US 5,129,656 AGrant
Racquet, in Particular a Tennis Racquet
Issue Date:1992-07-14
•16 Claims
•4 Drawing Sheets
Abstract
In a racquet, in particular, a tennis racquet, which incorporates a frame, an open or closed heart piece, and a shaft (2) that is joined to the heart piece, with the frame, heart piece and shaft being formed in one piece or connected releasably to each other, the grip (1) that is formed as a one-piece sleeve can be slid onto the shaft. The inside profile of the cross section of the grip (1) and the outside profile of the cross section of the shaft (2) incorporate longitudinal shape-locking and interacting supporting surfaces. The spacing between the supporting surfaces on the shaft (2) and the supporting surfaces of the grip (1) tapers in a wedge shape towards the unattached end (11) of the shaft (2). A removable distance piece (3) that prevents the grip (1) being slid axially into the mated position is releasably connected to the end (11) of the shaft. With the distance piece (3) installed on the shaft, the racquet can be tested with various grips (1). After removal of the distance piece (3) the grip is slid completely onto the shaft (2) and is then joined to the shaft so that, for all practical purposes, it cannot be released from the shaft.
Metadata
Assignee
- Head Sportgerate Gesellschaft m.b.H. & Co. OHG
Inventors
- Robert Marte
- Helmut Umlauft
Application Information
Application Number:US 7355114
Filing Date:1991-07-26
Priority Date:1990-07-31
Art Unit:334
Classifications
IPC:
A63B 4908
Field of Search:
27373 J;75;81 B;81 D;81 R;165;81.2
Patent Drawings (4 sheets)
Description
The present invention will be described in greater detail on the basis of the drawings appended hereto. These drawings show the following:
FIGS. 1, 2 and 3: the grip and the shaft in the mated position with the distance piece removed;
FIG. 1: a longitudinal section on the line I--I in FIG. 2;
FIG. 2: a cross section on the line II--II in FIG. 1;
FIG. 3: a cross section on the line III--III in FIG. 1;
FIG. 4: the end of the shaft and the end of the grip as in FIG. 1 in the position used for the trial with the distance piece being in position;
FIGS. 5 and 6: modified embodiments wherein the end of the grip and the end of the shaft are shown, on the left, in position with the distance piece acting as in a trial and, on the right, in the mated position with the distance piece removed.
In the position shown in FIGS. 1, 2 and 3, the grip 1 has been slid onto the shaft 2 all the way into the mated position, and the distance piece 3 (FIG. 4) has already been removed. The shaft 2 incorporates supporting surfaces 4, 5, 6, and the grip 1 incorporates supporting surfaces 7, 8, 9 which, in the mated position, fit snugly together, with a foil 10 interposed between them. On the one hand, such a foil 10 results in very close contact and provides a certain damping effect when the racquet strikes a ball. The spacing between the supporting surfaces 4, 5, 6 on the shaft 2 and the spacing between the supporting surfaces 7, 8, 9 on the shaft 1 is identically wedge-shaped to the whole length of the grip 1 and they taper equally towards the unattached end 11 of the shaft. The angle of this taper amounts to approximately 1.degree., and this ensures self-locking rigid seating.
On the grip 1, there are diametrically opposed lugs 12 that extend inwards, and which, in the fully installed mated position, snap into the transverse groove 13 on the shaft 2. The axial extent of the lugs 12 equals the axial extent or width, respectively, of the groove 13, so that when in the mated position the grip 1 is secured to the shaft 2 so as to be secured in both axial directions. Since the lugs 12 are not accessible when in the mated position shown in FIG. 1, the connection between shaft 2 and grip 1 is for all practical purposes unreleasable when in the mated position.
As is shown in FIG. 4, the distance piece 3 is connected to the unattached end 11 of the shaft through an interposed nominal break section 14. This nominal break point is formed by an annular groove and perforations 15. As long as this distance piece 3 is arranged on the end 11 of the shaft, the grip 1 can only be slid onto the shaft 2 as far as a position in which the distance piece 9 lies against the stop surface 16 of the grip 1. This is the case during a test, and this position is shown in the left-hand portion of FIG. 4. In this position, as is shown in the left-hand portion of FIG. 4, the lugs 12 cannot snap into the transverse groove 8 and thus the grip 1 can still be removed from the shaft 2 after the trial. The right-hand portion of FIG. 4 shows the position of the grip 1 on the shaft 2 before the distance piece 3 lies against the stop surface 12. This position, too, is possible prior to the trial and is even to be preferred, because in this position, which is shown in the right-hand portion of FIG. 4, it is easier to remove the grip 1 from the shaft 2. All that is important is that the distance piece 3 prevents the lugs 12 from snapping into the groove 13 for the last time as long as the grip 1 is not to be secured permanently in the mated position.
Only after a satisfactory trial is the distance piece 3 broken off from the end 11 of the shaft, which can be done very easily because of the nominal break section 14, whereupon the grip 1 is driven onto the shaft 2, into the mated position shown in FIG. 1, in which the grip 1 is installed securely on the shaft 2 so as to be unremovable for all practical purposes.
