GB2264064A

GB2264064A - Wrist and forearm exercise apparatus

Info

Publication number: GB2264064A
Application number: GB9202632A
Authority: GB
Inventors: Ping Chen
Original assignee: Individual
Current assignee: Individual
Priority date: 1992-02-07
Filing date: 1992-02-07
Publication date: 1993-08-18
Anticipated expiration: 2012-02-07
Also published as: GB9202632D0; FR2698793B3; FR2698793A3; GB2264064B

Abstract

The apparatus includes a coiled compression spring (33) which offers an adjustable resistance to the movement of the wrist. A spring pressing member (34) is movable by actuation of the rotary knob (35), to vary the compression of the compression spring (33). A grip assembly (20) is mounted pivotally on a forearm rest unit (10) and includes two parallel arms (23), and a grip piece (22) attached to the arms (23) by two lock bolts (24). Each of the arms (23) of the grip assembly (20) has a row of sequential and intercommunicated circular holes (231) so that the end portions of the grip piece (22) can be selectively positioned within selected two of the circular holes (231) which may be in or out of alignment. <IMAGE>

Description

Title: WRIST AND FOREARM EXERCISE APPARATUS This invention relates to a wrist and forearm apparatus, more particularly to a safety apparatus for strengthening the users wrist 'and forearm which is easy to adjust and use.

The improvement of this invention is directed to U.S. Pat. No. 4,589,655 of David Ammon which teaches a wrist and forearm exercise apparatus, including an extension spring for applying a resistance to the pivotal movement of a grip piece. Referring to Fig. 1, the extension spring 66 has two bent end portions (a) on which stress is concentrated. As a result, after the apparatus is used for a long time, the extension spring 66 easily breaks at the portions (a) when in use, thereby throwing an end plug 74 (see Fig. 2) and possibly hurting the user by throwing the object toward his eye, etc. Accordingly, it is necessary to take precautions to prevent such a mishap. This apparatus further includes two parallel rows of spaced holes formed in the arms of a grip assembly.The grip piece can be selectively engaged with two aligned holes of the grip assembly by removing two bolts, so as to vary the position of the grip piece on the apparatus according to the length of the forearm of the user, thereby enabling the user to hold the grip piece. It is time-consuming to adjust the grip piece of the apparatus in this manner.

We have now found it possible to provide a safety apparatus for strengthening wrist and forearm.

We have also found it possible to provide a wrist and forearm exercise apparatus wherein the position of the grip piece is easy to adjust.

According to this invention, a wrist and forearm exercise apparatus includes an annular forearm rest unit which is shaped so as to permit a forearm of a user to extend therethrough. The forearm rest unit includes a front arcuate plate and a rear arcuate plate having a front end portion connected securely to the rear end portion of the front arcuate plate. The front and rear arcuate plates extend in opposite directions from the juncture thereof. When the apparatus is used, the front portion of the forearm engages the front arcuate plate proximate the wrist. The rear end of the rear arcuate plate engages the forearm proximate its juncture with the upper arm. A grip assembly has a front end portion with a grip piece secured thereto, and a rear end portion connected pivotally to the forearm rest unit.A biasing mechanism biases the grip assembly to locate at a predetermined position on the forearm rest unit and includes a coiled compression spring having a front end retained on the front arcuate plate and a rear end. An anchoring member is retained on the rear end of the compression spring. A cable extends through the compression spring and is fastened to the anchoring member at one end thereof and to the grip assembly at the other end of the cable. A resistance adjustment device includes a movable spring pressing. member on which the front end of the compression spring abuts, and a rotary knob connected operatively to the spring pressing member and rotatable to move the spring pressing member toward or away from the anchoring member, so as to press the compression spring against the anchoring member.The compression spring thus solves the problem of stress concentration of a conventional apparatus.

The grip assembly includes a U-shaped body having two parallel arms and a connecting portion interconnecting the arms. Each of the arms has a row of sequential and intercommunicated circular holes formed therethrough. Each of the circular holes has two enlarged and curved end portions. The grip piece is an elongated rod having two curved end portions each of which has a threaded hole formed in an end surface thereof and is well-matched with one of the circular holes of one of the arms. The grip assembly further includes two lock bolts each of which extends through one of the circular holes to engage within one of the threaded holes of the grip piece. Each of the lock bolts has a head and an externally threaded shank.

