JPH0633145A - High-frequency hardening method and device for crank shaft - Google Patents

Abstract

PURPOSE:To shorten the tact time of a hardening stage at the time of hardening many crank shafts. CONSTITUTION:The unhardened crank shaft W existing in a hardening standby position 3A is moved to a hardening position 3B through a first path EP and the hardened crank shaft existing in the hardening position 3B is moved through a second path into the hardening standby position 3A. The unhardened crank shaft W is hardened in the hardening position 3B. The hardened crank shaft W moved to the hardening standby position 3A is ejected during the hardening and the unhardened crank shaft W is moved from an idling station 2 in the front stage of the hardening standby position 3A to the hardening standby position 3A.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for induction hardening of crankshafts, and more particularly to induction hardening capable of shortening the takt time of the hardening process when hardening a large number of crankshafts. A method and apparatus.

[0002]

2. Description of the Related Art A conventional technique will be described below with reference to the drawings. FIG. 10 is a front view of an example of a crankshaft of a four-cylinder engine. The crankshaft W has five journals J1 to J5 and four pins P1 to P4. V is the axis of rotation of the crankshaft W and is a straight line connecting the centers of the journals J1 to J5. The crankshaft W normally quenches all the pins P1 to P4 at the same time in one station and then simultaneously quenches all the journals J1 to J5 in the other stations.
~ The case of quenching P4 will be described.

FIG. 11 shows a structure in which a large number of horizontally arranged crankshafts W are moved in the direction perpendicular to the axis V thereof and the pins P1 to P1.
FIG. 1 is a front explanatory view of an induction hardening apparatus for hardening P4, which includes a carrying-in station 1, an idling station 2, a pin hardening waiting position 3A, and a pin hardening station 3 including a pin hardening position 3B; It is equipped with an aftercooling station 4. Each of the stations 1 and 2, the quenching standby position 3A, and the station 4 is provided with a pair of V-shaped fixed blocks 11 to 14, respectively.

Between the pair of fixed blocks, a pair of parallel moving beams 20 are horizontally arranged. A plurality of struts are attached to each of these moving beams 20, and V is attached to the upper ends of these struts.
The mold moving blocks 21 to 24 are provided at equal intervals. When the moving beam 20 is in the initial state, the moving block 21
~ 24 are stations 1 and 2, quenching standby position 3A,
And at station 4 slightly lower than the fixed blocks 11-14. Reference numeral 28 is a moving beam elevating device for raising the moving beam 20 in the direction of arrow A and lowering it in the direction of arrow C. Reference numeral 29 is for moving the moving beam 20 forward in the direction of arrow B and backward in the direction of arrow D. It is a moving beam forward and backward device. With these devices, the moving beam 20 can move the arrow A,
One cycle is completed by sequentially moving in the directions of B, C and D.

The crankshaft W placed on the pair of fixed blocks 11 is placed on the fixed block 13 at the quenching standby position 3A by the movement of the moving beam 20 in two cycles, and then the pair of arms 38, Both ends are supported by a pair of centers (not shown) provided near the tips of the arms 38, and then one end is gripped by a chuck (not shown) provided near the tips of the one arm 38. Then, after this, the crankshaft W is carried to the quenching position 3B by rising in the direction of the arrow P about the shaft 39 of the arms 38, 38.

Then, a high-frequency heating coil (hereinafter referred to as a high-frequency heating coil) 30 provided for each of the pins P1 to P4 30 descends in the direction of arrow R and the pins P1 to P4
Placed on P4. The crankshaft W is rotated by a crankshaft rotating device (not shown) provided on the arm 38, and a high frequency current is applied to the heating coils 30 for a predetermined time, and then a pair of jackets 3 provided at both ends of each heating coil 30.
Cooling liquid is sprayed from the pins 1 and 31 to the heated pins P1 to P4, respectively, to complete the quenching of the pins P1 to P4.

After that, the heating coil 30 rises in the direction opposite to the arrow R, and the arms 38, 38 descend about the shaft 39 in the direction of the arrow Q to mount the crankshaft W on the fixed block 13. Then, after the support of both ends of the crankshaft W is released by the center (not shown), the moving beam 20 is moved for one cycle, and the quenched crankshaft W is transferred to the fixed block 14 of the aftercooling station 4. The second and third crankshafts W are mounted on the fixed blocks 13 and 12, respectively. The fourth crankshaft W is mounted on the fixed block 11. The crankshaft W on the fixed block 14 is sequentially carried out of the induction hardening device through a quenching standby position of a journal (not shown), a quenching position, and a quenching standby position again.

