JPS6243931B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention consists of a loading station, a furnace, a cooling unit and an unloading station, each comprising a horizontal conveyor formed by a horizontal roller platform for supporting and transporting glass sheets on a horizontal surface. the furnace defines a passage extending in the conveying direction, both ends of the passage have horizontal slits for passing the glass plate, and the furnace heats the glass plate to the softening temperature of the glass plate; and an element operably connected to each of said conveyors to operate the conveyors at predetermined intervals to transport glass sheets from said loading station to a furnace, from the furnace to a cooling unit, and from the cooling unit to an unloading station. The present invention further relates to a glass plate tempering apparatus including a furnace conveyor, a cooling unit conveyor, and drive means for swinging and driving the glass plate during the conveying cycle.

A device of this type is disclosed in British Patent No. 1527782 of the same applicant. This device is suitable for use with small glass plates of different sizes and thickness, since the time that the glass plates remain in the furnace can be selected as desired by selecting a fixed rocking cycle duration, which has been empirically predetermined for each type of glass. It is characterized by being suitable for processing large quantities of glass plates. In this respect, continuous operation furnaces are suitable for processing large quantities of glass sheets, as their minimum length is determined by the heating time and the minimum transfer rate, and the conditions for new types of glass sheets (such as feed rate and temperature) It takes a long time to change. In a tempering furnace at about 700°C, it is necessary to hold the glass plate (5 mm thick) for 200 seconds to reach a softening temperature of about 360°C, which results in a minimum transport speed of about 10-15 cm/sec. It is therefore clear that a continuous operating furnace would require a considerable length.

For these reasons, it has been found that driving the conveyor of the furnace and cooling unit in an oscillating or reciprocating manner during the heating and cooling cycles of the glass sheet provides good results in the tempering apparatus. This equipment can be easily adjusted to meet the requirements of new and different types of glass and is therefore used for tempering a wide variety of small quantities of glass sheets. Additionally, shorter furnace and cooling units save space and cost. The purpose of the rocking motion is to eliminate deflection of the glass plate between the rollers of the roller bed. This deflection phenomenon becomes particularly dangerous during the final rocking movement in the furnace when the glass sheet is in its softened state. The above-mentioned British Patent No. 1,527,782 discloses appropriate rocking, acceleration and transport distance data to eliminate deflection between the rollers and noticeable bending of the glass pane. One of the problems here lies in the transfer of the glass sheets from the furnace to the cooling unit; the speeds of the furnace and cooling unit must be precisely synchronized with each other during this transfer cycle. This problem is solved by making the lengths of the furnace and cooling unit equal and by always driving the furnace and cooling unit synchronously at the same speed. However, this solution is not economically acceptable since the cooling unit with the conveyor and several tubes for blowing the cooling air becomes very expensive and must be kept as short as possible in view of the requirements of the cooling technology. In the cooling unit, it is only necessary to move the glass plate in such a way that the cooling air is evenly distributed over the surface of the glass plate. Therefore,
The cooling unit is considerably shorter than the furnace, and the swinging distance required for the cooling unit is also reduced.
The problem here is to make the cooling unit rocking stroke length shorter than the furnace rocking stroke length during the rocking cycle, while changing the conveyor speed during the transfer cycle from one station to the other. The goal is to drive the furnace conveyor and cooling conveyor in precise synchronization with each other. Although GB 1,527,782 does not disclose any structural solution to this problem, it does indicate that the drive systems of the cooling unit and the furnace conveyor may be separated from each other or synchronized with each other.

In the glass plate tempering apparatus disclosed in U.S. Pat. No. 3,994,711, this problem is solved by two independently operated drive motors that drive the conveyors of the furnace and cooling unit. However, only the problem with rocking has been solved; the problem of having a long conveying stroke to transfer the glass sheets from the conveyor of the furnace to the conveyor of the cooling unit remains. Since there is no integral or mechanical connection between the furnace conveyor and the cooling unit conveyor, the speeds of both conveyors must be synchronized by electrically controlling separate drive motors.

The object of the invention is to solve the problem in a new way, in which the movements of the conveyors of the furnace and cooling unit are ideally controlled relative to each other during rocking cycles and long conveying strokes.

According to the invention, the above object is to provide a common drive motor connected to one of the furnace conveyor and the cooling unit conveyor by a variable speed gear and to the other by a fixed transmission. This is achieved by providing a conveyor.

The calculation of the predetermined optimal position of the transmission gear is performed by a microprocessor, which is used to optimize the overall operation of the device as described below.

Preferred embodiments of the invention will now be described with reference to the accompanying drawings.