Each of the shanks of the lock bolts has a curved and enlarged portion which is well-matched with one of the circular holes in the arms of the grip assembly. The two curved end portions of the grip piece can be positioned within selected two of'the circular holes in the arms in accordance with the length of the forearm of the user by somewhat loosening the lock bolts from the grip piece.

Other features and advantages of this invention will become apparent in the following detailed description of the preferred embodiments of this invention, with reference to the accompanying drawings, in which: Figs. 1 and 2 are schematic views showing the extension spring of a conventional wrist and forearm exercise apparatus; Fig. 3 is an exploded perspective view showing a wrist and forearm exercise apparatus of this invention; Fig. 3A is an exploded sectional view illustrating the assembly of the cable and the retainer of the wrist and forearm exercise apparatus according to this invention; Fig. 4 is a sectional view showing the resistance adjustment device of the wrist and forearm exercise apparatus according to this invention, wherein the compression spring is in a normal position;; Fig. 5 is a sectional view showing the resistance adjustment device of the wrist and forearm exercise apparatus according to this invention, wherein the compression spring is compressed; Fig. 6 is a sectional view showing another resistance adjustment device of the wrist and forearm exercise apparatus according to this invention; Figs. 7A and 7B are schematic views illustrating the use of the wrist and forearm exercise apparatus according to this invention; Figs. 8A and 8B are schematic views illustrating the adjustment to the grip piece of the wrist and forearm exercise apparatus; and Fig. 9 is a sectional view illustrating how to mount the grip piece on the wrist and forearm exercise apparatus in accordance with this invention.

Referring to Fig. 3, a wrist and forearm exercise apparatus of this invention includes an annular forearm rest unit 10, a grip assembly 20, a biasing mechanism 30, a resistance adjustment device and a counter 40.

The forearm rest unit 10 includes a front arcuate plate 11 and a rear arcuate plate 12. The front end portion of the rear arcuate plate 12 is integrally formed with the rear end portion of the front arcuate plate 11. As best shown in Figs. 7A and 7B, the front arcuate plate 11 and the rear arcuate plate 12 extend in opposite directions from the juncture thereof. Two aligned devises 111 are provided on two sides of the front arcuate plate 11, so that the grip assembly 20 is mounted pivotally thereon. A first mounting block 13 attaches a knob mounting tube 14 to the front arcuate plate 11. The knob mounting tube 14 has a central bore 141 formed therethrough. Two guiding rails 142 project from the inner surface of -the knob mounting tube 14.

The front end surface 143 of the knob mounting tube 14 has a hole 144 formed therethrough. The front arcuate plate 11 further has two mounting holes 112 formed therethrough behind the first mounting block 13, so as to screw a second mounting block 15 thereto. The second mounting block 15 attaches a spring accommodating tube 16 to the front arcuate plate 11, in such a manner that the spring accommodating tube 16 is aligned with the knob mounting tube 14 in a coaxial relationship. The spring accommodating tube 16 has a central bore 161 formed therethrough, an open front end and a closed rear end 162. The spring accommodating tube 16 is spaced apart from the knob mounting tube 14 at a distance (h), as shown in Fig. 4. The spring 'accommodating tube 16 has a guiding slot 163 formed through the front end portion thereof. The guiding slot 163 has an open end at the front end of the spring accommodating tube 16. The spring accommodating tube 16 is provided with a series of markings 164 near the guiding slot 163 which represent spring pressure values. An annular sponge material 17 is attached to the inner surfaces of the front arcuate plate 11 and the rear arcuate plate 12, so as to protect the forearm of the user, which extends through the forearm rest unit, when the apparatus is used. As best shown in Figs. 7A and 7B, when this apparatus is in use, the front portion of the forearm engages the front arcuate plate 11 proximate the wrist. The rear end of the rear arcuate plate 12 engages the forearm proximate its juncture with the upper arm.

