US3836325A

US3836325A - Apparatus for charging materials into vertical heating furnace

Info

Publication number: US3836325A
Application number: US00423797A
Authority: US
Inventors: S Nakamura; K Kato; A Matsufuji; M Tokushige
Original assignee: Mitsubishi Electric Corp; Nippon Steel Corp
Current assignee: Mitsubishi Electric Corp; Nippon Steel Corp
Priority date: 1973-12-11
Filing date: 1973-12-11
Publication date: 1974-09-17
Anticipated expiration: 1991-09-17

Abstract

In the vertical heating furnace of the bottom charge type having a lift to go up for charging a piece of to be-heated material, an apparatus for charging a piece of such material into the furnace, provided, for free vertical movement, with a cap for supporting the so charged piece of material by the engagement of the groove made on the bottom surface thereof with the tip of said piece of material.

Description

United States Patent 91 Nakamura et al.

APPARATUS FOR CHARGING MATERIALS INTO VERTICAL HEATING FURNACE Inventors: Shoji Nakamura; Akira Matsufuji;

Masahiro Tokushige; Kunihiro Kato, all of Kitakyushu, Japan Assignees: Nippon Steel Corporation;

Mitsubishi Electric Corporation, both of Tokyo, Japan Filed: Dec. 11, 1973 Appl. No.: 423,797

US. Cl 432/241, 13/33, 214/23, 266/5 A, 432/52, 432/123 Int. Cl. F27b 5/12 Field of Search 432/241, 243, 239, 253, 432/254, 5, 86, 93, 123, 121, 52; 13/33; 219/390, 391; 214/23; 266/27, 28, 4 B, 5 A

References Cited UNITED STATES PATENTS 4/1940 Hinsey 432/243 51 Sept. 17, 1974 2,269,595 1/1942 Miller 266/5 A 2,687,289 8/1954 Cline etal.

3,456,935 7/1969 Bornor 3,463,470 8/1969 Green et al. 432/241 FOREIGN PATENTS OR APPLICATIONS 806,618 12/1958 Great Britain 266/5 A Primary Examiner-John J. Camby Assistant Examiner-Henry C. Yuen Attorney, Agent, or Firm--Wenderoth, Lind & Ponack [5 7] ABSTRACT In the vertical heating furnace of the bottom charge type having a lift to go up for charging a piece of to be-heated material, an apparatus for charging a piece of such material into the furnace, provided, for free vertical movement, with a cap for supporting the so charged piece of material by the engagement of the groove made on the bottom surface thereof with the tip of said piece of material.

9 Claims, 8 Drawing Figures PAIENIEH sin H974 SHEET 2 BF 5 PAIENIEB SEP 2 1 m4 'SHEEI 3 OF 5 FIG. 6'

PAIENTEDSEP x 71m sum u or 5 85% $116528 Emma 0253 mumDOw mokowkwo P251 ZOCbDQmE PAIENIEusEP I mm sum 5 OF 5 I M .Qbgg

BACKGROUND OF THE INVENTION The present invention relates to an apparatus for charging materials into a vertical heating furnace, particularly to an apparatus for charging metal materials into the vertical heating furnace from its bottom through the ascension of a lift carrying such materials thereon.

Of the vertical heating furnace, there are available two types, that is, the type of charging to-be-heated materials from the top of the furnace (hereinafter referred to as the top charge type) and the type of charging such materials from the bottom of the furnace (hereinafter referred to as the bottom charge type). The furnace of the top charge type has a demerit of causing deep indentations on the heated materials as defects of product as a result of the use of a tongue crane for suspending the material, and another demerit of possible slipping of a material from the crane. Thus, there has been the preference of the furnace of the bottom charge type, into which a to-be-heated material is charged as it is placed on a lift, whereby having no problems such as indentations made on the heated materials. However, there has not yet been used any such device as a guide with the furnace of the conventional bottom charge type that may prevent a material from leaning, so that there happened frequently the leaning of the material, particularly, such material that cannot stand by itself, resulting in the distortion of the induction coil or even in the breakage of the furnace.

No conventional vertical heating furnaces of either type have any device for guiding the charged material to the centeral part of the furnace, so that a material is charged in the furnace in an eccentric state, causing the heating of ununiform temperature distribution between both sides of the material, which results in a variance of qualitys over parts of the so made product.

