TENSIONING MECHANISM

Description

FIELD OF THE INVENTION

The present invention relates to a tensioning mechanism, and in particular to a tensioning mechanism of a portable packaging machine.

BACKGROUND OF THE INVENTION

A portable packaging machine is a portable device that is conveniently carried to a place to strap items. A tensioning mechanism of the portable packaging machine is used to tighten a packing strap after it is wrapped around the items, and its actuator adopts a tensioning wheel and a planetary gear reduction transmission. One-way bearings and pawls are used to prevent loosening in the tensioned state. In the past, there are many connecting gears between the pawl and the electric motor, and the one-way bearing is provided at the ratchet wheel, making the entire connection structure complicated.

SUMMARY OF THE INVENTION

It is an object of the present invention to provide a tensioning mechanism suitable for mounting in a portable packaging machine to avoid a simple loosening structure in a tensioned state. For this purpose, the present invention adopts the following technical solutions:

A tensioning mechanism, which is mounted in a portable packaging machine, the portable packaging machine is provided with a tensioning wheel and a tensioning wheel driving electric motor; a planetary gear speed reduction mechanism is arranged between the tensioning wheel driving electric motor and the tensioning wheel, the tensioning wheel is provided with an inner ring gear, and the inner ring gear is connected to the planetary gear speed reduction mechanism; wherein the planetary gear speed reduction mechanism is provided with a lockable gear ring, the gear ring is provided with an inner ring gear and an outer ring gear which are coaxial with a sun gear, the inner ring gear is in meshing connection with planetary gears, the tensioning mechanism is provided with a locking gear in clutch fit with the outer ring gear, and an output shaft of the driving electric motor is connected to a one-way bearing, so that the output shaft can rotate only in a direction in which the tensioning wheel is driven to tension a strap.

On the basis of adopting the above technical solutions, the present invention may further adopt the following technical solutions, or use these further technical solutions in combination:

The locking gear is connected to a handle, the locking gear is provided with a reset support by an elastic element to maintain a normal state of meshing with an outer ring gear of a lockable gear ring, and the locking gear is capable of being disengaged from the meshing with the outer ring gear by operating a handle.

The locking gear is a tooth block with two teeth.

The planetary gear speed reduction mechanism is set as a multi-stage planetary gear speed reduction mechanism from the output shaft to the tensioning wheel, the output shaft is connected to an output gear, the output gear serves as a sun gear on a first-stage planetary gear speed reduction mechanism, the inner ring gear of the lockable gear ring is in meshing connection with planetary gears of the first-stage planetary gear speed reduction mechanism, the inner ring gear of the tensioning wheel is connected to a final-stage planetary gear speed reduction mechanism by means of a gear connection structure, the sun gears of each stage of the planetary gear speed reduction mechanism are coaxial, and the inner ring gear of the tensioning wheel is coaxial with the sun gear.

An output gear is arranged on the output shaft, the output gear serves as a sun gear on the first-stage planetary gear speed reduction mechanism, the inner ring gear of the lockable gear ring is in meshing connection with the first-stage planetary gear speed reduction mechanism, a planetary carrier of the first-stage planetary gear speed reduction mechanism is connected to a sun gear of the second-stage planetary gear speed reduction mechanism, a planetary carrier of the second-stage planetary gear speed reduction mechanism is connected to a second output gear which is coaxial with the sun gear, the tensioning mechanism is provided with a fixing ring, the fixing ring is provided with an inner ring gear, the fixing ring is fixedly connected to a mounting base, a planetary gear of the second-stage planetary gear speed reduction mechanism is in meshing connection with the inner ring gear of the fixing ring, a plurality of connecting gears which are capable of autoroatation only are arranged on the mounting base around the second output gear, the second output gear is in meshing connection with the connecting gears, the inner ring gear of the tensing wheel is in meshing connection with the connecting gears; the mounting base is rotatably connected to a base, a mounting base reset spring is arranged between the mounting base and the base, such that the mounting base maintains in the normal state located at the tensioning strap working position, and the handle is rotatably connected to the mounting base; the sun gears of each stage of the planetary gear speed reduction mechanism are coaxial, and the inner ring gear of the tensioning wheel is coaxial with the sun gear.

The tensioning mechanism is rotatably mounted on the base, and the tensioning mechanism maintains in the normal state located at the tensioning strap working position by means of a reset spring.

The mounting base is provided with a reset spring hole, a bottom of the reset spring hole is threadedly connected to a plug of a support spring, the base is provided with a reset spring limiting component, one end of the reset spring is placed in the reset spring hole, and the other end is limited by the limiting component.

