JP3205650B2 - Chock desorption equipment in rolling mill - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for detaching a chock from a work roll taken out for a regular repair from a rolling mill or for an abnormal replacement.

[0002]

2. Description of the Related Art Work rolls of a rolling mill are taken out of a rolling mill stand regularly or abnormally due to wear, rough surfaces, etc., and after being polished and repaired, the work rolls are incorporated into the rolling mill again. The work roll taken out from the rolling mill together with the chock is carried on a roll support table, and the work roll that has been polished and repaired is replaced with a chock.

[0003] This procedure will be described in more detail.
A pair of upper and lower work rolls taken out of the rolling mill are transported one by one by a crane onto a roll support table, and are usually arranged alternately with the work rolls transported to the roll support table after the polishing process. Next, the receiving base of the chock supported by the traveling carriages on both sides of the support platform so as to be able to move up and down and to move left and right (to advance and retreat toward the support platform) is moved up and down and the traveling carriage moves.
It is positioned up and down and back and forth, then moves forward by a fixed amount toward the support table, and receives and retreats the chock that has been released from being fixed to the roll neck. After moving along the support table and parallelly moving to the repaired roll position after polishing, centering the chock and the roll while finely adjusting the chock receiver back and forth and up and down, then head to the end of the chock receiver roll To move forward and insert the chock into the roll neck and then secure it.

Conventionally, the above-mentioned fixation of the chock to the roll neck and its release have been performed manually as follows. That is, to release the fixation, after rotating the adjuster ring to loosen it, loosen the thrust clamp band attached to the outer periphery of the thrust clamp ring to release the crimp to the two-part thrust clamp ring, and then release Remove the thrust clamp ring through bolts and remove the thrust clamp ring from the roll neck.Fixing of the chocks is performed in the reverse order, but turning the adjuster ring and tightening the thrust clamp band Or, the replacement of the chocks, such as the release of the bolts and the attachment and detachment of the through bolts, required considerable labor and labor.

In order to solve this problem and to enable automatic attachment and detachment of the chock, Japanese Patent Application Laid-Open No. Hei 5-23718 shows that the chock is integrated with the chock 1 as shown in FIG.
In addition, it has an adjust ring 6 screwed into a ring carrier 5 to which a key 4 inserted into the key groove 3 of the roll neck 2 is connected, and a claw 8 fitted into the annular groove 7 of the roll neck 2 and pushes the pin 10. A thrust clamp that projects outward by the action of the coil spring 9 and that is fitted and locked in the locking groove 11 of the roll neck 2 and that is locked from rotation, and is integrally connected to the adjust ring 6. Ring 1
In addition to providing a chock fixing device consisting of 3 above, a chock receiving base is provided on the traveling vehicle, and the work roll supported by the roll receiving base is sandwiched between the axes of the work rolls, and extends on both sides thereof in parallel with the axis. A pair of clampers rotatable at a fixed angle around the axis are provided as a drive source.
Is supported on the chock cradle, the locking piece 12 is pushed by the clamper, and the thrust clamp ring 1 is pressed.
After the locking piece 12 is depressed from the locking groove 11 by pushing the locking piece 12 to be rotatable,
By rotating the thrust clamp ring 13 together with the adjust ring 6 by a predetermined angle using the clamper, the claw 8 is
In a state in which the notch groove of the roll neck 2 formed in the more axial direction is matched and the insertion / removal is possible, the traveling bogie is retracted, the chock 1 is pulled out from the roll neck 2, and the procedure reverse to that described above is performed when attaching the chock. There has been proposed a chock attaching / detaching device in which a chock is inserted into a roll neck and fixed.

