CN111534944B

CN111534944B - Sewing machine's frame

Info

Publication number: CN111534944B
Application number: CN202010475314.2A
Authority: CN
Inventors: 蔡炳清; 黄小青; 祝书伟; 徐智; 张鑫媛
Original assignee: Jack Sewing Machine Co Ltd
Current assignee: Jack Technology Co Ltd
Priority date: 2020-05-29
Filing date: 2020-05-29
Publication date: 2021-08-06
Anticipated expiration: 2040-05-29
Also published as: CN111534944A

Abstract

The invention provides a frame of a sewing machine, belongs to the technical field of sewing machine accessories, and solves the technical problems of inconvenient movement, poor adaptability and the like of the frame structure of the existing sewing machine. The machine frame comprises two tubular bases, wherein an upright column is vertically and fixedly arranged on each base, an upper supporting pipe and a lower supporting pipe are movably inserted into two ends of each base respectively, a lower rack is arranged on the lower side of the lower supporting pipe, and an upper rack is arranged on the upper side of the upper supporting pipe; a meshing gear is arranged between the upper rack and the lower rack, and a lower transmission shaft is connected to the meshing gear; each upright post is provided with a vertical lifting pillar in a sliding manner, and an upper transmission shaft capable of driving the lifting pillar to move up and down is arranged below the lifting pillar; the upright post is also provided with a driving shaft which can respectively drive the upper transmission shaft and the lower transmission shaft to rotate; supporting leg components are arranged at the bottoms of the outer ends of the upper supporting tube and the lower supporting tube. The rack in the invention is convenient to move; and the distance between the supporting leg components and the height of the bedplate can be adjusted, and the adaptability is strong.

Description

Sewing machine's frame

Technical Field

The invention belongs to the technical field of sewing machine accessories, and relates to a frame of a sewing machine.

Background

Usually, a complete set of sewing machine is mainly composed of a sewing machine, a table, a frame and other accessories, wherein the frame of the sewing machine is used as the table and a carrier of the sewing machine, and is an indispensable part of the sewing machine. The frame of sewing machine generally is through the foot cup support of each installation of four angles, and simultaneously for convenient removal, some frames comprise two truckles and two foot cups, only need to lift up just can convenient removal sewing machine on one side like this. However, both of the above solutions have disadvantages: for example, when the four corners are all supported by the foot cups, although the height of the foot cups is adjustable, the adaptability to the ground is better, the friction coefficient between the foot cups and the ground is larger, the whole size of the sewing machine is relatively larger, in addition, the whole weight of the sewing machine is generally about 80Kg, and at the moment, the time, the labor and the efficiency are low as long as the sewing machine is lifted by a plurality of people or is carried by the sewing machine to move; in contrast, although the sewing machine supported by the two casters and the two foot cups is relatively easy to move, the heights of the casters cannot be adjusted, so that the adaptability of the frame to the ground is poor, the casters are in line-surface contact with the ground, the contact area is small, the friction force is small, and the sewing machine with the structure is difficult to stably place, and the sewing effect is influenced.

Meanwhile, although the types of sewing machines are more, the frame and the bedplate of most of the mainstream sewing machines are basically similar in structure and appearance, the various types of sewing machines are different in working rotating speed, whole machine weight, overall dimension and working principle, so that the frame table of the sewing machine is required to have strong adaptability, however, different vibration of machines on the table plate of the existing frame has larger difference at different rotating speeds, which directly influences the sewing effect and the comfort of operators, the vibration of the table plate is an important influence factor of the machines and the frame besides the self material and structure reason, and the calculation finds that the sewing machine can generate larger unbalanced inertia force in the axial direction, the gravity direction and the front-back direction during the operation process, the size of the rack in the axial direction is far larger than that of the rack in the front-back direction, and the adaptability and adjustability of the rack in the current market are generally poor.

In addition, some sewing machine table heights on the market are fixed, and some sewing machine table heights are adjustable. For the bedplate with fixed height, people with different heights are inconvenient to use; and to height-adjustable's platen, although make things convenient for the people of different heights to use, but current adjustment mode is fairly loaded down with trivial details, not only need take off sewing machine, still needs special instrument to carry out the dismouting, needs two people to cooperate the installation simultaneously at least, and its altitude mixture control's practicality is lower. When the height of the sewing machine table is increased, a new problem occurs. For example, the vibration of the whole sewing machine is increased rapidly, and the risk of overturning is increased, because the height of the gravity center position of the sewing machine leads to the increase of the moment arm corresponding to the unbalanced force in the operation process, thereby causing the increase of the vibration of the whole sewing machine, and the increase of the vibration seriously affects the sewing performance and reduces the comfort of operators; adaptation of the support structure of the gantry is therefore also required.

