WO2008099429A1

WO2008099429A1 - Treadmill with endless belt tension adjusting device

Info

Publication number: WO2008099429A1
Application number: PCT/IT2007/000096
Authority: WO
Inventors: Giorgio Parise
Original assignee: Cammax S.A.; Cammax International Ltd.
Priority date: 2007-02-14
Filing date: 2007-02-14
Publication date: 2008-08-21
Also published as: TW200944258A

Abstract

A treadmill comprises a frame having a base (12), a transmission device having a front roller and a rear roller (21) connected between two sides of said base (12), an endless belt (22) driven over said front and rear rollers, and an adjusting device for adjusting the tension of the endless belt (22) that includes two identical units (32) respectively connected to the two sides of the base (12), each unit (32) comprising a movable member (31) which is a substantially C-shaped member and has a passage defined therethrough, a threaded rod (37) connected to said passage, and an adjusting nut (35) rotatably mounted to a distal end of said threaded rod (37) extending beyond said movable member (31). A shaft of the rear roller (21) is connected to the two movable members (31) of the adjusting device so that, by operating the two adjusting nuts (35), the two movable members (31) are moved in the horizontal direction so as to adjust the distance between the front and rear rollers and the tension of the endless belt (22) without using electric power and with a simple and compact mechanism.

Description

"TREADMILL WITH ENDLESS BELT TENSION ADJUSTING DEVICE"

FIELD OF THE INVENTION

The present invention relates to a treadmill with an endless belt tension adjusting device, and in particular to a treadmill with a device for manually adjusting the tension of the endless belt.

BACKGROUND OF THE INVENTION

A conventional treadmill generally includes a device for adjusting the tension of the endless belt by controlling the distance between the two rollers over which the endless belt is driven. This is usually achieved by moving the rear roller that has a shaft with projecting threaded end sections, each end section being engaged with a respective threaded rod which is in turn engaged with a worm gear reduction device driven by a motor. When the endless belt is loosened, the user may activate the motors so as to drive the worm gear reduction devices and the threaded rods which spin without movement in the horizontal direction and the threaded sections of the rear roller shaft move so as to adjust the distance between the two rollers.

Although effective, such an adjusting device involves the presence of two motors and two worm gear reduction devices, both of which are costly. Besides, these components combined with the threaded rods and threaded end sections of the roller shaft make up a rather bulky device that takes up precious space.

Furthermore, a motorized adjusting device obviously implies the use of electric power and therefore can not be applied to non-motorized treadmills, i.e. treadmills in which the endless belt is driven over the two rollers by the user's push as he walks on the belt.

The object of the present invention is to provide a treadmill with an endless belt tension adjusting device which overcomes the above-mentioned drawbacks.

This object is achieved by means of a treadmill wherein the distance between the two rollers can be manually adjusted and the adjusting device includes a compact and simple mechanism. SUMMARY OF THE INVENTION

The present invention relates to a treadmill which comprises a frame having a base with a front roller and a rear roller connected between two sides of the base, and an endless belt is driven by the front and rear rollers. An adjusting device includes two identical units which are respectively connected to two sides of the base. Each unit has a movable member which is a substantially C-shaped member and includes a passage defined therethrough, a threaded rod being connected to said passage and an adjusting nut being rotatably mounted to the threaded rod. The shaft of the rear roller is connected to the two movable members of the adjusting device so that, by operating the two adjusting nuts, the two movable members are moved in the horizontal direction so as to adjust the distance between the front and rear rollers and the tension of the endless belt.

The present invention will become more obvious from the following description when taken in connection with the accompanying drawings which show, for purposes of illustration only, a preferred embodiment in accordance with the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

Fig.l is a perspective view to show the treadmill with the endless belt tension adjusting device of the present invention; Fig.2 is a partial exploded view to show the above treadmill with a detail of the endless belt tension adjusting device;

Fig.3 is a partial sectional perspective view to show the shaft of the rear roller engaged with a slot of the movable unit of the endless belt tension adjusting device; Fig.4 is a partial sectional longitudinal view to show the shaft of the rear roller engaged with the slot of the movable unit via an opening defined in a top of the movable member;

Fig.5 is a view similar to Fig.4 that shows how the rear roller is shifted by rotating the adjusting nut of the endless belt tension adjusting device; and Fig.6 is a partial see-through top view to show that the endless belt tension adjusting device of the present invention is connected to the two sides of the treadmill base.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to figures 1 to 3, the treadmill comprises a frame 10 having a rectangular base 12 and two posts 11, that extend from the base 12 so as to be connected with a handle and a control panel.

