JPS6247667B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a spring grinding machine, and more particularly to an automatic grindstone position correction device that corrects the position of a grindstone according to the amount of wear of the grindstone.

In an automatic spring grinder that uses a grindstone to polish both ends of a coil spring, if the rough grinding wheel is worn out when finish grinding is performed after rough grinding, rough grinding cannot be performed sufficiently.

If the rough grinding of the spring is not done sufficiently, an excessive load will be placed on the grinding wheel for finishing grinding, which will cause significant wear on the grinding wheel for finishing grinding, resulting in a situation where the spring cannot be ground to the desired spring height during finishing grinding. arise.

In addition, even if the desired spring height is achieved during rough grinding, if the finishing whetstone becomes worn during the final grinding stage, the spring will not be ground sufficiently and the desired spring height may be reduced. A situation arises in which the material is not ground properly. An object of the present invention is to provide a spring grinding machine that can quickly detect such a situation and correct it immediately.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The configuration of the present invention will be described in detail below with reference to embodiments shown in the accompanying drawings.

1 is a disk-shaped work table, and spring holding holes 3a and 3b, which serve as spring holding parts for holding the coil spring 2, are provided on the outer periphery of the work table.
are arranged in two transparent rows around the entire circumference at appropriate equal intervals. The work table 1 is connected to an appropriate rotational drive system (not shown) and is supported horizontally so as to rotate in the counterclockwise direction of rotation of the hour hand in FIG.

4a and 4b are a pair of disc-shaped rough grinding wheels (third
(see figure), which is connected to an appropriate rotational drive system (not shown) separate from the rotational drive system to be rotatable in a predetermined direction, and is connected to a drive device shown in FIG. They are supported so that they can move relatively toward and away from each other. Reference numeral 5 indicates the rough grinding wheels 4a, which sandwich the work table 1;
4b, a pair of finishing grindstones (the lower grindstone is not shown) are arranged to be rotatable and movable in the approaching and separating directions. Reference numeral 11 represents a machine base, and reference numeral 6 represents a support shaft, the lower end of which is fixed to a fixed tube 7. The fixed tube 7 is fixed to the base 11. A substrate 9 is fixed to the base 11, and the substrate 9 is arranged at a predetermined distance from the lower surface of the work table 1. A dial cap member 12 having a generally cylindrical overall shape is fitted onto the upper end of the support shaft 6 and secured with screws. 18 is a screw shaft rotatably supported in a fixed position by the cap member 12, to which the dial cylinder 14 is fixed;
A handle 17 is fixed to the upper end of the screw shaft 18. A nut 21 is screwed into the thread of the screw shaft 18, and a key member 23 is fixed to the nut 21 and is slidably disposed in a long hole 22 extending in the axial direction of the shaft 6.

The key member 23 includes support plates 25a and 25b.
A support tube 25 having an integrally extending support tube 25 is fixed with a screw. The support tube 25 is slidably fitted onto the outer peripheral surface of the shaft 6.

A screw hole is screwed at the tip of the support plate 25a,
A long hole 27 is formed through this, and a fixing plate 28 having the long hole 27 formed therethrough is screwed to this.

Therefore, the fixing position of the fixing plate 28 is the elongated hole 2.
It is freely displaceable in the direction toward and away from the support shaft 6, that is, in the radial direction of the work table 1, within an allowable range of 7. A through hole is formed in the thick part of the fixed plate 28 in the thickness direction, into which a bearing member 30 is fitted. Transparent cover members 31, 3
2 is fixed to the fixing plate 28 by screws 33 fastened to the fixing plate 28. 34
A support block is fixed to the fixed plate 28 with screws 35, and one end portion of a square rod-shaped swinging member 36 is supported by a shaft 37 on one side of the upper large block. Reference numeral 38 designates a switch support plate whose one end portion is fixed with a screw 39 to the upper surface of the support block 36, and a screw hole provided in the thickness direction of the end portion on the handle tube side has a thread carved on the outer periphery. The switch 40 is screwed onto the switch piece 4 of the switch 40.
0a and the swinging member 36 are positioned and fixed by a nut 41 so as to be positioned with an appropriate distance therebetween. In this embodiment, a touch switch is used as the switch 40, but a proximity switch or any other commercially available switch may be used. Between the switch support plate 38 and the swinging member 36 are screws 42 and 4 screwed therein, respectively.
A spring 44 having both ends fitted to the switch supporting plate 38 and the swinging member 3 is disposed.
6 in the direction of separation.

