Rolling Apparatus

This application is a continuation of the International Application No. PCT/JP2024/030147, filed on Aug. 26, 2024, which claims the benefit of foreign priority to Japanese Patent Application No. 2024-061032 filed on Apr. 4, 2024, the entire contents of each of which are hereby incorporated by reference.

The present invention relates to a rolling apparatus that is used mainly for rolling threads and is capable of correcting a relative position of a fixed flat die thereof and a moving flat die thereof.

A device such as a rolling-pressure monitoring device disclosed in Patent Literature 1 has conventionally been known which monitors rolling pressures applied to base materials and thereby determines whether or not rolling has been performed appropriately.

Patent Literature 1: JP-A-2021-175576

In a rolling apparatus, the relative positions of a fixed flat die and a moving flat die are required to be precise. Specifically, the plastic deformation mark formed on the fixed flat die side and the plastic deformation mark formed on the moving flat die side need to coincide with each other. In particular, in thread rolling, when these plastic deformation marks are misaligned, the rolled product may be of no value as a finished product.

Conventionally, the correction of the positions of the fixed flat die and the moving flat die has depended in large part on the skilled person, and even so, multiple tests have had to be repeatedly carried out many times.

Therefore, an object of the present invention is to provide a rolling apparatus which facilitates an easy correction of the relative positions of a fixed flat die thereof and a moving flat die thereof.

A rolling apparatus according to the present invention, which includes a fixed flat die fixed on a base table and having a fixed-side rolling-surface section, and a moving flat die disposed reciprocally movable along a rolling direction on the base table, the moving flat die having a moving-side rolling-surface section opposite, during rolling processing, to the fixed-side rolling-surface section, includes:

In such a configuration, first, streaks are formed in a base material in a required region by using the test-movement control means, thereby producing a test piece in which such streaks are composed of fixed-side streaks and moving-side streaks. Then a positional deviation amount between the fixed-side streaks and the moving-side streaks, both formed in the test piece, is inputted by using the positional-deviation-amount inputting means. Then the correction-movement-amount calculation controlling means is used to calculate a correction movement amount to a position of the moving flat die where the appropriate position can be obtained. The thus-calculated correction movement amount is output by the adjustment-value outputting means. Based on this correction movement amount, the top-dead-center position adjusting means is used to adjust the position of the top dead center of the moving flat die such that the position of the top dead center is made appropriate for causing the moving-side streaks to coincide with the fixed-side streaks. Note that, as to how the predetermined movement amount is set for causing the base material to rotate a half turn for forming both streaks, the present invention has proposed a configuration in which the base material is rotated approximately a half turn. Specifically, such a configuration may be one in which the base material is rotated a half turn, may be one in which the base material is rotated slightly more than a half turn to the extent which the streaks do not become unmeasurable due to excessive overlap of the streaks, or may be one in which the base material is rotated slightly less than a half turn to the extent which the streaks do not overlap each other. The configuration is preferably one in which the base material is rotated slightly less than a half turn to the extent which the streaks do not overlap each other. Further, the rotary direction of the base material may be either forward or reverse.

Further, the opposing-position adjusting means is used to adjust the relative position between the fixed flat die and the moving flat die in the opposing direction such that the relative position in the opposing direction is set so as to provide an appropriate bite depth, based on the bite depths of the fixed-side streaks and moving-side streaks which all have been formed in the test piece, and the opposing position information of the fixed flat die and the moving flat die when these fixed-side streaks and moving-side streaks are formed. Here, since the bite depth determines the thread pitch and the rolling pressure (the pressure caused by the fixed flat die and the moving flat die while rolling processing), pitch alignment of the thread and optimization of the rolling pressure can be performed by adjusting the bite depth appropriately. This allows pitch alignment with high precision, which results in a reduction in occurrence of pitch-forming defects, and also allows rolling processing with an appropriate rolling pressure, which results in a reduction in occurrence of slipping during the rolling processing, leading to a reduced occurrence of forming defects due to the slipping. By optimizing the bite depth in this way, the probability of occurrence of forming defects in the rolling processing (hereinafter referred to as forming defect rate) can be reduced.