For example, Chinese patent (publication No. CN203923637U, publication No. 2014-11-05) discloses a sewing machine frame comprising: the supporting beam on two sides, the cross beam at the top of the supporting beam and connected with the sewing machine table are connected with a transverse plate and a pedal plate mounting frame between the two supporting beams, the pedal plate mounting frame is detachably connected with the lower part of the supporting beam, an upper connecting plate and a lower connecting plate are arranged on the inner side of the supporting beam, flanges are arranged at the upper end and the lower end of the transverse plate, two screws respectively penetrate through the flanges and the upper connecting plate and the lower connecting plate and are locked through nuts, and the transverse plate and the supporting beam are movably and detachably connected.

The sewing machine frame in the above patent document is supported by four foot cups, is inconvenient to move, has poor adjustability and universality, and can not adjust the height of a bedplate arranged on the frame, thereby influencing the convenience and the comfort of use.

Disclosure of Invention

The invention provides a frame of a sewing machine according to the problems in the prior art, and the technical problems to be solved by the invention are as follows: how to improve the stability, adjustability and use convenience and comfort of the sewing machine frame.

The purpose of the invention can be realized by the following technical scheme:

a frame of a sewing machine comprises two tubular bases which are longitudinally arranged at intervals, wherein an upright post is vertically and fixedly arranged on each base; the upper rack and the lower rack are oppositely arranged, a meshing gear capable of driving the upper rack and the lower rack to longitudinally move simultaneously is arranged between the upper rack and the lower rack, and a lower transmission shaft is connected to the meshing gear; a vertical lifting support column is slidably arranged on each upright column, a supporting plate is arranged at the upper end of each lifting support column, and an upper transmission shaft capable of driving the lifting support columns to move up and down is arranged below each lifting support column; the upright post is also provided with a driving shaft which can respectively drive the upper transmission shaft and the lower transmission shaft to rotate; supporting leg components with casters are mounted at the bottoms of the outer ends of the upper supporting tube and the lower supporting tube.

The working principle is as follows: a table plate is arranged on the supporting splint, and a main body part of the sewing machine is arranged on the table plate. The four groups of supporting leg assemblies are further provided with the leg cups, when the frame of the sewing machine is in an initial position, the distance between the front and the back of the four groups of supporting leg assemblies and the distance between the left and the right of the four groups of supporting leg assemblies are the same as the distance between the original frame, and the vibration of the bedplate can be reduced by increasing the distance between the front and the back of the two supporting leg assemblies due to the fact that the vibration of the bedplate is large. The specific operation is that before the driving shaft rotates, the state of the four supporting foot components is firstly confirmed, and normally, when the bedplate is fixed, the machine frame is supported by the foot cups on the supporting foot components, and the lowest points of the foot cups are lower than the lowest points of the trundles, so that the trundles are suspended, and the machine frame in the state is more stable because the contact area of the foot cups and the ground is larger and the friction force is larger. In order to go up supporting tube and bottom suspension fagging around realizing in the base that supporting tube and bottom suspension fagging can be quick, the sliding friction who needs four truckles converts rolling friction into, only need adjust the height of foot cup this moment, treat when four foot cups's minimum is higher than the truckle minimum, four truckles and ground direct contact, replace sliding friction by rolling friction, go up the rotation effect of last rack on the supporting tube and the lower rack on the bottom suspension fagging under the meshing gear, can make things convenient for quick realization back-and-forth movement. The purpose of changing the front-back distance of the supporting leg assemblies is achieved, the adaptability of the bedplate is further expanded, and the bedplate with the minimum distance of the supporting leg assemblies is selected according to different rotating speeds of different machine types to vibrate; meanwhile, as the supporting leg assemblies are provided with the trundles, when the rack needs to be moved, the foot cups are lifted, the bedplate rack and the machine can be conveniently and quickly moved to any position, when a preset destination is reached or the bedplate which can be accepted vibrates, the same steps are repeated at the moment, the foot cups are descended to a proper position, the lowest surfaces of the four foot cups are lower than the lowest surfaces of the trundles, the four trundles are suspended, and the foot cups play a supporting role. In addition, the upper transmission shaft is driven by the driving shaft to rotate, the lifting support column is driven to move up and down, the height of the bedplate is adjusted, and the requirements of different users are met.

In the frame of the sewing machine, bearing seats are fixedly arranged on the side surface of the upright post at intervals from top to bottom, bearings are arranged in the bearing seats, and vertical lead screws are inserted in the two bearings; the side surface of the lifting support is fixedly provided with a nut sliding block which is screwed on the screw rod, the lower end of the screw rod is fixedly provided with a bevel gear, and the end part of the upper transmission shaft is fixedly provided with a bevel gear meshed with the bevel gear.

