JPH0671636B2 - Leaf spring manufacturing apparatus and leaf spring manufacturing method - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a leaf spring manufacturing apparatus and a leaf spring manufacturing method applied to, for example, a vehicle suspension leaf spring.

[Prior Art] As an example of an apparatus for manufacturing a plate thickness changing material whose plate thickness changes in the longitudinal direction such as a tapered leaf spring, Japanese Patent Publication No. 58-572.
The device disclosed in Japanese Patent No. 7 is known.

The above-mentioned prior art continuously rolls a long rolling material in the length direction, while rolling in the width direction and rolling in the plate thickness direction to continuously form a desired plate thickness varying material. After molding, the product is cut into a predetermined product length. In this type of conventional apparatus, it is necessary to always keep track of the longitudinal position of the material to be rolled that moves continuously with rolling, and as a means therefor, a detection roller (pinch roll) is used.
Has been adopted. The detection roller rolls on the surface of the material to be rolled and rotates as the material to be rolled moves. Therefore, the length of the material to be rolled is measured in the longitudinal direction by detecting the amount of rotation of the detection roller by the encoder.

[Problems to be Solved by the Invention] In the case of the above-mentioned prior art, a long continuous 1
A plurality of products are continuously molded from the material of the book. Therefore, it is necessary to cut the long material after rolling into a predetermined product length. In this case, in order to perform cutting while moving the long material, the cutter must be cut in synchronization with the movement of the long material, which complicates the structure and control of the cutting device. Further, since the detection roller causes a measurement error due to the influence of thermal expansion, special measures are required to correct this. Moreover, it is considered that the detection roller may slip on the surface of the material to be rolled, and even from this point, there remains a problem in product accuracy. Then, the error of the cutting position may be accumulated.

Further, as seen in Japanese Patent Publication No. 59-35701, in a rolling device in which a tip of a material to be rolled is grasped by a chuck and a material to be rolled is pulled out from a rolling roll by using a pulling device that pulls the chuck, A means for measuring the rolling length by detecting the amount of movement by a length detector has also been proposed. However, in this case, the structure of the chuck portion that is driven to open and close by the hydraulic cylinder becomes complicated, and the material to be rolled is forcibly pulled out from the rolling roll by the chuck, so if the location pulled by the chuck is extended, the detection accuracy is adversely affected. Get out.

On the other hand, the long material after rolling may be taken out from the rolling line and cut into a predetermined length on another line, but in this case, in order to accurately specify the cutting position, shape measurement after rolling is performed. Must be done. For this reason, a shape measuring device is required separately, and work setup is increased.

When the rolling in the width direction and the rolling in the thickness direction are performed at the same time as in the prior art, tensile stress or compressive stress is generated in the material to be rolled between the width direction rolling roll and the thickness direction rolling roll. It is not preferable for leaf spring products.

Furthermore, when continuously rolling a plurality of products from one long material, the thermal expansion coefficient of the rolling roll changes with time, and the material temperature gradually decreases with the passage of time. The rolling load of the rolling roll changes,
It causes the plate thickness to vary. To address this issue,
The gap between the rolling rolls must be adjusted after rolling one product. However, in a device such as the above-mentioned conventional device in which rolling in the plate width direction and rolling in the thickness direction are performed at the same time in association with each other, the gap adjustment of the rolling rolls is extremely complicated, and practical application is difficult. Moreover, not only is the equipment large in size to carry out the heating / rolling process with the long material, but it is unsuitable for the production of a small number of lots. In addition, there is a problem that the material yield is poor because there is an unnecessary portion that has to be cut off at the cutting position between the leaf springs adjacent to each other. The above-mentioned prior art (Japanese Patent Publication No. 59-35701)
When gripping the end of the material to be rolled with a chuck and rolling as described above, the end cannot be rolled,
There is a case where a step of cutting off the end portion is required after rolling. Therefore, not only the number of steps is increased, but also the material yield is deteriorated. Further, unless the ends are cut accurately, the accuracy of the product deteriorates.

Therefore, it is an object of the present invention to manufacture a leaf spring having a desired length such as a taper leaf spring of which the thickness or width changes by a relatively easy control with a good yield and one by one.
Another object of the present invention is to provide a leaf spring manufacturing apparatus and manufacturing method capable of accurately measuring the rolling length without employing a complicated structure such as a chuck mechanism.