SUMMARY OF THE INVENTION An object of the present invention is to provide an apparatus for charging to-be-heated materials into the vertical heating furnace provided with a material supporting cap, thereby ensuring the safety of heating operation of such materials.

Another object of the present invention is to provide an apparatus for charging to-be-heated materials to the central part inside the vertical heating furnace, so that such materials of whatever sizes may be heated with uniform temperature distribution. A further object of the present invention is to provide an apparatus for charging to-be-heated materials into the vertical heating furnace, including a material rotation device for ensuring the insertion of a material to the central part inside the furnace through the pushing of the material at constant pushing force.

A still further object of the present invention is to provide an apparatus for charging to-be-heated materials into the vertical heating furnace, including a material lifting device for absorbing shock given to the material supporting cap at impact with a material, thereby preventing the breakage of said cap.

The abovementioned objects, plus other objects of the present invention will be made clearer by reference to the below-given detailed descriptions and embodiments.

In order to achieve all the abovementioned objects, the apparatus according to the present invention for charging to-be-heated materials into the vertical heating furnace of the bottom charge type having a lift to go up for charging a material thereinto, is characterized by being provided, for free vertical movement, with a cap for supporting a charged material by the engagement of the groove made on the bottom surface thereof with the tip of said material.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side view, partly broken away, of an apparatus of the present invention for charging materials into the vertical heating furnace.

FIG. 2 is a plan view of the apparatus of FIG. 1 taken on the line II II. and from above.

FIG. 3 is a cross-sectional view of the apparatus of FIG. 2 taken on the line III III, to show a material push device of slide type and a truck driving device.

FIG. 4 is a side view of one embodiment of the control system for a material lifting device of the present invention.

FIG. 5 is a block diagram of the driving system of the material lifting device of FIG. 4.

FIG. 6 is a graph of the speed patterns of said material lifting device.

FIG. 7 is a side view of another embodiment of the control system for said material lifting device.

FIG. 8 is a block diagram of the driving system of the material lifting device of FIG. 7.

DESCRIPTION OF THE PREFERRED EMBODIMENT The following is detailed description of an embodiment of the apparatus of the present invention for charging material into the vertical heating furnace, using steel slabs as to-be-heated material.

In FIG. 1, the vertical heating furnace 1 has a charging inlet 2 for charging a slab s on the bottom surface. In the furnace wall 3, there are inlaid induction coils for the induction heating of the slab s.

The slab lifting device 11 consists of a lift 12 and a driving device for the slab lift 17, and is set below the charging inlet 2 of said vertical heating furnace 1. The lifting frame 13 of the lift 12 may take whatever shape is appropriate like a column; the center line of the heating furnace 1 and that of the lifting frame 13 of the lift 12 are on one and the same line extending perpendicularly to the floor. On the top of the lifting frame 13 of the lift 12, there are provided a slab support 14 for supporting the slab S. In the upper part of the lifting frame 13 of the lift 12, there is set a cover 15 for covering the charging inlet 2; and the middle part of said lifting frame 13 is guided by guide rollers 16. The driving device 17 for the slab lift comprises a hydrolic cylinder 18, and is set upright in the pit 20 made in the floor. The tip of the rod 19 of the hydraulic cylinder 18 is connected the with lifting frame 13 of the lift 12; and by the action of the hydraulic cylinder 18, the lift 12 is raised from its lowest position, so that the slab support 14 is accordingly raised from nearly the same level as of a transfer roller table 9 to somewhat above the charging inlet 2. As for the shape of the lifting frame 13 of the lift 12, it should not be limited to a column, but can be a square rod or a frame. Besides a hydraulic cylinder, a compressed air cylinder or even an electric motor can be used for the driving device 17 for the slab lift.

