Pneumatic brass drift set

Abstract

A set of brass punches compatible with a single steel driver that is formed to cooperate with a pneumatic driving tool wherein each punch includes an identical counterbore construction for receipt of a threaded end of the driver.

Description

CROSS REFERENCE TO RELATED APPLICATION

This is a utility application derived from, incorporating by reference and claiming the priority filing date of Ser. No. 60/568,618 filed May 6, 2004 entitled Pneumatic Brass Drift Set.

BACKGROUND OF THE INVENTION

In a principal aspect, the present invention relates to a set of brass punches or drifts which may be utilized in various environments, for example, in automotive repair for the purpose of driving parts in a manner which will avoid damage to the driven part; particularly when using a pneumatic driver.

Heretofore, there have been various sources of bronze or brass drifts or punches which are utilized for the purpose, for example, of driving pins, shafts or rods from openings or bearings from a position where they are seated or unseated. Typically, such punches or drifts are manually operated or hand operated. That is, they are hand driven by means of a hammer which impinges against one end of the punch or drift so that the opposite end may be driven into engagement with a pin, rod, bearing, etc.

Thus, there has developed the need to provide a brass drift or punch which can be safely pneumatically driven rather than hand driven. Further, there has developed a need to provide a pneumatic brass drift or punch which can be easily replaced or repaired in the event the drift or punch driving end or engaging end becomes damaged.

SUMMARY OF THE INVENTION

Briefly the present invention comprises a set of preformed brass punches or drifts, each of which includes a standard size threaded counterbore or opening with a seat defined at the bottom or inside of the bore and each of which is capable of receipt of a standard, threaded steel, pneumatic driver. The driver includes a first end which is designed for cooperation with a pneumatic tool driver device. The driver further comprises an elongate rod having its opposite end threaded and including a pointed probe or pilot which is adapted to be cooperative with any one of the standard size counterbore openings in a set of distinct brass punches or drifts. Consequently, depending upon the requirements of the particular task to be performed, a brass punch or drift may be selected from a set and threadably attached to the driver. The driver may then be driven by a pneumatic driving tool. The driver is designed so that the threaded section of the driver will permit the pilot end thereof to properly and completely seat within the counterbore defined in the brass punch or drift.

Thus, it is an object of the invention to provide an improved set of brass punches and, more particularly, a set of such punches which may be pneumatically driven.

A further object of the invention is to provide a set of brass punches which may be easily incorporated in combination with a pneumatic driver having a rod-like configuration and which may be threadably coupled to any one in a set of the brass punches or drifts.

Another object of the invention is to provide a set of pneumatic brass punches or drifts which are economical, rugged, and which may be used as punches that are pneumatically driven rather than hand driven.

These and other objects, advantages and features of the invention will be set forth in the detailed description which follows.

BRIEF DESCRIPTION OF THE DRAWING

In the detailed description which follows, reference will be made to the drawing comprised of the following figures:

FIG. 1 is a side view of a driver useful in the combination of the invention;

FIG. 2 is an end view of the driver of FIG. 1;

FIG. 3 is a side view of a first brass punch or drift;

FIG. 4 is an end view of the punch of FIG. 3;

FIG. 5 is a sectional view of the drift of FIG. 4 taken along the line 5-5;

FIG. 6 is a side view of an alternative brass punch or drift;

FIG. 7 is an end view of the brass punch of FIG. 6;

FIG. 8 is a cross sectional view of the punch of FIG. 7;

FIG. 9 is a cross sectional view of an assembled punch and driver.

FIG. 10 is a side elevation of alternative punch construction;

FIG. 11 is a cross-sectional view of the elevation of the punch of FIG. 10;

FIG. 12 is a side elevation of another alternative punch;

FIG. 13 is a side cross sectional view of the punch of FIG. 12; and

FIG. 14 is an isometric view illustrating the manner of use of the driver and a punch of the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring to the figures, the driver depicted in FIGS. 1 and 2 is preferably manufactured from annealed cold steel. The driver 18 includes a driving end 20, a longitudinal axis 22 and a driven end 24. The driven end includes a threaded section 26, a pilot section 28, which is cylindrical, and a frustoconically shaped pilot end 30. The driver 18 is similar to the construction of a driver depicted in U.S. Pat. No. 4,926,537, incorporated herewith by reference. Importantly, the driver is fabricated from a hardened steel such as annealed cold steel having a hardness resulting from heat treatment in the range of about 46-50 austemper.

Cooperative with the driver 20 are various brass punches which are made from a metal composition generally softer than the driver 18. For example, the brass punch illustrated in FIGS. 3-5 is manufactured from a hard temper 464, non-leaded naval brass. The punch 40 includes an active punch end 42, having a diameter, for example, 1/2 inch diameter, a longitudinal axis 44 and a connecting end 46 with a counterbore 48. The counterbore 48 is threaded to be compatible with the threads 26 of the driving end 20 of driver 18. The counterbore 48 includes a lesser diameter, cylindrical section 50 compatible with the cylindrical pilot section 28 of the driver 18. Finally, the counterbore 48 includes a frustoconical section 52 having an included obtuse angle 53 which acts as a seat for engagement by the compatible frustoconical pilot end 30 of the driver 18. As depicted in FIG. 9, the brass punch or drift of FIGS. 3-5 may be threadably attached to the driver 18 with the pilot end 30 seated against the frustoconical surface 52 so that the threads and, in particular, the threads of the brass driver 40, will not be damaged by pneumatic engagement of the driver 18 at driving end 18.

Similarly, referring to FIGS. 6-8, there is depicted a second brass drift or punch 60 which has a longitudinal axis 62 and a symmetrical counterbore 64 substantially identical in construction to the counterbore 48 associated with the punch 40. Thus, the punch 60 may be attached to the driver 18.

