JPH0957590A - Pin grinding device and its method for crankshaft - Google Patents

Abstract

PROBLEM TO BE SOLVED: To measure a position of a crank pin in relation to a crank journal in a pin grinding device. SOLUTION: Grinding work is performed by a grinding wheel 31 in such a state that a crankshaft 19 rotates about a crank pin 29, while the work diameter of the crank pin 29 is measured by movable probes 41, 43. After completing the work, the movable probes 41, 43 are made to position in the outer circumferential parts of the crank pin 29 in the opposite side to each other, which crosses at right angle with a surface containing respective central axes of a crank journal and the crank pin 29, and a phase angle θ of the crank pin 29 to the crank journal is measured based on displacement of the movable probes 41, 43 in the direction opposed to each other. The dimension L between the crank pin 29 and the crank journal 23 is measured in such a state that the movable probes 41, 43 are positioned in the outer circumferential parts of the crank pin 29 in the opposite sides to each other and in parallel to a surface containing respective central axes of the crank pin and the crank journal.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a crankshaft pin grinding device and a pin grinding method for grinding a crankpin in a crankshaft used in an internal combustion engine or the like.

[0002]

2. Description of the Related Art Crankshafts for internal combustion engines (Automobile Engineering Complete Book, Vol. 19, Manufacturing Method for Automobile, pages 105-106)
Page As of April 20, 1980, published by Sankaido), there is a pin grinding process for grinding crankpins with a grindstone. In the pin grinding step, grinding is performed by rotating the crank pin to be machined with the crank journal clamped. FIG. 6 is a diagram showing a state in which pin grinding is performed in the pin grinding device, as viewed from the axial direction of the crankshaft.

The crankshaft 2 has crank journals 2 at both axial ends clamped by chucks (not shown). In this state, the crankshaft 1 rotates about a crank pin 3 to be machined, and a crank 5 is used to crank the crankshaft 1. The outer peripheral surface of the pin 3 is ground. In this grinding process, the machining diameter of the crank pin 3 is measured by the in-process gauge 7. In the in-process gauge 7, two arms 11 and 13 are attached to a gauge body 9,
A fixed measuring element 15 and a movable measuring element 17 are provided on the surfaces of the arms 11 and 13 that face each other.

The above-mentioned in-process gauge 7 monitors the change in the machining diameter of the crank pin 3 based on the displacement amount of the movable probe 17, switches the grinding feed speed of the grindstone 5 for each predetermined dimension, and completes the machining. The (fixed size) is monitored and the grindstone 5 is retracted. FIG. 7 is a flowchart showing the processing operation of the pin grinding device.

First, the in-process gauge 7 is moved forward so that the pair of gauge heads 15 and 17 come into contact with the outer peripheral surface of the crank pin 3 (step 701), and then the grindstone 5 is brought close to the crank pin 3. Move to grinding. The grinding feed of the grindstone 5 at this time is according to the measurement value of the in-process gauge 7, a fast feed for rough machining (step 703), a medium feed for semi-finishing machining (step 705), and a final finishing machining. The microfeed (step 707) is divided into three stages.
Next, when the crank pin 3 reaches the processing completion dimension (fixed dimension) (step 709), the grindstone 5 is retracted (step 711) and the in-process gauge 7 is also retracted (step 713).

[0006]

By the way, in order to secure the processing accuracy in the above-described pin grinding device, there is the position of the crank pin 3 with respect to the crank journal 2 in addition to the processing diameter. The position of the crank pin 3 is defined by the phase angle θ with respect to the crank journal 2 and the dimension between the central axis lines of the crank pin 3 and the crank journal 2, that is, the 1/2 stroke L corresponding to half of one stroke of the piston. There are two types.

However, the above-mentioned two types of crank pins 3,
The so-called pin position cannot be confirmed by the pin grinding device shown in FIG. 6, but is confirmed by a sampling inspection, that is, in a process different from the pin grinding process. Will end up making a lot of defective products.

Therefore, the present invention provides a pin grinding device,
The purpose is to be able to measure the position of the crank pin relative to the crank journal.