The slab S is transferred from the transfer roller table 9 to the below-mentioned slab delivering device 31, and then taken by the lift 12 to be charged into the heating furnace 1. In order to prevent damage of the furnace wall or other parts of the furnace caused by the leaning of the slab S as this is pushed up by the lift 12, the tip of the slab S is held firm by the supporting cap 21. Referring to FIG. 1, there are provided on the furnace wall, guide 24 of an appropriate shape, facing each other extending from the ceiling of the furnace chamber to the vicinity of the charging inlet 2 along the front inner wall and the rear inner wall of the furnace l. The lower ends of the guide 24 extend to the stoppers 25 projected into the furnace; The supporting cap 21 comprises a block'having a groove 22 open downward. The cross-section of the groove 22 forms a trapezium, so that it can be engaged with the tip of the slab S, with a considerably large allowance given to the thickness of the slab S. On both side of the supporting cap 21 there are provided projections or grooves of an appropriate shape for guiding lengthwise on the cap, and these are engaged with the guiding device 24 provided on the furnace wall, so that the supporting cap 21 is made possible to go up and down, guided by these guiding devices 24. Two guiding devices 24. and one supporting cap 21 combine to fonn one set; and there are two sets of such combination arranged each near each side-wall of the heating furnace 1, that is, these face each other in the perpendicular against the surface of the drawing of FIG. 1. The material of the supporting cap 21 should be such that is not subjected to heating by the induction coils 4, but be heat resisting and high strong. Therefore, the supporting cap 21 is made of a refractory material or a combination of a metal and a refractory material.

The following is description of the slab delivering device 31 for delivering slabs from the transfer roller table 9 to the slab lifting device 11 which is constructed as mentioned above.

As shown in FIG. 1 and FIG.-2, there is provided a truck 32 running toward the transfer roller table 9 and backward (to the left side and the right side on the drawing). Said truck 32 is constructed with three

frames

33, 34 and 35, these forming a U-letter, when viewed from above. The

frames

34 and 35 are equipped with wheels 37 to run on the rails 36 bridging over the pit '20. The rear part of each of the

frames

34 and 35 is supported by a roller 39 set'for free rotation on the bearing stand 38. Said lift 12 runs perpendicularly through the space enclosed by the

frames

33, 34 and 35 On the floor between the

frames

34 and 35 of the truck 32 there is fixedly set a rnotor40. A driving shaft 41 having a pinion 42 at each of both ends, extends toward opposite directions from the motor 40. These pinions 42 are engaged respectively with racks 43 provided on the upper surface, respectively, of the

frames

34 and 35. Thus, the truck 32 moves forward and backward on the rotation of the motor 40.

On both sides of the front frame 33 of the truck 32, there are provided a pair of stands 44 supporting a rotating shaft 45 for free rotation. On this rotating shaft 45 are fixed a pair of slab supporting-tilting arms 46 shaped like the letter L or of the shape similarthere to,

in a manner that they interpose the ascensiondescension course of the lift'12. On respective ends of the rotating shaft 45 are fixed the ends of the levers 48. On the upper surface of the

frames

34 and 35 there are fixed respective stands 51, each being provided'with an hydraulic cylinder 49 for free rotation on a pin 52. The tip of the rod 50 of these hydraulic cylinders 49 is connected, for free rotation, respectively, with the tip of said levers 48 by means of a pin 53. Therefore, the slab supporting-tilting arms 46 rotate on the action of the oil cylinders 49 within the range from the position to make the slab supporting surface 47 lie horizontally to the position to make said surface 47 stand perpendicularly.

Opposite to the slab supporting-tilting arms 46 are provided slab pushing devices 61 for pushing the back of the slab S against the slab supporting surface 47 of said slab supporting-tilting arms 46. Toward the rear part of the

frames

34 and 35 of the truck 32 and inside these frames, there are provided a pair of supporting frames 62 standing from the floor. On both ends of each of these supporting frames 62 are set a pair of bearing stands 63; and each of the bearing stands 63 has a pair of rollers 64 facing each other vertically for free rotation. A guiding sheath 65 is held by a set of the rollers 64 for free forward and backward movement. In each guiding sheath 65 is contained a pushing rod 66 for free forward and backward movement; and at the tip of the pushing rod 66 is fixedly set a pushing head 67 having rollers 68 for free rotation.

On the side of the guiding sheath 65 is provided a rack 69 along the long direction of the sheath 65. On the other hand, a rotating shaft 71 is set on each of said supporting frames 62; and at the top end of said rotating shaft 71 there is provided a pinion to be engaged with said rack 69; and at the bottom end thereof there is fixed a bevel gear 73 to be engaged with a bevel gear 72 set in the middle of the driving shaft 41 of said truck 32. Thus,the guiding sheath 65 starts moving on the rotation of the motor at the same time with the start of the motion of the truck 32, in the direction contrary to the moving direction of the truck 32. The driving device for the guiding sheathes 65 is not limited to the abovementioned, but may be used as to drive the guiding sheathes 65 freely and independently from the truck 32.