Reference numeral 45 denotes a stopper screw screwed onto the switch support plate 38, the tip of which is connected to the swinging member 3.
6, and prevents the swinging member 36 from swinging in the counterclockwise direction of rotation of the hour hand in FIG.

Reference numeral 46 denotes an elevating shaft that is supported by the bearing member 30 so as to be able to move up and down.
It is connected to the swinging member 36 by fitting into a long hole 47 that is transparently provided near the branch of the shaft 37 to extend in the width direction. A circular disk member 46b is fixedly provided. The overlong spring detection device 90 is configured by each of the above components. And this disc member 4
The fixing plate 28 is positioned so that the spring retaining hole 6b is located directly above the moving path of the spring holding hole 3a on the outer peripheral side of the work table 1. The distance between the switch piece 40a and the swinging member 36 is determined by the distance from the axis of the horizontal shaft 46a of the lifting shaft 46 to the axis of the shaft 37, and the distance from the axis of the shaft 37 to the tip of the swinging member 36. The ratio of the distance to the spring 2 held in the spring holding hole is
This is set considering that the distance from the upper end to the bottom surface of the disk member 46b (that is, the allowable range value of the spring height) is approximately equal to the ratio of the distance between the contact shaft 40a and the singing member 36. . For example, if the longitudinal ratio of the swinging member 36 described above is 1:5 and the allowable range value is 0.5 mm, it is desirable that the interval be set slightly smaller than 2.5 mm.

The support plate 25b also has a fixed plate 48, a lifting shaft 49,
A support block 50, a swinging member 51, a switch support plate 52, a touch switch 53, etc. are provided, and constitute an overlong spring detection device 92. And a disk member (not shown) of the elevating shaft 49
The fixing plate 48 is positioned so that it is located directly above the movement path of the spring holding hole 3b on the inner peripheral side of the work table 1. Therefore, compared to the support plate 25a, this support plate 2
5b extends longer in the direction of the work table.

Next, based on FIG. 3, a description will be given of a drive device mainly for correcting the grinding amount of the grindstone, that is, a drive device that drives the grindstone in the direction toward and away from the work table surface. An alarm device 54 such as an alarm lamp or an alarm buzzer is electrically connected to the touch switches 40 and 53.
The swinging member 36 comes into contact with the contact shaft 40a and pushes it, and when the touch switches 40, 53 are turned on, the ON signal lights up a lamp and, in the case of a buzzer, sounds.

Further, the touch switches 40 and 53 are connected to the input end of a preset counter 80, and the output end of the preset counter 80 is connected to a solenoid valve 56 via a timer 55, and to a solenoid valve 57. 81 is a clock pulse generator, 82
is a preset counter, which is configured to supply a pulse to the reset end of the preset counter 80 every time a predetermined number of pulses are counted. The solenoid valves 56 and 57 are connected to an appropriate hydraulic circuit (not shown), and are operated by the output pulse signal of the preset counter 80. At this time, the solenoid valve 56 is configured to operate a predetermined time later than the solenoid valve 57 due to the action of the timer 55. Reference numeral 58 denotes a hydraulic rotary cylinder whose output shaft is set to rotate by a predetermined rotation angle when a pulse is supplied to the electromagnetic valve 56, and a drive bevel gear 59 is linked to the output shaft. A driven bevel gear 60 meshes with the driving bevel gear 59, and is connected to the screw rod 63 via an electromagnetic clutch 83 and gears 61 and 62. 64 is a nut member having a screw hole that is screwed into the screw rod 63;
is supported by a guide member so as to be able to freely slide vertically and not rotate. An upper grindstone head 65 is fixed to the nut member 64, and this grindstone head 6
5 rotatably supports a rotating shaft 66 to which the upper grindstone 4a is connected. The upper surface grindstone 4a is rotated in a predetermined direction by linking this rotating shaft 66 with the aforementioned appropriate rotational drive system (not shown). Note that 64 is a manual handle for rotating the gear 61. 68 is a rotating cylinder, 84 is an electromagnetic clutch, 72 is a handle,
77 is a screw rod, 75 is a nut member, 76 is a grindstone head, 4b is a lower grindstone, 69 and 70 are bevel gears, and 71 and 86 are gears.

