JPH01252349A - Device of bringing lens into constant pressure contact with grinding stone of ball sliding machine - Google Patents

Abstract

PURPOSE:To maintain a contact force at a normally specified value, by providing a control means which specifies a difference between a rotational lowering moment by the weight of a carriage body determined from the inclination angle of the carriage body when a coarse grinding lens is brought into contact with a V-grinding stone and a rotational lowering preventing moment by a spring. CONSTITUTION:A radius vector is which a coarse polishing lens L between lens shafts 8 and 9 is brought into contact with a V-grinding stone 4 according to the shaft rotation angles of the lens shafts 8 and 9 is determined by a CPU (control means). The inclination angle of a carriage body 7 when the coarse grinding lens L is brought into contact with the V-grinding stone 4 in the radius vector position is computed by a CPU. From the inclination angle, a rotational lowering moment by the weight of the carriage body 7, exerted on the contact part therebetween, is computed by the CPU. A contact pressure regulating means is driven by the CPU so that a difference between the rotational lowering moment and a rotational lowering preventing moment by a spring is adjusted to a specified value. This constitution maintains a contact force of the lens L with the V-grinding stone 4 at a specified value even when the radius vector of a contact position is changed.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention provides, for example, a method for processing a rough-ground lens held between the lens axes of a swingable carriage body before beveling the edge end of the rough-ground lens. This invention relates to a constant pressure contact device for a lens to a bevel grinding wheel used to determine the position or coordinates of the bevel grinding wheel relative to the V-groove depending on the size of the vector radius.

(Prior Art) There is a conventional beading machine as shown in Fig. 8. In this beading machine, a rough grinding wheel 3 and a bevel grinding wheel 4 are fixed adjacent to a rotary drive shaft 2 provided in the front part of a main body I.

In addition, a rotary drive shaft 2 is provided on the support portion 5 provided at the rear of the main body l.
A support shaft 6 parallel to this is held rotatably and movably in the axial direction, and a rear end portion of a carriage 7 is fixed to this support shaft 6.

Furthermore, a pair of lens shafts 8 and 9 arranged coaxially and parallel to the support shaft 6 are rotatably held at the front end of the carriage 7. This lens shaft 9 is provided so as to be adjustable forward and backward with respect to the lens shaft 8, and by tightening the lens shaft 9, the fabric lens L is fixed between the lens shafts 8 and 9.

Such lens shafts 8 and 9 are provided so as to be driven for synchronous rotation by a pulse motor 10 for rotating the lens shafts within the carriage 7. Further, a template 11 is detachably attached to the end of the lens shaft 8.

Further, when the pulse motor 12 for lateral movement supported by a frame (not shown) is rotated in the forward or reverse direction, the feed screw 1
3 is rotationally driven, and the arm plate 15 supported by the guide shaft 14 moves forward and backward in the direction in which the lens shafts 8 and 9 and the support shaft 6 extend. The arm plate 15 rotatably holds the end of the support shaft 6, and the carriage 7 is driven forward and backward in the axial direction of the support shaft 6 via the arm plate 15 by the operation of the pulse motor 12. Further, a church 16 is held on this arm plate 15 so as to be movable up and down, and a church 16 is held in a movable manner.
A pulse motor 17 is attached to drive the motor 6 up and down. This church 16 has a contact piece 1 on the top of the church body 16a.
6b is attached so as to rotate up and down within a predetermined range around one end, and the contact piece 16b is biased upward by a spring.

When processing a fabric lens L using such a beading machine, the lens shaft 8 is
. This rough-ground material lens L has a radius P from the rotation center to the circumferential surface that differs at each point in the circumferential direction, and both surfaces are three-dimensional curved surfaces as shown in FIG. The edges change in the axial direction of the lens shafts 8 and 9. Therefore, when beveling the peripheral edge of a lens L that has been roughly ground, it is necessary to control the amount of lateral movement of the carriage 7 according to each vector radius /'L. It is not possible to apply a natural finish.

Therefore, in order to satisfy this point, as shown in FIG.
. The axial direction of 8 and 9) and the edge thickness are measured in advance for each radius vector A, and the amount of lateral movement during bevel machining corresponding to each radius vector A is determined. It is considered.

Note that this specific configuration is based on the Japanese Patent Application Laid-open No. 6, which the applicant previously filed.
It is the same as that of No. 2-335672.

(Problem to be Solved by the Invention) When performing such measurements, when the measurement position of the lens L is changed in the circumferential direction, the radius vector a correspondingly changes.

Since the angle of inclination θ of the carriage 7 also changes, if the contact position of the edge end of the lens L, Lb, to the inclined surfaces 18a, 18b is changed in the circumferential direction, the inclination angle θ of the carriage 7 at this time also changes.