The rotation that realizes the drive shaft among this technical scheme through lead screw and screw slider cooperation turns into the linear motion of lift pillar, and the lead screw is preferred trapezoidal lead screw among this structure, and it itself has self-locking performance, consequently its can not appear rotating and then lead to the downstream of platen because of the effect of gravity under the condition of vertical placing. According to the installation mode of the invention, the screw rods on the left side and the right side have to be opposite in rotation direction. The lifting support column is inserted on the upright column and is tightly attached to the upright column, and the upright column is fixed, so that the upright column plays a role in guiding when the lifting support column moves up and down.

In the frame of the sewing machine, the side surface of the upright post is provided with a long-strip-shaped limiting hole, the length direction of the limiting hole is vertically arranged, and a first limiting screw is inserted into the limiting hole. Preferably, one side of each limit screw is provided with two limit screws which are arranged at intervals up and down and are respectively lower limit and upper limit, so that the nut sliding block is effectively prevented from colliding with the bearing seat due to the rotation of the screw rod.

The adjustment range of the bedplate height can be selected according to the actual model, and under the condition that other conditions are not changed, the length of the screw rod and the length of the limiting hole are only required to be changed. And meanwhile, the position of the first limiting screw is correspondingly modified. Particularly, when the position of the bedplate rises due to the rising of the gravity center of the machine, under the action of the unbalanced inertia force of the machine, the vibration of the bedplate and the machine can be increased due to the lengthening of the acting force arm, when the condition occurs, the distance between the supporting foot components on the front side and the rear side can be increased by combining the supporting foot component distance adjusting mechanism, and the specific distance increasing distance can be tested in advance according to different machine types. Due to the combination of the mechanism with the adjustable distance between the supporting foot components, the problem that the vibration is increased only when the bedplate in the lifting bedplate structure is used is solved.

In the frame of the sewing machine, the upper transmission shaft consists of two sections, the inner ends of the two sections of upper transmission shafts are connected through an upper connecting shaft sleeve, the outer ends of the two sections of upper transmission shafts are provided with helical gears, and the two helical gears respectively correspond to the screw rods on the stand columns on the two sides; the lower transmission shaft is also composed of two sections, the inner ends of the two sections of lower transmission shafts are connected through a lower shaft sleeve, the outer ends of the two sections of lower transmission shafts are respectively provided with a meshing gear, and the two meshing gears respectively correspond to the upper rack and the lower rack on the bases on the two sides. The upper transmission shaft simultaneously drives the two bevel gears to rotate, so that the screw rods on the stand columns on the two sides are synchronously driven to rotate, synchronous lifting adjustment of the lifting support columns on the left side and the right side is realized, and the bedplate is driven to stably lift; the lower transmission shaft simultaneously drives the meshing gears at the two ends to rotate, so that the synchronous adjustment of the space between the four supporting leg assemblies is realized.

In the frame of the sewing machine, the driving shaft is respectively sleeved with the first belt pulley and the second belt pulley and can axially move, a clamping protrusion in a multi-pyramid shape is arranged between the first belt pulley and the second belt pulley on the driving shaft, and clamping grooves matched with the clamping protrusion are formed in the opposite sides of the first belt pulley and the second belt pulley; when the driving shaft moves axially, the clamping protrusions can form clamping circumferential limit with the two clamping grooves respectively; one of them section go up the last transmission shaft and have set firmly belt pulley three, the cover is equipped with driving belt one on belt pulley one and the belt pulley three, one of them section the last belt pulley four that has set firmly of lower transmission shaft, the cover is equipped with driving belt two on belt pulley two and the belt pulley four.

When the driving shaft drives the first belt pulley to rotate clockwise, the rotation of the first belt pulley realizes the clockwise rotation of the third belt pulley through the first driving belt, meanwhile, the upper driving shaft fixed together with the third belt pulley and the bevel gear on the upper driving shaft also rotate clockwise, the bevel gear on the screw rod is meshed with the bevel gear, the bevel gear also rotates clockwise at the moment when viewed from top to bottom, and further the screw rod fixedly connected with the bevel gear also rotates clockwise, the two bearing blocks are fixed on the upright post and used for supporting the screw rod, the screw nut sliding block is fixed on the lifting support and meshed with the screw rod, and when the screw rod rotates clockwise, the screw nut sliding block meshed with the screw rod can move downwards along with the screw rod to drive the lifting support to move downwards, so that the descending of the bedplate is realized; according to the same principle, the screw rod on the other side rotates rightwards and anticlockwise rotates to synchronously drive the lifting support on the side to move downwards so as to realize the downward movement of the bedplate. When the bedplate is required to be lifted, the driving shaft drives the belt pulley to rotate anticlockwise.

