INTEGRATED ROLLER FOR A TREADMILL, METHOD FOR MAKING AND A SPECIAL-PURPOSE EXTRUSION TOOL
An integrated roller for a treadmill is comprised of rollers, the said rollers are of integrated structure with the outer end and the inner end integrated, the outer diameter surface of the said inner end and the inner hole surface of the said outer end form close fit or clearance fit, and the tip of the inner end extends inward along the inner diameter direction for a distance to form a plateau shape. The making method thereof comprises an extrusion and an inverted extrusion by a mold. This utility model features material saving, simple structure and less process steps in making and makes up the drawback of prior art rollers of high raw materials consumption, complicated structure and complicated making process. This invention is used for treadmill rollers.
This invention generally relates to a fitting part for a fitness apparatus, specifically, it relates to an integrated roller for a treadmill, and also to a method for making the same and an extrusion tool for use in the said method.
BACKGROUND ARTThe existing rollers of treadmill have structures as shown in
The technical problem to be solved by this invention is to provide an integrated roller for a treadmill featuring material saving, simple structure and less process steps in making in order to make up the drawback that the making process is relatively complicated of prior art rollers, in addition, this invention also provides a method for making the integrated roller for a treadmill and a special-purpose mold for use in the said method.
To solve the technical problem, the technical scheme adopted in this invention is that an integrated roller for a treadmill is comprised of rollers, the said rollers are of integrated structure with the outer end and the inner end integrated, the outer diameter surface of the said inner end and the inner hole surface of the said outer end form close fit or clearance fit, and the tip of the inner end extends inward along the inner diameter direction for a distance to form a plateau shape.
The said clearance is 0-6 mm.
Inside the said clearance, solid glue or iron ring is configured.
The said roller is of cylinder or cone shape.
To make the above integrated roller for treadmills, the making method according to this invention comprises the following several steps:
a. Firstly prepare raw blank, place the blank on a lower fixed plate, then compact the blank using an upper compaction plate, and then carry out a first-time extrusion to the blank using a female mold; in this way, a steel tube with round end is extruded into a tube with arcuate end, and after the completion of this step, a second step is followed.
b. The second step is to place the blank that has gone through the first-time extrusion on a lower fixed plate, and compact with an upper compaction plate, then carry out inverted extrusion to the blank using a male mold so that the outer diameter surface of the inner end and the inner hole surface of the outer end form close fit or clearance fit; in this way, a half finished product with shape as shown in
To allow the formation of close fit or clearance fit between the outer diameter surface of the inner end and the inner hole surface of the outer end in the above method, a special-purpose mold should be used. Such mold includes a male mold and a female mold, the said female mold has a tapering hole configured inside the front end body, the front end of the hole is horizontal, the middle is arc transition section, and the rear end is horizontal; the said male mold has a boss with tapering fillet configured on the front end, at the same time, the boss and the rear end of the male mold are in tapering fillet transition connection.
This invention has the following advantageous effects:
1. The outer end and the inner end are of integrated structure, then when bearing squeezes the inner end of the roller, and the inner end of the roller will transfer the applied force to the outer end, at the same time, the thickness of the end where bearing is installed is one times thicker than before and it's a whole body, so the inner end has less tendency to deform, thus the service life is prolonged, besides, the raw material consumption is low and the structure is simple, and according to experiments, it is proved that when the same torque is transferred, this integrated roller is superior to the one shown in
2. The tip of the inner end extends inward along the inner diameter direction for a distance, and then when operating, the roller can more effectively fix the bearing and thus improve the practical effect of the product.
3. The outer diameter surface of the inner end and the inner hole surface of the outer end form clearance fit, then when the difference between the outer diameter of the steel tube and the outer diameter of the bearing is too large, the clearance formed at the ends can be utilized to clear up the fit clearance between the outer diameter of the steel tube and the bearing, thus this invention can be used with bearings of different specifications, the practicability of this invention is improved, and better application effect as well as the lower cost are achieved.
4. Inside the ends clearance is configured with solid glue or iron ring, the glue or ring functions to cushion the squeeze applied from the bearing to the inner end, thus allowing the long time service of the product.
5. This invention adopts mold extrusion method for processing, so the process steps are reduced and the cost is saved.
In the figure:
1. steel tube, 11. thickened steel tube, 2. iron sleeve, 3. iron sleeve with cap, 4. integrated roller, 41. outer end, 411. inner hole surface of outer end, 412. tip of outer end, 42. inner end, 421. outer diameter surface of inner end, 422. tip of inner end, 43. ends clearance, 44. plateau, 5. bearing, 6. lower fixed plate, 7. upper compaction plate, 8. female mold, 81. tapering hole, 9. steel tube gone through a first-time molding, 10. male mold, 101. boss, 11. solid glue.