[0006]

According to the above-described apparatus having a clumbar, the change of the chock can be automatically performed, and the labor and labor conventionally required for the change of the chock can be saved. However, there is still room for improvement in this device. One of them is a countermeasure for a case where the work roll is displaced in the axial direction from a predetermined position when the work roll is mounted on the roll receiving stand by a crane operation. If the work roll mounted on the roll receiving stand is displaced in the axial direction, when the traveling carriage is advanced by a certain amount, the clamber does not reach the thrust clamp ring, and even if it reaches, the locking piece is fully pushed The rotation stop cannot be released due to the inability of the thrust clamp ring or locking piece to reach the forward end of the thrust clamp ring. There is a risk of damaging the crumbers supported by the stopper.

[0007] A first object of the present invention is to solve the above-mentioned problem, and even if the work roll mounted on the roll receiving table is slightly displaced in the axial direction from a predetermined position, the clamper pushes the locking piece by a fixed amount. In this way, the rotation stop can be reliably released, and the thrust clamp ring or the locking piece can be reliably locked. A second object of the present invention is to solve the problem that a work roll mounted on a roll receiving stand is displaced in an axial direction from a predetermined position.

A third object of the present invention is to provide a detecting means for detecting the engagement of the clamper with the thrust clamp ring or the engaging piece so that it can be confirmed whether or not the engagement has been performed. The object of the invention is to detect whether or not the locking piece has been pushed in by a fixed amount and the rotation stop has been reliably released. A fifth object of the present invention is to
In order to be able to handle work rolls with different diameters,
It is intended to make it possible to expand and contract the interval between the clumpers.

[0009]

To achieve the first object, a chock attaching / detaching device is provided with a roll cradle for supporting a work roll, and a traveling trolley capable of moving back and forth in the axial direction of the work roll supported by the roll cradle. A first actuating device for retreating the traveling vehicle by a fixed amount, and a chock receiving base for supporting the chocks and a work roll supported on the roll receiving platform, which are mounted on the traveling vehicle, and a shaft is provided on both sides thereof. A thrust clamp ring provided with a pair of clambers extending parallel to the center and rotatable by a fixed amount around the axis, and a pawl in which a chock fixing device is slidably fitted into an annular groove of the roll neck; A locking piece that is rotatably supported in the axial direction by the thrust clamp ring and that is fitted and locked in a locking groove formed in the roll neck to stop the rotation of the thrust clamp ring; Stop groove A spring for urging so as to fit, provided on the thrust clamp ring or lock piece,
In a device for detaching a chock in a rolling mill having a locking means for engaging and disengaging the tip of the crumb bar, a second mechanism for moving the crumb bar forward and backward in the work roll axis direction.
And a stopping means for stopping the operating device when the load of the second operating device reaches a set value.

According to the present device, when the chock is detached, the traveling vehicle first moves forward by a predetermined amount by the first operation operation.
The crumb is advanced by the second actuator. As a result of this advance, the clamber hits the locking piece, pushes the locking piece by a certain amount, and engages with the locking means. If the forward movement is continued while the forward movement of the crumb bar is prevented by the engagement, the load of the second operating device increases, and when the load exceeds a certain amount, the second operating device stops. Is done.

As described above, in the present apparatus, the clamper pushes the locking piece by a predetermined amount by the second operating device, and moves forward until it engages with the locking means. As the locking means used in the present apparatus, for example, a protrusion protruding from the thrust clamp ring adjacent to the locking piece, formed into a projection that is fitted and locked to the bifurcated end of the crumb bar, a locking piece, For example, a concave portion whose leading end is fitted and locked is exemplified. Of these, a recess formed in the locking piece is desirable. The crumb bar only needs to have a shape that allows the tip to fit into the recess.The structure is simple.In addition, the fitting of the locking piece and the rotation of the thrust clamp ring can be performed simply by fitting the tip of the crumb bar to the projection. This is because locking can be performed.

In the case where a hydraulic cylinder is used as the actuating device, for example, the pressure of the hydraulic circuit is detected, and when the pressure reaches the set pressure, the motor driving circuit is opened to stop the motor. Or a pressure switch for stopping the oil supply to the hydraulic cylinder by switching the switching valve, a pressure sensor for detecting the pressure of the hydraulic circuit, and stopping the operating device when the pressure detected by the pressure sensor reaches the set pressure. For example, when a motor is used, a detector that detects the torque of the motor, and a torque detected by the detector may be used as a set pressure. When reached, a control device can be used that opens a control switch that controls the motor drive circuit.