The glass plate tempering apparatus comprises rollers 10, 20, 3 which support and transport the glass plates through the apparatus.
It includes in sequence a loading station 1, a furnace 2, a cooling unit 3 and an unloading station 4, each provided with a horizontal roller platform formed by a roller holder 0,40. The conveyor formed by each roller bed is shown in FIG.
is shown. Each roller is connected to a common drive means by a band or chain connecting the drive wheel at the end of the roller. The construction, support, and drive means for rollers are well known and will not be discussed herein; reference is made to U.S. Pat. sea bream.

The furnace 2 forms a through passage 21, the end of which towards the loading station is provided with an inlet opening 23 formed as a horizontal slit, and the opposite end is provided with an outlet opening 24. . Furnace 2 is approximately 700℃
It includes a heating resistor 22 that maintains the temperature at .

The cooling unit 3 comprises a number of tubes spaced apart from each other by a short distance, and cooling air blowing means 31 for blowing cooling air through the tubes onto both surfaces of one or more glass sheets located on the roller 30. on each side of the roller bed.

The conveyor drive shown in FIG.
A common motor 5 is provided for driving a drive wheel 26 of a roller platform (formed by a roller platform). Through a strip, chain, etc., the drive motor 5 drives the conveyor 12 of the cooling unit in two configurations. In turn, the band or chain 6 drives, via an electromagnetic clutch, a band or chain 34 which drives a drive wheel 35 of the conveyor 47. The transmission ratio of the drive system via chain 34 is selected so that conveyor 12 and conveyor 47 have exactly the same speed. On the other hand, when the electromagnetic clutch 33 is disengaged, the chain 6 drives the drive wheel 35 via the electromagnetic clutch 36 and the speed change gear 37. May be included. The speed change gear 37 may include either a mechanical gear, such as a five-speed gear, or a stepless hydraulic gear. When the transmission gear 37 is driven, the speed of the conveyor 47 will always be lower than the speed of the conveyor 12, and the transmission ratio will depend on the gear selected. One of the electromagnetic clutches 33 and 36 is ON
In other words, when one is connected, the other is always turned off. From the drive wheel 35 to the band, chain or gear transmission 4
Drive wheel 4 of unloading conveyor 48 by 1
2, the unloading conveyor 48 is driven by the drive wheel 42 via the electromagnetic clutch 43. The electromagnetic clutch 43 is always connected together with the electromagnetic clutch 33, and is always disengaged when the electromagnetic clutch 36 is ON or connected.

The drive motor 5 drives, via a band, chain, etc. 7 on an electromagnetic clutch 18, a band, chain, etc. 19 which drives a drive wheel 17 of the loading conveyor 11. On the other hand, the drive wheel 17 is connected to a drive wheel 15 driven by an adjustment motor 13 on an electromagnetic clutch 14 through drive means such as a band or chain. The adjustment motor 13 and the electromagnetic clutch 14 are controlled by a push button 49 which is pressed after the loading of the glass sheets onto the loading conveyor 11 is completed. The terminal end of the loading conveyor 11 is equipped with detection means 45, such as an optical eye or an electric eye, for detecting the leading and trailing ends of the glass sheets. As the glass sheets are transported through the furnace, this detection means 45 generates information regarding the length of the glass sheet or group of glass sheets being transported at a given time, and this information is sent to the microprocessor 8. . Based on this information and certain data previously sent based on the structural dimensions of the tempering device, the microprocessor 8 performs calculations as described below, and based on these calculations, the operation of the drive motor 5 and the electromagnetic clutch is controlled. be done. Additionally, this operational control includes a switch clock 9 which sets the heating time required by each type of glass plate before the glass plate is transferred to the furnace.
Requires. By the impulse generator 44,
Microprocessor 8 continuously monitors the distance traveled by drive motor 5.

The operation of the tempering device will be explained below.

While the preceding glass plate is being heated in the furnace 2, the subsequent glass plate, the length of which is indicated by l, is placed on the loading station L and the receiving button 49 is pressed.
When the electromagnetic clutch 14 is connected and the adjusting motor 13 is operated to move the glass plate by a distance A, the tip of the glass plate reaches the detection means 45. Next, the detection means 45 stops the adjustment motor 13 and switches the electromagnetic clutch 1.
Generates an impulse below 4. The glass sheets remain in this initial position on the loading conveyor 11 until the glass sheets in the furnace reach the cooling temperature determined by the period preset in the switch clock 9. Upon completion of this period, clock 9 generates a control impulse to activate electromagnetic clutches 18, 33, 4.
3 and energizes the drive motor 5 to a long conveyance stroke to move the glass plates placed on the conveyors 11, 12, 47 to the next conveyors 12, 47, 4, respectively.
8. The transmission ratio is selected such that each conveyor advances at the same speed during this transport stroke.