MODE FOR CARRYING OUT THE INVENTIONAs shown in
As shown in
As shown in
As shown in
As shown in
The working principle adopted in this invention is: the product according to this invention is driven by a belt pulley fitted over its outer surface and thus drives the belt on the treadmill roller.
The making method thereof comprises:
Firstly prepare raw blank, place the blank on a lower fixed plate 6 of a horizontal oil hydraulic press, then compact the blank using an upper compaction plate 7, and then carry out the first-time extrusion to the blank using a female mold 8, in this way, a steel tube with round end is extruded into a tube with arcuate end, and after the completion of this step, the second step is followed.
The second step is to place the blank that has gone through the first-time extrusion on a lower fixed plate 6 of a horizontal oil hydraulic press, compact with an upper compaction plate 7, then carry out inverted extrusion to the steel tube that has gone through the first-time molding 9 using a male mold 10 with different outer diameter so that the outer diameter surface of the inner end 421 and the inner hole surface of the outer end 422 form close fit or clearance fit, in this way, a half finished product with shape as shown in
The mold adopted in this invention includes a male mold 10 and a female mold 8, the said female mold 8 has a tapering hole 81 configured inside the front end body, the front end of the hole 81 is horizontal, the middle is arc transition section, and the rear end is horizontal, the said male mold 10 has a boss 101 with tapering fillet configured on the front end, at the same time, the boss 101 and the support are in tapering fillet transition connection.
Before the application of the finished product, bearing 5 is placed into the plateau 44 under the squeeze of a squeezer of this invention.
In order to have better application performance in this invention, solid glue 11 or iron ring can be configured at the ends clearance to cushion the squeeze applied from the bearing 5 to the inner end 42, so as to realize better application effect of this invention.
The metal roller of this invention may be of cylindrical or arcuate shape, and this invention can be applicable for rollers used in conveying machinery field.
Claims
1. An integrated roller for a treadmill comprised of rollers, which is characterized in that the said rollers are of integrated structure with the outer end (41) and the inner end (42) integrated, the outer diameter surface of the said inner end (421) and the inner hole surface of the said outer end (411) form close fit or clearance fit, and the tip of the inner end (422) extends inward along the inner diameter direction for a distance to form a plateau shape.
2. An integrated roller for a treadmill according to claim 1, which is characterized in that the said clearance is 0-6 mm.
3. An integrated roller for a treadmill according to claim 1, which is characterized in that inside the said clearance is configured with solid glue (11) or iron ring.
4. An integrated roller for a treadmill according to claim 1 or 3, which is characterized in that the said roller is of cylindrical or arcuate shape.
5. A method for making an integrated roller for a treadmill according to claim 1, which is characterized in that the said method comprises the following several steps:
- a. Firstly prepare raw blank, place the blank on a lower fixed plate (6) of a horizontal oil hydraulic press, then compact the blank using an upper compaction plate (7), and then carry out a first-time extrusion to the blank using a female mold (8), in this way, a steel tube with round end is extruded into a tube with arcuate end, and after the completion of this step, the second step is followed.
- b. The second step is to place the blank that has gone through the first-time extrusion on a lower fixed plate (6) of a horizontal oil hydraulic press, compact with an upper compaction plate (7), then carry out inverted extrusion to the steel tube that has gone through the first-time molding (9) using a male mold (10) with different outer diameter so that the outer diameter surface of the inner end (421) and the inner hole surface of the outer end (422) form close fit or clearance fit, in this way, a half finished product shape is formed, and after the completion of this step, the half finished product is further processed to have a plateau (44) for bearing (5) placing to finish the production of a finished product in this invention.
6. A method for making an integrated roller for a treadmill according to claim 5, which is characterized in that the said processing is by the method of lathe machining or mold extrusion.
7. A special-purpose mold to realize a making method for an integrated roller of a treadmill according to claim 5 or 6, which is characterized in that such mold includes a male mold (10) and a female mold (8), the said female mold (8) has a tapering hole (81) configured inside the front end body, the front end of the hole (81) is horizontal, the middle is arc transition section, and the rear end is horizontal, the said male mold (10) has a boss (101) with tapering fillet configured on the front end, at the same time, the boss (101) and the support are in tapering fillet transition connection.
Type: Application
Filed: Jun 13, 2008
Publication Date: Oct 22, 2009
Inventor: Sheng Ju Zheng (Hubei)
Application Number: 12/138,825
International Classification: A63B 22/02 (20060101);