[0009]

In order to achieve the above object, the present invention firstly provides a grinding tool for grinding the outer peripheral surface of the crankpin while rotating the crankshaft about the crankpin. A pin grinding device for a crankshaft, comprising: a measuring tool for measuring the outer diameter of the crankpin by contacting a pair of measuring elements at positions facing each other on the outer peripheral surface of the crankpin on which the grinding process is performed. In the above, in the crank journal of the crankshaft and the crankpin in the direction orthogonal to a plane including each central axis of the crankpin, a pair of measuring elements of the measuring tool are arranged on outer peripheral portions of the crankpin, which are opposed to each other. Based on the displacement amount of the child in the direction opposite to each other, the shift amount of the phase angle of the crank pin with respect to the crank journal is measured. A.

Secondly, a grinding tool that grinds the outer peripheral surface of the crank pin while rotating the crank shaft about the crank pin, and a grinding tool that opposes each other on the outer peripheral surface of the crank pin that has been grinded. In a pin grinding device for a crankshaft, which comprises a pair of gauges contacting each other at a position to measure the outer diameter of the crankpin, and a plane including the crank journal of the crankshaft and the central axes of the crankpins. In the outer peripheral portions of the crankpin in the direction parallel to each other facing each other, a pair of tracing stylus in the measuring tool is arranged, based on the amount of displacement of the pair of tracing stylus in the direction opposite to each other, the crankpin and It is configured to measure the amount of dimensional deviation from the crank journal.

Thirdly, while the crankshaft is rotated around the crankpin, a pair of contact points come into contact with each other at positions facing each other on the outer peripheral surface of the crankpin to measure the outer diameter of the crankpin. Meanwhile, the outer peripheral surface of the crank pin is ground, and after completion of this grinding,
Based on the amount of displacement of the pair of probes in the mutually opposing outer peripheral portions of the crankpin in the direction orthogonal to the plane including the central axes of the crank journal and the crankpin of the crankshaft, in the mutually opposing directions. Then, a pin grinding method for measuring a deviation amount of the phase angle of the crank pin with respect to the crank journal.

Fourth, while the crankshaft is rotated about the crankpin, a pair of contact points contact each other at positions facing each other on the outer peripheral surface of the crankpin to measure the outer diameter of the crankpin. Meanwhile, the outer peripheral surface of the crank pin is ground, and after completion of this grinding,
Based on the amount of displacement of the pair of probes in the mutually opposing outer peripheral portions of the crankpin in a direction parallel to the plane including the central axes of the crank journal and the crankpin of the crankshaft, in the mutually opposing directions. And a pin grinding method for measuring the amount of dimensional deviation between the crank pin and the crank journal.

According to the first configuration or the third method, the phase angle of the crank pin with respect to the crank journal can be measured by the probe for measuring the outer diameter of the crank pin during the grinding process. Sampling inspection is unnecessary, or the sampling inspection frequency can be reduced, and the occurrence of defective products due to abnormal phase angles is reduced.

According to the second configuration or the fourth method, the dimension between the crank pin and the crank journal is measured by the probe for measuring the outer diameter of the crank pin during the grinding process.
That is, since 1/2 stroke can be measured, the sampling inspection for confirming the 1/2 stroke is unnecessary, or the sampling inspection frequency can be reduced, and the occurrence of defective products due to abnormal 1/2 stroke is reduced.

[0015]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a side view corresponding to FIG. 6 in a pin grinding device according to an embodiment of the present invention, and FIG. 2 is a main shaft portion of a pin grinding device holding a crankshaft 19 rotatably. FIG. The main shaft portion includes a main shaft 21 that is rotationally driven and a crank journal 23 (23a, 23b, 23c, 23) of the crankshaft 19.
(d, 23e) which is provided with an eccentric chuck 25 for clamping the crank journals 23a, 23e at both ends in the axial direction, and a crankshaft phase angle switching mechanism 27 provided inside the eccentric chuck 25 on the left side in FIG. . The crankshaft phase angle switching mechanism 27 includes the crankpin 2
9 for measuring the phase angle θ with respect to the crank journal 23 and the 1/2 stroke L, which is the dimension between the central axes of the crank pin 29 and the crank journal 23, is used to position the crankshaft 19 by itself. The phase angle can be calculated by numerical control.

The pin grinding device described above grinds the crank pin 29 while the crank journal 23 is clamped, but here, the crank pin 29a, 29d is ground. Therefore, the spindle 21
The center of rotation of the crank pins 29a, 29d at the left and right ends
To match. In this state, the rotation of the main shaft 21 causes the crankshaft 19 to move to the crank pins 29a, 2
Crank pin 2 rotating eccentrically around 9d and rotating
The outer peripheral surfaces of 9a and 29d are ground with a grindstone 31 as a disc-shaped grinder shown in FIG.