A transmission device 20 is connected between the two sides of the base 12 and includes a motor (not shown), a front roller 210 and a rear roller 21. The front roller 210 is connected to the front end of the base 12 between the two sides of the base 12, and the rear roller 21 is connected to the rear end of the base 12 between the two sides of the base 12. An endless belt 22 is driven by the motor through the front and rear rollers 210, 21.

An adjusting device 30 is connected to the rear end of the base 12 and includes two identical units 32 respectively connected to the two sides of the base 12. Each unit 32 has a movable member 31 which is a substantially C-shaped member and is movably received in respective one of two casings 33, which are fixed to two respective insides of the two sides of the base 12. Each movable member 31 has a passage defined therethrough which has a stepped shoulder, and a threaded rod 37 extends through the passage of each movable member 31 and has a head which is stopped by the stepped shoulder. A distal end of the threaded rod 37 extends beyond the side of the movable member 31 and the casing 33, and an adjusting nut 35 is rotatably mounted to the distal end of the threaded rod 37.

Each movable member 31 has a slot defined therethrough that communicates via an opening 322 defined through a top of the movable member 31. The slot has an inner end 321 and the shaft of the rear roller 21 enters into the slot via the opening 322 and is shifted to contact the inner end 321 of the slot as shown in Figs. 3 and 4. Each movable member 31 has scale markings 36 defined in a top surface thereof and each casing 33 has a window 34 defined in a top thereof such that the scale markings 36 of the movable member 31 are located corresponding to the window 34. As shown in Fig.5, when rotating the adjusting nuts 35, the threaded rods 37 together with the movable members 31 are moved because of the engagement of the heads of the threaded rods 37 with the stepped shoulders in the passages. The user may check the scale markings 36 via the windows 34 to ensure that the two movable members 31 are shifted the same distance. Therefore, the tension of the endless belt 22 can be easily and precisely adjusted by the user without using electric power.

While we have shown and described the above embodiment in accordance with the present invention, it should be clear to those skilled in the art that further embodiments may be made without departing from the scope of the present invention as defined by the appended claims.

Claims

CLAMS

1. A treadmill comprising a frame (10) having a base (12), a transmission device (20) having a front roller (210) and a rear roller (21) connected between two sides of said base (12), an endless belt (22) driven over said front and rear rollers (210, 21), and an adjusting device for adjusting the tension of said endless belt (22), characterized in that said tension adjusting device includes two identical units (32) respectively connected to said two sides of the base (12), each unit (32) comprising a movable member (31) which is a substantially C-shaped member and has a passage defined therethrough, a threaded rod (37) connected to said passage, and an adjusting nut (35) rotatably mounted to a distal end of said threaded rod (37) extending beyond said movable member (31), a shaft of the rear roller (21) being connected to the two movable members (31) of the adjusting device.

2. The treadmill as claimed in claim 1, characterized in that each movable member (31) has a slot defined therethrough that communicates via an opening (322) defined through a top of the movable member (31), said slot having an inner end (321) and the shaft of the rear roller (21) entering into the slot via said opening (322) and being shifted to contact said inner end (321) of the slot.

3. The treadmill as claimed in claim 1 or 2, characterized in that each movable member (31) has scale markings (36) defined in a top surface thereof.

4. The treadmill as claimed in any of the preceding claims, characterized in that two casings (33) are respectively connected to the two sides of the base (12) and the two movable members (31) are movably received in in respective one of said two casings (33).

5. The treadmill as claimed in claims 3 and 4, characterized in that each casing (33) has a window (34) defined in a top thereof and the scale markings (36) of the movable member (31) received in each casing (33) are located corresponding to said window (34).

6. The treadmill as claimed in any of the preceding claims, characterized in that the passage defined through each movable member (31) includes a stepped shoulder and the threaded rod (37) includes a head which is stopped by said stepped shoulder.

7. The treadmill as claimed in any of the preceding claims, characterized in that the endless belt (22) is driven over the front and rear rollers (210, 21) by a motor.