In this way, in the configuration according to the present invention, based on the fixed-side streaks and moving-side streaks formed in the test piece, the position of the top dead center of the moving flat die is adjusted and the relative position between the moving flat die and the fixed flat die in the opposing direction is also adjusted, thereby increasing the rolling accuracy of threads and reducing the forming defect rate. Then, in this configuration, it is possible to adjust the position of the top dead center of the moving flat die in accordance with the correction movement amount, and also to adjust the relative position in the opposing direction by using the opposing position information and the bite depth. As a result, these adjustments can be performed without relying on the experience or intuition of an operator, and the burden required for the adjustment work can be reduced. Therefore, threads can be stably formed in compliance with the desired product standards with high precision, and the threads of excellent quality can be stably manufactured.

In the rolling apparatus described above according to the present invention, a configuration is proposed in which the adjustment-value outputting means may be configured to execute a control content for displaying the inputted bite depth received by the bite-depth inputting means on a predetermined display section, and a control content for sequentially displaying the opposing position information on the display section in accordance with the position adjustment of the moving flat die in the opposing direction by the opposing-position adjusting means.

In such a configuration, the opposing-position adjusting means may be used to adjust the relative position between the fixed flat die and the moving flat die in the opposing direction based on the bite depth and opposing position information displayed on the display section such that the relative position can be adjusted at a position that provides the desired bite depth. Thus, the relative position can be easily and stably adjusted at the position where the bite depth compliant with the desired product standards is achieved.

Note that, in the present configuration, the adjustment-value outputting means may be configured to include a correction position information calculating means to calculate a correction position information indicating the relative position in the opposing direction, which provides a desired bite depth, based on both the bite depth inputted by the bite-depth inputting means and the opposing position information when the fixed-side streaks and moving-side streaks are formed in the test piece. The adjustment-value outputting means may also be configured to execute a control content for displaying the thus-calculated correction position information on the display section.

According to this configuration, by operating the opposing-position adjusting means in accordance with the correction position information, the position adjustment can be performed more easily and stably for providing the desired bite depth.

In the rolling apparatus described above according to the present invention, a configuration is proposed in which the adjustment-value outputting means is configured to display a movement-amount corresponding graphic part on a predetermined display section, and in which the correction-movement-amount calculation controlling means is configured to execute a control content for producing the movement-amount corresponding graphic part in accordance with the movement amount in directions each orthogonal to the rolling direction of the moving flat die and the opposing direction in which the fixed-side rolling-surface section is opposed to the moving-side rolling-surface section, and a control content for causing the adjustment-value outputting means to display the produced movement-amount corresponding graphic part.

The movement-amount corresponding graphic part is displayed, for example, as a bar-shaped graphic extending to the right and left with the center as an appropriate position. How far the current position of the moving flat die is deviated from the appropriate position is suggested in the graphic, and an example of a mode is shown in which the graphic indicating the current position is adapted to coincide with the graphic indicating the appropriate position, by moving the moving flat die. This allows an operator to work extremely easily based on the visual information. Note that the movement-amount corresponding graphic part may take various forms.

The rolling apparatus of the present invention has the excellent effect of being able to easily correct the relative positions of the fixed flat die thereof and the moving flat die thereof.

Embodiments of the present invention will be described with reference to examples. Note that the present invention is not limited to the examples described below, and the designs in the examples can be modified as appropriate.

As shown in, a rolling apparatusincludes a base table. On the base table, there are disposed both a fixed flat diehaving a fixed-side rolling-surface sectionand a moving flat diehaving a moving-side rolling-surface section. The moving flat dieis caused to go and return along the rolling direction. The moving flat dieis halted at a standby position before starting rolling while the rolling apparatusis not in operation. The standby position is away from the fixed flat diein the rolling direction, as specifically shown in, and is different from a rolling start position (top dead center) to be described later.

In the description of the embodiment, the direction orthogonal to the rolling direction and in which the fixed-side rolling-surface sectionfaces the moving-side rolling-surface section, is referred to as the opposing direction (see).

The fixed flat dieis fixed to a die blockby a clamping means (not shown). The die blockis fastened on the base tablewith fastening boltsand, and immovably fixed to the base tabletogether with the fixed flat diewhile the fastening boltsandare being fastened.

The moving flat dieis disposed immovably in the up-and-down direction and the opposing direction while being reciprocally movable in the rolling direction through use of a guiding rail (not shown) disposed on the base tablealong the rolling direction. On the base table, a drive controller (not shown) is disposed. The drive controller controls the reciprocal movement of the moving flat die.

