JPS637496Y2 - - Google Patents

Description

[Detailed description of the invention] (Field of industrial application) The present invention is an automatic grinding wheel cover correction device that automatically maintains the gap between the tip of the grinding wheel cover of a cylindrical grinder and the outer periphery of the grinding wheel within a predetermined range. Regarding.

(Prior Art) This type of automatic grinding wheel cover correction device for a grinding machine has a grinding wheel head, a grinding wheel pivotally supported by the grinding wheel head, and a grinding wheel cover that covers at least the upper front half of the grinding wheel. The grinding wheel is supported on the grinding wheel head so as to be movable in a direction orthogonal to the rotational axis of the grinding wheel, and the grinding wheel cover is moved in the orthogonal direction in response to a decrease in the diameter of the grinding wheel due to modification of the grinding wheel. The gap between the tip of the cover and the outer periphery of the grinding wheel is kept within a predetermined range, but the conventional one uses a servo motor on the grinding wheel head side, as shown in JP-A-52-131295, for example. A screw shaft driven by this is provided, and the screw shaft is screwed into a nut on the grindstone cover side.
Each time the radius of the grinding wheel was adjusted, the servo motor was used to move the grinding wheel cover little by little to correct the gap between it and the grinding wheel. However, since this requires a servo motor, a screw shaft, a nut, and other supporting members, the structure becomes complicated, which is an obstacle to reducing manufacturing costs. On the other hand, there are devices in which the screw shaft is rotated by a ratchet wheel device instead of a servo motor, but the above-mentioned problem has not been solved.

(Purpose of the invention) The present invention eliminates the problems of the prior art by moving the grinding wheel cover using a direct-acting ratchet mechanism every time the outer diameter of the grinding wheel decreases by a certain amount.

(Structure of the invention) In order to achieve the above object, the present invention provides a grinding wheel cover automatic correction device for a grinding machine of this type, which includes a direct-acting ratchet mechanism provided between the grinding wheel cover and the grinding head, and a mechanism for adjusting the grinding wheel cover. It is characterized in that the ratchet mechanism is operated to move the grindstone cover by a certain amount with respect to the grindstone head each time the diameter becomes smaller by a certain amount.

(Effects of the invention) This invention uses a direct-acting ratchet mechanism, without using a power transmission means such as a screw shaft,
Since the grindstone cover is directly moved, the mechanical configuration of the automatic grindstone cover correction device can be greatly simplified, and manufacturing costs can be reduced.

(Example) To explain the outline of the present invention using the illustrated example, as shown in FIGS. 1 and 2, a grindstone cover 1
3 covers the front side of the grinding wheel 11, that is, the upper half of the side where the workpiece W is located, and is supported by a grinding wheel guard 12 fixed to the grinding wheel head 10 so as to be movable in the front and rear directions. A movable plate 31 is provided on the upper side of the whetstone cover 13 with the whetstone guard 12 in between, and a direct-acting ratchet mechanism 3 is installed between the whetstone cover 13 and the whetstone guard 12.
Set 0. In the present invention, a direct-acting ratchet mechanism is one in which the driving part and the driven part of the ratchet mechanism are directly connected to the fixed part (or movable part) and the movable part (or fixed part) without going through a power transmission device such as a screw mechanism or link mechanism. ). Grinding wheel 1
1 is corrected by the grinding wheel shaping/correcting device 20 every time a certain number of workpieces W are processed, and the radius R gradually becomes smaller. This radius R is stored in the storage device 61 backed up by the battery, and the stored value is updated every time the grinding wheel 11 is corrected, and every time the value becomes smaller by a certain amount (in this embodiment, the radius R is reduced by 10 mm), the control means 6
0 operates the ratchet mechanism 30 via the interface 63, the switching valve 51, and the cylinder device 50 to retract the grinding wheel cover 13 by one pitch corresponding to a 10 mm reduction in the radius R, and the tip 13a and the grinding wheel 11 are moved back. This is to maintain the gap between the outer periphery of the

Next, details of each part will be explained. Figures 1 and 2
In the figure, a grindstone head 10 is supported so as to be movable in the front-rear direction (left-right direction in FIG. 1) with respect to a bed (not shown), and pivotally supports a grinding wheel 11 which is rotated by a drive device (not shown). A whetstone guard 12 covering the rear half of the whetstone wheel 11 is fixed to a whetstone stand 10, and a top plate 12a of the whetstone guard 12 is provided with a guide hole 12b elongated in the front and back direction. A grinding wheel cover 13 that covers the front upper half of the grinding wheel 11 is brought into contact with the lower side of the top plate 12a, and a movable plate 31 having support legs 31c is brought into contact with the upper side of the top plate 12a, and both of these 13 and 31 are guided. The connecting pin 14 passes through the hole 12b and is welded to the movable plate 31 at its upper end to connect the top plate 12a with the top plate 12a therebetween. Thus, the grindstone cover 13 is the movable plate 31
At the same time, it is supported so as to be movable in the front-rear direction with respect to the grindstone head 10, that is, in the direction orthogonal to the rotation axis of the grindstone wheel 11.

