US20070027007A1

US20070027007A1 - Weight assembly and method of manufacture

Info

Publication number: US20070027007A1
Application number: US11/191,790
Authority: US
Inventors: Scott Frasco
Original assignee: Iron Grip Barbell Co Inc
Current assignee: Iron Grip Barbell Co Inc
Priority date: 2005-07-27
Filing date: 2005-07-27
Publication date: 2007-02-01

Abstract

A weight assembly is provided having a handle securely attached to first and second weight heads. More particularly, each weight head includes a side wall and an end wall that together define the bore for receiving an end of the handle via press-fit. The side wall includes an outer portion disposed at an angle relative to a longitudinal axis of the bore and an intermediate portion disposed between the outer portion and the end wall. The end portions of the handle have a diameter that is greater than that of the gripping portion of the handle. The bore and the handle ends are cooperatively sized to enable a secure press-fit. First and second weld seams are disposed about the handle in contact with the corresponding outer portion of the side wall of each weight head. More particularly, the weld seams are substantially confined to a recess defined between the corresponding outer portion of the side wall of each weight head and the corresponding end portion of the handle. Moreover, the upper portion of each weight head is configured to facilitate a secure weld between the weight head and the handle, while minimizing damage to the components to include heat-affected zones on the handle.

Description

BACKGROUND OF THE INVENTION

The present invention relates generally to weight assemblies such as dumbbells and barbells and, more particularly, to such weight assemblies having a handle welded to two heads of fixed weight.
In weightlifting, weight assemblies of various configurations are commonly used. For example, dumbbells and barbells both include an elongated handle extending between two weights. In dumbbells, the handle is sized to accommodate one hand, whereas, in barbells, the handle is sized to accommodate both hands, spaced apart from each other.
Of the various configurations of weight assemblies, dumbbells and barbells are two of the most common and versatile. As such, they are typically in high demand at weightlifting facilities. Thus, it is common for such facilities to provide a number of dumbbells and barbells configured at different weights, e.g., ranging from five pounds to 200 pounds. To that end, sets of barbells and sets of dumbbells are available in which each weight assembly is fixed at a prescribed weight. Such weight assemblies typically include an elongated handle permanently attached to weight heads, providing a preset weight.
Various approaches have been used to attach the handle to weight heads in such weight assemblies. In one approach, as depicted in FIG. 1, the handle 10 is disposed in cylindrical cavities defined by inwardly facing surfaces 12 of each weight head 14. A fillet-type weld 16 is provided around the handle, securing the handle to each weight head. Although generally effective, shortfalls exist. For example, during welding, heat is directed towards the handle about the junction of the head and the handle. This heating can discolor the metal and create a heat-affected zone 18 on the handle. Such heat-affected zones can substantially diminish the strength of the handle. Over time, cracks can occur in the handle. These cracks can exacerbate after extended use, which can result in total failure of the connection between the handle and the weight.
It should, therefore, be appreciated that there remains a need for a weight assembly having a handle attached to weight heads in a secure and durable manner. The present invention fulfills this need and others.

SUMMARY OF THE INVENTION

The invention resides in a weight assembly having a handle securely attached to first and second weight heads. More particularly, each weight head includes a side wall and an end wall that together define a bore for receiving an end of the handle via press-fit. The side wall includes an outer portion disposed at an angle relative to a longitudinal axis of the bore and an intermediate portion disposed between the outer portion and the end wall. First and second weld seams are disposed about the handle in contact with the corresponding outer portion of the side wall of each weight head such that the weld is spaced apart from the gripping portion of the handle. The end portions of the handle have a diameter that is greater than that of the gripping portion of the handle. The bore and the handle ends are cooperatively sized to enable a secure press-fit. Moreover, the upper portion of each weight head is configured to facilitate a secure weld between the weight head and the handle, while minimizing damage to the components to include heat-affected zones on the handle.
In a detailed aspect of exemplary embodiments, the outer portion is sufficiently sized to receive the weld seam between the head and the handle. For example, the outer portion can have a prescribed curvature, as viewed in cross-section. In another example, the outer portion has a frusto-conical configuration. More particularly, each weld seam can be generally confined in a recess defined between the corresponding outer portion and the corresponding end portion of the handle. The weight heads can be covered with a compliant material.
In another example, the outer portion can have a notch configuration, in which a first surface, adjacent to the intermediate portion is angled outwardly relative to the longitudinal axis of the bore and a second surface extends towards the opening of the bore generally parallel to the longitudinal axis of the bore.
The invention also resides in a method of manufacturing a weight assembly, comprising:

providing first and second weight heads, each weight head having a side wall and an end wall that together define a bore having a prescribed diameter, the side wall including
- an outer portion disposed about an opening to the bore and at an angle relative to a longitudinal axis of the bore, and
- an intermediate portion disposed between the outer portion and the end wall;
providing an elongated handle having first and second end portions and a gripping portion between the end portions each end portion having a diameter greater than a diameter of the gripping portion;
pressing the first end portion of the handle into the bore of the first weight head;
pressing the second end portion of the handle into the bore of the second weight head;
welding the handle to the first weight head such that the resulting weld seam is substantially confined to a recess defined between the outer portion of the side wall of the first weight head and the corresponding end portion of the handle and such that the weld seam is spaced apart from the gripping portion of the handle; and

welding the handle to the second weight head such that the resulting weld seam is substantially confined to a recess defined between the outer portion of the side wall of the second weight head and the corresponding end portion of the handle and such that the weld seam is spaced apart from the gripping portion of the handle.
In an exemplary aspect of the method, the step of providing a handle can include providing a metal bar of a first diameter, machining an intermediate region of the bar to a second diameter, less than the first diameter, thereby defining the gripping portion, and machining a transition region between the gripping portion and each end portion.
In another exemplary aspect of the method, the step of providing first and second weight heads can include providing a first and second head blank, creating a cylindrical hole of a prescribed depth in each head blank, less than a thickness of the head blank, thereby forming the intermediate portion of the side wall, and removing material about the outer edge of the cylindrical hole, thereby forming the outer portion of the side wall.
For purposes of summarizing the invention and distinguishing it over the prior art, certain advantages of the invention have been described herein. Of course, it is to be understood that not necessarily all such advantages may be achieved in accordance with any particular embodiment of the invention. Thus, for example, those skilled in the art will recognize that the invention may be embodied or carried out in a manner that achieves or optimizes one advantage on group of advantages as taught herein without necessarily achieving other advantages as may be taught or suggested herein.
All of these embodiments are intended to be within the scope of the invention herein disclosed. These and other embodiments of the present invention will become readily apparent to those skilled in the art from the following detailed description of the preferred embodiments having reference to the attached figures, the invention not being limited to any particular preferred embodiment disclosed.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of the present invention will now be described, by way of example only, with reference to the following drawings in which:
FIG. 1 is a cross-sectional view of a first end of a prior art weight assembly.
FIG. 2 is an elevational view of a first embodiment of a weight assembly in accordance with the invention, depicting a two weight heads and a handle, the weight heads coated with a compliant material.
FIG. 3 is a longitudinal cross-sectional view of the weight head of the weight assembly of FIG. 2.
FIG. 4 is a cross-sectional view, taken along line 4-4 of FIG. 2, of the first end of the weight assembly, excluding the coating of compliant material and depicted a weld seam spaced from a gripping portion of the handle.
FIG. 5 is a longitudinal cross-sectional view of the weight assembly depicted in FIG. 2
FIG. 6 is a longitudinal cross-sectional view, similar to FIG. 5, of a first end of a second embodiment of a weight assembly in accordance with the invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