FIG. 12 is a time chart for obtaining a so-called tact time when the pins P1 to P4 of a large number of crankshafts W are hardened by the induction hardening device as described above. In the figure, the horizontal axis represents time (seconds), the horizontal line represents the duration of each operation, and the numerical value in parentheses below the horizontal line represents the duration of each operation in seconds. The letters on the horizontal lines respectively indicate the contents of the operation. The starting point TO on the horizontal axis is the time when the movement of the moving beam 20 in the direction of the arrow A is started, and at this time the operation of the crankshaft W mounted on the fixed block 12 of the idling station 2 is targeted. I am trying.

In FIG. 12, A, B, C, and D are movement operations of the moving beam 20 in the directions of arrows A, B, C, and D shown in FIG. 11, E is a centering operation of both ends of the crankshaft W, and F is a chucking operation at one end, G is a movement operation of the crankshaft W from the quenching standby position 3A to the quenching position 3B, H is a lowering operation of the heating coil 30, J is an energizing operation to the heating coil 30, and K is Coolant injection operation from the jackets 31, 31, L is a raising operation of the heating coil 30, M is a moving operation of the crankshaft W from the quenching position 3B to the quenching standby position 3A (the crankshaft on the fixed block 13) (W mounting operation), N indicates a chucking release operation at one end of the crankshaft W, and P indicates a centering release operation at both ends of the crankshaft W, respectively.

As shown in FIG. 12, operations A, B, C, D,
The times required for E, F, G, H, J, K, M, N, and P are 1.5, 2, 1.5, 2, 2, 1, 1, 2, 3 respectively.
, 12, 10, 3, 2, 1, and 1 second. Therefore,
After the crankshaft W mounted on the fixed block 12 of the idling station 2 reaches the quenching standby position 3A by the movement of the moving beam 20, the crankshaft W is moved to the quenching position 3B by the hands 38, 38 and then quenched. Next, it takes 41 seconds before returning to the quenching standby position 3A and releasing the support by the hands 38, 38. This 41 seconds is the time when quenching the pins P1 to P4 of the many crankshafts W. It's tact time.

[0011]

[Problems to be Solved by the Invention] In recent years, competition in the induction hardening industry is becoming more and more intense, and in quenching the crankshaft, the tact time is shortened as much as possible.
It has been extremely strongly desired to reduce the quenching cost. The present invention has been made in view of the above circumstances, and an object thereof is to provide an induction hardening apparatus for a crankshaft, which can shorten the takt time when hardening many crankshafts. .

[0012]

According to a first aspect of the present invention, there is provided an induction hardening method for a crankshaft, wherein an unhardened crankshaft at a hardening standby position is moved to a hardening position through a first path and is hardened. The first step of moving the quenched crankshaft in the quenching position to the quenching standby position via the second path, and the first step of quenching the unquenched crankshaft moved to the quenching position in the quenching position. During the 2nd step and the 2nd step, the quenched crankshaft that has been moved to the quenching standby position is carried out, and the unquenched crankshaft is moved from the previous stage of the quenching standby position to the quenching standby position. And a third step of carrying in.

According to a second aspect of the present invention, there is provided an induction hardening apparatus for a crankshaft, wherein a quenching machine for a crankshaft provided at a hardening position and a crankshaft are supported, and a crankshaft of an unquenched crankshaft is moved to a hardening waiting position. From the quenching position of the crankshaft, which has already been quenched, to the
A crankshaft support moving device that simultaneously moves to the quenching standby position through the road, and the quenched crankshaft that has been moved to the quenching standby position is carried out and the quenching standby is performed from the previous stage of the quenching standby position. And a crankshaft conveying device for carrying in an unquenched crankshaft.

