JP2925577B2 - Phase indexing device for crank pin grinding machine - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a phase indexing device in a crankpin grinding machine.

<Prior Art> In general, a crankpin grinder for grinding a crankpin of a crankshaft, which is capable of performing phase indexing while a main shaft is rotating, is described in, for example, JP-A-62-15070. It is known as such.

In this type of phase indexing device, a phase indexing shaft for phase-determining a crankpin is inserted into a main shaft, and this phase indexing shaft is connected to a phase indexing motor via a differential mechanism, and the crankpin During the rotation of the spindle for grinding
The phase index motor is held stationary by the differential mechanism, and when the phase of the crank pin is indexed by the phase index motor, the main shaft and the phase index shaft are relatively rotated by a positioning device such as a knock pin. The phase indexing shaft (crank pin) is indexed at a predetermined angular position.

<Problems to be Solved by the Invention> In the above-described phase indexing device, a positioning device such as a knock pin is required for determining the phase of the crankpin, which not only complicates the structure of the phase indexing device. However, there is a problem in that the phase index angle of the crankpin is limited, and the phase index of an arbitrary angle cannot be performed.

<Means for Solving the Problems> The present invention has been made to solve the above-described problems, and has a pair of headstocks arranged on a table so as to face each other.
Equipped with a chuck for supporting the spindle on these headstocks so as to be rotatable on the same axis, and supporting the journal at an eccentric position on the end face of the spindle to hold the crankpin of the crankshaft on the axis of rotation of the spindle. An indexing shaft that is rotatable relative to the main shaft coaxially with the main shaft, and an engaging portion that engages with a pin hole formed at one end of a crankshaft is provided at a tip of the indexing shaft; In a crank pin grinding machine provided with a phase indexing device for phase indexing, the phase indexing device includes a phase indexing motor, a first gear meshing with a gear provided on the main shaft, A second gear meshing with a gear provided on the index shaft;
The output shaft of the phase indexing motor, the first gear and the second gear are connected so as to be able to rotate differentially, and the main shaft and the phase indexing shaft are in a state where the phase indexing motor is stopped. , A differential device having a gear ratio set so as to have the same rotational speed, a control device for controlling the rotation of the phase index motor, and a rotation angle of the phase index motor detected and fed back to the control device. And an encoder, wherein the control device controls the rotation direction of the indexing shaft in the normal and reverse directions in a state where the engagement portion is engaged with the pin hole, and controls the play and the differential device between the engagement portion and the pin hole. And a backlash control means for controlling the phase indexing motor so as to remove backlash and the like of the gear system.

<Operation> With the above-described configuration, at the time of grinding the crankpin, the main shaft and the indexing shaft are rotated at the same rotation speed, and the phase indexing motor is kept stopped. On the other hand, at the time of phase indexing of the crankpin, the indexing shaft is rotated relative to the main shaft by driving the phase indexing motor, and the phase of the crankpin is indexed. Thus, the rotation angle of the phase index motor is detected by the encoder, and when the motor is rotated by a predetermined angle, the rotation is stopped.

<Example> Hereinafter, an example of the present invention will be described with reference to the drawings. First
In the figure, reference numeral 10 denotes a bed on which a grindstone table 11 and a table 12 are slidably mounted in directions orthogonal to each other. The wheel head 11 is moved forward and backward with respect to the table 12 by a ball screw mechanism (not shown) driven by a feed motor 13. A grindstone shaft 15 is rotatably mounted on the grindstone stand 11, and a grindstone drive motor 16
A grinding wheel 17 that is rotationally driven by is mounted.

A pair of left and right headstocks 21 and 22 are arranged on the table 12 so as to face each other, and spindles 23 and 24 are rotatably mounted on the same headstocks 21 and 22 on the same axis. Chucks 25 and 26 are attached to the tips of the spindles 23 and 24, respectively, and journal receivers 27 and 28 that support the journals J1 and J2 of the crankshaft W are provided at eccentric positions of the chucks 25 and 26. Clamp arms 29, 30 for clamping the journals J1, J2 are also pivotally attached to the chucks 25, 26,
One ends of the clamp arms 29, 30 are connected to clamping cylinders formed on the chucks 25, 26.

