KR200306046Y1 - Vibration absorption type inverter driving three phase inertia motor for treadmills - Google Patents

Abstract

The present invention relates to a motor for a treadmill, in particular, by applying a dustproof structure to the motor itself to prevent the vibration generated when the motor is driven to the frame and the running belt of the treadmill without having a separate dustproof means, flywheel The present invention relates to a three-phase inertial motor driven by a vibration absorbing inverter for a treadmill that can prevent the bearing from being damaged by distributing the load of the drive shaft to a bearing supporting the drive shaft by mounting the shaft on the opposite side of the drive pulley.

The three-phase inertial motor for driving a vibration absorbing inverter for a treadmill according to the present invention is a drive shaft of the rotor 14 with bearings 13 and 13 'fixed to the inside of the stator 12 and built into both sides thereof. A motor main body 10 rotatably supporting 15 and penetrating both ends of the drive shaft 15; A first dustproof member (18) surrounding the outer ring of each bearing (13) (13 '); A drive pulley 60 mounted to one end of the drive shaft 15; A flywheel 100 mounted on the other end of the drive shaft 15 to distribute the load of the rotor 14 to each bearing 13, 13 'and increase inertia; It consists of a support plate 21 in contact with the bottom and a support plate 22 extending upwards from the front and rear ends of the support plate 21 and both ends of the motor body 10 are seated and supported thereon, thereby providing the motor main body 10. Pedestal 20 for supporting in a supported state; And a second anti-vibration member 30 which is wrapped on both ends of the motor body 10 and seated on the seating surface of the support plate 22.

Description

VIBRATION ABSORPTION TYPE INVERTER DRIVING THREE PHASE INERTIA MOTOR FOR TREADMILLS}

The present invention relates to a motor for a treadmill, in particular, by applying a dustproof structure to the motor itself to prevent the vibration generated when the motor is driven to the frame and the running belt of the treadmill without having a separate dustproof means, flywheel The present invention relates to a three-phase inertial motor driven by a vibration absorbing inverter for a treadmill that can prevent the bearing from being damaged by distributing the load of the drive shaft to a bearing supporting the drive shaft by mounting the shaft on the opposite side of the drive pulley.

Treadmills are generally referred to as treadmills and are one of the indoor fitness equipment developed by the user so that the user can walk or run the desired time at various speeds and inclination angles, and the treadmill frame (as shown in FIGS. 1 and 2). 1) Between the interlocking roller (2) and the idle roller (3) installed therein, a wide running belt (4) is mounted in an endless track, and the interlocking pulley (5) is axially coupled to the front interlocking roller (2). The interlocking pulley 5 is connected to the drive pulley 6b and the interlocking belt 7 axially coupled to the drive shaft 6a of the electric motor 6 installed in front of the frame 1.

The treadmill is operated when the user operates the control unit 8 electrically connected to the electric motor 6 in a state where the user climbs on the running belt 4, and the electric motor 6 is driven, and the driving pulley 6b and As the interlocking roller 2 rotates by rotating interlocking of the interlocking pulley 5 connected to the interlocking belt 7, the running belt 4 is rotated and the running belt 4 is rotated. By controlling the speed of the electric motor 6 by the operation of 8), it is used while adjusting the intensity of the running motion.

On the other hand, the rotation characteristics of the electric motor 6 transmits the rotation of the rotor through the drive shaft 6a coupled to the center of the rotor, the drive shaft 6a is precisely coupled to the shaft center of the rotor shaft Even if it is, because it protrudes to the distance dimension required for use, vibration occurs during rotation. In addition, the electric motor 6 causes continuous rotation to the rotor by alternating application of alternating current power, but if analyzed strictly, the rotation of the rotor is maintained by the rotational inertia when the AC power is cut off. It is a well-known fact that the vibration caused by the drive shaft 6a is larger than the rotational vibration generated at the high speed during low speed rotation.

In the conventional motor of the conventional treadmill having the characteristics as described above, as shown in Figure 3, the motor body of the electric motor for driving the running belt and the support for it is formed integrally, so that the electric motor in the treadmill frame as it is When installed, the rotating vibration generated when the rotor embedded in the motor main body is transmitted to the treadmill frame through the pedestal as it is, the treadmill frame and various devices mounted thereon may be damaged due to vibration, and the treadmill frame As the vibration transmitted to the running belt is transmitted as it is, the user has a problem that the user feels the noise due to the vibration and the vibration during exercise and has a discomfort. Thus, in order to reduce vibrations transmitted from the electric motor to the frame of the treadmill, there is an inconvenience of providing a separate dustproof member between the electric motor and the treadmill frame.