According to a second aspect of the present invention, there is provided a chock attachment / detachment device which allows a chock receiving base of the above apparatus to be movable, moves the chock receiving base back and forth by a third operating device, and supports the work roll supported by the roll receiving base. In the axial direction. According to this device, when the work roll mounted on the roll cradle is shifted to one of the work side and the drive side on a business trip, the third actuating devices on both sides push the chock cradle together. The displacement is eliminated by pushing.

[0014] The third workside and driveside actuators are usually adapted to push the chock cradle simultaneously and by the same amount, so that when the load is balanced or after the load has reached the set value. At this time, both operating devices are stopped at the same time. The load on the actuator on the business trip side is initially larger than the load on the retracted side because the work roll is pushed and moved, but when the work roll shift is resolved, the load on both actuators is reduced. When the load is further increased and reaches the set value after or after the equilibrium, both actuators are simultaneously stopped.

An apparatus for detaching a chock is disclosed in JP-A-5-2371.
As shown in No. 8, the work rolls can be mounted on the roll cradle in two upper and lower stages, and the chock cradle and the crumb bar are provided on the upper and lower sides. It is desirable to be able to detach simultaneously. In this case, the upper and lower chock receivers can be simultaneously moved forward and backward by the fourth operating device, and the upper and lower clumbers can be simultaneously moved forward and backward by the fifth operating device. , And the clambers can be individually moved back and forth by a second actuator.

According to a third aspect of the present invention, there is provided a chock attaching / detaching device, comprising: a roll receiving base for supporting a work roll; a traveling vehicle capable of moving back and forth in the axial direction of the work roll supported by the roll receiving base; And a first actuating device for retracting the work roll by a fixed amount, and a work roll installed on the traveling carriage and supporting the chocks, and a work roll supported by the roll support, sandwiching the axes of the work rolls on both sides thereof in parallel with the axis. A thrust clamp ring having a pair of claws that extend and are rotatable around the axis by a fixed amount, and are provided with claws that allow the chock fixing device to slidably fit into the annular groove of the roll neck;
A locking piece rotatably supported in the axial direction by the thrust clamp ring and fitted to and locked in a locking groove formed in the roll neck to stop the rotation of the thrust clamp ring; And a locking means provided on a thrust clamp ring or a locking piece for locking and engaging the tip of the crumb bar so as to be removably fitted. A detection rod, which is attached to at least one of the pair of clambers so as to be able to advance and retreat, and when a relative movement amount between the detection rod and the clamber reaches a set value, detects it and outputs it to the control device. And a sensor that performs the measurement.

In this device, when the locking means is a concave portion, after the detection rod hits the peripheral edge of the concave portion and stops, the clamber continues to advance further and engages with the concave portion, but the detection rod stops. When the movement amount of the later cram bar reaches the set value and the sensor detects this, the fitting and locking of the crum bar into the concave portion is confirmed. In the case where the locking means is a convex, the detection rod is brought into contact with the convex, and after hitting the convex and stopping, the clamp bar continues to advance further and the fork at the tip engages and locks the convex. Become like Therefore, in this case, when the moving amount of the crumbar after the detection rod hits the projection and stops is reached to the set value, the fitting and locking of the cranber to the projection is confirmed.

A fourth aspect of the present invention is directed to a chock attaching / detaching device, wherein the detecting rod of the above device contacts a thrust clamp ring, and the clamp bar contacts an engaging piece. . According to this device,
After the detection rod hits the thrust clamp ring and stops, the cram bar continues to advance and pushes in the locking piece, or the locking piece is pushed in until it comes out of the locking groove, and the amount of movement of the clamber after the detection rod stops moving. Reaches the set value,
When this is detected by the sensor, detachment of the locking piece from the locking groove is confirmed.