A gear mechanism is provided on the spindle 23 which is supported by the one headstock 21.
The main shaft drive motor 36 is connected via the main shaft 35, and the driving force of the main shaft drive motor 36 is transmitted to the main shaft 24 via a synchronous shaft (not shown) connecting the main shafts, and the main shafts 23 and 24 are rotated synchronously. It has become so. A gear 37 is provided at the rear end of the spindle 23.
Are fixed concentrically with the main shaft 23.

On the other hand, an indexing shaft 40 is rotatably inserted through the shaft of the main shaft 23, and a gear 41 is fixed to the rear end of the indexing shaft 40 as shown in FIG. The gear 41 is meshed with a second gear 42 rotatably supported on the headstock 21. A transmission shaft 43 is concentrically and rotatably mounted on the second gear 42, and a first gear 44 meshing with the gear 37 is fixed to one end of the transmission shaft 43. An output member 46 of a known differential device 45 having a speed reduction function is coupled to one end of the second gear 42, and an input member 47 of the differential device 45 has a phase indexing motor mounted on the headstock 21. 48 are combined. The other end of the transmission shaft 43 is connected to a revolvable and rotatable member 50 of the differential device 45. An encoder 49 for detecting the rotation angle is connected to the phase index motor 48.

The above-described gear 37, the first gear 44 meshing therewith, the gear
41 and a second gear 42 and a differential gear 45 meshing therewith
The tooth ratio is set such that the main shaft 23 and the index shaft 40 have the same rotational speed when the phase index 48 is stopped. Accordingly, when the main shaft drive motor 36 is driven to rotate the main shaft 23 in a state where the phase indexing motor 48 is stopped, the rotation of the main shaft 23 is performed by the gears 37 and 44, the differential device 45, and the gears 42 and 41. The phase indexing shaft 40 is transmitted in order, and rotates at the same rotation speed as the main shaft 23.

At the tip of the indexing shaft 40, an indexing pin 51 that engages with a pin hole W1 formed in the end face of the journal J1 is provided, and the indexing pin 51 is pressed by a spring 52 so as to be able to advance and retreat. .

On the other hand, the table 12 is reciprocated by a ball screw mechanism (not shown) driven by a feed motor 53, and indexes each crank pin to be ground at a position corresponding to the grinding wheel 17.

Drive circuits 60 and 61 are connected to the feed motors 13 and 53, respectively, and the drive circuits 60 and 61 are connected to a numerical controller 62.
(Central processing unit) 63 via pulse distribution circuits 64 and 65. This CPU 63 has an interface 6
7 and the memory 66 are connected. The grindstone drive motor 16, the spindle drive motor 36, and the phase indexing motor 48 are connected to the interface 67 via motor control circuits 68, 69, 70, respectively. A current detection circuit unit 71 is connected between the motor control circuit 70 and the phase index motor 48,
The output signal is input to the interface 67. Furthermore, the interface 67 has a phase index motor
It is connected to an encoder 49 connected to 48.

Next, an operation at the time of phase indexing in the above configuration will be described. When a machining command is given in a state where the journals J1 and J2 of the crankshaft W are mounted on the chucks 25 and 26, the phase indexing motor 48 is started, and the differential device 45
The index shaft 40 is rotated in one direction (positive direction) via the second gear 42 and the gear 42. When the indexing pin 51 corresponds to the indexing hole W1 of the crankshaft W by the rotation of the indexing shaft 40, the indexing pin 51 is engaged with the indexing hole W1, and the crankshaft W is integrated with the indexing shaft 40. Start to rotate.
When the encoder 49 detects that the phase index motor 48 has been rotated by a predetermined angle, the rotation of the phase index motor 48 is stopped. In this state, the clamp arms 29 and 30 are rotated by the clamp cylinder, and the journals J1 and J2 are clamped. Subsequently, the phase indexing motor 48 is rotated in the opposite direction to the above, and the indexing shaft 40 is rotated in the reverse direction. At this time, the amount of rotation allowed for the indexing shaft 40 is determined by the indexing pin 51 and the indexing hole W1. And the backlash of the gear system of the phase indexing device. When the backlash and the backlash are removed, the load current of the phase index motor 48 increases. The current increase at this time is detected by a current detection circuit, and when the load current exceeds a certain value, the phase index motor 48 is stopped, and the detection signal of the encoder 49 at this time is updated as the origin signal. In this way, the phase of the specific crankpin on the crankshaft W is determined on the rotation axis of the main shaft 23. Thereafter, the spindle drive motor 36 is driven, and the grinding of the crankpin whose phase is determined on the rotation axis of the spindle 23 is started.