The grip assembly 20 includes a U-shaped body 21 and a grip piece 22 which is in the form of an elongated rod. The U-shaped body 21 has two parallel arms 23 which are interconnected by a connecting portion 211. Each of the arms 23 has a pivot portion 212 connected to one of the devises 111, and a row of sequential and intercommunicated circular holes 231 formed through the arm 23. As best shown in Fig. 9, each of the circular holes 231 has two curved end portions 232; the inner one well-matched with a curved end portion 221 of the grip piece 22, and the outer one well-matched with the curved and enlarged portion 241 of the shank of a lock bolt 24. The grip piece 22 has two threaded holes (22a) formed in the end surfaces thereof.The lock bolts 24 are passed through selected two of the circular holes 231 of the arms 23 of the body 21 to engage within the threaded holes (22a) of the grip piece 22. Accordingly, by somewhat loosening the lock bolts 24 from the grip piece 22, the grip piece 22 can be moved to engage the curved end portions (22a) within selected two of the circular holes 231 in the arms 23 in accordance with the length of the forearm of the user. Thus, ' the user can grip comfortably the grip piece 22. The selected two circular holes 231 may be out of alignment, as shown in Fig. 7B so as to increase the comfort in gripping the grip piece 22.

The biasing mechanism 30 includes an anchoring member 31, a cable 32 and a coiled compression spring 33 which is disposed within the spring accommodating tube 30. The anchoring member 33 has a counterbore 311 formed therethrough which has an enlarged end portion 312. The cable 32 extends through the anchoring member 33, the compression spring 33 and the cable hole in the connecting portion 211 of the body 21 of the grip assembly 20 to couple with a plastic retainer 50 of circular cross-section. As best shown in Fig. 3A, after the cable 32 has been passed through the cable hole of the connecting portion 211, an increaseddiameter cable portion 321 is attached to the cable 32 and is passed through a metal retaining ring 51 and into the enlarged portion 502 of the retaining groove 501 of the retainer 50.Then, the retaining ring 51 is sleeved on the small-diameter portion of the retainer 50, so as to prevent removal of the enlarged cable portion 321 from the retainer 50. As illustrated, the retainer 50 has a small-diameter portion and a largediameter portion in which the enlarged portion 502 of the retaining groove 501 is formed The retaining groove 501 is formed in the end surface of the smalldiameter portion of the retainer 50 and divides -the same into two halves, which can be pulled away from each other to permit the increased-diameter cable portion 321 to move into the enlarge portion 502 of the retaining groove 501. This is due to the fact that the retainer 50 is made of a flexible plastic and that the retaining groove 501 has two open ends on the opposite sides of the retainer 50.

To retain the compression spring 33 on the cable 32, the cable 32 has an enlarged end 321 which is received within the enlarged end portion 312 of the counterbore 311. The rear end portion of the compression spring 33 is sleeved on the small-diameter portion of the anchoring member 31 and is blocked by the large-diameter portion of the anchoring member 31.

In a case where the grip assembly 20 is rotated relative to the forearm rest unit 10, when the user lets go of the grip piece 22, the biasing mechanism returns the grip assembly 20 to its original position.

Referring to Figs. 4 and 5, in this embodiment, the resistance adjustment device includes a movable spring pressing member or externally threaded rod 34 which extends into the front end of the spring accommodating tube 16 at one end thereof and into the rear end of the knob mounting tube 14. The externally threaded rod 34 includes a pressing rear end portion 36 from which a guide block 361 projects into the guide slot 163 of the spring accommodating tube 16, and two opposed guiding slots 341 formed in the two opposite sides of the rod 34. The guiding slots 341 engage with the guiding rails 142 of the knob mounting tube 14.

Accordingly, the externally threaded rod 34 can move axially, but cannot rotate in the spring accommodating tube 16 and the knob mounting tube 14. A tubular rotary knob 35 has an internally threaded portion 351 engaged with the externally threaded rod 34, a front end sleeved on the rear end of the knob mounting tube 14, and a rear end sleeved on the front end of the spring accommodating tube 16. When the rotary knob 35 is rotated, the externally threaded rod 34 moves toward or away from the rear end of the spring accommodating tube 16 to press the compression spring 33 against the anchoring member 31, so as to adjust the spring pressure, thereby varying the resistance to the pivotal movement of the grip assembly 20 relative to the forearm rest unit 10.

Referring to Fig. 6, another embodiment of the resistance adjustment device is shown. In this embodiment, like the first embodiment, a knob mounting tube 14 is connected securely to a first mounting block (13a), and a spring accommodating tube (16a) is connected securely to a second mounting block (15a) so as to receive a compression spring (33a) therein.