[Means for Solving the Problems] A manufacturing apparatus of the present invention developed to achieve the above-mentioned object includes at least a pair of rolling rolls, a rolling-down means capable of adjusting a distance between these rolling rolls, and a material to be rolled. In the state before rolling, the tip is advanced to a predetermined reference position between the pair of rolling rolls, and after the rolling is started, the material to be rolled is moved along with the forward movement of the material to be rolled sent out from the rolling roll. The movable contactor that is moved by the material while being pushed by the material, and the movable contactor is pressed toward the tip surface of the material to be rolled with a force that does not hinder the forward movement of the material to be rolled sent out from the rolling roll. And a pair of rolling rolls, an urging means for keeping the movable contactor in constant contact with the tip surface of the material to be rolled, a movement amount detection means for detecting the movement amount of the movable contactor from the reference position. Among The reduction amount detector that outputs a signal corresponding to the distance, and the setting data regarding the product shape to be rolled are input in advance, and the setting data and the signal fed back from the reduction amount detector and the movement amount detection means are input. A controller for controlling the rolling-down means so that a product having a desired shape can be obtained.

[Operation] In the leaf spring manufacturing apparatus of the present invention, when the rolling by the rolling rolls is started, the tip end surface of the material to be rolled abuts on the movable contactor when it passes through the gap between the rolls that influences the shape after rolling. After that, the movable contact moves to the downstream side together with the tip surface of the material to be rolled. Since the movable contactor moves following the forward movement of the material to be rolled, no force that stretches the material to be rolled is generated. Moreover, relative slippage with the material to be rolled does not occur. The moving amount of the movable contact is detected by a moving amount detector such as an encoder, so that the longitudinal position of the rolled material after rolling is tracked. The distance between the rolling rollers by the rolling-down means is controlled by the signal indicating the longitudinal direction position of the material to be rolled thus measured and the setting data input to the controller in advance, and a product having a desired shape can be obtained. Since the movable contact in the present invention is biased by the biasing means in the direction of pushing back the material to be rolled with a constant force, after the rolling pass for one time is completed, the movable contactor is moved to the original position, that is, movable. The tip of the contactor returns to a position where it enters between the rolling rolls. Further, even when the rolling is carried out by dividing into a plurality of passes as necessary, the material to be rolled and the movable contact can be pushed back to their original positions by the urging means each time one pass is completed.

In the method of the present invention, the leaf spring is manufactured by the first rolling device for rolling in the width direction and the second rolling device for rolling in the thickness direction. The setting data relating to the strip width pattern input to the controller for the first rolling mill is the product when the intermediate product rolled by this first rolling mill is rolled by the second rolling mill to the desired plate thickness. It is a value calculated back by taking into consideration the elongation and width expansion by rolling so as to obtain a desired strip width.

In the device of the present invention, the short material for one leaf spring is rolled one by one, and the rolling in the plate thickness direction is performed separately after the rolling in the plate width direction is completed. Therefore, each rolling process is simple, and ,
Since the rolling mill itself can also be driven by a simple control method, the reliability in terms of equipment operation can be improved and the equipment running cost can be reduced. Also, the reliability of the quality of the product after rolling is improved.

In the apparatus of the present invention, the leaf springs are rolled one by one, so that the roll gap can be easily corrected in order to prevent the reduction of the rolling accuracy due to the thermal expansion of the rolling rolls. That is, if the roll gap is corrected by a necessary amount when the rolling of one leaf spring is completed, the next leaf spring can be rolled with the correct roll gap. By repeating such gap adjustment at appropriate timing until the roll temperature reaches the equilibrium state and the thermal expansion converges, stable product accuracy can be maintained.

Also, if the rotation speed of the rolling rolls can be adjusted, it is possible to carry out variable speed rolling such that a taper portion with a steep rolling gradient is rolled at a low speed and a taper portion with a gentle rolling gradient is rolled at a high speed. Yes, in this case, it leads to reduction of power, improvement of productivity and improvement of product accuracy.