The induction hardening device for a crankshaft according to claim 3 is the induction hardening device for a crankshaft according to claim 2, wherein the crankshaft support moving device is
A crankshaft support portion that supports and rotates two crankshafts that are arranged so as to be parallel to one horizontal axis and face each other at an equal distance from the horizontal axis, and are supported by the crankshaft support portion. And a crankshaft rotating portion for rotating the crankshaft around the horizontal axis to move between the quenching standby position and the quenching position.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of an induction hardening apparatus capable of realizing the method of the present invention will be described below with reference to the drawings. 1 to 10 are drawings for explaining this embodiment,
1 is a front explanatory view, FIG. 2 is a side explanatory view, and FIG. 3 is an X of FIG.
-X line arrow cross-sectional explanatory view, FIG. 4 is a Y-Y line arrow cross-sectional explanatory view of FIG. 2, FIGS. 5 to 8 are operation explanatory diagrams, FIG. 9 is a time chart, and FIG. 10 is a front view of the crankshaft. is there. Note that the figure
The same or similar operations as those described with reference to FIG. 11 and FIG. 12 are denoted by the same reference numerals, and description thereof will be omitted. Further, as the work, the crankshaft W described in FIG.
The case of quenching P1 to P4 will be described.

In the induction hardening apparatus of this embodiment, similarly to the induction hardening apparatus described in the prior art, a hardening station including a carry-in station 1, an idling station 2, a hardening waiting position 3A and a hardening position 3B. There are station 3 and after-cooling station 4, and at quenching position 3B, jackets are provided as quenching machines for pins P1 to P4 respectively.
Four heating coils 30 provided with 31, 31 are provided.
In addition, this induction hardening device is used as a crankshaft conveying device and has the same fixed block as described in the related art.
11 to 14, a moving beam 20 provided with moving blocks 21 to 24, a moving beam lifting device 28, and a moving beam forward / backward moving device 29. Further, the induction hardening apparatus is provided with a crankshaft support moving device 300.

The crankshaft support moving device 300 shown in FIGS. 2 to 4 grips the crankshaft W at the quenching standby position 3A, moves it to the quenching position 3B via the semicircular first path EP, and The quenched crankshaft W is moved to the quenching standby position 3A via the semicircular second path FP, and at the quenching standby position 3A, centering and release of both ends of the crankshaft W, and the crankshaft W by a chuck.
Of the crankshaft W at the quenching position 3B and rotation about the axis V of the crankshaft W are performed.

The crankshaft support moving device 300 will be described in detail. Crankshaft support moving device 300 has 1
It is provided with a pair of crankshaft supporting portions 310, 320 and a crankshaft rotating portion 330.

The crankshaft rotating portion 330 is a pair of bearings fixed on the installation surface G of the induction hardening apparatus of this embodiment.
A rotary shaft 11 rotatably supported by 12, 13;
The bearings 12 and 13 are provided with substantially rectangular parallelepiped bases 14 and 15 fixed to the rotating shaft 11 and a known roller cam indexing device 17 disposed on the installation surface G. Roller cam indexer 17
The output shaft 19 is connected to one end of the rotary shaft 11 via a flange coupling 16. Reference numeral 18 is an input shaft of the roller cam indexing machine 17. Further, 10 is an axis of the rotating shaft 11.

The crankshaft support portion 310 includes a base 14
A tail stock 104 fixed on the top, a center 101 attached to the tail stock 104 so as to move back and forth, a chuck control mechanism 108 fixed on the base 15, and attached to one end side of the chuck control mechanism 108. Center 10
2, chuck 103 and gear 105 attached to the other end
And a crankshaft rotating motor 107 fixed to the upper surface of the chuck control mechanism 108, and a gear 106 meshing with the gear 105 and attached to the output shaft of the motor 107.

The crankshaft support portion 320 includes the base 14
The tailstock 204 is fixed 180 degrees above the tailstock 104 and the tailstock 204
The center 201 is attached to the base 15 so as to move back and forth, the chuck control mechanism 208 is fixed on the base 15 at a position facing the chuck control mechanism 108 by 180 degrees, and the chuck control mechanism
Center 202 and chuck 20 attached to one end of 208
3, a gear 205 attached to the other end, a crankshaft rotation motor 207 fixed to the lower surface of the chuck control mechanism 208, and a gear 206 meshed with the gear 205 and attached to the output shaft of the motor 207. Is equipped with.