The second belt pulley and the fourth belt pulley are connected through a second transmission belt, when the driving shaft rotates anticlockwise, the second transmission belt synchronously rotates in the same direction, and the fourth belt pulley is fixed on one section of the lower transmission shaft through two tacking screws. The fourth belt pulley drives the lower transmission shaft and the meshing gear on the lower transmission shaft to rotate, the upper rack on the upper supporting pipe and the lower rack on the lower supporting pipe are meshed with the meshing gear simultaneously, when the meshing gear rotates anticlockwise, the upper rack on the upper supporting pipe and the lower rack on the lower supporting pipe respectively move forwards and backwards in a straight line, and the distance between the supporting leg assembly on the upper supporting pipe and the supporting leg assembly on the lower supporting pipe is more and more far. In the same way, when the distance between the supporting leg components on the front side and the rear side is required to be reduced, only the meshing gear needs to rotate clockwise.

In the gear rack structure, the front supporting leg assembly and the rear supporting leg assembly move back and forth according to the distance of 1:1, and when the same gear is changed into a double gear, the module and the tooth number of the gear are changed, so that the front supporting leg assembly and the rear supporting leg assembly can move according to a required proportion.

The number of the upper supporting tubes and the number of the lower supporting tubes are respectively 2, and according to actual requirements, only the front 2 lower supporting tubes or the rear 2 upper supporting tubes can be reserved, and other mechanisms can be unchanged.

In the frame of the sewing machine, the stand column is fixedly provided with a supporting seat, the supporting seat is provided with two belt seat bearings at intervals, and the first belt pulley and the second belt pulley are respectively arranged on the two belt seat bearings; a connecting sleeve is fixedly arranged at one end of the driving shaft, and a gear shifting connecting rod is axially fixed and circumferentially rotatably sleeved on the connecting sleeve; the gear shifting connecting rod is characterized in that a through hole is formed in the supporting seat, a partition plate for partitioning the lower portion of the through hole into two clamping grooves is arranged on the lower side of the through hole, and the outer end of the gear shifting connecting rod can be clamped in the clamping grooves; and a pre-tightening spring is sleeved between the bearing with the seat and the connecting sleeve on the driving shaft.

In view of space limitation and manufacturing cost, the two mechanisms rotate only by one set of driving mechanism, the first belt pulley and the second belt pulley are respectively arranged on the two bearings with the base, shaft end snap springs are arranged at the shaft ends of the first belt pulley and the second belt pulley to prevent the first belt pulley and the second belt pulley from axially moving, the driving shaft simultaneously penetrates through the first belt pulley and the second belt pulley and is in clearance fit with the first belt pulley and the second belt pulley, the pre-tightening springs are arranged on the driving shaft, are placed between the connecting sleeve and the bearing with the base and are in contact with the end surfaces of the first belt pulley and the second belt pulley, the connecting sleeve is fixed on the driving shaft, the gear shifting connecting rod is arranged on the connecting sleeve and is. When the gear shifting connecting rod is respectively positioned in the two clamping grooves, the end face of the gear shifting connecting rod can be tightly attached to the clamping groove face of the clamping groove due to the existence of the pre-tightening spring, and the gear shifting connecting rod is ensured not to shake due to vibration of the sewing machine. During shifting, only the manual rotation is needed to shift the gear connecting rod to a proper angle and loosen the axial force on the driving shaft, the driving shaft can automatically axially move for a distance under the action of the pre-tightening spring, and because the device only has two gears to be switched, the pre-tightening force of the pre-tightening spring can directly push the driving shaft to another proper gear position, then the gear shifting connecting rod is manually and rotatably placed in another clamping groove, and then the movement of supporting leg assembly interval adjustment and bedplate lifting adjustment can be realized only by rotating the driving shaft. Similarly, the drive shaft is pressed inwards, and then the gear shifting connecting rod is rotated to the other clamping groove.

Because the driving shaft needs to be switched between the first belt pulley and the second belt pulley and well meshed with the first belt pulley and the second belt pulley, and because the two sets of mechanisms are operated independently, the angles between the first belt pulley and the second belt pulley are different definitely and can be designed into a hexahedral structure with a slope, the hexahedral structure with the slope has good alignment, and no matter how much the angles between the first belt pulley and the second belt pulley are different, due to the slope, when the clamping protrusion of the driving shaft is contacted with the first belt pulley or the second belt pulley, the clamping groove with 60 degrees can be automatically corrected, so that the meshing of the driving shaft and the first belt pulley or the second belt pulley is realized.

In the frame of the sewing machine, the upper side of the base is in threaded connection with the second limit screw, the upper rack is provided with a strip-shaped hole along the length direction of the upper rack, and the second limit screw is movably inserted into the strip-shaped hole. The second limit screw has the main function of preventing the upper rack and the lower rack from moving excessively when being meshed with the meshing gear, so that the upper rack and the lower rack are disengaged from the meshing gear or the upper support pipe and the lower support pipe collide with each other.