However, the edge end of the lens L, the inclined surface 18a of Lb,
Since the contact force to 18b uses the rotational moment due to the weight of the carriage 7, when the tilt angle 0 of the carriage 7 changes, the edge end of the lens L, the inclined surface 18 of Lb
Since the abutting force on the lenses a and 18b becomes large, the abutting force on the sloping surfaces 18a and 18b of the edges of the lens L and Lb is not constant. Such a contact force can be applied even if the contact position of the edge end of the lens Lb and the inclined surfaces 18a and 18b of the lens Lb is moved in the circumferential direction, and the radius vector a at the contact point changes. It is desirable for the grinding pressure to be sufficiently small and always constant in order to perform more accurate 8:s determination.

SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a device for bringing a lens into constant pressure contact with a grindstone for a grinding machine, which satisfies this demand.

(Means for Solving the Problems) In order to achieve this object, the present invention includes a bevel grinding wheel rotatably mounted on the front part of a main body, and a bevel grinding wheel that is driven forward and backward in a direction parallel to the rotation axis of the beveling grindstone. a carriage base that is attachable to the main body and is provided with a support portion; a portion near the rear end is pivotally connected to the support portion via a support shaft parallel to the rotation axis; a carriage body having a center of gravity on the side thereof; a pair of lens shafts provided on the carriage body so as to be able to adjust relative approach and separation coaxially in a direction parallel to the rotation axis and rotatably drive in a direction around the axis; an elastic member having one end attached to one of the rear end of the carriage body and the carriage base; and the other end of the elastic member to the rear end of the carriage body, the other of the carriage base, and the other end of the elastic member. and a contact force adjusting means interposed between the lens shafts, and determining a radius vector at which the rough grinding lens between the lens shafts contacts the beveling grindstone in accordance with the rotation angle of the lens shafts,
Calculate the inclination angle of the carriage body when the rough grinding lens contacts the beveling grindstone at this radial position, and calculate the rotational descent moment due to the weight of the carriage body acting on the contact portion from the inclination angle. a control means for driving and controlling the contact force adjusting means so that the difference between the rotational descent moment and the rotational descent prevention moment by the spring is constant; It is characterized in that it is a device.

(Function) According to such a configuration, [corresponding to the axial rotation angle of the lens shaft, the radius vector at which the rough grinding lens between the lens axes comes into contact with the bevel grinding wheel is determined, and at this radius vector position, the rough grinding The angle of inclination of the carriage body when the grinding lens contacts the beveling grindstone is calculated, and from this angle of inclination, the rotational downward moment due to the weight of the carriage body acting on the contact portion is calculated.

The control means drives the contact force adjusting means so that the difference between this rotational descent moment and the rotational descent prevention moment by the elastic member becomes constant. Thereby, even if the radius vector of the contact position changes, the contact force of the lens against the beveling grindstone remains constant.

(Example) Hereinafter, an example of the present invention will be described based on FIGS. 1 to 7.

FIG. 1 is a perspective view of a polishing machine equipped with a constant pressure contact device for a lens to a grindstone according to the present invention, and is the same as the part shown in FIG. 8.
Otherwise, similar parts will be given the same reference numerals and their explanation will be omitted. Further, the lens edge position is measured in the same manner as in Japanese Patent Laid-Open No. 62-335672, which was previously filed by the applicant.

Therefore, the points that are different from these will be explained in detail below.

A guide shaft 19 extending in a direction parallel to the rotary drive shaft 2 (rotary shaft) of the bevel grinding wheel 4 is attached to the rear part of the main body 1 at a position not shown, and a carriage base 20 is attached to this guide shaft 19 to move forward and backward in the longitudinal direction. Possibly held. The carriage base 20 is connected to the arm plate 15 and is driven forward and backward in the axial direction of the guide shaft 19 by a pulse motor 12 together with the arm plate 15.

Support portions 21° 21 projecting upward are provided at both ends of the carriage base 20 in the moving direction.
．． At the upper end portion of the carriage body 21, the rear end portions 7a and 7a of the carriage 7 are supported by support shafts 22 and 22 arranged coaxially so as to be movable up and down. Note that the center of gravity G of the carriage 7 is located forward of the support shaft 22.

A temple sensor S is interposed between the mold bone body 16a of the temple 16 and the contact piece 16b. Since this cathedral sensor S uses the same detector as that provided in the cathedral of Japanese Patent Application Laid-open No. 62-335672, a detailed explanation thereof will be omitted.