Next, the operation of the present invention will be explained.

First, the preset counter 80 is set to 3, and the counter 82 is set to 2 for 120 pulses, for example.
Set to output a pulse every minute. Furthermore, each disk member 46b (one is not shown)
The fixing plates 28 and 48 are positioned so that they are positioned exactly above the movement path of the spring holding holes 3a and 3b, and then screwed onto each support plate 25 with screws 29.
a, 25b. Then, each disc 46 is placed at a height position based on the top surface of the substrate 9, which is the desired spring height after rough grinding plus the allowable range value.
Adjust the height position of each fixing plate 28, 48 so that the bottom surface of b is located. To make this adjustment, the handle 17 is rotated in a predetermined direction. Handle 17
When the nut 21 rotates, the nut 21 moves up and down in accordance with the direction of rotation of the handle 17, and the support tube 25 also moves up and down, so that the fixing plates 28 and 48 also move up and down.

After adjusting the horizontal and vertical positions of the disc member 46b with respect to the work table 1 as described above, the grinding work is started in the same manner as in the conventional spring grinding machine. That is, each spring holding hole 3a, 3 is filled with a coil spring automatic supply device.
Each spring 2 automatically inserted into b is first roughly ground by rough grindstones 4a and 4b, and then finished by a finishing grindstone 5 after passing directly under the disk portion 46b. . For example, if the spring 2 in the spring holding hole 3a after rough grinding has been ground to a desired height, it will pass under the disk portion 46b without coming into contact with it, but the grinding wheels 4a and 4b will be worn out and If both ends of the coil spring that have passed through the coil springs 4a and 4b are not sufficiently polished and the spring height exceeds the allowable range, the coil spring 2 will come into contact with the disk portion 46b and push it upward. Therefore, the elevating shaft 46 rises, and the swinging member 36 swings about the shaft 37 in the direction of rotation of the hour hand in FIG. Push the shaft 40a upward. This turns touch switch 40 ON.
This signal pulse is sent to the alarm device 54, which activates to warn that rough grinding is insufficient. When the spring 2 passes, the swinging member 3
6 and the elevating shaft 46 are returned to their original states by the elasticity of the spring 44 in preparation for the next detection operation.

Further, the signal pulses of the touch switch 40 are input to the preset counter 80, and three pulses are input to the preset counter 80 within two minutes.
When the preset counter 80 is inputted to is excited at a predetermined time difference. Therefore, first, the rotating cylinder 68 is rotated by a predetermined angle in a predetermined direction,
This driving force is transmitted to the nut member 75 via the driving bevel gear 69, driven bevel gear 70, electromagnetic clutch 84, gears 71, 86, screw rod 77,
The lower grindstone 4b is raised by the amount of wear. Subsequently, after a predetermined period of time, the rotating cylinder 58 rotates in a predetermined direction, and this driving force is transmitted to the upper grinding wheel head 65 via the driving bevel gear 59, driven bevel gear 60, gears 61 and 62, threaded rod 63, and nut member 64. ,
The upper grindstone head 65 is lowered by the amount of wear on the grindstone. In this way, both grindstones 4a, 4b can be corrected and moved a predetermined distance in the approaching direction in order to grind to a desired spring height.
This close movement of both grindstones 4a and 4b is performed by a timer 5.
5, the spring 2 to be ground and both grindstones 4a, 4 are ground one by one with a predetermined time difference.
No excessive load is placed on b. In addition, the electromagnetic clutches 83 and 84 are disconnected, and each handle 67 and 7
By rotating the grinding wheel 2 in a predetermined direction, the amount of grinding of the grindstone can be corrected manually as described above.