In the embodiment shown in FIG. 5, the unattached end piece 17 of the shaft 18 is of elastically deformable material and is secured to the shaft 18, for example, by adhesives. Two diametrically opposed lugs 19 are arranged on the end piece 17 and work in conjunction with an annual shoulder 20 in the grip 21. Because of the distance piece 22 that is installed on the end 17 of the shaft, and which works in conjunction with a stop surface 23 of the grip 21, in the trial position shown on the left, the lugs 19 are prevented from snapping into position behind the shoulder 20. After a successful test, the distance piece 22 is removed from the end 17 of the shaft, and the lugs 19 can snap behind the shoulder 20, into the mated position, as is shown on the right-hand side. Deformation of the shaft end 17 is made simpler because of a hollow chamber 24 in the end of the shaft. In this embodiment, between the shaft 18 or the end piece 17 itself, respectively, and the grip 21, there is an elastic intermediate layer 33, for example of rubber. This elastic intermediate layer is joined rigidly to the shaft 17, 18, for example, cemented in place, and provides a certain damping effect when the racquet strikes a ball.
FIG. 6 shows an embodiment in which, when in the mated position, the grip 25 is cemented to the shaft 2. Within the grip 25 there is a capsule or bag 27 that is filled with adhesive 26. A part 28 is rigidly connected to the end of the shaft 2 and this part incorporates a pointed pin or a cutter 29. Because of a distance piece 30 that is installed on the part 28, in the trial position that is shown on the left, the pin or the cutter 29 is prevented from cutting or puncturing the bag of adhesive 27. After removal of the distance piece 30, the pin or blade 29 can cut or puncture the bag or capsule 27, as is shown on the right, whereupon the adhesive 26 can escape and penetrate the gap 31 between the shaft and the grip.
In this embodiment, in the mated position, adhesive must enter the gap 31 although, in the trial position shown on the left, the grip 25 must be so firmly installed that the racquet can be tested. For this reason, the shaft 2 incorporates longitudinal ribs 32. Because of these longitudinal ribs 32 the grip 25 is guided on the shaft 2 during the trial and is held sufficiently firmly for the test, whereas in the mated position, the adhesive can flow into the gap 31 between these ribs.
Claims
We claim:
1. A racquet comprising a frame; and open or closed heart piece; the frame, heart piece and shaft being manufactured as one piece or being connected to each other so as to be fixed; and a grip that is formed as a one-piece sleeve that can be slid onto the shaft and secured thereon when in the fully installed mated position, the inside profile of the cross section of the grip and the outside profile of the cross section of the shaft incorporating supporting surfaces that are a shape-locking fit with each other and extend longitudinally over at least part of the length of the shaft, by means of which the grip is secured on the shaft in such a manner that it cannot rotate independently of said shaft, and wherein, on the one hand, the supporting surfaces of the shaft and, on the other hand, the supporting surfaces of the grip converge in a wedge shape at least over a part of the length of the grip in the direction of the unattached end of the shaft and the supporting surfaces of the grip are parallel to the wedge surfaces of the shaft that work in conjunction with them; and wherein between the shaft and the grip there is a distance piece which is removable and which limits the axial installation movement of the grip and complete installation of the grip in the mated position.
2. A racquet as defined in claim 1, wherein the distance piece is connected to the shaft or the grip so as to be releasable.
3. A racquet as defined in claim 1, wherein the distance piece is releasably connected to the unattached end of the shaft and is supportable against a stop surface of the grip.
4. A racquet as defined in claim 1, wherein the distance piece (3) is connected to the unattached end of the shaft (2) through a nominal break cross section (14).
5. A racquet as defined in claim 1 wherein the distance piece is set onto the unattached end of the shaft or is plugged into the unattached end of the shaft.
6. A racquet as defined in claim 1 wherein the grip is connectable to the shaft so as to be unreleasable or releasable only with difficulty only after removal of the distance piece, by way of means for securing the grip and shaft together.
7. A racquet as defined in claim 1 wherein two, diametrically opposed lugs are formed on the inside surface of the grip and at least one groove is formed transversely to the axis on the shaft the grip consisting of elastically deformable material.
8. A racquet as defined in claim 7, wherein the lug and the groove are defined axially by defining surfaces that are transverse to the axis of the shaft and the spacing of the defining surfaces of the lug corresponding to the spacing of the defining surfaces of the groove.
9. A racquet as defined in claim 1, wherein the unattached end of the shaft is hollow, consists of elastically deformable material, and incorporates two, diametrically opposed lugs that snap into position behind a step that is formed on the inside surface of the grip.
10. A racquet as defined in claim 1, wherein within the grip there is a capsule or a bag that contains a quantity of adhesive and after removal of the distance piece when the grip is slid on into the mated position, this is destroyed by a blade or a pointed pin that is arranged on the end of the shaft.
11. A racquet as defined in claim 1, wherein the angle of taper that is subtended between the supporting surfaces is self-locking.
12. A racquet as defined in claim 1, wherein the angle of taper subtended between the supporting surfaces is at most 3.degree..
13. A racquet as defined in claim 1, the distance piece is so dimensioned that the installation path of the grip as far as the stop on the distance piece is at least 98%, of the total installation path into the mated position when the distance piece has been removed.
14. A racquet as recited in claim 13, wherein the distance piece is so dimensioned that the installation path of the grip as far as the stop on the distance piece is 99%.
15. A racquet as defined in claim 1, wherein the shaft and the hollow space within the space are of elliptical or octagonal cross section.
16. A racquet as recited in claim 1, wherein the angle of taper subtended between supporting surfaces is approximately 1.degree..