In addition, when the driving pulley is mounted so as to be integrally contacted with the driving shaft, the rotational vibration generated when the rotor is rotated is transferred to the running belt through the driving pulley, the interlocking belt, and the interlocking roller. In addition to feeling the noise, the vibration generated from the running belt during exercise was also transmitted to the drive shaft through the interlocking roller, the interlocking belt and the driving pulley, there was also a problem that the quiet operation of the motor is not made.

In addition, the load is concentrated on one end of the drive shaft to which the drive pulley is mounted when the drive shaft is rotated, so that the load is concentrated on a bearing adjacent to one end of the drive shaft among the two bearings supporting the drive shaft. Bearings were more susceptible to breakage than other bearings due to friction and the resulting temperature rise.

In addition, the motor body has a problem that the cooling efficiency is reduced because the cooling is made through heat exchange with the outside air in the cooling fin formed on the outside. In this case, a method of cooling a motor main body by using a separate cooling fan mounted on a drive shaft is used, but this requires additional cost and has an external dimension increase.

Accordingly, the present invention has been devised to solve the conventional problems as described above, by applying a vibration-proof structure to itself, the vibration generated when the motor body is driven without having a separate dust-proof means, the frame and running of the treadmill. The purpose of the present invention is to provide a vibration-absorbing inverter drive three-phase inertial motor for a treadmill that can be prevented from being transferred to a belt to prevent damage to various devices and allow the user to move without feeling discomfort in a stable state.

In addition, by installing a flywheel with a blade hole on the opposite side of the drive pulley, by distributing the load to each bearing supporting the drive shaft to prevent the damage of the bearing, and also strong to the motor body through the blade hole when the flywheel rotates without a separate cooling fan An object of the present invention is to provide a three-phase inertial motor driven by a vibration absorbing inverter for a treadmill that cools the motor body by blowing wind.

1 is a side cross-sectional view of a treadmill showing an installation structure of a conventional drive-drive three-phase motor for a treadmill;

2 is a plan sectional view of the treadmill shown in FIG.

3 is a perspective view of the motor shown in FIGS. 1 and 2;

Figure 4 is a perspective view of a three-phase inertial motor driving vibration absorbing inverter for a treadmill according to an embodiment of the present invention.

Figure 5 is a side cross-sectional view of the treadmill applied vibration-driven inverter drive three-phase inertial motor for a treadmill according to an embodiment of the present invention.

6 is a plan sectional view of the treadmill shown in FIG.

FIG. 7 is a sectional view taken along line VIII-VIII in FIG. 6; FIG.

8 is a sectional view taken along line VII-VII of FIG. 7.

9 is a sectional view taken along line VII-VII of FIG. 7.

10 is a partially exploded perspective view showing a coupling structure of a drive shaft and a drive pulley according to another embodiment of the present invention.

Figure 11 is a partially exploded perspective view showing a coupling structure of the drive shaft and the drive pulley according to another embodiment of the present invention.

<Description of Main Reference Codes in Drawings>

10: motor body 11: housing

12: stator 13, 13´: bearing

14: rotor 15: drive shaft

16: end bracket 17: lead wire

18: first dustproof member 20: pedestal

21: support plate 22: support plate

23: fixed plate 30: the second dustproof member

40: connection band 50: push rod

60: driving pulley 70, 70´: bush

80, 80´: Dust washer 100: Flywheel

The three-phase inertial motor driving the vibration absorbing inverter for a treadmill according to the present invention includes a motor body for rotatably supporting a drive shaft of a rotor with bearings fixed to an inner side and built-in bearings on both sides thereof and penetrating both ends of the drive shaft. ; A first dustproof member surrounding the outer ring of each bearing; A drive pulley mounted to one end of the drive shaft; A flywheel mounted on the other end of the drive shaft to distribute the load of the rotor to each bearing and to increase inertia; A support plate extending from the front and rear ends of the support plate and supporting plates on which both ends of the motor body are seated and supported on the upper portion, supporting the motor body in a supported state; And a second dustproof member which is wrapped on both ends of the motor body and seated on the seating surface of the support plate.