The moving flat dieis halted, with respect to the fixed flat die, at the standby position located at one side in the rolling direction while the rolling apparatusis not in operation as described above (), and is moved to the top dead center to be described later before starting rolling (). In the rolling processing, the moving flat dieis reciprocally moved starting from the top dead center along the rolling direction. After finishing the rolling processing, the moving flat diereturns to the standby position. Moreover, in the configuration of the embodiment, a correction boltis disposed () for adjusting the position (position along the rolling direction) of the top dead center of the moving flat die. This allows the position of the top dead center of the moving flat dieto be adjustable along the rolling direction by rotating the correction boltforward or reverse.

In addition, in one side of the fixed flat die, a guide path sectionis disposed for feeding a base materialbetween the fixed flat dieand the moving flat die. The rolling apparatusaccording to the embodiment causes the base materialfed by the guide path sectionto be compressed between the fixed-side rolling-surface sectionof the fixed flat dieand the moving-side rolling-surface sectionof the moving flat die, and causes the moving flat dieto reciprocally move in the rolling direction, thereby rolling processing the base material. The rolling apparatusaccording to the embodiment forms male threads by rolling processing base materials having a substantially round bar shape.

In this embodiment, since known configurations are applicable to the configuration (the guiding rail, drive controller, etc.) for causing the moving flat dieto reciprocally move, the fixed-side rolling-surface section, and the moving-side rolling-surface section, the details thereof will be omitted.

Next, a principal part of the present invention will be described.

In the embodiment, as shown in, the base tableincludes a block-position reference sectionto which the die blockis attached movably in the opposing direction. Then the die blockis movable in the opposing direction with respect to the block-position reference section(base table) in the state of the fastening bolts,being loosened. Thus, the die blockcan be slid in the opposing direction while being in this state. With this configuration, the fixed flat dieand the die blockcan be integrally moved in the opposing direction while the fixed flat dieis being fixed to the die block.

In the block-position reference section, position converting pull-out bolts,are disposed at respective portions close to both ends of the block-position reference sectionin the rolling direction. Further, at each portion closer to the respective ends than the respective position converting pull-out bolts, position converting push bolts,are disposed with being aligned up and down. The position converting pull-out boltsand position converting push boltsare disposed, with each being oriented along the opposing direction.

The position converting pull-out boltsare rotatably attached to the block-position reference section, and the tip portions thereof protrude through the block-position reference sectiontoward the die blockside so as to be screwed into the die block. Rotating the position converting pull-out boltsin one direction (e.g., to the left) causes the die blockto move away from the moving flat diein the opposing direction. Each of the position converting pull-out boltsis individually rotatable by operation. By individually operating the rotation of the individual position converting pull-out bolts, each of the positions close to both ends of the die block(fixed flat die) in the rolling direction can be individually converted so as to be away from the moving flat diein the opposing direction.

The position converting push boltsare rotatably attached to the block-position reference section, and the tip portions thereof protrude through the block-position reference sectiontoward the die blockside so as to abut against the die block. Rotating the position converting push boltsin one direction (e.g., to the right) causes the die blockto be moved by pressing in the opposing direction approaching the moving flat die. Each of the position converting push boltsis individually rotatable by operation. By individually operating the rotation of the individual position converting push bolts, each of the positions close to both ends of the die block(fixed flat die) in the rolling direction can be individually converted so as to approach the moving flat diein the opposing direction.

Note that, a commonly used mechanism can be applied to the mechanism for adjusting the position of the die block(fixed flat die) in the opposing direction by appropriately operating the rotation of the two position converting pull-out boltsand the four position converting push bolts. Thus, details thereof will be omitted.

Further, the block-position reference sectionis provided with opposing-position detecting sensors,to detect where the opposing position of the die block(fixed flat die) locates (hereinafter, referred to as an opposing-directional position) at respective portions close to both ends of the block-position reference sectionin the rolling direction (see). The opposing-position detecting sensors,detect the respective portions close to both ends of the fixed flat diein the rolling direction. This configuration makes possible the detection of the opposing position of each of the portions close to both ends of the fixed flat die.

Moreover, in the embodiment, the fixed flat dieis disposed slidably in the rolling direction with respect to the block-position reference sectionwhile the fastening bolts,are being loosened. Then the block-position reference sectionincludes an adjustment bolt (not shown) for subjecting the fixed flat dieto a position conversion in the rolling direction. By rotating the adjustment bolt by operation, the fixed flat diecan be slid in the rolling direction. Then the block-position reference sectionis provided with a rolling-position detecting sensor(see) for detecting the position (hereinafter, referred to as the rolling-directional position) of fixed flat diein the rolling direction.