In the rear part of the guiding sheath 65 there is set hydraulic cylinder 75 for adjusting the pushing force of the slab S. The rod 76 of said hydraulic cylinder 75 is connected with the rear end of said pushing rod 66. With the hydraulic cylinder 75 is connected an hydraulic unit 78 through a pipe 77, which pipe has a pressure guage 79 and a relief valve 80 set on itself. Instead of such hydraulic cylinder 75, it is naturally possible to use an air pressure cylinder.

Furthermore, a slab guiding device 81 is provided right below the heating furnace 1. The device 81 consists of a pair of sets, each set comprising a horizontal frame 82 having a rotary frame 83 set, at its top end, for free rotation. At the top end of the horizontal frame 82 and the rotary frame 83 are set, respectively, the

guide rollers

84 and 85 for free rotation. With the rear end of the horizontal frame 82 is connected the tip of the rod 87 of hydraulic cylinder 86. On the lower surface of the horizontal frame 82 is fixed a hydraulic cylinder 88. Said hydraulic cylinder 86 is fixed on the body of the heating furnace 1 or at any other position.

In the middle of the rotary frame 83 is set one end of a lever 90 for free rotation. The other end of the lever 90 is connected with the tip of the rod 89 of said hydraulic cylinder 88.

The device consists of a pair of sets, each set comprising a horizontal frame 82, a rotary frame 83 and other members, as mentioned above, and is so arranged right below the charging inlet 2 that the

guide rollers

84 and 85 of one set face the corresponding rollers of the other set these sets being so disposed as to interpose the course of the slab S between them.

The so constructed slab charging apparatus according to the present invention, functions as follows:

After put out of the blooming mill, the slab S is sent on board the transfer roller table 9, to stop in front of the slab delivering device 31. By that time, the truck 32 has been close to the transfer roller table 9; and the slab supporting-tilting arms 46 have their supporting face 47 extended horizontally so as to enter between the transfer rollers 10; and the lift 12 is waiting for start at the bottom position. Push back the rods 50 of the hyfractory material. Though these materials are not inflammable for generating heat themselves, they will be heated by radiant heat from slabs S, reducing the shock resistance of refractory materials which is low even under normal conditions. Also, as the time for charging a slab S into the heating furnace and that for discharging it from the furnace require to be as short as possible from the standpoint of operation efficiency of the fur nace, the ascension speed of slab S is considerably high. Therefore, if the tip of the slab S contacts the supporting cap 21 or if the supporting cap 21 runs against the stopper 25, there be produced such a great shock that the supporting cap 21 may be broken, causing possible stop of operation.

draulic cylinders 49 in that situation, and the rotating shaft 45 rotates clockwise, making the slab supportingtilting arms 46 start standing up, as they take up the slab S from the transfer roller table 9.

Then, the truck 32 goes back to put the slab S right below the charging inlet 2. At that time, the guiding sheathes 65 advance as mentioned above, so that the pushing heads 67 push the slab S from the back against the supporting face 47 of the slab supporting-tilting arms 46.

Thus, put the hydraulic cylinder 18 into operation, so as to make the lift 12 go up. While supported by the slab supporting-tilting arms 46, the slab 5 is pushed up by the ascension of the lift 12, and charged into the heating furnace 1, as it is guided by the

guide rollers

84 and 85. As mentioned above, the slab S is pushed by the pushing heads 67 against the supporting face 47 of the slab supporting-tilting arms 46, so that the slab S will not slip out of the lift 12, when it is transferred from the slab supporting-tilting arms 46 to the lift 12, or in the course of its ascension. As the slab S is guided by the guide rollors 84 and 85 right below the charging inlet 2 before charged into the furnace chamber 5, it is easy toguide the slab S to the center of the furnace chamber 5. f

In the furnace chamber 5, the supporting cap 21 is situated at the bottom, so that the slab S comes up to have its top engaged with the groove 22 of the supporting cap 21. Then, in the furnace chamber 5, the slab S continuesgoing up with its tip supported by the supporting cap 21 which is going up guided by the guiding 24, until it has been completely housed in the furnace chamber 5.