In addition, the vibration absorption type inverter drive three-phase inertial motor for a treadmill according to a preferred feature of the present invention, characterized in that it further comprises a tension control means for adjusting the tension of the interlock belt mounted on the drive pulley by moving the pedestal horizontally. It is done.

In addition, the vibration absorption type inverter drive three-phase inertial motor for a treadmill according to a preferred feature of the present invention is interposed between the drive pulley and the drive shaft to reduce the vibration transmitted to the running belt of the treadmill through the drive pulley when the drive shaft rotates. Characterized in that it further comprises a bush.

According to a preferred feature of the present invention, the flywheel is characterized in that a plurality of blade holes for blowing air to the motor body when the rotor rotates.

Hereinafter, the characteristics and the functions of the above-described components will be described in more detail with reference to preferred embodiments of the vibration absorbing inverter driving three-phase inertial motor for a treadmill according to the present invention.

4 of the accompanying drawings is a perspective view of a three-phase inertial motor driving a vibration absorption inverter for a treadmill according to an embodiment of the present invention, Figure 5 is a vibration absorption type inverter driving for a treadmill according to an embodiment of the present invention A side cross-sectional view of the treadmill showing the installation structure of the three-phase inertial motor, FIG. 6 is a plan cross-sectional view of the treadmill shown in FIG. 5, FIG. 7 is a cross-sectional view of FIG. 6, and FIG. 8 is a cross-sectional view of FIG. VII-VII sectional drawing and FIG. 9 is VII-VII sectional drawing of FIG.

As shown, the three-phase inertial motor driving the vibration absorption inverter for a treadmill according to an embodiment of the present invention, the base 20 for supporting the motor main body 10 and the motor main body 10 in a supported state. And a drive pulley 60 mounted at one end of the drive shaft 15 and a flywheel 100 mounted at the other end of the drive shaft 15.

The motor body 10 includes a hollow housing 11 in which a stator 12 is fixed inside, and a rotor 14 shielding both ends of the housing 11, and bearings 13 and 13 ′ installed therein. It is composed of a pair of end brackets (16) rotatably supporting the drive shaft (15) and penetrating both ends of the drive shaft (15).

At this time, the stator 12 is composed of a fixed core 12a fixed to the inside of the housing 11 and a coil 12b wound around the fixed core 12a, and the coil 12b is coil 12b from the outside. A lead wire 17 for applying power to the housing 17 is connected through the side wall of the housing 11. Therefore, when power is applied to the coil 12b of the stator 12 through the lead wire 17, a magnetic field is generated, and the rotor 14 rotates by this magnetic field.

On the other hand, each bearing 13 (13 ′) is wrapped with a first dust-proof member 18 of a special synthetic resin to prevent the vibration generated when the rotor 14 is rotated to each end bracket 16, respectively. .

The pedestal 20 is manufactured separately from the motor main body 10 to support the motor main body 10 in a supported state. The support plate 21 is in contact with the bottom of the treadmill frame 200 and the support plate 21. It is composed of a pair of support plates 22 extending from the front and rear ends vertically upward, and having a seating groove formed thereon in which the bearing 16a of the end bracket 16 is seated and supported.

Here, each end bracket 16 is seated in a seating groove of each support plate 22 of the pedestal 20 in a state in which the second dustproof member 30 is wrapped in the shaft number 16a, and the connection band 40 is formed in a divided manner. Each hook groove 40a and each locking piece 22a of the support plate 22 are firmly hooked and fixed by the fixing screw operation.

Therefore, the vibration generated during the rotation of the rotor 14 is primarily reduced by the first dustproof member 18 and the vibration transmitted to the end bracket 16 in the reduced state is again returned by the second dustproof member 30. Since it is reduced, the vibration transmitted to the treadmill frame 200 through the pedestal 20 is very weak, so that the user can enjoy the exercise on the running belt 210 without feeling the interference of the noise due to the vibration and vibration. In addition, damage to various devices mounted on the treadmill frame 200 is prevented.