Unlike the first embodiment, a guiding slot (142a) is formed in the rear end portion of the knob mounting tube (14a) and has an open end at the rear end of the knob mounting tube (14a), but not formed in the spring accommodating tube (16a). The front end of the spring accommodating tube (16a) is press fitted in the rear end of the knob mounting tube (14a). In this embodiment, the spring pressing member is an internally threaded tubular element (34a) which is accommodated within said rear end portion of the knob mounting tube (14a). The tubular element (34a) has a guiding block (341a) projecting therefrom into the guiding slot (142a) of the knob mounting tube (14a), so that the tubular element (34a) can move axially, but cannot rotate in the knob mounting tube (14a). The knob mounting tube (14a) has an externally threaded front end portion which is engaged with an internally threaded ring (36a). The ring (36a) has an inward flange (361a) projecting radially inwardly therefrom which is spaced apart from the front end of the knob mounting tube (14a) at a predetermined distance. A rotary knob is generally shaped in the form of a bolt (352a) which has an externally threaded shank (351a), a head with an outward flange (352a) projecting radially outwardly therefrom, and a central bore through which a cable (32a) extends. The outward flange (352a) is confined between the inward flange (361a) of the ring (36a) and the front end of the kndb mounting tube (14a) in such a manner that the head of the bolt (35a) can be rotated by hand.Because the externally threaded shank (351a) is engaged within the internally threaded ring (34a), when the head of the bolt (35a) is rotated manually, the ring (34a) moves toward or away from the rear end of the spring accommodating tube (16a) to press the compression spring (33a) against an anchoring member (31a).

Again referring to Fig. 3, the counter 40 is installed on the first mounting block 13, so as to detect and indicate the number of the pivotal movement of the grip assembly 20.

The wrist and forearm exercise apparatus can be operated in two manners. First, as shown in Fig. 7A, the rear arcuate plate 12 is positioned below the front arcuate plate 11. In this manner, the grip assembly 20 can be turned downward. Second, as shown in Fig. 7B., the apparatus is inverted. That is to say, the front arcuate plate 11 is positioned below the rear arcuate plate 12. In this situation the grip assembly 20 can be turned upward. Consequently, the exercise effect of the wrist and forearm exercise apparatus is increased.

Claims

CLAIMS:

1. A wrist and forearm exercise apparatus comprising: an annular forearm rest unit, shaped so as to permit a forearm of a user to ' extend therethrough, including a front arcuate plate and a rear arcuate plate having a front end portion connected securely to the rear end portion of.said front arcuate plate, said front and rear arcuate plates extending in the opposite directions from a juncture thereof, the front portion of said forearm engaging said front arcuate plate proximate the wrist, the rear end of said rear arcuate plate engaging said forearm proximate its juncture with the upper arm; a grip assembly having a front end portion with a grip piece secured thereto, and a rear end portion connected pivotally to said forearm rest unit;; a biasing mechanism biasing said grip assembly to locate at a predetermined position relative to said forearm rest unit and including a coiled compression spring having a front end retained on said front arcuate plate and a rear end, an anchoring member retained on said rear end of said compression spring, and a cable extending through said compression spring and fastened to said anchoring member at one end thereof and to said grip assembly at the other end of said cable; and a resistance adjustment device including a movable spring pressing member on which said front end of said compression spring abuts, and a rotary knob connected operatively to said spring pressing member and rotatable to move said spring pressing member toward or away from said anchoring member, so as to press said spring pressing member against said anchoring member.

2. A wrist and forearm exercise apparatus as claimed in Claim 1, wherein said grip assembly includes a U-shaped body having two parallel arms and a donnecting portion interconnecting said arms, each of said arms having a row of sequential and intercommunicated circular holes formed therethrough, each of said circular holes having two curved end portions, said grip piece being an elongated rod having two curved end portions each of which has a threaded hole formed in an end surface thereof and is well-matched with one of said circular holes of one of said arms, said grip assembly further including two lock bolts each of which extends through one of said circular holes to engage within one of said threaded holes of said grip piece, each of said lock bolts having a head and an externally threaded shank, each of said shanks of said lock bolts having a curved and enlarged portion which is well-matched with one of said circular holes in said arms of said grip assembly, whereby, said two curved end portions of said grip piece can be moved to engage within selected two of said circular holes in said arms in accordance with the length of the forearm of the user by somewhat loosening said lock bolts from said grip piece.