A contact force adjusting means 23 is attached to the rear end 7a of the carriage 7. This contact force adjusting means 23 has a rear end portion 7a.
The pulse motor 24 attached to the
4a, a circular timing plate 25 and a spring attachment lever 26 attached to the rotation shaft 24b, and a microswitch 27 attached to the rear end 7a. A V-shaped notch 25a is formed in the timing plate 25, and a roller 27b at the tip of an actuator lever 27a of the microswitch 27 is in contact with the curved surface of the timing plate 25. When the roller 27a engages with the notch 25a, the microswitch 26 is turned off.

Further, a spring 28 is interposed between the lower end of the lever 26 and the carriage pace 20.

Further, the contact force adjusting means 23 is provided so as to be drive controllable by a CPU 29 (central processing unit) serving as an arithmetic circuit (control means). The output from the microswitch 26 and the signal from the church sensor S are input to the CPU 29. Further, the CPLI 29 controls the rotation time of the pulse motor 24 via the timer 30.

Such a CPU 29 controls the lens axis 8 from the drive control pulse signal of the pulse motor 10 during rough grinding of the lens L.
, 9 are calculated and stored.

In addition, when measuring the positional coordinates of the edge end of the roughly ground lens L, the CPU 29 adjusts the radius vector A of the roughly ground lens L that comes into contact with the beveling grindstone 4 to the axial rotation angle of the lens shafts 8 and 9. In addition, the inclination angle θ of the carriage 7 when the rough grinding lens L contacts the beveling grindstone 4 at this radius vector position is calculated from the determined radius vector p5 and the known carriage arm length. Moreover, the CPU 29 determines the operating time of the timer 30 and the direction of energization to the pulse motor based on the calculation result, and uses the timer 30 to control the energization time and the direction of energization to the pulse motor. At this time, the CPU 29 controls the energization time and the energization direction by turning the micromechanical switch 27 OFF when the roller 27b engages with the notch 25a.
The rotational descent moment due to the weight of the carriage 7 that starts from the position of L, and acts on the contact portion from the inclination angle of the carriage 7 to 0, and this rotational descent moment and the rotational descent prevention by the spring 28. This is done so that the difference from the moment remains constant.

An example of this relationship is as follows: the center of rotation of the carriage 7 is 0, the center of gravity of the carriage 7 is G, and the axis of the lens axis from the center of rotation O is a.
The length from the rotation center O to the center of gravity G is C1, and the length from the rotation center to the point f where the spring force acts is 8 degrees, and at the point f. The acting spring force is F. Let the weight at the center of gravity G be G. Due to the rotational descending moment due to the weight G0, the contact point E of the lens with the beveling grindstone and the axis lv! This will be explained with reference to FIGS. 5 to 7, assuming that the rotational lowering moment acting on the O-yu is vo.

FIG. 5 shows a case where the carriage 7 is horizontal and its inclination angle is zero. In this case, the lens machining radius is a. Then, A-110, C-G, , B・
The relationship of Fo is A-11,+C-Go=Da-F.

becomes.

At this time, the pulse motor is controlled so that the lever is vertically directed downward.

Further, FIG. 6 shows a case where the machining radius a is larger than po. In this case, the length from the rotation center O to the point f where the spring force of the spring acts is [31, and the spring force that acts on the point f is F.
, then the power relationship is A-W, cosO+C-Go
cosθ〉”a'F+cosθA・su.cosO+Cl
G11cosO=B1・F1cosθ′(B, <8
．． ) Make it happen. Therefore, in this case, the lever is rotated away from the rotation center 0.

Furthermore, Fig. 7 shows machining radius a and g. This shows the case where A2 is smaller. In this case, the length from the rotation center O to the point f2 on which the spring force of the spring acts is 82, and the spring force acting on the point f2 is F2.
Then, the power relationship is A-vOCO5O+C-GOC
O8θ<Bo−F2CO8OAHw. cosO+C number G
, cos O=8. Life F, cos O' (B11 > 8
2) Make it happen. Therefore, in this case, the lever is rotated toward the rotation center O.

Note that instead of calculating the inclination angle of the carriage, the first
A rotary encoder IIF for detecting the inclination angle may be attached as shown by the broken line in the figure.

Further, although the spring force of the spring 28 is applied to the carriage 7 by the rotating lever 26, the present invention is not necessarily limited to this. For example, a spring mounting member is attached to the rear end 7a of the carriage 7 so as to be able to move forward and backward with respect to the front end of the carriage 7, and this spring mounting member holds the upper end of the spring 28, and the spring mounting member is The forward and backward movement of the front end of the carriage 7 may be controlled by a motor, cylinder, or the like.