[Embodiment] An embodiment of the present invention will be described below with reference to FIGS. 1 to 7. FIG. 1 shows a schematic configuration of a first rolling apparatus 1 for rolling in the sheet width direction, and FIG. 4 shows a schematic configuration of a second rolling apparatus 2 for rolling in the sheet thickness direction. The basic structure of these two rolling devices 1 and 2 is generally common.

First, the first rolling device 1 will be described. The rolling apparatus 1 includes a pair of rolling rolls 10 and 11 for rolling a material A to be rolled, which is a material of a leaf spring, in the width direction. The rolling rolls 10 and 11 are rotatably supported by a rolling mill stand via a chock (not shown), and can be rotated by a roll driving means 12 in the direction of the arrow shown in the figure. The roll driving means 12 is configured to include, for example, a motor 13 and a speed reducer 14. As shown in FIG. 2, the rolling rolls 10 and 11 are arranged so as to perform rolling in a state in which the width direction of the material A to be rolled is set upright (so-called edge standing state). If the rolling is performed in such a posture, there is no possibility that the scale peeling from the material A to be rolled during the rolling is bitten by the rolling rolls 10 and 11. Grooves 15 and 16 for restricting the plate thickness of the material A to be rolled are provided around the outer circumferences of the rolling rolls 10 and 11.

Further, a rolling-down means 20 capable of adjusting the distance (roller gap) between the rolling rolls 10 and 11 is provided. The pressure reducing means 20 in the illustrated example includes hydraulic servo cylinders 21 and 22, servo valves 23 and 24 that move the hydraulic servo cylinders 21 and 22, hydraulic servo controllers 25 and 26, and the like. Servo valve 23, 24
Is controlled so as to adjust the reduction amount of the rolling rolls 10 and 11 based on the drive signal sent from the hydraulic servo controllers 25 and 26.

The hydraulic servomotors 21,22, as an example of the reduction amount detector for grasping the roll gap of the rolling rolls 10,11,
Detectors 27 and 28 using a differential pressure transformer or a magnet scale are provided. The detectors 27 and 28 detect the displacement amount of the rods of the hydraulic servo cylinders 21 and 22.

A movable contact 30 is provided on the downstream side of the rolling rolls 10 and 1. The movable contact 30 is pressed by the urging means 31 toward the gap between the rolling rolls 10 and 11. An example of the urging means 31 is a belt 34 wound around pulleys 32 and 33.
And a joint portion 35 for connecting the movable contact 30 to the belt 34, an air motor 36 for applying a torque to the pulley 32 so that the movable contact 30 is pressed in the above direction, and the like.

As shown in FIG. 3, the tip 37 of the movable contact 30 has the tip of the rolling roll 1 in the state before the rolling of the material A to be rolled starts.
It has entered the reference position within the gap between 0 and 11. The reference position here is, for example, on the line segment x that passes through the centers of the rolling rolls 10 and 11. Therefore, this movable contact 30
Is kept waiting until the tip 37 is positioned on the line segment x until just before rolling. The contact 30 is urged by the air motor 36 in the direction opposite to the moving direction of the material A to be rolled,
Since the urging force is smaller than the moving force of the material A to be rolled, after the rolling is started, it is pushed back by the tip surface of the intermediate product A ₁ delivered from the rolling rolls 10 and 11. Therefore, the end surface 37 of the movable contact 30 is kept in contact with the end surface of the intermediate product A ₁ at all times, and moves together with the intermediate product A ₁ .

Moving amount detecting means for detecting the amount of displacement of the movable contact 30
40 is a wire rope 43 wound around pulleys 41 and 42,
The wire rope 43 is provided with a joint portion 44 that connects the movable contact 30 and a detector 45 such as a rotary encoder that detects the amount of rotation of the pulley 41. In addition,
A linear motion detector such as a magnet scale may be adopted instead of the encoder.

The output signal of the detector 45 is input to a CNC (Computer Numerical Controller) 48. This controller 48
Sends a drive signal to the hydraulic servo controllers 25 and 26 described above. Numerical data regarding the plate width pattern as shown in FIG. 6 is input to the CNC controller 48.

On the other hand, the second rolling device 2 shown in FIG.
Intermediate product A ₁ rolled in the sheet width direction by the rolling device 1 of
, A pair of rolling rolls for rolling in the thickness direction
Includes 60,61. The rolling rolls 60, 61 are rotatably supported by a rolling mill stand via a chock (not shown), and can be rotated by a roll driving means 62 in the direction of the arrow shown. The roll driving means 62 includes a motor 63, a speed reducer 64 and the like. As shown in FIG. 5, the rolling rolls 60 and 61 are arranged so that the intermediate product A ₁ is rolled in a horizontal state.