When the heating of the slab S finishes, the lift 12 descends so as to take the slab S out of the furnace chamber 5. At that time, the supporting cap 21 descends together with the slab S, until it has stopped in collision with the stopper 25, when the top of the slab S is released from the groove 22. Then, the heated slab S takes the reverse course against that which was taken when it was charged, so that it is brought back onto the transfer roller table 9.

Then, embodiment of the control system for the slab lifting device is presented, as follows:

As mentioned above, the supporting cap 21 is made of a refractory material or of a metal together with a re- According to the present invention, this problem is so solved that just before the slab S runs against the supporting cap 21 or leaves it, the ascension of the slab S is decelerated, thereby reducing the shock produced against the supporting cap 21 by the collision with the slab S, for the prevention of breakage of the supporting cap 21. In FIG. 4, numeral 91 indicates a rack provided along the side of the lift 12 in its long direction. Said rack 91 is engaged with a pinion 92. Said pinion 92 is connected, through a clutch 93, with a reduction gear 94 and a control device 95, Said clutch 93 is to relay the action of the lift 12 to the reduction gear 94 and the control device 95 only when the tip of the slab S reaches any pre-set point m before the contact with the supporting cap 21; it is put-into operation in such way that a slab tip detecting device 98 made of a photoelectric tube or the like is provided at the preset point m, to issue a signal on the passage of the slab S, as follows:

The abovementioned control according to the present invention is made by converting the linear movement of the slab S from the passage at the present point m to the finish of its charging into the heating furnace or from the start of its discharging to the passage at the present point m, to a rotary movement thereof. The function of the reduction gear 94 is to make a rotary movement within 360, that is, the reduction gear 94 has such a reduction ratio that the shaft of the apparatus constituting the control device 95 may not turn a complete round. Inside the control device 95, there are set an acceleration-deceleration-point detector 96 and a speed setting device 97, both of which are made of limit switch LS, LS having different phases each other or proximity switches. The speed setting device 97 has a memory of speed patterns made by signals issued respectively from said limit switches. Said control device 95 is connected with a drive source 99, such as a hydraulic cylinder for operating the lift 12. The abovementioned may be presented for easy understanding in FIG. 5 with a block diagram.

The following is to explain the speed control according to the present invention by reference to FIG. 6:

In case of the ascension of the lift 12 for charging the slab S, the clutch 93 is off, until its tip reaches the present point m. When the tip reaches the point, a slab tip detecting device 98 using a photoelectric tube or the like, catches the passage of the tip, and issues a signal which puts the clutch 93 on, driving the control device 95 into operation.

As the slab S moves, signals are issued one after another from the limit switches in the order of LS LS LS, and LS which have their respective speed patterns that is, LS issues an instruction signal to the 99 for deceleration of the lift 12, L8 and LS for movement of the lift 12 at low speed; and LS, for acceleration of the lift 12 into the heating furnace. (See FIG. 6) In case of the descension of the lift 12, instruction signals are issued one after another from the limit switches in the order of L8,, LS LS and L8,, and when the ,tip of the slab S passes the present point m, the clutch 93 turns off, putting the control device 95 back into its state before operation. The period for operation at the fixed rate of low speed provided according to the present invention, is to make smoother the contact of the slab S with the supporting cap 21, irrespective of the difference in thickness and shape of slabs S; therefore, there are needed no restrictions regarding such period. As for a reduction gear and limitswitches, all these can be combined into one body, instead of the separation between the reduction gear and the limit switches according to the present invention.

FIG. 7 and FIG. 8 show an another embodiment of the control system for the slab lifting device.

In FIG. 7, numeral 101 indicates an accelerationdecceleration-pointdetector, which is'provided with limit switches LS LS operating respectively at different phases; and the lift 12 is provided with a striker 102 for putting these switches into operation. In this case, proximity switches or the like can be used instead of limit switches. A lift speed controlling device 104 is so constructed that signals issued from the limit switches of the acceleration-deceleration-point detector 101, are put intoa lift speed changer 103. The lift speed controlling device 104 is connected to the driving source 105, such as an oil cylinder, for ascension and descension of the lift 12. The abovementioned is illustrated for easy understanding in FIG. 8.