With reference now to the drawings, and particularly to FIGS. 2 to 5, there is shown a dumbbell 20 having two fixed-weight heads 22 and a handle 24 axially extending between the heads. Each weight head defines a bore 26 (FIG. 3) for receiving a corresponding end 28 (FIG. 5) of the handle. More particularly, each bore is defined by a side wall 30 and an end wall 32, providing an open end and a closed end. The side wall includes an outer portion 34 disposed about the bore opening and the intermediate portion 36 disposed between the outer portion and the end wall. The bore and the handle end are cooperatively sized to enable a secure press-fit. Moreover, the upper portion of each weight head is configured to facilitate a secure weld between the weight head and the handle, while minimizing damage to the components to include heat-affected zones on the handle.
As shown in FIG. 2, the handle 24 includes a gripping portion 38 sized to receive a single hand, in normal use. Also, other embodiments of weight assemblies are contemplated having a comparatively longer gripping portion (e.g., barbells).
With reference to FIGS. 3 to 5, the outer portion 34 of each side wall 30 is beveled with a prescribed curvature, as viewed in cross-section. With the handle end 28 disposed in the bore, the outer portion and the handle together define a recess, facilitating welding of the components. More particularly, the outer portion is configured such that a weld seam 40 can be disposed in the recess. Moreover, the configuration of the outer portion minimizes exposure of the handle during welding, thereby inhibiting heat-affected zones on the handle.
In the exemplary embodiments, the handle ends are substantially received within the bore, leaving the narrower gripping portion extending from the weight heads. In other embodiments, a portion of the handle end can extend beyond the opening of the bore, so long as adequate room is provided for receiving the weld seam, between the upper portion of the bore and the handle end. Also, in other embodiments, the outer portion can be provided with various other shapes, so long as sufficient space is provided for receiving a weld. For example, the outer portion can have a notch configuration, in which a first surface, adjacent to the intermediate portion is angled outwardly relative to the longitudinal axis of the bore and a second surface extends towards the opening of the bore generally parallel to the longitudinal axis of the bore.
The dumbbell 20 includes a compliant material 44, e.g., rubber or urethane, coating the weight heads. In the exemplary embodiment, the compliant material covers the weld seam, hiding it from view. Other embodiments, the weight heads can exclude a complaint material entirely.
The handle 24 is formed of a metal bar having a constant diameter. In the exemplary embodiment, a steel bar is used. The gripping portion 38 is formed by machining an intermediate region of the bar to a second diameter. A transition region 42 between the gripping portion and each end portion 28 is also machined, forming the handle. In the exemplary embodiments, the gripping portion has a textured surface and a constant diameter. In other embodiments, various configurations for the gripping portion can be used as desired. In addition, in other embodiments, the handle can be sized for use with various other weight assemblies, e.g., barbells, as desired.
The weight heads 22 and the handle 24 are cooperatively sized to achieve a secure attachment, considering the anticipated forces endured. Preferably, the depth of the bore is greater than or equal to the diameter of the corresponding end portion of the handle. Each handle end is positioned in secure contact with the end wall and the side wall.
In an exemplary method of manufacturing, a machine press, e.g., a hydraulic press, is used. For each weight head, the machine press drives the end portion of the handle into the bore under considerable force. Having a secure press-fit facilitates an effective distribution of force about the dumbbell. Prior to installation, the diameter of the end portions is oversized relative to the diameter of the bore.
For each weight head 22, the machine press drives the end portion 32 into the bore 26 into contact with the end wall 32. Sufficient force is used to drive the end portion into contact with the end wall of the bore. The operation is performed sequentially, one handle end at a time. Alternatively, the handle ends could both be driven into position simultaneously without departing from the invention.
Once the handle end is position in the bore of the corresponding weight head, the weld seam 40 is provided about the handle. The weld seam is formed of a filler material selected to provide secure attachment between the materials of the handle and weight head and is heated to a prescribed temperature. In forming the weld, heat can be directed towards the outer portion, away from the handle, minimizing any heat-affected zone on the handle. In other embodiments, a weld seam can be formed using various other welding approaches, as needs dictate. Thereafter, the compliant material 44 is applied. Alternatively, portions of the compliant material can be applied earlier in the process.
FIG. 6 depicts a second embodiment, weight assembly 60, in which an outer portion 62 of a bore has a frusto-conical configuration on each weight head 64. The outer portion is sized to receive a weld seam 66 with in a recess defined between the outer portion and the handle 68.
It should be appreciated from the foregoing that the present invention provides a weight assembly having a handle securely attached to first and second weight heads. More particularly, each weight head includes a side wall and an end wall that together define the bore for receiving an end of the handle. The end portions of the handle have a diameter that is greater than that of the gripping portion of the handle. The bore of each weight head and the handle ends are cooperatively sized to enable a secure press-fit. The side wall includes an outer portion disposed at an angle relative to a longitudinal axis of the bore and an intermediate portion disposed between the outer portion and the end wall. First and second weld seams are disposed about the handle in contact with the corresponding outer portion of the side wall of each weight head. More particularly, the weld seams are substantially confined to a recess defined between the corresponding outer portion of the side wall of each weight head and the corresponding end portion of the handle. Moreover, the upper portion of each weight head is configured to facilitate a secure weld between the weight head and the handle, while minimizing damage to the components to include heat-affected zones on the handle.
Although the invention has been disclosed in detail with reference only to the exemplary embodiments, those skilled in the art will appreciate that various other embodiments can be provided without departing from the scope of the invention. Accordingly, the invention is defined only by the claims set forth below.