The rolling-down means 70 capable of adjusting the roll gap between the rolling rolls 60 and 61 includes hydraulic servo cylinders 71 and 72 and servo valves 73 and 74.
And hydraulic servo controllers 75, 76, etc.

The hydraulic servo cylinders 71, 72 are provided with reduction amount detectors 77, 78 for grasping the roll gap of the rolling rolls 60, 61.

A movable contact 80 is provided on the downstream side of the rolling rolls 60 and 61. The movable contact 80 is pressed by the urging means 81 toward the gap between the rolling rolls 60 and 61. The biasing means 80 includes a belt 84 wound around pulleys 82 and 83,
Joint part 85 that connects the movable contact 80 to this belt 84
The pulley so that the movable contactor 80 is pressed in the above direction.
The air motor 86 for giving torque to the 82 is provided.

The tip 87 of the movable contactor 80 enters the reference position of the gap between the rolling rolls 60 and 61, that is, the roll center or a position close to this, before the rolling of the intermediate product A ₁ is started. The contact 80 is biased by the air motor 86 in the direction opposite to the moving direction of the product A ₂ after rolling,
Since the urging force is smaller than the moving force of the product A ₂ ,
After the rolling is started, it moves with the product A ₂ while being pushed back by the tip surface of the product A ₂ delivered from the rolling rolls 60, 61.

Moving amount detecting means for detecting the amount of displacement of the movable contact 80.
90 is a wire rope 93 wound around pulleys 91 and 92,
The wire rope 93 is provided with a joint section 94 for connecting a movable contact, a detector 95 such as a rotary encoder for detecting the rotation amount of the pulley 91, and the like.

The output signal of the detector 95 is input to the CNC controller 98. The controller 98 sends a drive signal to the hydraulic servo controllers 75 and 76, and also receives, for example, numerical data regarding the plate thickness pattern as shown in FIG.

The two controllers 48 and 98 described above may be incorporated in a computer integrated with each other. Further, the reduction means 20 and 70 are not limited to those shown in the figures, but a combination of a servo motor with a ball screw, an electric / hydraulic pulse motor with a ball screw, or a servo motor with an eccentric cam. A combination or the like may be adopted. Further, the reduction amount detector 27, 28, 77, 78 may be one that measures the distance between a pair of chocks supporting the rolling rolls 10, 11, 60, 61, or of the rolling rolls. A detector that directly detects the position may be used so that the amount of reduction can be measured more accurately. Further, by using an air cylinder instead of the air motors 36 and 86, the movable contacts 30 and 80 may be linearly moved back and forth. Alternatively, a combination of an electric motor and an electromagnetic powder clutch may be adopted. In short, biasing means 31,8
1 is the movable contactor 30,8 that is in contact with the end surface of the rolled product A ₁ , A _2.
0, as long as it fulfills the power of relief function to move lost the moving force of the product A _1, A _2, together with the end face of the product A _1, A _2.

Next, the operation of the leaf spring manufacturing apparatus provided with the rolling devices 1 and 2 will be described.

The material A to be rolled is previously cut into a length corresponding to one leaf spring. That is, the material A to be rolled has a longitudinal dimension after rolling that is the same as the length of the final product, or the end surface of the final product is processed, taking into consideration the elongation and width expansion of the material rolled by the rolling devices 1 and 2. It is cut in advance to a dimension that has been calculated back so that there is a margin that can be used. The material A to be rolled is heated by a heating furnace (not shown) to a temperature suitable for the hot rolling process.

FIG. 6 shows an example of the plate width pattern setting shape of the intermediate product A ₁ rolled in the plate width direction by the first rolling device 1. The data regarding the strip width pattern is input to the CNC controller 48 that controls the first rolling mill 1. For example, the positions l _{1 to} l _N , l of each part of the intermediate product A ₁ from the longitudinal reference plane l ₀
Dimension B ₁ .about.B _N in the width direction at a location corresponding to the _F, B _F is inputted in advance to the controller 48. This plate width pattern is obtained in consideration of the elongation and width expansion of the product by rolling so that the intermediate product A ₁ can be expanded to a predetermined product width when the intermediate product A ₁ is rolled to the following thickness by the second rolling device 2. is there.