In this way, the fixed flat dieaccording to the embodiment can be subjected to a position conversion in the opposing direction by rotating both the position converting pull-out boltsand the position converting push boltsby operation, and a positional conversion in the rolling direction by rotating the adjustment bolt by operation, while the fastening bolts,are being loosened. Then the fastening bolts,are fastened to position and fix the fixed flat die.

The rolling apparatusaccording to the embodiment includes a position detecting devicethat includes the opposing-position detecting sensors,and the rolling-position detecting sensor, as shown in. The position detecting deviceincludes a control PCand a touch panel. The control PCreceives both signals detected by the opposing-position detecting sensors,and signals detected by the rolling-position detecting sensor. The control PC includes a central controller and a storage device, and controls the display of the touch panel.

The position detecting devicefurther includes a top-dead-center detecting sensorfor detecting the position of the top dead center of the moving flat die. Signals detected by the top-dead-center detecting sensorare fed into the control PC. Here, the top-dead-center detecting sensoris intended to detect the top dead center (the starting position of rolling processing), from which the rolling processing is started, of the moving flat die, and is disposed in the base table.

The storage device of the control PCstores, in advance, product standard information (information on a nominal diameter, a pitch, etc.) regarding threads to be rolling-processed, and various programs or the like with which conditions and the like of the rolling processing are calculated based on the standard information. Specific programs stored in the storage device include a program for calculating a movement amount of reciprocal movement of the moving flat die, a program for calculating a correction movement amount that is used to correct the position of the top dead center of the moving flat die, and a program for calculating correction position information regarding the opposing-directional position of the fixed flat die.

Here, the program for calculating a movement amount of reciprocal movement of the moving flat die, calculates the movement amount of reciprocal movement based on outer diameter data of the product standard information described above. Moreover, the program for calculating a correction movement amount of the top dead center, calculates the correction movement amount based on information regarding the nominal diameter, the pitch, etc. according to the product standard information described above, and inputted information inputted by an operator. The inputted information is information inputted through use of the touch panelas described later, is data obtained from actual measurements of a test pieceto be described later, and includes information regarding such as a thread direction, the level of the moving flat die, and a positional deviation amount P. Through the program, the correction movement amount is calculated using the nominal diameter and pitch according to the product standard information, the positional deviation amount P inputted by an operator as described later, the information inputted by the operator regarding the level of the moving flat die, and pi, the ratio of the circumference of a circle to its diameter. According to the thus-calculated correction movement amount, the correction boltis operated to adjust the moving flat dieto be positioned at a proper top dead center.

Moreover, through the program for calculating the correction position information regarding the opposing-directional position of the fixed flat die, the correction position information is calculated based on the nominal diameter and pitch according to the product standard information described above, data from the actual measurements of the test piece, and the like. Specifically, the correction position information corresponding to each of the positions detected by the opposing-position detecting sensors,described above, is calculated using the information, including a bite depth T inputted by an operator as described later, the nominal diameter and pitch according to the product standard information, and the information regarding the opposing-directional position detected by the opposing-position detecting sensors,described above. In accordance with the correction position information for each of these detected positions, the position converting pull-out boltsand position converting push boltsare operated to adjust the fixed flat dieto be set at a position where the rolling can be performed with an appropriate bite depth.

Under the display control by the control PC, the touch paneldisplays by switching the correction movement amount of the top dead center of the moving flat dieshown inand the correction position information regarding the opposing-directional position of the fixed flat dieshown in. Such a display-switching can be carried out by operation by an operator. Note that, since the operation, processing, etc. of the switching can be applied with conventionally known means, the details thereof will be omitted.