(Effects of the Invention) As explained above, the present invention includes a bevel grinding wheel rotatably mounted on the front part of a main body, and a bevel grinding wheel mounted on the main body so as to be movable forward and backward in a direction parallel to the rotation axis of the beveling grindstone. and a carriage base having a support portion, a portion near the rear end being pivotally connected to the support portion via a support shaft parallel to the rotation axis, and having a center of gravity on the front side of the support shaft. a carriage body, a pair of lens shafts provided on the carriage body so as to be able to adjust relative approach and separation coaxially in a direction parallel to the rotation axis and rotatably drive in a direction around the axis; and a rear end of the carriage body. an elastic member having one end attached to one of the carriage base and the carriage base; and an elastic member interposed between the rear end of the carriage body, the other of the carriage base, and the other end of the elastic member. Determine the radius vector at which the rough grinding lens between the lens axes comes into contact with the beveling grindstone in accordance with the contact force adjustment means and the rotation angle of the lens axis, and adjust the rough grinding lens at this radius vector position. Calculate the inclination angle of the carriage body when it contacts the beveling grindstone, calculate the rotational descent moment due to the weight of the carriage body acting on the abutment part from the inclination angle, and calculate the rotational descent moment and the Since the structure is provided with a control means for driving and controlling the contact force adjusting means so that the difference with the moment for preventing rotation and descent by the elastic member is constant, the edge end of the roughly ground lens is not in contact with the beveling grindstone. The contact force during contact is always kept sufficiently smaller than the processing pressure during lens grinding, even if the contact position of the edge of the lens to the bevel grindstone is moved in the circumferential direction and the radius at the contact point changes. This means that you can do it. Further, this control can be used not only when contacting and measuring the lens edge, but also for adjusting the processing pressure for lens grinding.

Furthermore, instead of the present invention, a method may be considered in which the moment for preventing rotation of the carriage is increased by changing the length of the spring, but in that method, a spring with a large spring constant is used, and the length of the spring is In order to change the spring length, a large torque spring length changing means is required, which is expected to have the disadvantage of increasing the size of the device and consuming energy. In addition, adjusting the spring length alone has a small adjustment range for the blocking moment.1For example, it is impossible to adjust the contact force when measuring the lens edge thickness and the processing pressure during lens grinding using a single mechanism. .

In contrast, the present invention uses a method of changing the point of action (1) of the spring, so the adjustment device is simple, compact, and energy-saving, and the range of the carriage rotation blocking moment can be widened, allowing one adjustment. The mechanism can be used both to adjust the contact force when measuring the lens edge thickness and to adjust the processing pressure when grinding the lens.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of a polishing machine equipped with a constant pressure contact device for a lens to a grindstone according to the present invention. FIG. 2 is an explanatory diagram of the main parts of the beading machine shown in FIG. 1. FIG. 3 is a right side view of FIG. 2. FIG. 4 is a control circuit diagram of the lens constant pressure abutting device shown in FIG. 2. 5 to 7 are explanatory views of the operation of the lens constant pressure contact device shown in FIGS. 1 to 4. FIG. FIG. 8 is a perspective view showing an example of a beading machine. FIG. 9 is an explanatory diagram of the operation of the beading machine shown in FIG. 8. l...Main body, 2...Rotation drive shaft (rotation axis), 3...Rough grinding wheel, 4...Bevel grinding wheel, 7...Carriage, 8, 9...Lens axis,
11... Template, 16... Cathedral, 18.
... V groove, 20... Carriage base, 21.21... Support part, 22.22... Support shaft, 23... Contact force adjustment means, 29... CPU
(control means),...lens. Figure 2 Figure 3 Figure 4 Accent Figure 5 Figure 7 Figure 3 Mouth Figure 9

Claims (1)

[Scope of Claims] A beveling grindstone rotatably mounted on the front part of a main body, and a support portion is provided on the main body so as to be movable forward and backward in a direction parallel to the rotation axis of the beveling grindstone. a carriage base; a carriage body whose portion near the rear end is pivotally attached to the support portion via a support shaft parallel to the rotation axis and whose center of gravity is on the front side of the support shaft; a pair of lens shafts provided on the carriage body such that they can be adjusted relatively toward and away from each other on the same axis in the same direction and rotatably driven in a direction around the axis; and either the rear end of the carriage body or the carriage base. an elastic member having one end attached to one end; a contact force adjusting means interposed between the rear end of the carriage body, the other of the carriage base, and the other end of the elastic member; Determining the radius at which the rough grinding lens between the lens axes comes into contact with the beveling grindstone corresponding to the rotation angle of the lens axes,
Calculate the inclination angle of the carriage body when the rough grinding lens contacts the beveling grindstone at this radial position, and calculate the rotational descent moment due to the weight of the carriage body acting on the contact portion from the inclination angle. a control means for driving and controlling the contact force adjusting means so that the difference between the rotational descent moment and the rotational descent prevention moment by the spring is constant; Device.