GB2213746A

GB2213746A - Barstock gripper collet

Info

Publication number: GB2213746A
Application number: GB8729686A
Authority: GB
Inventors: Peter Leslie Windley; Graham Keith Thompson
Original assignee: Individual
Current assignee: Individual
Priority date: 1987-12-21
Filing date: 1987-12-21
Publication date: 1989-08-23
Also published as: GB8729686D0

Abstract

The gripper collet comprises a tubular body 1 threaded at one end for attachment is a bar stock puller and has coupled to it a sleeve for gripping the bar stock. As shown, the sleeve has collet segments surrounded by a compressible sleeve. The sleeve can grip the interior of tubular stock with a segmented sleeve around a compressible sleeve on a spigot part. <IMAGE>

Description

Drawing Attached IMPROVEMENTS RELATING TO GRIPPER COLLETS I, Peter Leslie Windley of 414 Quinton Road West, Quinton, Birmingham, England and Graham Thompson of 32 Lakeside Walk, Brookvale, Erdington, Birmingham, England, do hereby declare the invention for which I pray that a patent may be granted to us and the method by which it is to be performed to the particulars described by the following statement.

This invention relates to the type of Gripper Collets fitted to Automatic Bar Loading Magazines.

The traditional gripper collet fitted to these machines comprised a steel tube having a plurality of parallel slots extending along the tube from one end.

The diameter is reduced by closing the slot heat treating to maintain the reduced diameter. In operation Bar Stock is engaged into the closed end and friction grip retains the Gripper Collet on the bar and rotates with it. The function of the Gripper is to retract the remnant end of the Bar Stock for removal and accept a new Bar Stock. The bar stock rotates within a carrier tube and is held by the Gripper at one end and the machine Collet at the other. At high rotation the Bar Stock is subject to skipping rope action, the Gripper is subjected to angular defections which result in fracture.

The disadvantages are that the Collet requires frequent replacement resulting in loss of production and increased costs. The present invention relates to improved Gripper Collets which eliminates the loss of production and clost due to fracture.

The invention accordingly provides a holder suitable for accepting External Gripper devices as follows: A cylindrical body having a threaded bore extending from one end only.

A reduced conical diameter extends from the other end and a larger reduced conical diameter extends further to a midway position. A recessed reduced diameter is placed within the length of the larger conical diameter at the larger diameter end. A plurality of radial holes spaced around the larger conical diameter. Flats are formed on the larger outside diameter. A flexible means is located within the smaller reduced diameter and the reduced conical diameter.The invention accordingly provides an internal gripping device to fit on to the above described holder and suitable for internally gripping the bore of metal or composite material in automatic loaders or like machines which comprises a cylindrical gripper having an external diameter at one end and a reduced external diameter extends from the other end an internal diameter extends part way into the external diameter a reduced internal diameter extends further into the external diameter and a further reduced diameter extends into the reduced external diameter towards the other end to form a stopped bore. A plurality of radial spaced longitudinal slots parallel or spiral in the reduced external diameter. Spring members between the slots are deflected radially inwardly to grip the material when positioned with the bore of the material.A plurality of radially spaced holes are spaced in the external diameter, a driving means provides a coupling between the holder and the above described gripper.

The invention accordingly provides an internal gripping device to fit into the previously described holder suitable for internally gripping the bore of metal or composite bar material in automatic loaders or like machines which comprises a cylindrical gripper have an external diameter extending from one end and a reduced diameter extending from the other end.

The reduced diameter has a resessed diameter along its length, but leaving a conical spiget at the other end. A plurality of cylindrical compressive means is located within the recessed diameter. A sleeve slotted along its length to form segments and positioned around the cylindrical compressive means. A small recess is positioned at each end of the cylindrical body.

A spring means is located in the small recess to locate the segments of the cylindrical body. A plurality of radially spaced holes are spaced around the external diameter.

Embodiments of the feed device according to the present invention are not described with reference to the accompanying drawings in which Figure 1 Is a section along the longitudinal axis according to the first and second embodiments Figure 2 Is a section along the longitudinal axis according to the second embodiment Figure 3 Is a section along the longitudinal axis according to the third and fourth embodiment Figure 4 Is a section along the longitudinal axis according to the fourth embodiment Figure 5 Is a cross section along the longitudinal axis according to the fifth embodiment Figure 6 Is an end elevation showing the slots and segments Figure 7 Is an end elevation showing the slots and segments Figure 8 Is a cross section showing the slots and fingers.

Reference to Figure 1: A tube (1) with an internal thread (5) at one end has flats (6) positioned on the outside diameter.

The other end has a bore (7) and a reduced bore (8).

Reference to Figures 2 and 6: A removable external gripper comprises tube (1) with a large bore (10) extending from one end and a reduced bore (12) extending from the other.

A plurality of longitudinal slots separates the tube into segments (3) the reduced diameter (13) contains holes (9) into which pin (2) (Figure 1) is located. A compressive means (4) is positioned around the large diameter in to a recess to close the slots. With Figure 2 located within tube (1) of (figure 1) the material (14) is engaged within the bore (10) of segment (3) opening the slots (11) the compressive means is (4) is contained within the bore (7) applies a force to grip the material (14).

An alternative device provides a means of gripping tubular material within its bore.

Referring to Figures 3, 4, 5, 7 and 8, a tube (1) has a threaded bore (15) extending from one end. A reduced diameter (16) extends from the other end having a recess (16) and reduced diameter (17) in which compressive means (3) and {4) are located. A series of radially spaced pins (2) are located in the reduced diameter (26).

Referring to Figure 4: A tube having a bore (18) extending from one end and a reduced recessed diameter (19) a series of radially drilled holes (20) are located in the bore (18). A compressive means (7) is contained within the reduced recessed diameter (19) and a tube (6) has longitudinal slots (21) dividing the tube (6) into segments (36) and secured around the compressive means by (7) retainers (8) and (9) in operation the hollow bar stock (50) is pushed over the segmented tube (6) closing the slots (21) and compressing the compressive means (7) applying a grip to the bore of the bar stock (50) and allowing it to flex freely on the compressive means (3) and (4).

An alternative device provides a means for gripping tubular material within its bore.

Referring to Figure 5: A tube having a bore (28) extending from one end a reduced diameter (29) extending from the other end.

Radial holes are drilled in the bore (28) and a plurality of straight or spiral longitudinal slots (11) are in the reduced diameter (29) in operation the hollow bar stock (50) is located on the reduced diameter (29) closing the slots (11) and applying a grip by the fingers (12) to the bore of the material (50).

Claims to be filed later.

Claims

IMPROVEMENTS RELATING TO GRIPPER/COLLETS

CLAIMS I CLAIM FOR MY INVENTION 1. A device for gripping the end of Bar Stock to feed and retract it endwise, comprising a means to enclose the end of bar stock and yieldable means around the said means, to apply flexible compression around the bar end. A means connecting and locating the said means within the said device, a means on the said device to connect the said device to the machine member.
2. A device for gripping the end of hollow bar stock to feed and retract it endwise, comprising a means to engage within the bore of the hollow bar stock a yieldable compressible means to apply uniform pressure to the bore of the hollow bar stock, a flexible compressible means to position the said means on the said device, a means connecting and locating the said means to the said device.
3. A device according to claim 2 comprising a means to engage within the bore of the hollow bar stock, wherein the compressible means is provided by a plurality of radially spaced segments.
4. A device substantially as hereinbefore described with reference to the accompanying drawings.