The following is to briefly explain the speed control according to the present invention by reference to FIG. 6: As the lift 12 passes the acceleration-decelerationpoint detector 101 in the course of ascension, signals are issued one after another from the limit switches in the order of L5,, LS LS and L8,, and are put into the speed changer 103 for instructing the driving source of LS, LS LS and L8,, issue instruction signals for controlling the speed of the lift 12 according to the speed patterns held by respective limit switches.

According to the present invention, the accelerationdeceleration-point detector 101, that is, the limit switch L5,, is set at such a place as to be convenient for starting operation when the tip of the slab S reaches the preset point m, which is set at any point for the tip of the slab S to pass before its contact with the supporting cap 21. But, as the stroke of ascension or descension from the starting point of the tip of the slab S to the preset point m (the starting point of acceleration or decelfurther regard to this example, the movement of the acceleration-deceleration-point detector 101 is converted into a rotation of the motor 106, and the position for stopping the motor 106, is controlled by using a pulse generator 108. For setting up the stroke of movement of the acceleration-deceleration-point detector, the width of the slab S may be put as it is, or after it has been converted by the automatic processing with other accessory equipment. In the latter case, automation of the total system will be made possible.

What is claimedis: I

1. An apparatus for charging to-be-heated materials into the vertical heating furnace, which comprises a material lift placed below the charging inlet made close to the bottom of the furnace and having a part at its top to support a piece of such material; a driving device for the material lift for the ascension and discension thereof; and a supporting cap provided within the furnace and guided by guiding members in its ascension and descension, having a groove open downward to be engaged with the tip of the material.

2. The apparatus claimed in claim 1, wherein the driving device for the material lift consists of a rack provided on the side of the long direction of the material lift; a pinion engaged with the racks; a reduction gear connected with the pinion through a clutch; an acceleration and deceleration point detector made of a plurality of switches to work at different levels in the lifting process of the material lift; a speed setting means having a memory of speed patterns for the lifting process of the material lift, so as to issue output signals in response to signals issued from said acceleration and deceleration point detector; a driving source for the material lift to work on receiving output signals issued from the speed setting means; and a material tip detecting device provided at a preset point on the ascensiondeccension course of materials to issue output signals to put on said clutch.

3. The apparatus claimed in claim 1, wherein said driving apparatus for the material lift consists of an acceleration and deceleration point detector having a plurality of switches arranged at a distance each other in the moving direction of the material lift to work in response to the operation of these switches put by a striker set on the material lift, said detector being movable in the ascension and descension direction of the material lift; a speed setting device having a memory of speed patterns for the lifting process of the material lift,

so as to issue output signals in response tosignals issued from said acceleration and deceleration point detector; and a driving source for the material lift to work on receiving output signals issued from the speed setting device.

4. The apparatus claimed in claim 1, wherein said supporting cap is made of a refractory material.

5. An apparatus for charging tQ-be-heated materials into the vertical heating furnace, which comprises a material lift placed below the charging inlet made close to the bottom of the furnace and having apart at its top to support a piece of such material; a driving device for the material lift for the ascension and descension thereof; and a supporting cap provided within the furnace and guided by guiding members in its ascension and descension, having a groove opendownward to be engaged with the tip of the material; and a material guiding device provided right below the charging inlet and having a pair of horizontal frames having rollers for free rotation so as to make the frames go freely forward and backward, such rollers being provided in such manner as to interpose the ascension and descension course of materials.

6. An apparatus for charging to-be-heated materials into the vertical heating furnace, which comprises a material lift placed below the charging inlet made close to the bottom of the furnace and having apart at its top to support a piece of such material; a driving device for the material lift for the ascension and descension thereof; and a supporting cap provided within the furmace and guided by guiding members in the ascension and descension, having a groove open downward to be engaged with the tip of the material; a truck framed so as to make a space inside to receive the material lift; a device for driving the truck forward and backward; material supporting-tilting arms set at the front part of the truck for free turn round, up and down, so as to take up a material from a material transportation device and to deliver it to the material lift; a driving device for the material supporting-tilting arms; a freely movable material pushing device having at its tip, pushing members with rollers, placed in opposition to the supporting face of the material supporting tilting arms when turning up; and a pushing pressure balancing device provided at the rear part of the material pushing device for making the pushing members push the material on the supporting face of the material supporting tilting arms with uniform distribution of pressure.