On the other hand, on both sides of the support plate 21, a plurality of long holes 21a through which fixing bolts for fixing the support plate 21 to the inner bottom of the treadmill frame 200 are formed, respectively, on one side of the treadmill frame The pinned plate 23 extends vertically upward to correspond to the fixed plate 201 extending vertically upward from the inner bottom of the 200. Then, the fixing plate 201 is bolted to the push rod 50 for pushing the pinned plate 23 to its end position. Therefore, the base plate 21 is moved by loosening the fixing bolt for fixing the base plate 21 to the bottom of the treadmill frame 200 and rotating the rod 50 to push the pin plate 23 to the end thereof, thereby moving the base plate 21. The tension of the interlocking belt 220 mounted on the pulley 60 is adjusted.

The drive pulley 60 is mounted to one end of the drive shaft 15, and is connected to the interlocking pulley 231 and the interlocking belt 220 of the interlocking roller 230 for rotating the running belt 210 to the rotor ( By transmitting the rotational force of 14) to the interlocking roller 230, the running belt 210 is rotated.

In this case, as shown in FIG. 8, the vibration generated when the motor body 10 is driven between the driving pulley 60 and the driving shaft 15 is transmitted to the running belt 210 through the interlocking belt 220. In addition to preventing, on the contrary, a plurality of bushes 70 having a bar shape are provided to prevent vibrations generated when the user moves on the running belt 210 from being transmitted to the drive shaft 15 through the interlocking belt 220. In addition, a predetermined gap is formed between the driving shaft 15 and the driving pulley 60, and a plurality of bushes 70 are interposed between the outer circumference of one end of the driving shaft 15 and the inner circumference of the driving pulley 60 opposite thereto. Grooves 15a and 60a are formed, respectively.

On the other hand, the drive shaft 15 is formed stepped so that the diameter gradually decreases from the center to both ends, in order to mount the drive pulley 60 to one end of the drive shaft 15, first, the step surface of the drive shaft 15 and The vibration washer 80 for blocking contact with one end surface of the driving pulley 60 is fitted to the driving shaft 15, and the driving pulley 60 is mounted. Then, the bush 70 is interposed between the grooves 15a and 60a formed to face the drive shaft 15 and the drive pulley 60, and the bush 70 includes the drive shaft 15 and the drive pulley 60. In addition to reducing the vibration between the drive shaft 15 and the drive pulley 60 simultaneously plays the role of a key so as not to be idle. As described above, after the bush 70 is interposed, the bolt 90 in which the anti-vibration washer 80 is fitted is fastened to the fastening groove formed at one end surface of the drive shaft 15, thereby preventing the drive pulley 60 from being separated.

The flywheel 100 has its own mass to increase the inertia when the drive shaft 15 rotates and is mounted on two bearings 13 and 13 ′ mounted to the other end of the drive shaft 15 to support the drive shaft 15. By distributing the load of the rotor 14, the temperature rise and uneven wear of the bearings 13 and 13 'generated during load concentration are prevented, thereby extending the life of the bearings 13 and 13'. In addition, the flywheel 100 has a plurality of blade holes (100a) are formed so that the strong wind is transmitted to the motor main body 10 through the blade hole (100a) when the drive shaft 15 is rotated (coil of the motor body 10 ( 12b) is cooled. At this time, the blade hole 100a has a larger cross-sectional area at the inlet side than at the outlet side.

Meanwhile, as shown in FIG. 9, similar to the driving pulley 60, a plurality of bushes 70 ′ serving as a dustproof function and a key are interposed between the flywheel 100 and the driving shaft 15, and the driving shaft 15. The departure of the flywheel 100 is prevented by the bolt 90 'fastened to the other end of the drive, and the driving pulley 60 is provided between both side surfaces of the flywheel 100 and the stepped surface of the drive shaft 15 and the bolt 90'. Similarly, the dust washer 80 'is interposed.

Referring to the operation of the three-phase inertial motor driving the vibration absorption type inverter for treadmill according to an embodiment of the present invention configured as described above.

First, when the user operates the control unit electrically connected to the motor in a state where the user climbs on the running belt 210, power is applied to the coil 12b of the stator 12 through the lead wire 17 to rotate the rotor 14. Is rotated, due to the rotational force of the driving pulley 60 and the interlocking roller 230 is rotated by the rotation linkage of the interlocking pulley 231 connected to the interlocking belt 220 by rotating the running belt 210 mounted thereon Running is performed, and by controlling the speed of the electric motor by the operation of the control unit according to the user's preference during the exercise is used while adjusting the strength of the running movement.