A direct-acting ratchet mechanism 30 provided between the whetstone cover 13 and the whetstone guard 12 is connected to the whetstone cover 13.
It consists of a driven part provided on the side and a driving part provided on the grindstone guard 12 side. The driven part is connected to the connecting pin 14 as described above.
A movable plate 31 connected to the grinding wheel cover 13 via
An engagement plate 31a having engagement teeth 31b is integrally provided on its upper surface. The driving section includes a moving member 34 supported by a cylinder device 50 so as to be able to reciprocate back and forth via a bracket 15 fixed to a grindstone guard 50, and a moving member 34 supported via a pivot pin 36.
The movable pawl 35 is pivotably supported by the movable pawl 35 and is pressed downward by a spring 37, and the riding plate 38 is fixed to the bracket 15 and controls the engagement of the movable pawl 35 with the engagement tooth 31b. The movable member 34 is normally in the position shown in the figure, but if the switching valve 51 is operated in response to a command from the control device 60 (described later), the movable claw 35 is moved by the piston rod 50a of the cylinder device 50.
moves to the right (rear) via the movable member 34, comes off the riding plate 38, engages with the engaging tooth 31b, and moves to the grindstone cover 13 via the movable plate 31 and the connecting pin 14.
Move back by a predetermined distance of 1 pitch (10mm). In addition,
As shown in the figure, a restraint mechanism 40 is provided to prevent the grindstone cover 13 and the movable plate 31 from moving unnecessarily when the movable claw 35 rides on the riding plate 38 and is disengaged from the engagement teeth 31b. The restraint mechanism 40 uses a spring 43 to press downwardly a restraint member 42 supported by a pivot shaft 44 on an upper plate 41, and engages engagement teeth 42a on the lower surface of the restraint member 42 with an engaging pawl 45 fixed to the movable plate 31, so that the movable plate 31 restrains the forward movement of the Thereby, when the grinding wheel 11 is damaged, it is possible to prevent the grinding wheel cover 13 from being moved forward by the damaged grinding wheel. The restraining mechanism 40 is the upper plate 4
1 and can be opened centering on the pivot pin 41b by the handle 41a, and can be maintained in the open state by the support rod 46.

The grinding wheel shaping/correcting device 20 is basically the same as the known one. When making corrections, use the servo motor 25
The feed screw 26 is rotated to advance the ram 23 and give a predetermined depth of cut to the correction tool 24 at the tip. The grinding wheel 11 is moved in a traverse direction parallel to the axis.
Correct the outer diameter of. After the correction is completed, the correction tool 24 is moved back again.

The control device 60 performs the processing shown in FIGS. 3 to 5. First, the grindstone correction process shown in FIG. 3 and the grindstone cover movement process shown in FIG. 4 will be explained. The control device 60 in FIG. 1 operates the grinding wheel shaping correction device 20 to perform grinding wheel correction processing every time a certain number of workpieces W are processed. That is, as shown in FIG.
The grinding wheel 11 is cut by an amount of cut U more than the previous time, the grinding wheel 11 is corrected by traverse movement, the correction tool 24 is then moved backward, and the grinding wheel head 10 is moved forward by the corrected depth of cut U. At the same time, the radius R of the grinding wheel 11 before correction read from the storage device 61 is subtracted by the depth of cut U to obtain the radius R after correction, and this is stored in the storage device 61 to memorize the radius R of the grinding wheel 11. Update the value. Following the above grinding wheel correction process, the fourth
Although the grindstone cover moving process shown in the figure is performed, this does not mean that the ratchet mechanism 30 is operated to move the grindstone cover 13 every time the grindstone wheel 11 is corrected. Every time the radius R of the grinding wheel 11 decreases by 10 mm, the grinding wheel cover 13 is moved back by one pitch, that is, by 10 mm. Based on the initial grinding wheel radius Ro
Value B set every 10 mm and radius R of grinding wheel 11
is read by the storage device 61, B and R are compared, and the control device 60 starts the grindstone only once, immediately after the radius R passes the set value B (at this time, the set value B is updated to B-10). A cover movement signal is generated, and the ratchet mechanism 30 is operated via the interface 63, the switching valve 51, and the cylinder device 50 to move the grindstone cover 13 back by 10 mm. When the set value B is updated successively and becomes less than the final grinding wheel radius Rmin, which is the usage limit of the grinding wheel 11, the grinding wheel 11 is replaced. Before operating the grinding machine after replacing the grinding wheel, the initial grinding wheel radius Ro is previously given to the storage device 61.