In the case where the correction movement amount of the top dead center of the moving flat diedescribed above is displayed, as shown in, the following parts are displayed on the screen of the touch panel. That is, a standard displaying partthat selectively displays thread standards (nominal diameter, pitch, thread direction, etc.), a level displaying partthat displays the inputted information regarding the level of the moving flat die, a positional-deviation-amount displaying partthat displays the inputted positional deviation amount P, and a bar-shaped correction graphic part. The touch panelis the same as that commonly used, and can be operated by an operator by touching predetermined portions thereof. Specifically, upon touching on the standard displaying partby the operator, one of a plurality of pieces of preset product standard information is selected and displayed. In the correction graphic part, at a center portion thereof in the longitudinal direction, there are displayed both a vertical line-shaped target-position displaying partand a vertical line-shaped current-position displaying partcorresponding to the correction movement amount. The distance, how far the display position of the current-position displaying partis separated from the target-position displaying part, indicates the correction movement amount. As the correction movement amount becomes smaller, the display position of the current-position displaying partapproaches the target-position displaying part. Then, when the correction movement amount=0 (zero), the current-position displaying partcoincides with and is displayed together with the target-position displaying part. In addition, the touch paneldisplays a rotational-direction indication displaying partthat indicates the rotary direction of the correction boltdescribed above, and a target-value achievement displaying partthat indicates that the current-position displaying partcoincides with the target-position displaying part.

On the other hand, when displaying the correction position information regarding the opposing-directional position of the fixed flat die, as shown in, the following parts are displayed on the screen of the touch panel. That is, the standard displaying partdescribed above; a bite-amount displaying partthat displays the inputted bite depth T; first to third current-position displaying partstothat display the current position information regarding the fixed flat diedetected by the opposing-position detecting sensors,and the rolling-position detecting sensor; and first to third correction-position information displaying partstothat display the correction position information regarding the fixed flat die corresponding to the respective detected positions detected by these detecting sensorsand.

Next, a description will be made regarding a correction method for performing, before rolling processing, position adjustment to both the top dead center of the moving flat dieand the opposing-directional position of the fixed flat die, in accordance with the product standards (the nominal diameter of the thread). Here, the correction method is performed using a test pieceproduced by rolling processing a base material.

First, the test pieceis produced. The production of the test pieceis performed under an instruction to produce the test piecevia the touch panel(not shown). In the embodiment, the drive controller disposed in the base tabledescribed above, performs control steps for producing the test piece in accordance with the operation via the touch panel. This drive controller corresponds to the test-movement control means according to the present invention.

More specifically, the product standards (the nominal diameter, pitch, and thread direction) of the thread product to be produced are selectively inputted via the touch panel, thereby giving instruction to start steps of producing the test piece.

The test pieceis produced as follows: The moving flat dieis caused to move in the normal direction of the rolling, from the state where, as shown in, the base materialis sandwiched between the fixed-side rolling-surface sectionof the fixed flat dieand the moving-side rolling-surface sectionof the moving flat dieat the top dead center, until the state where, as shown in, the base materialis rotated a half-turn. By this processing, there are formed, in the base material, both groove-like fixed-side streaksbased on the fixed-side rolling-surface sectionand moving-side streaksbased on the moving-side rolling-surface section(seeand).

Note that how the moving flat dieis caused to move until the base materialis rotated a half turn is as follows: Since the nominal diameter, thread pitch, etc. of the thread product to be produced have been inputted in advance, the program of the position detecting deviceis executed to calculate a movement amount for the moving flat die, based on the outer circumferential length of a to-be-processed portion of the test piece. Then, the drive controller performs the control under which the moving flat dieis automatically moved to go from the top dead center, by the calculated movement amount.

After the base materialdescribed above has been rotated a half turn, the moving flat dieis automatically recovered to the top dead center (return operation). In this way, the drive controller performs the control to automatically cause the reciprocal movement of the moving flat die, which results in the formation of both the fixed-side streaksand moving-side streaksin the base material, thereby completing the test piecehaving these streaksand.

In the test piece, as shown inand, the fixed-side streaksand the moving-side streaksare formed. Here, any one of the grooves formed as the fixed-side streaksis selected. Then, in a front elevation view of the test piece, a groove center line, the center line of the selected groove formed along the longitudinal direction thereof, is determined. Then a virtual groove center line W is defined that is obtained by extending this groove center line. A moving-side groove center line V is determined for the corresponding groove formed as the moving-side streaks. Then the positional deviation amount P of the moving-side groove center line V is measured with respect to the virtual groove center line W. The positional deviation amount P is measured as a positional deviation amount of the moving-side groove center line V with respect to an appropriate position, in the direction along the axis of the test piece, the appropriate position being defined as a position where the moving-side groove center line V coincides with the virtual groove center line W. For example, the moving-side groove center line V is measured to be 0.29 mm lower (i.e., to be farther away from the top of the test piece) than the virtual groove center line W of the selected grooved.