The grindstone 31 is movable in the left-right direction in FIG. 1, that is, in the direction toward and away from the crankpin 29. On the opposite side of the grindstone 31, an in-process gauge 33 as a measuring tool is provided with a crankpin. It is arranged so that it can move toward and away from 29. The in-process gauge 33 includes a gauge body 35 and two arms 37 and 39.
Is mounted, and differential transformer type movable measuring elements 41 and 43 are provided at the tips of the arms 37 and 39, respectively, which come into contact with mutually opposing portions of the outer peripheral surface of the crankpin 29.

The above-described in-process gauge 33 can measure the outer diameter (working diameter) of the crankpin 29 during grinding with the grindstone 31 as well as that shown in FIG. , The crank pin 2 mentioned above
9 with respect to the crank journal 23 and 1
The / 2 stroke L can be measured by the difference between the voltages applied to the movable measuring elements 41 and 43.

On the side where the in-process gauge 33 is arranged, the lower work rest 45 that supports the lower side of the crank pin 29 that is being ground and the side work that supports the side opposite to the grindstone 31 are provided. Rests 47 and 47 are provided respectively.

In the pin grinding apparatus constructed as described above, as in the case of FIG. 6, the in-process gauge 33 changes the machining diameter of the crank pin 29 according to the displacement amount of the movable measuring elements 41 and 43. The grinding feed speed of the grindstone 31 is monitored for each predetermined size, and the grindstone 31 is retracted by monitoring the machining completion size (fixed size). FIG.
It is a flowchart showing the operation of the pin grinding device,
The operation from the forward movement of the in-process gauge 33 (step 701) to the backward movement of the grindstone 31 (step 711) is the same as in the flowchart of FIG.

After the grindstone 31 is retracted, the crankshaft phase angle switching mechanism 27 switches the phase angle of the crankshaft 19 (step 713) for positioning, and the phase angle θ of the crankpin 29 with respect to the crank journal 23 is measured. (Step 715). The phase angle switching by the crankshaft phase angle switching mechanism 27 is related to the measurement operation of the phase angle θ of the crank pin 29, as shown in FIG. The positions are arranged so as to face each other in a direction orthogonal to the plane A including each central axis. In this state, a displacement amount of the central axis of the crank pin 29 with respect to the plane A is obtained by the displacement amount of each movable probe 41, 43 with respect to the arms 37, 39, and the crank of the crank pin 29 is determined based on the displacement amount. It is possible to measure the shift amount of the phase angle θ with respect to the journal 23.

After the phase angle θ is measured, the phase angle of the crankshaft 19 is switched again by the crankshaft phase angle switching mechanism 27 (step 717), and the dimension between the central axes of the crank pin 29 and the crank journal 23 is measured. In other words, the process shifts to the measurement of 1/2 stroke L corresponding to half of one stroke of the piston (step 719). The phase angle switching by the crankshaft phase angle switching mechanism 27 at the time of this measurement is performed by the pair of movable gauge heads 41 and 43 as shown in FIG. The pins 29 are arranged so as to face each other in a direction parallel to the plane A including the respective central axes. In this state, the distance between the central axes of the crank pin 29 and the crank journal 23, that is, ½, depending on the amount of displacement of the movable measuring elements 41 and 43 with respect to the arms 37 and 39.
The stroke L can be measured. 1/2 stroke L
After the measurement of, the in-process gauge 33 is retracted (step 721), whereby the series of work up to the crank pins 29a, 29d in the pin grinding device is completed.

When grinding the crank pins 29b and 29c and measuring the phase angle θ and the 1/2 stroke L, the crank pins 29b and 29c are used.
so that the crankshaft 19 rotates about c
The eccentric chuck 25 allows the crank journals 23a, 2
Clamp 3e.

As described above, in the pin grinding device,
The movable probe 41, 43 for measuring the outer diameter (machining diameter) of the crank pin 29 allows the phase angle θ of the crank pin 29 with respect to the crank journal 23 and the crank pin 2 to be measured.
Dimension between 9 and crank journal 23, ie 1
Since the / 2 stroke L can be measured, the sampling inspection for confirming the phase angle θ and the 1/2 stroke L becomes unnecessary, or the sampling inspection frequency can be reduced, and the pin of the phase angle θ or the 1/2 stroke L can be reduced. Occurrence of defective products due to abnormal position is reduced.