In the illustrated embodiment, corrective tool wear correction is performed, so the control device 60 performs the process shown in FIG. 5 every time it receives a sizing signal from the sizing device 64, The stored value of radius R of No. 11 is updated every time machining is performed. As shown in FIG. 5, for each machining process, the position counter value P (indicated by the diameter of the workpiece) of the grindstone head 10 is read out, and the finishing diameter D of the workpiece W stored in advance in the storage device 61 is read out. The difference ε (=D−P) between the two is obtained.
Since the difference ε is mainly the wear amount of the correction tool 24, the difference ε is added to the radius R of the grinding wheel 11 to correct it.
Update the stored value of radius R. Further, the position counter value P is updated to be equal to D and stored, and the position counter P is corrected. In this embodiment, the stored value R of the radius of the grinding wheel 11, which is stored in the storage device 61 while being updated sequentially, does not simply decrease with the number of times the workpiece W is processed, as shown in FIG. While repeating increases and decreases, it gradually decreases as a whole. Therefore, one of the set values B, which is set while updating every 10 mm, is set multiple times during the decreasing process (in Fig. 6, P
1, p2, and p3), it is necessary for the control device 60 to generate the grindstone cover movement signal only during the first pass (p1 in FIG. 6). For this purpose, the section between the set value B and the value A 10 mm before it (= B + 10) is r
The parameter N is divided into areas r1, r2, r3, and r4, and as shown in FIG.
is increased by 1 step each time the grinding wheel is corrected,
In area r3, parameter N is set to 0,
Parameter N is kept unchanged in zone r4, and a grindstone cover movement signal is generated only when the value of parameter N changes from 0 to 1 outside zone r4.

In the above embodiment, the whetstone cover 13 was supported so as to be movable in parallel to the whetstone guard 12, but the upper part of the whetstone cover was supported by a pivot parallel to the whetstone axis so that it could rotate, and the lower part was supported by a direct-acting type. By retreating using a ratchet mechanism, the grindstone cover 13 may be rotated to maintain a gap with the outer periphery of the grindstone within a predetermined range. Although the ratchet mechanism 30 is operated by the cylinder device 50 using fluid pressure, it may be operated by an electromagnetic or other actuator.

Alternatively, a counter may be used to detect that the grindstone has been corrected a certain number of times, and the ratchet mechanism 30 may be operated in response to the output of the counter.

(Effects of Example) In the above example, the driving side of the direct-acting ratchet mechanism 30 is directly attached to the grindstone guard 12, and the driven side is directly attached to the grindstone cover 13, so there is no need for a power transmission means such as a screw shaft. Therefore, its mechanical configuration can be greatly simplified and manufacturing costs can be reduced. The increase in the amount of movement of the grinding wheel cover 13 by using the direct-acting ratchet mechanism 30 means that the movement of the grinding wheel cover 13 is not made every time the grinding wheel 11 is corrected, but by a fixed amount of the radius R of the grinding wheel 11. This can be solved by doing this every time the number decreases, and there is no particular problem.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional view mainly showing the mechanical configuration of an embodiment of the present invention, Fig. 2 is a cross-sectional view taken from Fig. 1, Fig. 3 is an explanatory diagram of the grinding wheel correction process, and Fig. 4 is a grinding wheel cover. FIG. 5 is an explanatory diagram of the movement process, FIG. 5 is an explanatory diagram of the correction process due to wear of the correction tool, etc., and FIG. 6 is an explanatory diagram of the operation of the embodiment. Explanation of symbols, 10... Grinding wheel head, 11... Grinding wheel, 13... Grinding wheel cover, 13a... Tip, 30
. . . Direct-acting ratchet mechanism, 60 . . . Control device (control means), 61 . . . Storage device (storage means), R
...The radius of the grinding wheel.

Claims (1)

[Scope of utility model registration request] It has a grinding wheel head, a grinding wheel pivotally supported by the grinding wheel, and a grinding wheel cover that covers at least the upper front half of the grinding wheel, and the grinding wheel cover is movable in a direction orthogonal to the rotational axis of the grinding wheel. The grinding wheel cover is moved in the orthogonal direction in response to a decrease in the diameter of the grinding wheel due to correction of the grinding wheel, and the gap between the tip of the grinding wheel cover and the outer periphery of the grinding wheel is reduced to a predetermined range. In the automatic grinding wheel cover correction device for a grinding machine, the grinding wheel cover is maintained within the grinding wheel cover, and the grinding wheel cover is maintained within the grinding wheel head. 1. A grinding wheel cover automatic correction device for a grinding machine, characterized in that the grinding wheel cover automatic correction device is provided with a control means that is operated to move the grinding wheel cover by a predetermined amount with respect to the grinding wheel head.