During this process, the vibration and noise generated by the rotation of the rotor 14 are first wrapped in the outer ring of the pair of bearings 13 and 13 ′ supporting the drive shaft 15 in the motor body 10. It is primarily reduced by the anti-vibration member 18, and is reduced again by the second anti-vibration member 30 wrapped in each end bracket 16 from the outside of the motor body 10, so that the treadmill 20 is a treadmill. The vibration transmitted to the frame 10 is very weak. In addition, since the transmission of vibration from the drive shaft 15 to the drive pulley 60 is prevented due to the bush 70 and the dust washer 80 interposed between the drive pulley 60 and the drive shaft 15, the interlocking belt 120. There is no vibration transmitted to the running belt 210 through.

Accordingly, damage to the treadmill frame 200 and various devices mounted thereon may be prevented, and the user may enjoy the movement in a stable state without receiving any interference of noise due to vibration and vibration on the running belt 210. In addition, since the vibration generated when the user moves on the running belt 210 is also not transmitted to the motor body 10, the motor body 10 is quietly operated.

On the other hand, the load is evenly distributed to each of the bearings 13 and 13 'supporting the rotation of the drive shaft 15 by the flywheel 100 mounted at the other end of the drive shaft 15, so that the respective bearings 13 and 13'. Not only prolongs its life, but also a strong wind is applied to the motor body 10 through the blade hole (100a) formed in the flywheel (100) generated in the coil 12b of the stator 12 without a separate cooling fan The heat to be cooled can be effectively cooled.

When the user is exercising for a long time on the running belt 210, the driving belt pulley 60 and the interlocking pulley 231 is mounted, the interlocking belt 220 for transmitting the rotational force of the rotor 14 to the interlocking pulley is loosened running belt ( The rotation force of 210 is weakened. Therefore, in this case, loosen the fixing bolt for fixing the support plate 21 of the pedestal 20 to the bottom of the treadmill frame 200, and rotates the rod 50 is bolted to the fixed plate 201 of the frame 200 By moving the position 20, the tension of the interlocking belt 220 can be easily adjusted.

10 of the accompanying drawings is a cross-sectional view showing a coupling structure of the drive shaft 15 and the drive pulley 60 according to another embodiment of the present invention. 4 to 9, the same reference numerals denote the same members having the same function.

As shown, according to the vibration-absorbing inverter drive three-phase inertial motor for a treadmill according to another embodiment of the present invention, the drive pulley (60 ') can be formed separated into two pulleys (61, 62). have. Therefore, in order to mount each pulley part 61 and 62 to the drive shaft 15, first, each pulley part 61 and 62 is loosely wrapped in the drive shaft 15, and the outer periphery of the drive shaft 15 and each pulley are After the bar-shaped bush 70 is formed in the grooves 15a and 60'a formed on the inner circumference of the portions 61 and 62, the pulleys 61 and 62 are firmly secured with bolts and nuts. Tighten. Then, by fastening the bolt 90 in which the anti-vibration washer 80 is fitted into the fastening groove formed at the end of the drive shaft 15, the drive pulley 60 ′ is prevented from being separated in the longitudinal direction of the drive shaft 15.

Hereinafter, the operation of the vibration-absorbing type inverter driving three-phase inertial motor for a treadmill according to another embodiment of the present invention is the same as the operation according to an embodiment of the present invention will be omitted.

Figure 11 of the accompanying drawings is a partially exploded perspective view showing a coupling structure of the drive shaft and the drive pulley according to another embodiment of the present invention.

As shown, according to the vibration-absorbing inverter drive three-phase inertial motor for a treadmill according to another embodiment of the present invention, the drive pulley (60 ˝) is formed by separating the two pulleys (63) (64), Each bush 70 'is formed in a ring shape, and a plurality of grooves 15 in which a ring-shaped bush 70' is interposed between the inner circumference of each pulley portion 63 and 64 and the outer circumference of the drive shaft 15 are formed. 'A) (60'a) is formed to face in the circumferential direction. The drive pulley 60 'is integrally rotated with the drive shaft 15 by the key 110.

Hereinafter, the operation of the vibration-absorbing inverter drive three-phase inertial motor for a treadmill according to another embodiment of the present invention is the same as the operation according to an embodiment of the present invention will be omitted.