In the frame of the sewing machine, the supporting leg assembly further comprises a mounting frame and a foot cup, the caster wheel is rotatably connected to the mounting frame through a rotating support, the rotating support is located on one side of the caster wheel, an adjusting screw and a locking nut are installed on the rotating support, and the foot cup is hinged to the lower end of the adjusting screw. The height of the caster is fixed and can not be adjusted, the height of the foot cup can be adjusted by screwing the adjusting screw rod and the locking nut through the wrench, and the bottom surface of the foot cup can be higher than or lower than the lowest point of the bottom surface of the caster according to different working conditions. Preferably, the caster is a universal wheel, and the rotating bracket is rotatably connected with the mounting frame, so that the caster can rotate 360 degrees and is convenient to move; the foot cup is connected with the adjusting screw rod in a spherical hinge mode, so that the foot cup can generate a certain inclination, and the stand can be kept stable on uneven ground; through adjusting screw and lock nut's setting, make adjusting screw's height-adjustable, consequently supporting legs assembly can adjust its height according to actual conditions to select to use truckle or foot cup according to actual need.

In the frame of the sewing machine, the driving shaft is connected with a driving motor or a driving handle; the two bases are both in a square tubular shape and are arranged in parallel at intervals, a connecting plate for mounting a pedal is fixedly connected between the two bases, and a reinforcing longitudinal beam is fixedly connected between the two upright columns. Therefore, the pedal can be conveniently installed, and the stability and the reliability of the installation are improved. In the technical scheme, the driving of the driving shaft can be manual or electric, and for manual operation, only a hand-operated wrench and other driving handles are needed to be added at the end part of the driving shaft; if the electric driving mechanism needs to be changed into an electric driving mechanism, a small change needs to be made on the existing structure, namely, a similar air cylinder is added in the axial direction of the driving shaft to realize the switching of the axial gears of the driving shaft, and then a set of servo motor is added to realize the axial rotation of the driving shaft.

Compared with the prior art, the rack has the following advantages:

1. according to the invention, the four foot cups on the original rack are all changed into the supporting foot component structure with the adjusting foot cup and the universal caster, and the supporting foot component with the caster is utilized to realize quick and efficient movement of the sewing machine, so that manpower and material resources are saved, and the working efficiency is improved; support through descending the foot cup when needing fixed mounting, guarantee the reliable and stable nature, and ball articulated foot cup is stronger to the adaptability on ground, makes the frame more steady.

2. The invention improves through a group of mechanical mechanisms, so that the supporting foot components on the front side and the rear side of the frame can randomly adjust the distance within a certain range; thereby adapting to different sewing machine requirements, improving stability, reducing shaking and vibration and reducing overturning risks.

3. According to the invention, by adding a set of lifting mechanism, the original platform plate height can be changed from the unadjustable height to the height which can be adjusted randomly within a certain range, and the adaptability, the universality and the comfort of a user are improved.

Drawings

Fig. 1 is a schematic structural diagram for mounting and using the rack.

Fig. 2 is a schematic perspective view of the stand.

Fig. 3 is a partially enlarged schematic view of a portion a in fig. 2.

Fig. 4 is a partially enlarged structural view at B in fig. 2.

Fig. 5 is a partial structural schematic diagram of the rack.

Fig. 6 is a schematic perspective view of the supporting leg assembly in the frame.

Fig. 7 is a partial structural schematic diagram of the second rack.

In the figure, 1, a base; 2. a column; 2a, limiting holes; 3. an upper support tube; 3a, an upper rack; 3a1, strip shaped holes; 4. a lower support tube; 4a, a lower rack; 5. a meshing gear; 6. a lower transmission shaft; 7. a lifting column; 8. a support pallet; 9. an upper transmission shaft; 10. a drive shaft; 10a, clamping protrusions; 11. a support leg assembly; 11a, a caster; 11b, a foot cup; 11c, a mounting rack; 11d, rotating the bracket; 11e, adjusting the screw rod; 11f, locking the nut; 12. a bearing seat; 13. a lead screw; 14. a nut slide block; 15. a bevel gear; 16. a helical gear; 17. a first limit screw; 18. an upper connecting shaft sleeve; 19. the lower shaft sleeve is connected; 20. a first belt pulley; 21. a second belt pulley; 22. a clamping groove; 23. a third belt pulley; 24. a belt pulley IV; 25. a first transmission belt; 26. a second transmission belt; 27. a supporting seat; 27a, a through hole; 27b, a partition plate; 27c, a clamping groove; 28. a pedestal bearing; 29. connecting sleeves; 30. a shift link; 31. pre-tightening the spring; 32. a second limit screw; 33. a connecting plate; 34. reinforcing the longitudinal beam; 35. a platen.