The chuck control mechanism 108 advances and retracts the center 102 to support and release one end of the crankshaft W, and the chuck 103 causes the crankshaft W to move.
The structure is such that one end of the crankshaft is gripped and released, and the crankshaft W is rotated about its axis V via the chuck 103 in response to the rotation of the gear 105. The chuck control mechanism 208 has a similar structure.

Power is supplied to the motors 107 and 207 and to the electric control circuits of the chuck control mechanisms 108 and 208, which are not mentioned above, through a slip ring (not shown) provided on the rotary shaft 11. Be seen. In addition, the centers 101, 102
The supply of hydraulic pressure required for advancing and retracting the valves 201, 202, etc. is performed via a rotary joint also provided on the rotary shaft 11. Further, instead of attaching the motors 107 and 207 to the chuck control mechanisms 108 and 208 as described above, respectively, the motor 107 and the gear 106 are removed from the chuck control mechanism 108, and the motor 107 is appropriately independent in the vicinity of the quenching position 3B. And when the crankshaft supporting portion 310 or 320 reaches the quenching position 3B, the gear 106 is moved to the gear 105.
Alternatively, the crankshaft W can be rotated by the motor 107 after engaging with 205. Further, instead of hydraulically moving the centers 101 and 102 forward and backward, a center advance / retract mechanism that includes a motor-driven pinion and a rack that meshes with the pinion, and an interlocking mechanism between the centers 101 and 102 are electromechanical. You can also do this.

The roller cam indexing machine 17 has an input shaft 18
When the output shaft 19 is rotated by, for example, one half,
In this case, the output shaft 19 is accurately halved while the input shaft 18 rotates an intermediate part of the input shaft except for the first 20 ° and the last 20 °, for example. It is designed to rotate. Therefore, rotate the input shaft 18
When rotating 19 and the start position of the rotation of the input shaft 18,
The rotation stop position is from the specified start point and end point, respectively.
Even if the output shaft 19 is deviated within the range of 20 degrees, the output shaft 19 accurately performs a predetermined number of rotations corresponding to the rotation speed of the input shaft 18.

Next, the operation of this embodiment will be described. Less than,
When the crankshaft is generally called, it is called a crankshaft W, and the first, second, third, ... Which are sequentially carried into the induction hardening apparatus of the present embodiment for hardening.
.. for crankshafts W1, crankshaft W2, and crankshaft W3, respectively
, ......... 5 (a) and 6 (b), FIGS. 7 (a) and 7 (b), and FIGS. 8 (a) and 8 (b) show the operations of steps S0 to S6, respectively. FIG.

In step S0, the crankshaft moving device 300 provided in the quenching station 3 is operated by the center 101,
102 is on the bottom, centers 201, 202 are on the top, and centers 101 and 201 are on one vertical line,
It is positioned. First, by using a manipulator or the like (not shown), the pin P1
Crankshaft W placed in the lowest position
1 and W2 are arrows A, B, and B of the moving beam 20, respectively.
One cycle of movement in the directions C and D is repeated twice, and the blocks are placed on the fixed blocks 13 and 12. After that, the next crankshaft W3 is placed on the fixed block 11. The crankshaft W1 is connected to the centers 101, 10
After supporting both ends by 2, the chuck 103 grips one end.

In step S1, the input shaft 18 of the roller cam indexing machine 17 is rotated a predetermined number of times to output the output shaft 19
Is rotated exactly 1/2 rotation, that is, 180 degrees, and the crankshaft W1 is moved in the direction of arrow E on the semicircular first path EP to move to the quenching position 3B.

In step S2, each heating coil 30 is lowered in the direction of arrow R and placed on the pins P1 to P4, and then the motor 107 is moved.
The heating coil 30 is energized for a predetermined time while the crankshaft W1 is rotated by starting the
The cooling liquid is sprayed from 31 to the pins P1 to P4, and the quenching of the pins P1 to P4 is completed. When this quenching is finished, the motor 107 is stopped and each heating coil 30 is raised to its original position. During quenching of the crankshaft W1, the moving beam 20 makes one cycle of movement and the crankshafts W2, W3 are mounted on the fixed blocks 13, 12 respectively. Then, after both ends of the crankshaft W2 are supported by the centers 201 and 202, one end is gripped by the chuck 203. Further, the fixed block 11 has a crankshaft W4
Is placed.