FIG. 7 is an example of the plate thickness pattern setting shape of the leaf spring product A ₂ rolled in the plate thickness direction by the second rolling device 2. The data regarding the strip thickness pattern is input to the CNC controller 98 that controls the second rolling mill 2. For example, the position of each part from the lengthwise reference plane L _{0 of} leaf spring product A ₂
Dimensions in the thickness direction at locations corresponding to L _{1 to} L _N and L _F t _{1 to} t
_N and t _F are input to the controller 98 in advance.

In the present embodiment, the setting data in which the deviation between the above-mentioned set shape and the product shape caused by variations in the rigidity of the rolling mills 1 and 2 and the like is foreseen is input to the controllers 48 and 98. However, by inputting the product shape as it is into the CNC controller 48, 98, a program that automatically calculates the command values of the rolling shape in the width direction and the rolling shape in the thickness direction inside the controller 48, 49 is created. It may be assembled.

In the first rolling apparatus 1, when the rolling rolls 10 and 11 start rolling the material A to be rolled in the plate width direction, the movable contactor that has been waiting at the gap between the rolling rolls 10 and 11 until then. The tip end 37 of 30 is moved rightward in the figure while being pressed by the tip end surface of the intermediate product A ₁ after rolling sent out from the rolling rolls 10 and 11. The moving amount of the movable contactor 30 at this time is detected by the detecting means 40, and is input to the controller 48, and based on the plate width pattern set value previously input to the controller 48, the hydraulic servo cylinders 21 and 22. Is driven. Further, a signal related to the actual reduction amount detected by the reduction amount detector 27, 28 is fed back to the hydraulic servo controllers 25, 26, and the hydraulic servo cylinders 21, 22 are moved in the direction in which the deviation from the set value is eliminated.
Is controlled. In this way, the intermediate product A ₁ having a predetermined plate width pattern is rolled. After the intermediate product A ₁ after the rolling is discharged, the movable contact 30 is returned to the gap between the rolling rolls 10 and 11 again, and one cycle is completed.

It should be noted that due to the constraint of the biting conditions of the rolling rolls 10 and 11,
If the desired width cannot be rolled in a single pass, the movable contact 30 is used to push back the intermediate product A ₁ to the inlet side of the rolling rolls 10 and 11, and the rolling can be performed again by rolling again. It is possible to roll by rolling, and it is possible to easily deal with products that require a large reduction amount.

The intermediate product A _{1 that} has been rolled to a predetermined strip width through the above strip width rolling process is immediately sent to the second rolling device 2,
The rolling process in the thickness direction is performed by the rolling rolls 60 and 61. In the second rolling device 2, rolling rolls 60, 6
When the rolling of the intermediate product A 1 by ₁ is started, the tip 87 of the movable contactor 80, which has been waiting in the gap portion of the rolling rolls 60 and 61 until then, is sent from the rolling rolls 60 and 61 after the rolling. The leaf spring product A ₂ is moved to the right in the figure while being pushed by the tip surface of the leaf spring product A ₂ . The moving amount of the movable contactor 80 at this time is detected by the detecting means 90 and is input to the controller 98, and based on the plate thickness pattern set value previously input to the controller 98, the hydraulic servo cylinder 7
1,72 are driven. In addition, the signal related to the actual reduction amount detected by the reduction amount detector 77, 78 is fed back to the hydraulic servo controllers 75, 76, and the hydraulic servo cylinders 71, 72 are controlled in the direction in which the deviation from the set value is eliminated. It In this way, leaf spring products with a specified thickness and width
A ₂ is rolled. After the product A ₂ after the rolling is discharged, the movable contact 80 is returned to the gap between the rolling rolls 60 and 61 again, and one cycle is completed.

It should be noted that due to the restrictions due to the biting conditions of the rolling rolls 60, 61, 1
If the desired sheet thickness cannot be rolled in a single pass, the movable contact 80 is used to push the product A ₂ back to the inlet side of the rolling rolls 60, 61, and if rolling is performed again, it can be divided into multiple passes. It is possible to perform rolling in the plate thickness direction.