Referring next to FIGS. 10 and 11, there is depicted some further embodiments of punches that may be used in combination with the driver 18 previously described. FIGS. 10 and 11 illustrate a first alternative embodiment of a punch. FIGS. 12 and 13 illustrate a further alternative embodiment. Referring first therefore to FIGS. 10 and 11, the embodiment of punch 70 includes a head section 72 and a punch end 74. The punch 70 is symmetrical about a longitudinal axis 76. Thus, the punch 70 includes a counterbore 78 having a threaded section 80, a pilot section 82 and an obtuse angle frustoconical section 84 substantially identical to the counterbores of the previously described punches. An important concept illustrated by the punch of FIGS. 10 and 11 relates to the draft angle of the punch end 74. The draft angle 86 is the inward angle of inclination relative to the longitudinal axis 76 of the surface of the punch end 74. This draft angle is preferably in the range of approximately about 2°. With respect to all of the punches which have a generally circular cross-section face, such as face 88 of the punch 70, wherein the face 88 has a diameter which is less than the diameter of the head section 72, a draft angle has been found to be highly desirable for the punch. Thus, the punches is previously described preferably include a draft angle of the type depicted with respect to the embodiment of FIGS. 10 and 11; namely a draft angle in the range of about 2°.

Referring next to FIGS. 12 and 13 there is illustrated a further example of a punch 90 having a longitudinal axis 92 which is an axis of symmetry for the punch 90. The punch 90 further includes a head end 94 and a punch end 96. The surface 96 has a draft angle in the range again of about 2°. The end face 98 of the punch 90 is generally circular. The counterbore 100 is substantially identical in construction to the counterbore 78 of the punch of FIG. 11. All of the counterbores are substantially identical in construction. As explained previously, the pilot section 102 associated with a counterbore 100 has a depth or longitudinal extent which is generally equal to or less than the longitudinal extent of the pilot end of driver 18. This ensures that the frustoconical end of the drive 18 will seat properly in the punch.

It is preferential that a single driver 18 be included with a set of brass punches of the type described. A full set of brass punches may be comprised of two or more punches having the dimensions generally set forth in Table 1:

Punch Active			Maximum Outside
End Diameter	Punch Length	Taper (Draft)	Diameter
0.375 in.	4 in.	˜2°	1 in.
0.500 in.	4 in.	˜2°	1 in.
0.812	4 in.	˜2°	1 in.
1.000 in.	2 in.	None	1 in.

It is possible of course to add additional punches having different diameters which may be driven by a single driver 18.

Various other sizes of punches or drifts may be utilized in combination with the driver 18. Additionally, the construction of the punches may be varied. The punch 40 has an elongate probe end 42. The probe end 42 is generally cylindrical. Various other shapes, sizes, lengths and the like may be utilized to provide a full set of brass punches for use in combination with the hard steel driver 20. As noted, the hard steel driver is preferably a tempered steel, for example, 46-50 austemper annealed cold steel. In contrast, the brass material associated with the drift or punch is not nearly as hard so as to avoid damaging items against which the brass is driven. Thus, the brass may, as described above, be a hard temper 464 for non-leaded naval brass which is a much softer material relative to the material used to make the driver 18. This is an important functional aspect of the invention. By utilizing soft brass punches, which may be easily damaged from use but which, in turn, will not damage bearings, rods, pins, etc., the punches may be replaced in a set or individually. The driver 18 may be retained. Further, in view of changing needs due to size and standard changes, the punches may be easily replaced. Further, the combination of the hard steel driver 18 and softer brass punch 40 facilitates ease of attachment of the punches and detachment of the punches as contrasted to use of a hard punch material. Also, the brass punches will not spark when driven and may be redressed easily when deformed.

The compactibility of the threaded section 26, pilot section 28, and pilot end 30 of driver 18 with the counterbore 48 is an important feature of the combination. The pilot end 30, for example, has a lesser diameter than the crests of threaded section 26 and cylindrical section 50 of punch 40 is sized and generally congruent with cross-sectional, opening of pilot section or end 30. Pilot end 30 extends longitudinally at equal to or lesser than longitudinal section 50 of punch 40 to insure that the pilot end 30 will seat. The pilot end 30 and punch seat 52 are substantially mirror images of each other to insure seating by full surface contact. Because the frustoconical surfaces comprise an included obtuse angle, they are easily unseated by reverse screw movement.

While there has been set forth a preferred embodiment of the invention, it to be understood that the invention is limited only by the claim therefore.

Claims

1. A pneumatic punch set comprising, in combination:

a driver comprised of a hardened steel member in the form of a longitudinal rod member having a longitudinal axis of symmetry with a driving end including a rod section for receipt of a pneumatic driving tool, a flange for engagement by a pneumatic driving tool, a driven end opposite the driving end, said driven end including a frustoconical shaped seat end with an included obtuse angle, an adjacent cylindrical pilot section, and a further threaded section adjacent the pilot section; and

a set of at least two punches, said punches each including a counterbore driver receiving end with a substantially identical counterbore for receipt of the driven end of the driver, said counterbore including a frustoconical seat fully compatible with the driver frustoconical shaped seat end including substantially the same included obtuse angle, a cylindrical pilot section having a diameter substantially equal to the driver pilot section diameter and a longitudinal length greater than or equal to the driver pilot section longitudinal dimension, and a threaded section compatible with the driver threaded section, the crest diameter of the driver threaded section being greater than the diameter of the driver pilot section, said punches each further including a punch end, having a diameter equal to or less than the outside diameter of the receiving end; at least one of the punches of the set including a punch end with a draft angle of the outside surface with respect to the longitudinal axis in the range of about 2° converging toward the punch end, said punches each comprised of a deformable brass material having a hardness less than the hardness of the driver.