In step S3, the roller cam indexing machine 17 is operated as described above to move the crankshaft W1 over the semicircular second path FP in the direction of arrow F to the quenching standby position 3A. Then, the crankshaft W2 is placed on the fixed block 13, and the crankshaft W2 is moved on the first path EP in the direction of arrow E to the quenching position 3B.

In step S4, after each heating coil 30 is lowered, the crankshaft W2 is rotated, and heating and cooling similar to the heating and cooling performed on the crankshaft W1 is performed on the crankshaft W2 for quenching. Then, each heating coil 30 rises. While the heating coils 30 are descending, the one end of the crankshaft W1 by the chuck 103 is released, and then the centers 101 and 102 are released.
The support at both ends is released. Also, during quenching of the crankshaft W2, the moving beam 20 makes one cycle of movement, and the crankshafts W1, W3, and W
After mounting 4 on the fixed blocks 14 to 12, respectively, both ends of the crankshaft W3 are supported by the centers 101 and 102, and then one end is gripped by the chuck 103. A crankshaft W5 is mounted on the fixed block 11.

In step S5, the roller cam indexing machine 17 is operated to move the crankshaft W2 over the second road FP in the direction of arrow F to the quenching standby position 3A and onto the fixed block 13. While being placed, the crankshaft W3 is moved in the direction of arrow E on the first path EP to move to the quenching position 3B.

In step S6, after the heating coils 30 are lowered, the crankshaft W3 is rotated and quenching is performed in the same manner as the crankshaft W1. Then, each heating coil 30 rises. While each heating coil 30 is descending, the gripping of one end of the crankshaft W2 by the chuck 203 is released, and then the support of both ends by the centers 201 and 202 is released. Also, during quenching of the crankshaft W3, the moving beam 20 makes one cycle of movement to place the crankshafts W2, W4, and W5 on the fixed blocks 14 to 12, respectively, and then to the crankshaft W4. Both ends are supported by the centers 201 and 202, and then one end is gripped by the chuck 203. A crankshaft W6 is mounted on the fixed block 11.

Thereafter, the crankshaft W3 is returned to the quenching standby position 3A in the same manner as described above, and then the crankshafts W4, W5, W6, ... Are sequentially quenched and sent to the aftercooling station 4. To be As described above, step S3 and step S4 are the same operations as step S1 and step S2, respectively.
Also, step S5 and step S6 are the same operations as step S1 and step S2, respectively. Further, it can be seen that the total process of step S1 and step S2 is one cycle process when quenching the pins P1 to P4 of one crankshaft W. Therefore, the takt time of the quenching operation of the pins P1 to P4 of the crankshaft W is the total time of step S1 and step S2.

FIG. 9 shows a part of the above operation in a time chart. In the figure, the horizontal axis represents time (seconds), the horizontal line in the figure represents the duration of each action, and the numerical value in parentheses below each horizontal line indicates the duration of each action in seconds. Also, the letters and numbers on the horizontal line are the contents of the operation and the number of the crankshaft that is the target of this operation, respectively, for the first, second, third, ... , 1, 2, 3, ...

A to N and P in FIG. 9 represent operations, and these operations are the operations A to B described in FIG. 11, respectively.
The operation is the same as N and P. However, in the operation G in FIG. 9, the crankshaft W moves from the quenching standby position 3A to the first road.
This is an operation of moving on the EP in the direction of arrow E to reach the quenching position 3B. In operation M, the crankshaft W moves from the quenching position 3B on the second road FP in the direction of arrow F to perform quenching. This is an operation to reach the standby position 3A.

Further, the operations A, B, C, D, shown in FIG.
The time required for E, F, G, H, J, K, M, N, and P is the same as the time required for the operations shown in FIG. 11 corresponding to these operations, and 1.5, 2, 1.5 ,twenty one ,
One, two, three, twelve, ten, three, two, one, and one second.
The starting point TO on the time axis is the starting point of step S1.

As can be seen from FIG. 9, since the time of step S1 is 2 seconds and the time of step S2 is 28 seconds, the takt time is 30 seconds. This is the takt time 41 for quenching the pins P1 to P4 in the conventional induction hardening equipment.
It is 11 seconds shorter than the second, which is a reduction of about 27%.