The electromagnetic clutch is actuated with the furnace conveyor 12 stopped.

The length of the transfer stroke B is adjustable by the operator and is set in the microprocessor 8, and this distance determines the point at which the leading edge of the glass plate stops in the furnace. Before describing the operation of the cooling unit and unloading station conveyors, the operation of the furnace conveyor 12 will be described. When the set transfer distance B is completed, the electromagnetic clutch 18 is disengaged and the reversible drive motor 5 reverses to stroke the glass plate.
Shake by X ₁ . The maximum oscillation speed is initially set to a predetermined conveying speed for a long conveying stroke, e.g.
It may be the same as 0.5 to 1 m/sec. Temporarily clock 9
If we call the heating time set to T, then 0.05−0.15
After xT time, this maximum speed may be reduced to a desired set rocking speed, for example 0.1 to 0.3 m/sec.

The symbol C designates the available effective inner length of the furnace, ie the distance between the leading and trailing edges of the glass pane at the end position of the rocking movement. The distance C can be adjusted by the operator and is set in the microprocessor 8 as a set value.

The microprocessor 8 is therefore able to calculate the swing length required by the length l of a given glass plate to be transported, based on the formula X ₁ =Cl.

The microprocessor 8 receives the length l of the glass plate from the detection means 45 as the glass plate is transported through the furnace. The microprocessor 8 controls the reversible motor 5 at the above speed and stroke length _X1 .

In order to move the glass plate from the furnace 2 to the cooling unit 4, the tip of the glass plate must always start from a certain point, so the microprocessor 8 operates at a set rocking speed (0.1 to 0.3 m/s). of,
After a time T, the tip of the glass plate is modified to such an extent that it is placed in the desired final retrograde position. This is the starting point of a long conveying stroke, from which the leading edge of the glass pane reaches a distance Z during the rocking movement. Therefore, Z=2×B−E [where, E
is a distance that can be set in the microprocessor 8 by the operator, and the extreme position of the tip of the glass plate is thereby adjusted in the cooling unit 3. The following description relates to a stage in which all conveyors are synchronous and at the same speed in a long conveying stroke. With the long conveying stroke performed until the total length l of the glass sheet entering the furnace has been measured, the microprocessor 8 calculates a new set point for the transmission gear 37 so that the transmission gear or The actuating means of the transmission 37 must be adjusted to the new value. The minimum time required for calculations and necessary adjustments is 3 seconds, with typical times being 4-5 seconds. Adjustment accuracy is approximately -20%
Therefore, stepwise adjustment is also possible. In order to adjust the speed change gear 37, the microprocessor 8 first controls the cooling unit conveyor 4.
The length of _the reciprocating motion X ₂ of determined as l ₂ . During this calculation process, the microprocessor calculates not only the length l of the glass plate in the furnace, but also the length l of the glass plate transported to the cooling unit, which has a length different from this length.
l ₂ must also be stored in the storage device. This is the basis of equipment for efficiently tempering a wide variety of small quantities of glass plates.

After this, the microprocessor 8 uses the formula k=X ₂ /
Calculate the transmission gear ratio from X ₁ . If the speed change gear is changed in stages, k becomes approximately this speed change ratio. After a long transport stroke, the electromagnetic clutches 18, 33, 43 are disengaged and the electromagnetic clutch 3
6 are connected and after this the microprocessor 8 determines the stroke length, which depends on the lengths of the glass plates l ₁ and l ₂ in the furnace and the effective length of the furnace and cooling unit, which are selected for optimal functionality. In order to swing the conveyors 12 and 47 by X ₁ and X ₂ , the electric motor 5 is moved back and forth, that is, in forward and reverse directions.

Although the present invention is described for simplicity as being placed in the loading station one glass sheet at a time, as is common when tempering small quantities of glass sheets, it is possible to It is also possible to arrange all of the glass plates in the maximum area L so that they move simultaneously as a group in the same way as one glass plate. In this case, in order to determine the total length of the group of glass plates, the microprocessor 8 selects the last pulse from the detection means 45 indicating the rear end of the glass plate, i.e. the last pulse within the maximum area L. The total length of the group of glass plates is determined in the same way as for one glass plate. The quality of the subsequent glass panes can be varied almost arbitrarily by the control device automatically controlling the conveyor to optimize its operation. When the quality of the glass sheets changes, the operator only needs to know the thickness of the glass sheets and set the predetermined heating time on the clock 9 for each glass sheet thickness.