Claims

1. A weight assembly, comprising:

first and second weight heads spaced apart from each other, each weight head having a side wall and an end wall that together define a bore having a longitudinal axis, the side wall including

portion disposed about an opening to the bore and at an angle relative to the longitudinal axis of the bore, and

an intermediate portion disposed between the outer portion and the end wall;

an elongated handle having two end portions and a gripping portion between the end portions, each end portion having a diameter greater than a diameter of the gripping portion, each end portion press-fit into a corresponding bore of the first and second weight heads such that the handle extends between the first and second weight heads; and

first and second weld seams each substantially confined to a recess defined between the corresponding outer portion of the side wall of each weight head and the corresponding end portion of the handle such that the weld seams are spaced apart from the gripping portion of the handle.

2. A weight assembly as defined in claim 1, wherein the outer portion of each side wall has a prescribed curvature, as viewed in cross-section.

3. A weight assembly as defined in claim 1, wherein each bore has a depth greater than or equal to the diameter of the corresponding end portion of the handle.

4. A weight assembly as defined in claim 1, wherein the outer portion has a frusto-conical configuration.

5. A weight assembly as defined in claim 1, wherein the outer portion has a notch configuration, the outer portion including

a first surface, adjacent to the intermediate portion, angled outwardly relative to the longitudinal axis of the bore, and

a second surface extending from the first surface, generally parallel to the longitudinal axis of the bore.

6. A weight assembly as defined in claim 1, wherein a coating of compliant material is provided over the first and second weight heads, substantially covering the first and second weld seams.

7. A method of manufacturing a weight assembly, comprising:

providing first and second weight heads, each weight head having a side wall and an end wall that together define a bore having a prescribed diameter, the side wall including

an outer portion disposed about an opening to the bore and at an angle relative to a longitudinal axis of the bore, and

an intermediate portion disposed between the outer portion and the end wall;

providing an elongated handle having first and second end portions and a gripping portion between the end portions each end portion having a diameter greater than a diameter of the gripping portion;

pressing the first end portion of the handle into the bore of the first weight head;

pressing the second end portion of the handle into the bore of the second weight head;

welding the handle to the first weight head such that the resulting weld seam is substantially confined to a recess defined between the outer portion of the side wall of the first weight head and the corresponding end portion of the handle and such that the weld seam is spaced apart from the gripping portion of the handle; and

welding the handle to the second weight head such that the resulting weld seam is substantially confined to a recess defined between the outer portion of the side wall of the second weight head and the corresponding end portion of the handle and such that the weld seam is spaced apart from the gripping portion of the handle.

8. A method as defined in claim 7, wherein the outer portion of each side wall has a prescribed curvature, as viewed in cross-section.

9. A method as defined in claim 7, wherein the outer portion of each side wall has a notch configuration, the outer portion including

10. A method as defined in claim 7, wherein the weight heads are covered with a compliant material.

11. A method as defined in claim 7, wherein each bore has a depth greater than or equal to the diameter of the corresponding end portion of the handle.

12. A method as defined in claim 7, wherein the step of providing a handle includes,

providing a metal bar of a first diameter,

machining an intermediate region of the bar to a second diameter, less than the first diameter, thereby defining the gripping portion, and

machining a transition region between the gripping portion and each end portion.

13. A method as defined in claim 7, wherein the step of providing first and second weight heads includes,

providing a first head blank and a second head blank,

creating a cylindrical hole of a prescribed depth in each head blank, less than a thickness of the head blank, thereby forming the intermediate portion of the side wall and the end wall, and

removing material about the outer edge of the cylindrical hole, thereby forming the outer portion of the side wall.