[0038]

As described above, in the crankshaft induction hardening method and apparatus of the present invention, the unquenched crankshaft at the hardening standby position is moved to the hardening position via the first path. At the same time, after moving the quenched crankshaft at the quenching position to the quenching standby position via the second path, the unquenched crankshaft moved to the quenching position is quenched at the quenching position. Then, while the quenching is being performed, the quenched crankshaft that has been moved to the quenching standby position is carried out, and the unquenched crankshaft is moved from the preceding stage of the quenching standby position to the quenching standby position. Move to.
Therefore, according to the induction hardening method and apparatus of the present invention,
The takt time of the quenching process of the crankshaft can be shortened as compared with the conventional induction hardening device for the crankshaft.

[Brief description of drawings]

FIG. 1 is a front explanatory view of an embodiment of an induction hardening apparatus that can realize the method of the present invention.

FIG. 2 is a side view illustrating an example of an induction hardening apparatus that can realize the method of the present invention.

3 is a cross-sectional view taken along the line XX of FIG.

FIG. 4 is a cross sectional view taken along the line YY of FIG.

FIG. 5 is an operation explanatory view of an embodiment of the induction hardening apparatus capable of realizing the method of the present invention, showing step S0.

FIG. 6 is an operation explanatory view of an embodiment of an induction hardening apparatus that can realize the method of the present invention, and FIGS. 6 (a) and 6 (b) show steps S1 and S2, respectively.

FIG. 7 is an operation explanatory view of an embodiment of an induction hardening apparatus that can realize the method of the present invention, and FIGS. 7 (a) and 7 (b) show steps S3 and S4, respectively.

FIG. 8 is an operation explanatory view of an embodiment of an induction hardening apparatus that can realize the method of the present invention, and FIGS. 8A and 8B show steps S5 and S6, respectively.

FIG. 9 is a time chart of the operation of an embodiment of the induction hardening apparatus that can realize the method of the present invention.

FIG. 10 is a front view of a crankshaft.

FIG. 11 is a front explanatory view of a conventional induction hardening apparatus for a crankshaft.

FIG. 12 is a time chart of the operation of the conventional induction hardening apparatus for a crankshaft.

[Explanation of symbols]

 11-14 Fixed block 20 Moving beam 21-24 Moving block 28 Moving beam lifting device 29 Moving beam forward / backward device 3A Quenching standby position 3B Quenching position 30 Heating coil 31 Jacket 101, 102, 201, 202 Center 103, 203 Chuck 300 Crankshaft support moving device 310, 320 Crankshaft support part 330 Crankshaft rotation part EP 1st road FP 2nd road W, W1-W6 crankshaft

Claims (3)

[Claims] 1. A non-quenched crankshaft at a quenching standby position is moved to a quenching position via a first path, and a quenched crankshaft at the quenching position is moved to a quenching position via a second path. A first step of moving to the quenching standby position; a second step of quenching the unquenched crankshaft moved to the quenching position at the quenching position; and a quenching step during the progress of the second step. A third process of unloading the quenched crankshaft that has been moved to the quenching standby position and transporting the unquenched crankshaft from the preceding stage of the quenching standby position to the quenching standby position.
A method of induction hardening a crankshaft, comprising: 2. A quenching machine for a crankshaft, which is provided at a quenching position, and a crankshaft supporting the crankshaft, and a non-quenched crankshaft moving from a quenching standby position to the quenching position through a first path. A crankshaft supporting and moving device for simultaneously moving the quenched crankshaft from the quenching position to the quenching standby position passing through a second path; An induction hardening of a crankshaft, comprising: a crankshaft carrying device for carrying out a crankshaft and carrying a non-quenched crankshaft from the preceding stage of the quenching standby position to the quenching standby position. apparatus. 3. A crankshaft support moving device for supporting and rotating two crankshafts arranged parallel to one horizontal axis and facing each other at an equal distance from the horizontal axis. And a crankshaft rotating portion for rotating the crankshaft supported by the crankshaft supporting portion around the horizontal axis to move between the quenching standby position and the quenching position. Item 2. An induction hardening device for a crankshaft according to item 2.