RU2299789C2 - Chuck for screw taps - Google Patents

Abstract

FIELD: machine engineering, threading tools.

SUBSTANCE: chuck includes stem onto threaded part of which housing is screwed on. In central opening of housing guiding part of holder is arranged. Lower part of Said holder with seat for tap passes opening of lid joined to housing. In order to enhance accuracy and reliability of adjusting torque, mean part of holder has large diameter and it is embraced by fluid-tight casing. In space between said casing and holder elastomeric material is placed. It is possible to change spacing between end of threaded part of stem and mean part of holder. Silicone may be used as elastomeric material. Lid may be joined with housing by means of bolts passing through elastomeric material. Large-diameter mean part of holder may be provided with tapered portions or with recesses. Flat may be formed on threaded part of holder.

EFFECT: enhanced accuracy and reliability of torque adjustment.

5 cl, 3 dwg

Description

The invention relates to mechanical engineering and can be used for threading a tap.

Known mandrel for threading a tap (see SU 1238911 A1, class B23G 1/16) containing a shank supporting cartridge for a tap, a mechanism for limiting the longitudinal force on the tap and a mechanism for adjusting to the depth of threading. The disadvantages of the known device include the inability to adjust the magnitude of the torque.

Known cartridge for taps (see SU 1567336, B23G 5/00), consisting of a shank, the housing is screwed onto the threaded part, a holder is placed in the central hole of the housing, the lower part of which with a socket for the tap passes through the hole of the cover connected to the housing.

The disadvantages of this cartridge include low reliability due to the complex design, which includes the operation of the spring and the elastic deformation of the squeezing petals of the sleeve, while the wear of the fixing rollers is not accidental, resulting in a distortion of the torque setting, and ultimately the failure of the cartridge.

The objective of the invention is to increase the reliability and accuracy of torque settings.

The objective is achieved in that the middle part of the holder is made of a larger diameter and covered by a sealed casing, in the space between which and the holder there is an elastomeric material, and the shank is installed with the possibility of changing the distance between the end of its threaded part and the middle part of the holder; for example, silicone is selected as an elastomeric material; the cover is connected to the housing by means of bolts passing through the elastomeric material; the middle part of the holder made with a large diameter, has bevels or recesses; on the threaded part of the shank, a flax is made on which divisions are applied;

Figure 1 shows a longitudinal section of a cartridge for taps; figure 2 is a section along aa in figure 1; figure 3 is a view of B in figure 1 (without covering parts).

The cartridge consists of a shank 1, on the threaded cylindrical part of which the housing 2 is placed, and in the inner, central hole - the upper guide part of the holder 3 coaxially to the socket 4 for the tap (not shown), the middle part of the holder 5, made of a large diameter, having bevels or recesses 6, covered by a sealed casing 7, mounted on the housing 2 by means of bolts 8, a cover 9, in the opening of which is placed the lower part 10 of the holder. Between the casing 7 and the middle part of the holder 5 is placed an elastomeric material 11, for example silicone. A lock nut 12 interacts with the housing 2, and a flange is made on the threaded part of the shank 1, on which the divisions 13 are applied.

The cartridge works as follows.

A tap is fixed in the socket 4, the necessary torque is set on the divisions 13 by rotation of the shank 1 relative to the housing 2, this position is fixed with a lock nut 12. The tap is ready for operation, then the tap is brought to the part and the thread is cut.

Changing the size "B" between the ends of the threaded part of the shank 1 and the middle part of the holder 5 affects the pressure of the material 11 on the middle part of the holder 5, because a change in the volume of space occupied by the elastomeric material 11 changes its density, and hence the resistance to movement of bolts 8. It directly affects the amount of transmitted torque from the shank 1, mounted in the spindle of the machine to the holder 5, with a tap installed in its socket 4. If the set moment is exceeded, the housing 2 with the casing 7 and the cover 9 will scroll relative to the holder 5. Thus, the breakage of the tap is eliminated, and the absence of mechanical parts simplifies the design and increases the reliability of the cartridge.

Claims (5)

1. A cartridge for taps, consisting of a shank, the housing is screwed onto the threaded part, in the central hole of which the guide part of the holder is placed, the lower part of which with a socket under the tap passes through the hole of the cap connected to the body, characterized in that the middle part of the holder is made larger diameter and covered by a sealed casing, in the space between which and the holder is placed elastomeric material, and the shank is installed with the ability to change the distance between the end of its threaded part and the medium It part of the holder. 2. The cartridge according to claim 1, characterized in that, for example, silicone is selected as the elastomeric material. 3. The cartridge according to claim 1, characterized in that the cover is connected to the housing by means of bolts passing through the elastomeric material. 4. The cartridge according to claim 1, characterized in that the middle part of the holder, made with a large diameter, has bevels or recesses. 5. The cartridge according to claim 1, characterized in that on the threaded part of the shank is made flat, on which the division is applied.

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