Preferred examples of the sensor used in the present apparatus include a limit switch that operates in contact with the rear end of the detection rod, a proximity switch that detects the rear end of the detection rod, and the like. A chock attaching / detaching device for achieving a fifth object includes a roll receiving base for supporting a work roll, a traveling carriage that can advance and retreat in the axial direction of the work roll supported on the roll receiving base, and a fixed amount of the traveling carriage. A first actuating device to be retracted, and a work roll supported on a chock supporter and a roll supporter, which is installed on a traveling trolley, and extends on both sides thereof in parallel with the axis, A thrust clamp ring provided with a pair of clamp bars rotatable by a fixed amount around the axis, a claw fixing device having claws slidably fitted in the annular groove of the roll neck, and a thrust clamp ring having a shaft. A locking piece which is rotatably supported in the direction and is fitted and locked in a locking groove formed in the roll neck to stop rotation of the thrust clamp ring, and the locking piece is fitted in the locking groove. Energize A pinion rotatably driven by a pulse motor in a chock attaching / detaching device in a rolling mill having a spring and a locking means provided on a thrust clamp ring or a locking piece, the locking means being adapted to removably fit and lock the tip of the cramber. And, it consists of a pair of racks that are slidably supported in only one direction and mesh with the pinion from both sides, and connect the crumbs to the rack,
It is characterized in that it is moved integrally with the rack.

According to the present apparatus, when the pinion is rotated, the racks move parallel to each other in opposite directions, thereby increasing or decreasing the interval between the clambers.

[0021]

FIG. 2 shows a chock detaching apparatus according to the present invention.
Can be mounted at regular intervals in the upper and lower stages, and on both sides thereof, a traveling carriage 23 is supported on a rail 24 so as to be movable along the axial direction of the work roll 22,
Each can be advanced and retracted toward the work roll 22 by a hydraulic cylinder 25 as a first operating device.

The traveling carriage 23 has a movable platform (not shown) which advances and retreats toward a work roll by the operation of a hydraulic cylinder as a fourth operating device (not shown), and a support frame 26 attached to the movable platform. A mounting table 28 which is mounted on the moving table and supported so as to be able to move up and down, and whose vertical position is adjusted by a wedge 27 which moves forward and backward by the operation of a hydraulic cylinder 60 attached to the moving table; and a hydraulic cylinder 4 as a fifth operating device
4, a moving table 37 that moves forward and backward toward the work roll, and a high and low supporting table 29 provided on the moving table 37;
30 is provided, and a chock receiving base 31 for supporting the chock is supported on the mounting base 28 in two upper and lower stages at fixed intervals, each of which is movable toward the work roll 22,
It can be advanced and retracted by a hydraulic cylinder 59 as a third operating device.

The work side and drive side hydraulic cylinders 59 have the same hydraulic circuit so that both operate simultaneously and move the chock cradle 31 forward and backward by the same amount. The circuit is provided with a pressure switch, and when the pressures of the two hydraulic circuits are respectively increased and balanced, and then further increased to reach a set pressure, the pressure switch operates to switch the switching valve, and the hydraulic cylinder 59 Oiling is stopped.

Each of the support bases 29 and 30 has a pair of clamp bars 33 which extend parallel to both sides of the axis of the work roll 22 at the upper ends thereof and which can rotate at a fixed angle around the axis. I have. FIG. 3 and FIG.
3 and details of the support bases 29, 30. Each of the support bases 29, 30 has an inverted U-shaped cross section, and one of the support bases 29 is supported by a pair of supports 35 on the traveling carriage 23. A support frame 30 is movably mounted on a rail 38 laid in parallel on a plate-like movable table 37 movably mounted on a parallel rail 36, and a gate-shaped frame attached to the movable table 37. 39 is movably mounted on a rail 41 laid on the upper end. And each support base 29, 30
The movable cylinder 37 and the hydraulic cylinder 42 as a second operating device attached to the frame 39 are configured to be able to advance and retreat, respectively, of which the upper hydraulic cylinder 42 is an upper chock cradle supported by the mounting table 28. And a lower hydraulic cylinder 4
Reference numeral 2 denotes a hydraulic circuit (not shown) configured to operate in synchronization with a hydraulic cylinder 59 for moving the lower chock receiving base 31 forward and backward.
A pressure switch is provided, and when the oil pressure reaches a set pressure, the pressure switch is operated to switch the switching valve, so that oil supply to the hydraulic cylinder 42 is stopped.