7. The apparatus claimed in claim 6, wherein said material pushing device consists of a guiding sheath held for free movement on a stand, provided with a rack on the side thereof in the long direction and connected with the driving device for said truck through pinion engaged with these rack, said guiding sheath being movable in the direction reverse to that of movement of said truck; and a pushing rod inlaid for free sliding-in the guiding sheath, with said pushing member provided at its tip.

8. The apparatus claimed in claim 6, wherein said pushing pressure balancing device consists of a hydraulic cylinder fixed at the rear part of said material pushing device, so as to work in connection with said pushing member; and a hydraulic unit connected with a hydraulic cylinder, so as to give required volume to the cylinder.

9. The apparatus claimed in claim 3, wherein said acceleration and decceleration point detector is set on a screw rod for free movement in the perpendicular direction on the rotation of the screw rod, said screwrod to be driven by a motor operating under control by a pulse generator having been supplied with the predetermined volume of movement of the acceleration and deceleration point detector.

Claims

2. The apparatus claimed in claim 1, wherein the driving device for the material lift consists of a rack provided on the side of the long direction of the material lift; a pinion engaged with the racks; a reduction gear connected with the pinion through a clutch; an acceleration and deceleration point detector made of a plurality of switches to work at different levels in the lifting process of the material lift; a speed setting means having a memory of speed patterns for the lifting process of the material lift, so as to issue output signals in response to signals issued from said acceleration and deceleration point detector; a driving source for the material lift to work on receiving output signals issued from the speed setting means; and a material tip detecting device provided at a preset point on the ascension-deccension course of materials to issue output signals to put on said clutch.

3. The apparatus claimed in claim 1, wherein said driving apparatus for the material lift consists of an acceleration and deceleration point detector having a plurality of switches arranged at A distance each other in the moving direction of the material lift to work in response to the operation of these switches put by a striker set on the material lift, said detector being movable in the ascension and descension direction of the material lift; a speed setting device having a memory of speed patterns for the lifting process of the material lift, so as to issue output signals in response to signals issued from said acceleration and deceleration point detector; and a driving source for the material lift to work on receiving output signals issued from the speed setting device.

5. An apparatus for charging to-be-heated materials into the vertical heating furnace, which comprises a material lift placed below the charging inlet made close to the bottom of the furnace and having a part at its top to support a piece of such material; a driving device for the material lift for the ascension and descension thereof; and a supporting cap provided within the furnace and guided by guiding members in its ascension and descension, having a groove open downward to be engaged with the tip of the material; and a material guiding device provided right below the charging inlet and having a pair of horizontal frames having rollers for free rotation so as to make the frames go freely forward and backward, such rollers being provided in such manner as to interpose the ascension and descension course of materials.

6. An apparatus for charging to-be-heated materials into the vertical heating furnace, which comprises a material lift placed below the charging inlet made close to the bottom of the furnace and having a part at its top to support a piece of such material; a driving device for the material lift for the ascension and descension thereof; and a supporting cap provided within the furnace and guided by guiding members in the ascension and descension, having a groove open downward to be engaged with the tip of the material; a truck framed so as to make a space inside to receive the material lift; a device for driving the truck forward and backward; material supporting-tilting arms set at the front part of the truck for free turn round, up and down, so as to take up a material from a material transportation device and to deliver it to the material lift; a driving device for the material supporting-tilting arms; a freely movable material pushing device having at its tip, pushing members with rollers, placed in opposition to the supporting face of the material supporting tilting arms when turning up; and a pushing pressure balancing device provided at the rear part of the material pushing device for making the pushing members push the material on the supporting face of the material supporting tilting arms with uniform distribution of pressure.

7. The apparatus claimed in claim 6, wherein said material pushing device consists of a guiding sheath held for free movement on a stand, provided with a rack on the side thereof in the long direction and connected with the driving device for said truck through pinion engaged with these rack, said guiding sheath being movable in the direction reverse to that of movement of said truck; and a pushing rod inlaid for free sliding in the guiding sheath, with said pushing member provided at its tip.

9. The apparatus claimed in claim 3, wherein said acceleration and decceleration point detector is set on a screw rod for free movement in the perpendicular direction on the rotation of the screw rod, said screwrod to be driven by a motor operating under control by a pulse generator having been supplied with the pre-determinEd volume of movement of the acceleration and deceleration point detector.