the tube wall temperature of the straight glass tube. Annular glass tube bending equipment. (4) The first and second motors are AC motors or DC motors.
Claim No. (1) characterized in that it is a motor.
An apparatus for bending an annular glass tube according to any one of items 1 to 3. (5) The first and second motors are step motors, and the control means controls the first and second motors by applying two pulse trains each having a required frequency to the respective step motors. An annular glass tube bending device according to claim 1, characterized in that the bending device is synchronized.