On the other hand, the moving table 37 is also mounted on a shelf 43 fixed to the column 35, and can be advanced and retracted by a hydraulic cylinder 44 as a fifth operating device which operates in synchronization with the fourth operating device. is there. An elongated box-shaped rotator 46 is provided at the upper end of each of the support bases 29 and 30 so that the center thereof is rotatable by a bearing 47 so that the center of the work body 22 is extended along the axis of the work roll 22 mounted on the roll receiving base 21. It is supported and can be rotated at a fixed angle by a gear motor 48 mounted on a support base.

The rotating body 46 has guide grooves 50 on the left and right sides of the front surface.
Are formed symmetrically and have a pinion 52 internally rotatably driven by a gear motor 51 inside.
Are supported so as to be vertically movable in a direction orthogonal to the axis, and a pair of racks 53 meshing with the pinion 52 from above and below, and a piece 54 fixed to each rack 53
Each piece 54 is symmetrical with respect to the axis, and extends along the axis through the guide groove 50.
And a detection rod 56 slidably attached to the clamber 33.
As shown in detail in FIG. 5, the detection rod 56 is urged by a spring 57 so as to always protrude,
When the tip is located at a position slightly retracted from the tip of the cranber, the detection rod 56 is retracted by a certain amount or more against the action of the spring 57, and when the proximity switch 58 detects it, a detection signal is output to a control device (not shown). Accordingly, the control device transmits a control signal in accordance with the installed program, and turns on a control switch in the control circuit of the geared motor 48 to drive the geared motor 48 by a fixed amount.

The present apparatus is configured as described above, and the chocks are removed from the work roll 22 mounted on the roll receiving table 21 as follows. First, data on the type of the work roll 22 is input to the control device,
The control device rotates the geared motor 51 by a predetermined amount based on the rotation of the geared motor 51, and moves the clamber 33 in the radial direction in accordance with the size of the work roll 22, thereby expanding or contracting the interval between the two clambers.

Next, the work roll 22 is placed on the roll receiving stand 21.
The work carriage 23 on both the work side and the drive side is mounted on the hydraulic cylinder 2 with the
The operation is advanced by a certain amount by the operation of step 5. After the traveling vehicle 23 has advanced by a predetermined amount, the hydraulic cylinder 44 and a hydraulic cylinder (not shown) as a fourth operating device are operated to further advance the mounting platform and mobile platform 37 (not shown) by a predetermined amount, Then the hydraulic cylinder 5 of the chock cradle
9 and the hydraulic cylinder 42 are operated to move the chock cradle 31 and the cranber 33 forward.

When the chock cradle advances, the chock is first received, and then, when the work roll is shifted to one of the work side and the drive side, the work roll is pushed in from the side where the business roll was made. The other chock cradle receives chock only, and does not push the work roll. When the work roll is pushed in from one side and the displacement is eliminated, the work roll is pushed in by the operation of the hydraulic cylinder on the other side, and the hydraulic pressures of the hydraulic cylinders 59 on both sides for pushing the work roll are balanced. Leads to. In this state, if the user still tries to push in, the hydraulic pressures of both hydraulic cylinders 59 increase. When the hydraulic pressures reach the set pressure, a pressure switch (not shown) is operated, and the switching valve is switched to send the hydraulic pressure to both hydraulic cylinders 59. Oil is stopped.