Detailed Description

As shown in fig. 1 to 7, the frame of the sewing machine comprises two tubular bases 1 which are longitudinally arranged at intervals, wherein a vertical column 2 is vertically and fixedly arranged on each base 1, an upper supporting tube 3 and a lower supporting tube 4 are respectively and movably inserted at two ends of each base 1, a lower rack 4a which extends towards the inside of the base 1 is arranged at the lower side of the lower supporting tube 4, and an upper rack 3a which extends towards the inside of the base 1 is arranged at the upper side of the upper supporting tube 3; the upper rack 3a and the lower rack 4a are oppositely arranged, an engaging gear 5 capable of driving the upper rack 3a and the lower rack 4a to longitudinally move simultaneously is arranged between the upper rack 3a and the lower rack 4a, and a lower transmission shaft 6 is connected to the engaging gear 5; each upright post 2 is provided with a vertical lifting support post 7 in a sliding manner, the upper end of each lifting support post 7 is provided with a supporting plate 8, and an upper transmission shaft 9 capable of driving the lifting support post 7 to move up and down is arranged below each lifting support post 7; the upright post 2 is also provided with a driving shaft 10 which can respectively drive the upper transmission shaft 9 and the lower transmission shaft 6 to rotate; the bottom of the outer ends of the upper supporting tube 3 and the lower supporting tube 4 are respectively provided with a supporting leg assembly 11 with a caster 11a and a foot cup 11 b.

In this embodiment, a table 35 is mounted on the support plate 8, and a main body of the sewing machine is mounted on the table 35. When the frame of the sewing machine is at an initial position, the distance between the front and the back of the four groups of supporting foot components 11 and the distance between the left and the right of the four groups of supporting foot components 11 are the same as the distance between the original frame, and now because the bedplate 35 vibrates greatly, the vibration of the bedplate 35 can be reduced by increasing the distance between the front and the back supporting foot components 11. The specific operation is that before the driving shaft 10 rotates, the state of the four supporting leg assemblies 11 is firstly confirmed, and normally, when the bedplate 35 is fixed, the frame is supported by the leg cups 11b on the supporting leg assemblies 11, and the lowest points of the leg cups 11b are lower than the lowest points of the caster wheels 11a, so that the caster wheels 11a are suspended, because the contact area of the leg cups 11b and the ground is larger, the friction force is also larger, and the frame in the state is more stable. In order to go up supporting tube 3 and lower support tube 4 can be quick realize flexible around in base 1, the sliding friction that needs four truckles 11a converts rolling friction into, only need adjust the height of foot cup 11b this moment, treat that four foot cup 11 b's the lowest face is higher than the truckle 11a when the lowest face, four truckles 11a and ground direct contact, replace sliding friction by rolling friction, go up under the rotation effect of last rack 3a on the supporting tube 3 and the lower rack 4a on the lower support tube 4 meshing gear 5, can make things convenient for quick realization back-and-forth movement. The purpose of changing the front-back distance of the supporting foot components 11 is achieved, the adaptability of the bedplate 35 is further expanded, and the bedplate 35 with the minimum distance between the supporting foot components 11 is selected according to different rotating speeds of different machine types to vibrate; meanwhile, as the caster wheels 11a are arranged on the supporting leg assemblies 11, when the rack needs to be moved, the foot cups 11b are lifted, the bedplate 35 rack and the machine can be conveniently and quickly moved to any position, when a preset destination is reached or the bedplate 35 which can be accepted vibrates, the same steps need to be repeated at the moment, the foot cups 11b are lowered to a proper position, the lowest surfaces of the four foot cups 11b are lower than the lowest surfaces of the caster wheels 11a, the four caster wheels 11a are suspended, and the foot cups 11b play a supporting role. In addition, the driving shaft 10 drives the upper transmission shaft 9 to rotate, so that the lifting support 7 is driven to move up and down, the height of the bedplate 35 is adjusted, and the requirements of different users are met.