The tensioning mechanism is provided with a mounting plate and a side cover, the mounting plate and the side cover are located on both sides of the base, the tensioning wheel driving electric motor is located outside the mounting plate and fixedly connected to the mounting plate, the planetary gear speed reduction mechanism and the tensioning wheel are located between the mounting plate and the side cover; the tensioning mechanism is provided with a tensioning mechanism rotating shaft that is connected to the mounting plate, the mounting base and the side cover and passes through the base, the mounting plate and the side cover are fixedly connected to the mounting base.

The output shaft is a shaft with a flat section, and the shaft is connected to the output gear by means of the flat section, a rear end of the output gear is provided with a shaft sleeve with a matching flat section in an inner hole, the sleeve can be fixed as a whole with the output gear or limited at the rear end of the output gear, the shaft sleeve with a flat section in the inner hole is combined with the output shaft with a flat section, the one-way bearing is sleeved outside the shaft sleeve, and the one-way bearing limits the output shaft from rotating in one direction by means of the shaft sleeve.

In the present invention, the number of gears can be reduced in terms of non-returnable one-way transmission and unlocking, and the one-way component is arranged at the power position. When the rotary force is transmitted through the front planetary reduction component, the relative transmission force is relatively small, which is sufficient to achieve a braking effect, such that the tensioning wheel is in a stop state after being tightened. Furthermore, the tensioning mechanism does not need to use a pawl but can use a common tooth shape to lock the inner ring gear outside the planetary gear, and the meshing is stable, which avoids the problems of easy disengagement and unstable matching as a result of single hooks of the teeth to mate a pawl and a ratchet wheel.

The present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is one of three-dimensional schematic diagrams according to an embodiment of the present invention.

FIG. 2 is a three-dimensional schematic diagram observed from another angle according to an embodiment of the present invention.

FIG. 3 is an exploded view of a structure according to an embodiment of the present invention.

FIG. 4 is a schematic diagram of a partial structure according to an embodiment of the present invention.

FIG. 5 is a front view after a side cover is hidden according to an embodiment of the present invention.

DETAILED DESCRIPTION

Referring to figures, the present invention provides a tensioning mechanism, which is mounted in a portable packaging machine. The portable packaging machine is provided with a tensioning wheel 100 and a tensioning wheel driving electric motor 200. A planetary gear speed reduction mechanism is arranged between the driving electric motor 200 and the tensioning wheel 100.

The tensioning wheel 100 is provided with an inner ring gear 101, and the inner ring gear 101 is connected to the planetary gear speed reduction mechanism.

The planetary gear speed reduction mechanism is provided with a lockable gear ring 4, and the gear ring 4 is provided with an inner ring gear 41 and an outer ring gear 42 which are coaxial with a sun gear,, the inner ring gear 41 is in meshing connection with planetary gears, the tensioning mechanism is provided with a locking gear 5 in clutch fit with the outer ring gear 42, and an output shaft 201 of the driving electric motor 200 is connected to a one-way bearing 202, so that the output shaft 201 can rotate only in a direction in which the tensioning wheel 100 is driven to tension a strap. The inner ring of the one-way bearing 202 can be directly connected to the output shaft 201, and can also be connected to a shaft sleeve structure that is anti-rotationally connected to the output shaft 201. For example, when the output shaft 201 is a shaft with a flat section 204, it is connected to the output shaft 201 by means of the flat section 204. A rear end of an output gear 203 is provided with a shaft sleeve 205 with a flat section in an inner hole, and the shaft sleeve 205 can be fixed as a whole with the output gear 203 or limited at the rear end of the output gear 203. The shaft sleeve 205 with the flat section in the inner hole is combined with the output shaft 201 with the flat section 204, and the one-way bearing 202 is sleeved outside the shaft sleeve 205. The one-way bearing 202 limits the unidirectional rotation of the output shaft by means of the shaft sleeve.

The locking gear 5 is connected to a handle 81, the locking gear 5 is provided with a reset support by an elastic element 51 to maintain a normal state of meshing with an outer ring gear 42 of a lockable gear ring 4, and the locking gear 5 is capable of being disengaged from the meshing with the outer ring gear 42 by operating the handle 81 to unlock. The gear ring 4 can rotate such that the planetary gear can only idle when not in operation, and will not drive a planetary carrier or even the tensioning wheel 100 to rotate, providing safety protection. The elastic element 51 can be a compression spring, which is arranged on a mounting base 8 of the portable packaging machine and is located between the handle 81 and the mounting base 8.

The locking gear 5 rotates around a rotation axis of the handle 81, so that the locking gear 5 and the outer ring gear 42 are meshed and separated. Due to the gravity of the handle 81 and the action of the elastic element 51, the locking gear is in a self-locking state when meshed. Preferably, the locking gear is a tooth block with two teeth.

