Gear cutting – milling – or planing – Milling – With limit means to aid in positioning of cutter bit or work
Patent
1987-01-27
1989-05-02
Weidenfeld, Gil
Gear cutting, milling, or planing
Milling
With limit means to aid in positioning of cutter bit or work
33638, 33642, 340680, 408 16, B23Q 1522
Patent
active
048263702
DESCRIPTION:
BRIEF SUMMARY
The present invention relates to an indicator device for determining the distance between a workpiece set up in a working machine, and a tool set up in said machine, said device comprising a lower portion with an underside which is adapted to lie against the workpiece, an upper portion with a topside against which the tool is intended to come into contact, said topside being parallel to the underside of the lower portion and movable towards said underside against the effect of a resilient force, a voltage source and an indicator means.
When working workpieces in a machine, such as a milling machine, boring mill, lathe, planer, shaping machine, drill or the like, it is often necessary to determine exactly the distance between the workpiece and the working tool. It is a frequent occurrence that a shank end cutter in a milling machine for example must be removed and replaced because it has become dull or has the wrong dimension for continued working. The problem then arising consists in being able to place the new cutter in exactly the same position relative to the workpiece as the cutter removed.
This problem has been solved previously for milling machines by moving the newly mounted cutter under rotation slowly towards the workpiece, and resetting the zero of the machine scale when the cutter just barely touches the workpiece. If the workpiece has had a precision ground or polished surface or is otherwise easily damaged, it is not possible to rotate the cutter when setting it against said surface. In this case thin brass leaf or the like is placed on the surface of the workpiece, and the cutter is carefully moved into contact with the brass leaf. The scales of the mill are then reset taking into account the thickness of the brass leaf. These two methods have essentially been used to determine the distance between a workpiece and a tool in the above mentioned machine types as well.
The two methods described above have, however, the disadvantages that they are slow, consuming an unnecessary amount of costly machine time, that the sharpened edge of the tool is easily broken particularly when the tool is not rotated, thus necessitating replacement of the tool and repetition of the process, and risk of often irrepairable damage to the workpiece surface. Finally, the above methods are not particularly precise.
Swedish Patent Specification No. 125 907 shows a device for determining the distance between a tool and a workpiece in a machine, within certain intervals. This device comprises a lower portion with an underside which is intended to be attached to the workpiece, and an upper portion with a topside which is parallel to the underside and is intended to make contact with the tool. The upper portion is spring-mounted. The device also comprises a current source and an indicator means, which are arranged so that the indicator means gives different readings as the upper portion is pressed down towards the bottom portion. This device is intended for determining the distance between a tool and a workpiece within certain intervals. Furthermore, this device is made up of a number of different components, which can give rise to variations in the levels at which the indications are sent when used at different times.
In order to correct the above problems, according to the invention there is suggested a device of the above mentioned type which is characterized in that the underside is electrically insulated from the topside, and in that the indicator means and the voltage source are coupled so that the indicator means provides an indication when a circuit between the topside and the underside is closed via the workpiece, the machine and the tool.
One embodiment of the device according to the invention will be described in more detail below with reference to the accompanying drawing, which shows a cross section through the device according to the invention.
As can be seen in the drawing, the device comprises an upper portion 1, a lower portion 2, a spring 3 acting therebetween, a voltage source in the form of batteries 4
REFERENCES:
patent: 816307 (1906-03-01), Eaton
patent: 3270329 (1966-08-01), Schnell
patent: 3481247 (1969-12-01), Hayes
patent: 3553671 (1971-01-01), Hopkins
patent: 3636814 (1972-01-01), Each
patent: 3684939 (1972-08-01), Perry
patent: 4326824 (1982-04-01), Lasermann et al.
Howell Daniel W.
Industriverktyg AB
Weidenfeld Gil
LandOfFree
Indicator device does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Indicator device, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Indicator device will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-581831