Specifically, as shown in fig. 1 to 4, bearing blocks 12 are fixedly arranged on the side surfaces of the upright posts 2 at intervals from top to bottom, bearings are arranged in the bearing blocks 12, and vertical lead screws 13 are inserted into the two bearings; the side surface of the lifting support 7 is fixedly provided with a nut sliding block 14, the nut sliding block 14 is screwed on a screw rod 13, the lower end of the screw rod 13 is fixedly provided with a bevel gear 15, and the end part of the upper transmission shaft 9 is fixedly provided with a bevel gear 16 meshed with the bevel gear 15. In the embodiment, the rotation of the driving shaft 10 is converted into the linear motion of the lifting support 7 through the matching of the lead screw 13 and the nut slider 14, in the structure, the lead screw 13 is preferably a trapezoidal lead screw 13 which has self-locking performance, so that the downward movement of the bedplate 35 caused by the rotation due to the action of gravity can not occur under the condition of vertical placement. According to the installation mode of the invention, the screw rods on the left side and the right side have to be opposite in rotation direction. In the invention, the lifting support post 7 is inserted on the upright post 2 and is tightly attached with the upright post 2, and the upright post 2 is fixed, so that the upright post 2 plays a role in guiding when the lifting support post 7 moves up and down. Furthermore, the side surface of the upright post 2 is provided with a long-strip-shaped limiting hole 2a, the length direction of the limiting hole 2a is vertically arranged, and a first limiting screw 17 is inserted into the limiting hole 2 a. Preferably, two limiting screws (17) are arranged on one side of each limiting screw at intervals up and down, namely a lower limiting screw and an upper limiting screw, so that the nut sliding block (14) is effectively prevented from colliding with the bearing seat (12) due to the rotation of the screw rod. The adjustment range of the height of the bedplate 35 can be selected according to the actual model, and under the condition that other conditions are not changed, the length of the screw rod and the length of the limiting hole 2a only need to be changed. And the position of the first limit screw 17 is modified correspondingly. Particularly, when the position of the bedplate 35 is raised, the gravity center of the machine rises, under the action of the unbalanced inertia force of the machine, the vibration of the bedplate 35 and the machine is increased due to the lengthening of the acting force arm, when the condition occurs, the distance between the supporting foot components 11 on the front side and the rear side can be increased by combining the distance adjusting mechanism of the supporting foot components 11, and the specific distance increased can be tested in advance according to different machine types. Due to the combination with the spacing adjustable mechanism of the supporting foot assembly 11, the problem of vibration increase of the other structure only with the bedplate 35 in the lifting bedplate 35 is avoided.

As shown in fig. 2 and 5, the upper transmission shaft 9 is composed of two sections, inner ends of the two sections of upper transmission shafts 9 are connected through an upper connecting shaft sleeve 18, outer ends of the two sections of upper transmission shafts 9 are respectively provided with a helical gear 16, and the two helical gears 16 respectively correspond to the screw rods 13 on the two side columns 2; the lower transmission shaft 6 is also composed of two sections, the inner ends of the two sections of lower transmission shafts 6 are connected through a lower shaft sleeve 19, the outer ends of the two sections of lower transmission shafts 6 are respectively provided with a meshing gear 5, and the two meshing gears 5 respectively correspond to the upper rack 3a and the lower rack 4a on the bases 1 at the two sides. The upper transmission shaft 9 simultaneously drives the two bevel gears 16 to rotate, so that the screw rods 13 on the upright posts 2 on the two sides are synchronously driven to rotate, the synchronous lifting adjustment of the lifting pillars 7 on the left side and the right side is realized, and the bedplate 35 is driven to stably lift; the lower transmission shaft 6 drives the meshing gears 5 at the two ends to rotate simultaneously, so that the synchronous adjustment of the distance between the four supporting foot components 11 is realized. A first belt pulley 20 and a second belt pulley 21 are respectively sleeved on the driving shaft 10, the driving shaft 10 can move axially, a clamping protrusion 10a in a multi-pyramid shape is arranged between the first belt pulley 20 and the second belt pulley 21 on the driving shaft 10, and clamping grooves 22 matched with the clamping protrusion 10a are formed in opposite sides of the first belt pulley 20 and the second belt pulley 21; when the driving shaft 10 moves axially, the clamping protrusions 10a can form clamping circumferential limit with the two clamping grooves 22 respectively; a third belt pulley 23 is fixedly arranged on the upper transmission shaft 9 of one section, a first transmission belt 25 is sleeved on the first belt pulley 20 and the third belt pulley 23, a fourth belt pulley 24 is fixedly arranged on the lower transmission shaft 6 of one section, and a second transmission belt 26 is sleeved on the second belt pulley 21 and the fourth belt pulley 24. When the driving shaft 10 drives the first belt pulley 20 to rotate clockwise, the rotation of the first belt pulley 20 realizes the clockwise rotation of the third belt pulley 23 through the first transmission belt 25, at the same time, the upper transmission shaft 9 fixed with the third belt pulley 23 and the bevel gear 16 on the upper transmission shaft 9 also rotate clockwise, the bevel gear 15 on the lead screw 13 is meshed with the bevel gear 16, and when viewed from top to bottom, the bevel gear 15 also rotates clockwise, and further the lead screw 13 fixedly connected with the bevel gear 15 also rotates clockwise, the two bearing seats 12 are fixed on the upright post 2, the function of the lifting device is to support a lead screw 13, a nut slide block 14 is fixed on the lifting support 7 and meshed with the lead screw 13, when the screw 13 rotates clockwise, the screw sliding block 14 engaged with the screw moves downwards along with the screw, so that the lifting support 7 is driven to move downwards, and the bedplate 35 is lowered; according to the same principle, the screw rod 13 on the other side rotates rightwards and rotates anticlockwise to synchronously drive the lifting support 7 on the other side to move downwards so as to realize the downward movement of the bedplate 35. To raise the platen 35, the drive shaft 10 is simply rotated counterclockwise about the first pulley 20. The second belt pulley 21 and the fourth belt pulley 24 are connected through a second transmission belt 26, when the driving shaft 10 rotates anticlockwise, the second transmission belt 26 synchronously rotates in the same direction, and the fourth belt pulley 24 is fixed on one section of the lower transmission shaft 6 through two tacking screws. The rotation of the belt pulley four 24 drives the lower transmission shaft 6 and the meshing gear 5 on the lower transmission shaft 6 to rotate, the upper rack 3a on the upper support tube 3 and the lower rack 4a on the lower support tube 4 are meshed with the meshing gear 5 simultaneously, when the meshing gear 5 rotates anticlockwise, the upper rack 3a on the upper support tube 3 and the lower rack 4a on the lower support tube 4 respectively move forwards and backwards in a straight line, and the distance between the support leg assembly 11 on the upper support tube 3 and the support leg assembly 11 on the lower support tube 4 is more and more far away. Similarly, when the distance between the supporting leg assemblies 11 at the front and rear sides is required to be reduced, the meshing gear 5 is only required to rotate clockwise.