According to this embodiment using the rolling devices 1 and 2, after the rolling of the material A to be rolled in the plate width direction is completed, the obtained intermediate product A ₁ is rolled in the plate thickness direction. Therefore, complicated tensile stress and compressive stress do not occur in the rolled material A and the intermediate product A ₁ during rolling. Then, a predetermined product shape can be surely obtained only by performing a simple shape pattern setting.

Further, since the products A ₁ and A ₂ are rolled one by one, there is no possibility of accumulating rolling errors as seen when continuously rolling a long material.

Since the movable contacts 30 and 80 used to detect the amount of movement of the material A to be rolled and the intermediate product A _{1 in} the longitudinal direction enter near the center of the gap between the rolling rolls 10 and 11 and between the rolling rolls 60 and 61, The control range is wider than the movement amount detecting means using the conventional detection roller, and the measurement error due to slippage and thermal expansion unlike the detection roller does not occur.

In addition, when performing terminal processing etc. of product A ₂ after rolling,
Since processing can be performed based on the distance from the tip end surface of A ₂ , it is easy to position the processed part.

The present invention can of course be applied to the rolling of a leaf spring product A ₄ having an asymmetrical shape in the lengthwise direction as illustrated in FIG. 8, or the cantilever type leaf spring A ₅ shown in FIG. In addition, the present invention can also be applied to one-side taper-shaped rolling in which the plate thickness gradually decreases from the fixed end side to the free end side.

Further, as in the leaf spring A ₆ shown in FIG. 10, it is possible to form the tapered portions in the vicinity of both end portions over the predetermined lengths L ₁ and L ₂ and leave the other portions with the material thickness. It is possible. It is also possible to manufacture a leaf spring product in which the plate thickness is the same in the longitudinal direction and the plate width changes.

EFFECTS OF THE INVENTION According to the present invention, leaf springs having a desired width and thickness can be produced one by one, and the cutting position after rolling that causes a problem when continuously producing a plurality of leaf springs is improved. No setting is required, and the gap between rolling rolls due to thermal expansion can be easily adjusted.

In addition, a movable contactor that can enter the center of the rolling roll or a portion close to this is adopted, and this movable contactor is pressed by the urging means to the tip surface of the material to be rolled with an appropriate force. Since it moves passively with the advancing direction of the material to be rolled, while using a movable contactor with a simple structure, the absolute shape of the tip surface of the material to be rolled from the center of the rolling roll that directly affects the rolling shape is used. The position can be accurately grasped immediately after rolling. For this reason, the control range is wider than the length measuring means using pinch rolls and the length measuring means based on the movement amount detection of the chuck that pulls the material to be rolled, and the reduction control is accurate without being affected by the moving speed of the material to be rolled. Can be done. In the case of the present invention, since the desired rolling can be started immediately from the tip of the material to be rolled, the entire length of the material to be rolled can be made into a product, and the case where the end portion of the material to be rolled is grasped by a chuck is used. No unrollable parts occur. Therefore, the step of cutting off the end portion is unnecessary, and the material yield is extremely high, and the number of man-hours is small, and a highly accurate product can be obtained. Further, it is possible to carry out a small-lot production in which products having different rolling shapes are manufactured one by one in order. Moreover, since the biasing means in the present invention constantly biases the movable contactor in one direction (direction of pushing back the material to be rolled) during rolling, after the rolling is completed, the biasing force by this biasing means is utilized. The movable contact can be returned to the initial position, and when rolling in multiple passes if necessary, the material to be rolled and the movable contact can be pushed back to the initial position, and special return means It is unnecessary.

According to the method of the present invention, since the cutting step after rolling is unnecessary, the temperature drop of the material to be rolled is small, and therefore the heat treatment after rolling can be carried out without any problem. Further, since the first rolling device for rolling in the plate width direction and the second rolling device for rolling in the plate thickness direction are separately installed, it is possible to freely select the posture of the material to be rolled during rolling. it can.