When the grinding of the crankpin is completed, the spindle 23 is stopped at a certain angular position, and then the clamp arm 2 is stopped.
9,30 is opened and journals J1 and J2 are unclamped. When the journals J1 and J2 are unclamped, the phase indexing motor 48 is again rotated in the reverse direction. The rotation of the phase index motor 48 is detected by the encoder 49, and when it is rotated by a predetermined angle, for example, 180 °, the rotation of the phase index motor 48 is stopped and servo locked. At this time, since the origin of the encoder is set in a state where the play between the index pin 51 and the index hole W1 and the backlash of the gear system are removed, the play is not affected by the play and the backlash. The phase of the crankshaft W can be determined with a high degree of accuracy by a predetermined angle. Thereafter, the crankshaft W is clamped in the same manner as described above, and the crankpin is ground.

<Effects of the Invention> As described above, according to the present invention, two sets of gears and a differential gear having a gear ratio set so that the indexing shaft has the same rotation speed as the main shaft during rotation of the main shaft are provided. The control device controls the rotation of the index shaft in the forward and reverse directions in a state in which the engaging portion of the index shaft is engaged with the pin hole of the crankshaft. The backlash control means for removing the backlash etc. of the gear system including the above allows the phase indexing motor to be held in a stopped state during rotation of the main shaft, and the rotation angle of the phase indexing motor to the encoder. And the angle of rotation of the phase index motor is controlled, eliminating the need for a conventional positioning device for determining the phase, simplifying the configuration, and allowing the crank pin to rotate at any angle. There is an effect that phase indexing can be performed.

[Brief description of the drawings]

FIG. 1 shows an embodiment of the present invention. FIG. 1 is an overall view of a numerically controlled crankpin grinding machine, FIG. 2 is a configuration diagram of a numerically controlled crankpin grinding machine, and FIG. It is a principal part expanded sectional view of FIG. 11 ... Whetstone head, 12 ... Table, 21,22 ... Headstock, 23,
24 ... Spindle, 25,26 ... Chuck, 36 ... Spindle drive motor, 40 ... Indexing shaft, 37,41,42,44 ... Gear, 45 ... Differential device, 48 ... Phase indexing Motor, 49 …… encoder,
62 ... Numerical control unit.

Continuing from the front page (72) Inventor Nishio 1-1-1 Asahi-cho, Kariya-shi, Aichi Prefecture Inside Toyota Koki Co., Ltd. (72) Inventor Tsunaichi Murayama 1-1-1, Asahi-cho, Kariya-shi, Aichi Prefecture Toyota Koki stock In-house examiner Hiroshi Ogawara (56) References JP-A-62-15070 (JP, A) JP-A-1-27839 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) B23Q 3/18 B24B 5/42 B23Q 16/02 B23B 31/10

Claims (1)

(57) [Claims] 1. A pair of headstocks are arranged on a table so as to face each other, a main shaft is rotatably mounted on the headstocks so as to be rotatable on the same axis, and a crankpin of a crankshaft is attached to an end face of these main shafts. Equipped with a chuck that supports the journal at an eccentric position to hold it on the rotation axis of the axis, an index axis that is rotatable relative to the main axis coaxially with the main axis, and a tip of this index axis at one end of the crankshaft. In a crank pin grinding machine provided with an engaging portion that engages with the formed pin hole and provided with a phase indexing device for phase indexing the indexing shaft, the phase indexing device includes a phase indexing motor, A first gear meshing with a gear provided on the main shaft; a second gear meshing with a gear provided on the index shaft; an output shaft of the phase index motor; And the second gear A differential gear that is connected to be rotatably rotatable and has a gear ratio set such that the main shaft and the phase indexing shaft have the same rotational speed when the phase indexing motor is stopped; and A control device that controls the rotation of the motor, and an encoder that detects the rotation angle of the phase indexing motor and feeds back to the control device,
The control device controls the rotation direction of the indexing shaft in the forward and reverse directions in a state where the engagement portion is engaged with the pin hole, and plays back the gear portion including the play between the engagement portion and the pin hole and a differential device. A phase indexing device for a crankpin grinding machine, comprising: a play control means for controlling the phase indexing motor so as to remove rush and the like.