An essential feature of the invention is that by using the variable speed gear 37, regardless of the difference in the effective length of the furnace and the cooling unit and the difference in the length of the succeeding glass panes,
The conveyors 12, 47 of the furnace and cooling unit are driven by a common electric motor 5 over the entire effective length of the furnace and cooling unit.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing a processing section and a driving section of a glass plate tempering apparatus of the present invention; and FIG. 2 is a block diagram of a driving section control device of the tempering apparatus shown in FIG. 1: Loading station, 2: Furnace, 3: Cooling unit, 4: Unloading station, 5: Drive motor, 6, 7: Chain, 8: Microprocessor, 9: Clock, 11, 12, 47, 48: Conveyor , 25: Fixed transmission device, 37: Speed change gear,
36, 33, 18, 43: Clutch.

Claims (1)

[Scope of Claims] 1. Contains in succession a loading station, a furnace, a cooling unit and an unloading station, each comprising a horizontal conveyor formed by a horizontal roller platform for supporting and transporting glass sheets on a horizontal surface,
a heating element in which the furnace defines a passage extending in the conveying direction, the ends of which have horizontal slits for passing the glass plate, and the furnace heats the glass plate to the softening temperature of the glass plate; operably connected to each of said conveyors and operated at predetermined intervals to transport glass sheets from said loading station to a furnace, from the furnace to a cooling unit, and from the cooling unit to an unloading station;
Furthermore, in the glass plate tempering apparatus including a furnace conveyor, a cooling unit conveyor, and a driving means for swinging and driving the glass plate during the conveyance cycle, the furnace and cooling unit conveyors 12, 47 are connected to the furnace. to either the conveyor of the cooling unit or the conveyor of the cooling unit via a speed change gear 37,
and a common drive motor 5 connected to the other via a fixed transmission device 25. 2 said drive motor 5 is connected to a transmission gear 37 by a first clutch 36 and a second clutch 3
3 directly connected to either the cooling unit conveyor 47 or the furnace conveyor 12, and the first
2. The apparatus of claim 1, wherein the conveyors of the furnace and cooling unit are driven synchronously at the same speed with the clutch 36 disengaged and the second clutch 33 engaged. 3 The drive motor 5 is connected to the loading conveyor 11 via the third clutch 18 and to the fourth clutch 43.
The third and fourth clutches 18 and 43 are connected when the first clutch 36 is disengaged and the second clutch 33 is connected, so that all the conveyors 11,
3. Apparatus according to claim 2, wherein 12, 47, 48 are driven synchronously at the same speed to move glass sheets over a distance B from one conveyor to another. 4 The drive motor 5 moves the predetermined transport distance B
4. The device according to claim 3, wherein the device is controlled by a microprocessor 8 configured with the following. 5. When the predetermined transport distance B reaches the end and the drive motor 5 is stopped, the microprocessor 8 connects the first clutch 36 and connects the second, third and fourth clutches 33, 1
8, 43, the drive motor 5 is rotated in the forward and reverse directions by a stroke length calculated according to a certain program, and the speed ratio of the speed change gear 37 is selected.
2 and 13, after the heating time preset in the control clock 9 has elapsed, the first clutch 36 is disengaged and the second, third and fourth clutches 33, 1 are disconnected.
5. The device according to claim 4, wherein the apparatus is driven synchronously at different stroke lengths X ₁ and X ₂ until 8 and 43 are connected to repeat a long conveying stroke. 6. The terminal end of the loading station 1 is provided with detection means 45 for transmitting information about the length l of the glass sheet entering the furnace to the microprocessor 8 during a long transport stroke, the microprocessor 8 Based on the length information, the length of the moving distance _of the glass plate moving back and forth in the furnace, X ₁ , can be calculated using the formula: 6. The apparatus according to claim 5, wherein the calculation is based on the distance between the furnace and the active inner length of the furnace, where l is the length of the glass plate. 7. The microprocessor 8 contains information regarding the lengths l ₁ , l ₂ of two successive glass plates, one located in the furnace and the other in the cooling unit, and thereby sets the settings for the transmission gear 37. To calculate the value, the basic formula X ₂ = D−l ₂ (where D
is the effective length of the cooling unit, and _l2 is the length of the glass plate inside the cooling unit.) After calculating the _length of movement of the glass plate moving back and forth in the cooling unit 7. The apparatus according to claim 6, wherein the apparatus is programmed to calculate the transmission ratio to be set on the transmission gear 37 from k=X ₂ /X ₁ . 8 When the speed change gear 37 is changed in steps,
8. The apparatus according to claim 7, wherein the gear ratio k is the gear ratio of the nearest step.