3. A wrist and forearm exercise apparatus as claimed in Claim 2, wherein said connecting portion of said grip assembly has a cable hole formed therethrough, said biasing mechanism including a plastic retainer of circular cross-section, and a retaining ring made of metal, said retainer consisting of a small-diameter portion and a large-diameter portion and formed in an end surface of said retainer with a retaining groove which has two open ends, said end surface of said retainer being positioned in said small-diameter portion, said retaining groove having an enlarged portion formed in said large-diameter portion, said cable extending through said cable hole of said gripping assembly and into said retaining groove of said retainer and having an enlarged end portion confined within said enlarged portion of said retaining groove, said retaining ring being sleeved on said small-diameter portion of said retainer, said enlarged end portion of said cable being sized so as to be unable to remove from said retainer.

4. A wrist and forearm exercise apparatus as claimed in Claim 1, wherein forearm rest. unit includes a counter installed on said front arcuate plate near said connecting portion of said grip assembly, so as to detect and indicate the number of pivotal movement of said grip assembly.

5. A wrist and forearm exercise apparatus as claimed in Claim 1, wherein said resistanc'e adjustment device includes: a spring accommodating tube, fixed on said front arcuate plate so as to receive said compression spring, a portion of said cable, and said anchoring member therein, having a closed rear end, an open front end, and a guiding slot formed through a wall of said spring accommodating tube, said guiding slot having an open end at said open front end of said spring accommodating tube; a knob mounting tube, fixed on said front arcuate plate between said spring accommodating tube and said connecting portion of said grip assembly, aligned with said spring accommodating tube in a coaxial relationship, having a front end positioned near said grip assembly, and a rear end positioned near said spring accommodating tube, said cable extending through said knob mounting tube;; said spring pressing member being an externally threaded rod which extends into said open front end of said spring accommodating tube at one end thereof and into said rear end of said knob mounting tube at the other end of said externally threaded rod, said externally threaded rod including a guide block projecting therefrom into said guiding slot of said spring accommodating tube, so that said externally threaded rod can move axially, but cannot rotate in said spring accommodating tube and said knob mounting tube; and said rotary knob being tubular and having an internally threaded portion engaged with said externally threaded rod, a front end sleeved on said rear end of said knob mounting tube, and a rear end sleeved on said open front end of said spring accommodating tube; whereby, when said rotary knob is rotated, said externally threaded rod moves toward or away from said closed rear end of said spring accommodating tube to press said compression spring against said anchoring member.

6. A wrist and forearm exercise apparatus as claimed in Claim 1, wherein said resistance adjustment device: a spring accommodating tube, fixed on said front arcuate plate so as to receive said compression spring, a portion of said cable, and said anchoring member therein, having a closed rear end and an open front end; a knob mounting tube fixed on said front arcuate plate between said spring accommodating tube and said connecting portion of said grip assembly and having a rear end portion in which said open front end of said spring accommodating tube is press fitted, and an externally threaded front end portion, said cable extending through said knob mounting tube, said rear end portion of said knob mounting tube having an openended guiding slot formed through a wall thereof;; an internally threaded ring engaged with said externally threaded front end portion of said knob mounting tube and including an inward flange projecting radially inwardly from an end portion of said internally threaded ring, said inward flange being spaced apart from said front end of said knob mounting tube at a predetermined distance; said spring pressing member being an internally threaded tubular element which is accommodated within said rear end portion of said knob mounting tube, said tubular element having a guiding block projecting therefrom into said guiding slot of said knob mounting tube, so that said tubular element can move axially, but cannot rotate in said knob mounting tube; ; said rotary knob being generally shaped in the form of a bolt and having a head abutting against an end surface of said externally threaded front end portion of said knob mounting tube, an externally threaded shank engaged within said internally threaded tubular element, an outward flange projecting radially outwardly from said head into the space between said inward flange of said internally threaded ring and said end surface of said knob mounting tube so as to prevent removal of said rotary knob from said knob mounting tube, and a central bore formed through said rotary knob so as to permit said cable to'extend therethrough; whereby, when said head of said rotary knob is rotated, said internally threaded tubular element moves toward or away from said closed rear end of said spring accommodating tube to press said compression spring against said anchoring member.

7. A wrist and forearm exercise apparatus substantially as described hereinbefore with reference to figures 3 to 9 of the accompanying drawings.