The solenoid valves 56 and 57 control the grinding wheel 4 based on the output pulse of the preset counter 80.
A control means is configured to supply a control signal for moving the grinding wheels 4a, 4b in a direction in which the grinding wheels 4a, 4b approach each other by a predetermined amount to a drive device that drives the grinding wheels 4a, 4b in the approaching/separating directions.

Note that the present invention can be applied not only to a grindstone for rough grinding but also to a grindstone for finishing, and the device for detecting the spring height of a coil spring is not limited to that of the above embodiment, but can also be applied to a photoelectric element or other device. It may be something you have used. Further, the drive device is not limited to a rotary cylinder using hydraulic pressure, but may also be pneumatic. It goes without saying that the above embodiments can be modified in various ways.

In this way, according to the present invention, the distance between the upper and lower grinding wheels is automatically corrected only when a predetermined number of springs having a spring height larger than the desired spring height after grinding appear within a predetermined time. Operate. Therefore, even if a spring with a large height happens to appear when the grindstone spacing is appropriate, the grindstone spacing will not change in the approaching direction. If a defective spring accidentally comes out and the drive unit operates to shorten the distance between the grinding wheels, the overall spring height of the other coil springs will be shortened, and the spring will be adjusted to the desired spring height. This results in the inconvenience that grinding cannot be performed.

As described above, the present invention detects when a predetermined number of poorly ground springs appear within a predetermined time, and corrects the grinding amount of the grinding wheel in accordance with this detection operation, so that spring grinding is always good. It has the effect of being able to perform the work.

[Brief explanation of the drawing]

The figures show a preferred embodiment of the present invention, in which Fig. 1 is a plan view of the main parts, Fig. 2 is a longitudinal cross-sectional view, and Fig. 3 shows a detection device, a grindstone, a drive device, and a drive force transmission mechanism. FIG. 4 is a schematic diagram showing the connection relationship, and FIG. 4 is an explanatory diagram. 1...Work table, 2...Spring, 3
a, 3b... Spring holding hole, 4a, 4b...
Rough grinding wheel, 5... Finish grinding wheel, 6...
Axis, 9... Board, 11... Machine stand, 25a, 25b
... Support plate, 28 ... Fixed plate, 34 ... Support block, 36 ... Swinging member, 38 ... Switch support plate, 40 ... Touch switch, 40a ... Switch piece, 44 ... Spring, 46 ... Lifting axis, 4
6b... Disc member, 48... Fixed plate, 49... Lifting shaft, 50... Support block, 51... Swinging member, 52... Switch support plate, 53... Touch switch, 54... Alarm device, 55 ……timer,
56, 57... Solenoid valve 58, 68... Rotating cylinder, 65... Top grinding wheel head, 80, 82...
Preset counter, 81...Clock pulse generator.

Claims (1)

[Claims] 1. A work table that is rotatably supported in a predetermined direction and has a number of equally spaced spring holders on its outer periphery for holding the coil springs to be ground; For grinding the ends of coil springs held perpendicularly to the surface of the work table by each of the spring holding parts, the coil springs being rotatably disposed substantially parallel to the work table so that a portion of the coil springs are positioned substantially parallel to the work table. A pair of grinding paper stones, a drive device that drives the grinding wheel in a direction toward and away from the grinding wheel, and a spring that is ground by the grinding wheel and moved while being held in each of the spring holding parts. In order to detect a spring whose height is larger than a desired spring height and output a pulse signal, an overlong spring detector is provided behind the grinding wheel in the movement path of each spring holding part. and a count value is reset to zero at predetermined time intervals, and the input end is connected to the output end of the overlong spring detection device to count pulses from the overlong spring detection device, and to count the pulses. a preset counter that outputs a pulse signal when the value reaches a preset value; and a control for causing the drive device to move the pair of grinding wheels in a direction in which the pair of grinding wheels approach each other by a predetermined amount based on the output pulse of the preset counter. A grindstone position automatic correction device for a spring grinding machine, comprising a control means for supplying a signal.