On the other hand, during the forward movement of the clamp bars 33, each of the clamp bars 33 is engaged with the locking piece 12 shown in FIG.
To fit into the concave portion 14 formed in the locking piece 12.
After the detection rod 56 hits the thrust clamp ring 13, when the clamp bar 33 further advances, the locking piece 12 is pushed in and comes out of the locking groove 11. After the locking piece 12 has been pushed in until its movement is prevented by the thrust clamp ring 13, if the locking piece 12 is still to be pushed in, the oil supply pressure to the hydraulic cylinder 42 increases. Then, when the pressure rises to the set pressure, the pressure switch is operated to switch the switching valve, the oil supply to the hydraulic cylinder 42 is stopped, and the cranber 33 is stopped.

The locking piece 12 is a thrust clamp ring 13
When the switch is pushed until the movement is stopped, the proximity switch 58 detects the rear end of the detection rod. When the proximity switch 58 detects the rear end of the detection rod, the gear motor 48 is driven by a control signal transmitted from the control device based on the detection signal, and the rotating body 46 is rotated by a predetermined angle. This allows the thrust clamp ring 1
3 rotates a fixed amount, and the claw 8 matches the notch groove. Thereafter, the traveling carriage 23 is retracted by a certain amount by the operation of the hydraulic cylinder 25, and the chock 1 comes off the roll neck 2.

Attachment of the chock to the work roll is performed by following the reverse procedure.

[0033]

The present invention is configured as described above and has the following effects. According to the attaching / detaching device according to the first aspect, even if the work roll mounted on the roll receiving table is slightly displaced in the axial direction from the predetermined position by the crane operation, it is ensured that the locking piece is disengaged from the locking groove by the crumb bar. It can be pushed in, and the clamber can be fitted and locked to the locking means.

According to the second embodiment, the chock can be supported at a predetermined position on the chock receiving table. According to the attachment / detachment device of the third aspect, the attachment / detachment of the chock can be simultaneously performed on the pair of work rolls supported vertically. In the detaching device according to the fourth aspect, it is possible to detect whether or not the clamp bar has been fitted and locked to the locking means. In the detaching device according to the fifth aspect, the locking piece is pushed in to lock the locking groove. It can be detected whether or not the user has left.

According to the detaching device of the sixth aspect, it is possible to change the interval between the crumbers, and to cope with various work rolls having different diameters. If the locking means is formed as a recess and the clamp is fitted and locked in the recess as in the device according to claim 7, the structure of the clamp is simplified, and the pushing of the locking piece and the rotation at the time of rotation are performed with the clamp. Locking can be performed.

[Brief description of the drawings]

FIG. 1 is a sectional view of a main part of a chock.

FIG. 2 is a schematic diagram of a chock detachment device according to the present invention.

FIG. 3 is a front view of a main part of the chock detaching device according to the present invention.

FIG. 4 is a side view of the detachable device shown in FIG. 3;

FIG. 5 is an enlarged front view of a cranber provided with a detection rod.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Chock 2 ... Roll neck 6 ... Adjust ring 8 ... Claw 9 ... Coil spring 11 ... Lock groove 12 ... Lock piece 13 ... Thrust clamp ring 14. ··· Recess 21 ··· Roll receiving stand 22 ··· Work roll 23 ··· Traveling carriage 25, 42, 44, 59, 60 ··· Hydraulic cylinder 29, 30 ··· Support base 31 ··· Chock receiver Table 33 ... Clamber 46 ... Rotating body 48,51 ... Gard motor 52 ... Pinion 53 ... Rack 56 ... Detection rod 58 ... Proximity switch

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Hiroaki Hayakawa 20 Nakagami, Toinmachi, Inaba-gun, Mie Prefecture (72) Inventor Hiroshi Tsuji 301, Higashisakada, Habikino-shi, Osaka (72) Inventor Tsutomu Mizutani 773, Haruyo-cho, Kuwana-shi, Mie Prefecture -7 (56) References JP-A-5-23718 (JP, A) JP-A-52-110255 (JP, A) JP-A-4-118206 (JP, U) JP-A-52-129738 (JP, U) (63) Field surveyed (Int. Cl. ⁷ , DB name) B21B 31/10 B21B 31/08