As described above with reference to the accompanying drawings, the three-phase inertial motor driving the vibration absorption inverter for treadmills according to the preferred embodiments of the present invention, the present invention is not limited to the embodiments and drawings described in detail in the specification As such, various modifications may be made within the technical spirit of the present invention.

According to the vibration absorption type inverter drive three-phase inertial motor for a treadmill of the present invention as described in detail above, the first vibration-proof member is wrapped in a pair of bearing outer races rotatably supporting the drive shaft inside the motor body, The second vibration damping member is wrapped in the tentacles of the end brackets respectively seated on the support plate, so that vibration generated when the rotor is rotated is not transmitted to the treadmill frame through the pedestal, thereby preventing damage to various devices mounted on the treadmill frame. In addition to preventing, the user can enjoy the exercise in a stable state without any interference from the vibration and the resulting noise on the running belt.

In addition, since a plurality of bushes are interposed between the driving pulley and the driving shaft, the vibration transmitted to the running belt of the treadmill through the driving pulley when the driving shaft rotates and the vibration transmitted to the driving shaft through the driving pulley when the running belt rotates are reduced. Not only can the user enjoy the exercise in a stable posture on the running belt, but also the quiet driving can be performed in the motor body.

In addition, by mounting a flywheel formed with a blade hole at the other end of the drive shaft, the load is evenly distributed to each bearing supporting the drive shaft, thereby extending the life of the bearing, and because strong wind is transmitted to the motor body through the hole, Without the cooling fan, it is possible to effectively cool the heat generated in the coil of the stator.

In addition, by loosening the fixing bolts for fixing the pedestal to the bottom of the treadmill frame and rotating the push rod bolted to the fixing plate of the treadmill frame, the pedestal is configured to move the position, it is possible to easily adjust the tension of the interlocking belt mounted on the drive pulley. .

Claims (8)

A motor body having a stator fixed inside and rotatably supporting a drive shaft of the rotor with bearings embedded in both sides thereof, and passing through both ends of the drive shaft; A first dustproof member surrounding the outer ring of each bearing; A drive pulley mounted to one end of the drive shaft; A flywheel mounted on the other end of the drive shaft to distribute the load of the rotor to the bearings and to increase inertia; A support plate extending from the front and rear ends of the support plate and supporting plates on which both ends of the motor body are seated and supported on the upper portion, supporting the motor body in a supported state; And A vibration absorbing inverter driving three-phase inertial motor for a treadmill, characterized in that it comprises a second dustproof member wrapped on both ends of the motor body and seated on the seating surface of the support plate. The method of claim 1, And a tension adjusting means for adjusting the tension of the interlocking belt mounted to the driving pulley by horizontally moving the pedestal. 3. The method of claim 1, The driving pulley is a vibration-absorbing inverter drive three-phase inertial motor for a treadmill, characterized in that formed by two separate pulleys. The method according to claim 1 or 3, Interposed between the drive pulley and the drive shaft, a vibration absorbing inverter drive for a treadmill, characterized in that further comprising a bush for reducing the vibration transmitted to the running belt of the treadmill through the drive pulley when the drive shaft rotates. 3-phase inertial motor. The method of claim 4, wherein The bush is formed in a bar shape, a predetermined gap is formed between the drive shaft and the drive pulley, the bar-shaped bush is interposed between the outer periphery of one end of the drive shaft and the inner periphery of the drive pulley opposite thereto. A three-phase inertial motor for driving a vibration absorbing inverter for a treadmill, characterized in that a plurality of grooves are formed in the longitudinal direction, respectively. The method of claim 4, wherein The bush is formed in a ring shape, a predetermined gap is formed between the drive shaft and the drive pulley, and the ring-shaped bush is interposed between an outer circumference of one end of the drive shaft and an inner circumference of the drive pulley opposite thereto. A three-phase inertial motor for driving a vibration absorbing inverter for a treadmill, wherein a plurality of grooves are formed in the circumferential direction, respectively. The method of claim 1, The flywheel vibration-absorbing inverter drive three-phase inertial motor for the treadmill, characterized in that a plurality of blade holes for blowing air to the motor body when the rotor is rotated. The method of claim 2, The tension control means, A fixed plate extending upward on the support plate to correspond to a fixed plate extending upwardly from the bottom of the frame inside of the treadmill; And And a push rod which is bolted to the fixed plate and pushes the fixed plate to the end thereof to move the position thereof. 3.