[0026]

As described above, according to the first invention or the third invention, the phase angle of the crankpin with respect to the crank journal is measured by the probe for measuring the outer diameter of the crankpin during the grinding process. Therefore, the sampling inspection for confirming the phase angle becomes unnecessary, or the sampling inspection frequency can be reduced, and the occurrence of defective products due to the abnormal phase angle can be reduced.

According to the second invention or the fourth invention, the dimension between the crankpin and the crank journal is measured by the probe for measuring the outer diameter of the crankpin during the grinding process.
That is, since the 1/2 stroke can be measured, the sampling inspection for confirming the 1/2 stroke becomes unnecessary, or the sampling inspection frequency can be reduced, and the occurrence of defective products due to abnormal 1/2 stroke can be reduced.

[Brief description of drawings]

FIG. 1 is a side view showing a state in which pin grinding is performed by using a pin grinding device according to an embodiment of the present invention.

FIG. 2 is a front view of a main shaft portion that rotatably holds a crankshaft in the pin grinding device of FIG.

FIG. 3 is a flowchart showing an operation of the pin grinding device of FIG.

4 is an operation explanatory view showing a phase angle measuring operation in the pin grinding apparatus of FIG. 1. FIG.

5 is an operation explanatory view showing a 1/2 stroke measuring operation in the pin grinding apparatus of FIG. 1. FIG.

FIG. 6 is a side view showing a state in which pin grinding is performed using a pin grinding device according to a conventional example.

7 is a flowchart showing the operation of the pin grinding device of FIG.

[Explanation of symbols]

 19 Crank shaft 23 Crank journal 29 Crank pin 31 Grindstone (grinding tool) 33 In-process gauge (measuring tool) 41, 43 Movable probe

Claims (4)

[Claims] 1. A grinding tool that grinds the outer peripheral surface of the crank pin while rotating the crank shaft around the crank pin, and positions facing each other on the outer peripheral surface of the crank pin that is being grinded. In a pin grinding device for a crankshaft, which comprises a pair of probes contacting each other to measure the outer diameter of the crankpin, a crank journal of the crankshaft and a plane including the central axes of the crankpins are orthogonal to each other. A pair of measuring elements of the measuring tool are arranged on the outer peripheral portions of the crankpin in opposite directions, and the crank of the crankpin is determined based on the amount of displacement of the pair of measuring elements in the mutually opposing directions. A crankshaft pin grinding device characterized by being configured to measure a deviation amount of a phase angle with respect to a journal. 2. A grinding tool that grinds the outer peripheral surface of the crank pin while rotating the crank shaft around the crank pin, and positions facing each other on the outer peripheral surface of the crank pin that is being grinded. A pin grinder for a crankshaft, comprising: a measuring tool for contacting a pair of measuring elements to measure the outer diameter of a crankpin; and a crank journal of the crankshaft and a plane including respective central axes of the crankpin. A pair of gauge heads in the measuring tool are arranged on outer peripheral portions of the crank pin in different directions, and the crank pin and the crank journal are arranged on the basis of the amount of displacement of the pair of gauge heads in the mutually opposite directions. A pin-grinding device for a crankshaft, which is configured to measure the amount of dimensional deviation between 3. The outer diameter of the crank pin is measured while the crank pin is rotated about the crank pin and a pair of probes contact each other at positions facing each other on the outer peripheral surface of the crank pin, Grinding is performed on the outer peripheral surface of the crank pin, and after the grinding is completed, the crank journal of the crank shaft and the outer periphery of the crank pin in the direction orthogonal to the plane including the center axes of the crank pins are opposed to each other. A pin grinding method for a crankshaft, comprising: measuring a shift amount of a phase angle of the crank pin with respect to a crank journal, based on a displacement amount of the pair of tracing stylus arranged in a section in a direction facing each other. 4. A crankshaft is rotated about a crankpin, and a pair of probes contact each other at positions facing each other on the outer peripheral surface of the crankpin to measure the outer diameter of the crankpin, Grinding is performed on the outer peripheral surface of the crank pin, and after the grinding is completed, the crank journal of the crank shaft and the outer periphery of the crank pin in the direction parallel to the plane including the center axes of the crank pins are opposed to each other. A pin grinding method for a crankshaft, characterized in that the amount of dimensional deviation between the crankpin and the crank journal is measured based on the amount of displacement of the pair of stylus elements arranged in the opposite direction in the mutually opposing direction. .