Claims (7)

(57) [Claims] 1. A roll receiving platform for supporting a work roll, a traveling vehicle capable of moving back and forth in the axial direction of the work roll, a first operating device for retreating the traveling vehicle by a fixed amount, and a choke mounted on the traveling vehicle. A pair of clamps that extend parallel to the axis and are rotatable around the axis by a fixed amount on both sides of the axis of the work support and the axis of the work roll. A thrust clamp ring having a claw that slidably fits in the annular groove of the roll neck, and a shaft supported rotatably in the axial direction by the thrust clamp ring to engage with a locking groove formed in the roll neck. A locking piece that stops and stops rotation of the thrust clamp ring, a spring that urges the locking piece to fit into the locking groove, and a thrust clamp ring or locking piece provided with In a chock attaching / detaching device for a rolling mill having a locking means for removably fitting and locking, a second actuating device for moving a cranver forward and backward in a work roll axial direction, and a load of the second actuating device are set to a predetermined value. And a stopping means for stopping the operating device when the pressure reaches a predetermined value. 2. The chock attachment / detachment apparatus according to claim 1, wherein the chock cradle is movable and is pushed and moved by a third actuating device to eliminate the axial displacement of the work roll. 3. The roll receiver is configured such that the work roll can be supported up and down, while the chock receiver and the crumb bar are vertically disposed, and the chock receiver and the crumb bar are respectively a fourth and a fifth operating device. And the second and third actuators are provided in pairs, respectively, so that the chock cradle and the crumb bar can be individually moved forward and backward. Chock detachment device as described. 4. A roll receiving platform for supporting a work roll, a traveling vehicle capable of moving back and forth in the axial direction of the work roll, a first operating device for retreating the traveling vehicle by a predetermined amount, and a chock mounted on the traveling vehicle. A pair of clamps that extend parallel to the axis and are rotatable around the axis by a fixed amount on both sides of the axis of the work support and the axis of the work roll. A thrust clamp ring having a claw that slidably fits in the annular groove of the roll neck, and a shaft supported rotatably in the axial direction by the thrust clamp ring to engage with a locking groove formed in the roll neck. A locking piece that stops and stops rotation of the thrust clamp ring, a spring that urges the locking piece to fit into the locking groove, and a thrust clamp ring or locking piece provided with In a chock attaching / detaching device in a rolling mill having a locking means for engaging and disengaging and locking, a detection rod, which is attached to at least one of the pair of clambers so as to be able to advance and retreat, and a detection rod and a clamp bar. Characterized in that it comprises a sensor for detecting when a relative movement amount of the motor reaches a set value and outputting it to a control device. 5. The chock attaching / detaching apparatus according to claim 4, wherein the detection rod in the apparatus contacts a thrust clamp ring, and the clamp bar contacts the locking piece. 6. A roll receiving platform for supporting a work roll, a traveling vehicle capable of moving back and forth in the axial direction of the work roll, a first operating device for retreating the traveling vehicle by a predetermined amount, and a choke mounted on the traveling vehicle. A pair of clambers extending parallel to the axis on both sides thereof with the chock receiving base for supporting the work roll and the axis of the work roll interposed therebetween and being rotatable by a predetermined amount around the axis; A thrust clamp ring having a claw that slidably fits in the annular groove of the roll neck, and a shaft supported rotatably in the axial direction by the thrust clamp ring to engage with a locking groove formed in the roll neck. A locking piece that stops and stops rotation of the thrust clamp ring, a spring that urges the locking piece to fit into the locking groove, and a thrust clamp ring or the locking piece provided with In a chock attaching / detaching device in a rolling mill having a locking means for removably fitting and locking, a pinion rotationally driven by a pulse motor is supported so as to be slidable in only one direction, and meshes with the pinion from both sides. And a claw bar connected to the rack and moved integrally with the rack. 7. The chock attaching / detaching device according to claim 1, wherein the locking means is a recess formed in the locking piece.