[Brief description of drawings]

1 to 7 show an embodiment of the present invention, and are a side view and a second view of a first rolling device for rolling in the width direction of FIG.
The figure is a front view of the rolling roll portion in the first rolling device,
FIG. 3 is a side view showing a state in which the movable contactor is standing by at a reference position, FIG. 4 is a side view of a second rolling device for rolling in the thickness direction, and FIG. 5 is a view of the second rolling device. A front view of the rolling roll portion, FIG. 6 is a plan view showing a strip width pattern shape, FIG. 7 is a side view showing a strip thickness pattern shape, and FIGS. 8 to 10 show examples of leaf spring product shapes, respectively. Each is a side view. 1 ... 1st rolling mill, 2 ... 2nd rolling mill, 10, 11
...... Rolling rolls, 20 ...... Rolling means, 25,26 ...... Controller, 27,28 …… Rolling amount detector, 30 …… Movable contactor, 40
...... Movement amount detection means, 48 …… Controller, 60,61 ……
Rolling rolls, 70 ... Rolling-down means, 75,76 ... Controller, 77, 78 ... Rolling-down amount detector, 80 ... Movable contactor, 90 ...
… Movement detection means, 98… Controller.

Claims (4)

[Claims] 1. At least a pair of rolling rolls, a rolling-down means capable of adjusting a distance between the rolling rolls, a tip portion having a thickness smaller than a gap between the rolling rolls, and a predetermined distance between the pair of rolling rolls. The tip moves to the reference position, its tip surface is brought into contact with the end surface of the material to be rolled, and the material to be rolled is sent out from the rolling rolls. And the movable contact to be rolled by pressing the movable contact toward the front end surface of the material to be rolled with a force that does not hinder the forward movement of the material to be rolled fed from the rolling roll. Urging means for constantly contacting the front end surface of the roller, moving amount detecting means for detecting the moving amount of the movable contact from the reference position, and outputting a signal corresponding to the distance between the pair of rolling rolls. Reduction amount A dispenser and setting data relating to the product shape to be rolled are input in advance so that a product having a desired shape can be obtained based on the setting data and the signals fed back from the reduction amount detector and the movement amount detecting means. 2. A leaf spring manufacturing apparatus comprising: a controller for controlling the rolling-down means. 2. The movable contactor stands by at a position where a tip of the movable contactor is located on a line segment passing through the centers of the pair of rolling rolls before rolling, and the moving amount is set with the position of the tip as a reference position. The leaf spring manufacturing apparatus according to claim 1, wherein the length measurement is performed by the detection means. 3. A first rolling device for rolling in the width direction a material to be rolled which has been cut and heated in advance to a length corresponding to one leaf spring, and a downstream side of the first rolling device. A method for manufacturing a leaf spring, which is arranged and hot-formed into a desired shape by using a second rolling device for rolling in the thickness direction, comprising the first rolling device and the second rolling device. Each of the rolling devices has at least a pair of rolling rolls, a rolling-down means capable of adjusting a distance between the rolling rolls, a thickness of a tip portion is thinner than a gap between the rolling rolls, and a predetermined value between the pair of rolling rolls. The tip moves to the reference position, its tip surface is brought into contact with the end surface of the material to be rolled, and the material to be rolled is sent out from the rolling rolls. From the movable contact and the rolling roll The movable contactor is pressed toward the tip surface of the material to be rolled by a force that does not hinder the forward movement of the material to be rolled out so that the movable contactor is always in contact with the tip surface of the material to be rolled. A biasing means, a movement amount detecting means for detecting a movement amount of the movable contact from the reference position, a reduction amount detector for outputting a signal corresponding to a distance between the pair of rolling rolls, and rolling should be performed. Setting data relating to the product shape is input in advance, and the rolling-down means is controlled so that a product having a desired shape can be obtained based on the setting data and the signals fed back from the rolling-down amount detector and the movement amount detecting means. A controller is provided, and the material to be rolled for one leaf spring is rolled by the first rolling device to obtain an intermediate product having a predetermined strip width pattern in which the strip width changes in the longitudinal direction. A method for manufacturing a leaf spring, in which the intermediate product is immediately fed into the second rolling device and rolled to obtain a product having a predetermined plate thickness and plate width. 4. The controller for the first rolling device for rolling in the width direction has a predetermined plate width when the intermediate product is rolled to a desired product plate thickness by the second rolling device. 4. The method for manufacturing a leaf spring according to claim 3, wherein setting data of a leaf width pattern having dimensions is input.