An output gear 203 is arranged on the output shaft 201, the output gear 203 serves as a sun gear on a first-stage planetary gear speed reduction mechanism; the reference numeral 61 represents a planetary gear of the first-stage planetary gear speed reduction mechanism. The output gear 203 is in meshing connection with the planetary gear 61, the planetary gear 61 is mounted on a rotatable planetary carrier 610, and the inner ring gear 41 of the lockable gear ring 4 is in meshing connection with the planetary gear 61 of the first-stage planetary gear speed reduction mechanism. The planetary carrier 610 of the first-stage planetary gear speed reduction mechanism is connected to the sun gear 621 of a second-stage planetary gear speed reduction mechanism. The reference numeral 62 represents a planetary gear of the second-stage planetary gear speed reduction mechanism, and the sun gear 621 is in meshing connection with the planetary gear 62. The planetary gear 62 is mounted on a rotatable planetary carrier 620, and the planetary carrier 620 of the second-stage planetary gear speed reduction mechanism is connected to a second output gear 631 which is coaxial with the sun gear.

The tensioning mechanism is provided with a fixing ring 7, the fixing ring 7 is provided with an inner ring gear 71, a planetary gear 62 of the second-stage planetary gear speed reduction mechanism is in meshing connection with the inner ring gear 71. The fixing ring 7 is fixedly connected to the mounting base 8 and cannot rotate relative to the mounting base 8. A plurality of connecting gears 63 which are capable of autoroatation only are arranged on the mounting base 8 around the second output gear 631, the second output gear 631 is in meshing connection with the connecting gears 63. An inner ring gear 101 arranged on the tensioning wheel 100 is in meshing connection with the connecting gear 63.

The tensioning mechanism is rotatably mounted on the base 300, and the tensioning mechanism maintains in the normal state located at the tensioning strap working position by means of a reset spring 82. The mounting base 8 is rotatably connected to the base 300, and a mounting base reset spring 82 is arranged between the mounting base 8 and the base 300 to maintain the mounting base 8 in the normal state located at the tensioning strap working position. The reset spring 82 can be a compression spring. The handle 81 is rotatably connected to the mounting base 8, and is used to lift the tensioning mechanism when threading the strap, and meanwhile, after the handle is lifted, the locking gear 5 is automatically unlocked. The reference numeral 86 represents a handle shaft.

Further, the reset spring 82 is adjustable, the mounting base 8 is provided with a reset spring hole 86, and a bottom of the reset spring hole 86 is threadedly connected to a plug 87 of a support spring, and the base 300 is provided with a reset spring limiting component (for example, a long bolt 85). One end of the reset spring 82 is placed in the reset spring hole 86, and the other end is sleeved in and limited by the long bolt 85. When adjustment is required, the mounting base 8 can be rotated to open and the plug 87 can be adjusted from the bottom. After the adjustment is completed, the mounting base 8 is lowered, and the plug 87 is in a position that is not easily misoperated, which helps to ensure the reliability of the device after commissioning.

The sun gears of various stages of planetary gear speed reduction mechanisms are coaxial, the inner ring gear 101 of the tensioning wheel 100 is coaxial with the sun gear, and the inner ring gear 71 of the fixed ring is coaxial with the sun gear.

The tensioning mechanism is provided with a mounting plate 83 and a side cover 84, and the mounting plate 83 and the side cover 84 are located on both sides of the base 300. The base is provided with a through elliptical hole 301 and a fixing tooth block 302 that cooperates with the tensioning wheel for the tensioning mechanism to pass through. The tensioning wheel driving electric motor 200 is located outside the mounting plate 83 and is fixedly connected to the mounting plate 83. The planetary gear speed reduction mechanism and the tensioning wheel 100 are located between the mounting plate 83 and the side cover 84; the tensioning mechanism is provided with a tensioning mechanism rotating shaft 85 that is connected to the mounting plate 83, the mounting base 8 and the side cover 84 and passes through the base 300, and the mounting plate 83 and the side cover 84 are fixedly connected to the mounting base 8.

Unless otherwise specified, in the description of the present invention, the orientation or position relationship indicated by terms such as “upper”, “lower”, “vertical”, “horizontal”, “top”, “bottom”, “inside”, “outside”, “axial”, etc. is based on the orientation or positional relationship shown in the figures, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the indicated device or element must have the particular orientation, construction and operation in the particular orientation, therefore, the terms describing the orientation or position relationship in the present invention are only used for illustrative purposes and cannot be understood as limitations on the present invention. A person of ordinary skill in the art can understand the specific meaning of the above terms in combination with the accompanying drawings according to specific circumstances.

Unless otherwise clearly specified and limited, in the present invention, the terms “provided/arranged”, “clamped” and “connected” should be construed in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected, or indirectly connected through an intermediate medium, or it can be internal communication between two elements. A person of ordinary skill in the art can understand the specific meaning of the above terms according to specific circumstances.

The foregoing description merely describes the specific embodiments of the present invention, but the structural features of the present invention are not limited thereto. Any changes or modifications made by those skilled in the art in the field of the present invention shall fall within the scope of protection of the present invention.