In the gear rack structure, the front and rear supporting leg assemblies 11 move back and forth according to the distance of 1:1, and when the same gear is changed into a double gear, the module and the number of teeth of the gear are changed, so that the front and rear supporting leg assemblies 11 can move according to a required proportion. The number of the upper supporting tubes 3 and the number of the lower supporting tubes 4 are respectively 2, and according to actual requirements, only the front 2 lower supporting tubes 4 or the rear 2 upper supporting tubes 3 can be reserved, and other mechanisms can be unchanged.

In this embodiment, the supporting base 27 is fixedly arranged on the upright post 2, two bearings 28 with seats are arranged on the supporting base 27 at intervals, and the first belt pulley 20 and the second belt pulley 21 are respectively arranged on the two bearings 28 with seats; a connecting sleeve 29 is fixedly arranged at one end of the driving shaft 10, and a gear shifting connecting rod 30 is axially fixed and circumferentially rotatably sleeved on the connecting sleeve 29; a through hole 27a is formed in the supporting seat 27, a partition plate 27b which divides the lower part of the through hole 27a into two clamping grooves 27c is arranged on the lower side of the through hole 27a, and the outer end of the gear shifting connecting rod 30 can be clamped in the clamping grooves 27 c; a pre-tightening spring 31 is sleeved on the driving shaft 10 between the bearing 28 with the seat and the connecting sleeve 29. In view of space limitation and manufacturing cost, the invention only uses one set of driving mechanism to realize the rotation of the two mechanisms, the pulley I20 and the pulley II 21 are respectively arranged on the two belt seat bearings 28, in order to prevent the axial movement of the pulley I20 and the pulley II 21, shaft end snap springs are arranged at the shaft ends of the pulley I20 and the pulley II 21, the driving shaft 10 simultaneously passes through the pulley I20 and the pulley II 21 and is in clearance fit with the pulley I and the pulley II, a pre-tightening spring 31 is arranged on the driving shaft 10 and is arranged between the connecting sleeve 29 and the belt seat bearings 28 and is contacted with the end surfaces of the connecting sleeve 29 and the connecting sleeve 29 is fixed on the driving shaft 10, a shifting connecting rod 30 is arranged on the connecting sleeve 29 and is in clearance fit with the connecting sleeve 29, and the shifting connecting rod 30 can rotate 360 degrees around the connecting sleeve 29. When the gear shifting connecting rod 30 is respectively positioned in the two clamping grooves 27c, the end face of the gear shifting connecting rod 30 can be tightly attached to the clamping groove face of the clamping groove 27c due to the existence of the pre-tightening spring 31, and the position of the gear shifting connecting rod is ensured not to shake due to vibration of the sewing machine. During gear shifting, only the gear shifting connecting rod 30 needs to be manually rotated to a proper angle, the axial force acting on the driving shaft 10 is loosened, the driving shaft 10 can automatically axially move for a distance under the action of the pre-tightening spring 31, and only two gears are switched by the device, so the pre-tightening force of the pre-tightening spring 31 can directly push the driving shaft 10 to another proper gear position, then the gear shifting connecting rod 30 is manually and rotatably placed in another clamping groove 27c, and then the movement of spacing adjustment of the supporting foot components 11 and lifting adjustment of the bedplate 35 can be realized only by rotating the driving shaft 10. Similarly, an inward pressure is applied to the driving shaft 10, and then the shift link 30 is rotated to the other catching groove 27 c. Since the driving shaft 10 needs to be switched between and maintain good engagement with the pulley one 20 and the pulley two 21, and since the two mechanisms are operated separately, the angle between the pulley one 20 and the pulley two 21 is certainly different, and the driving shaft can be designed to have a tapered hexahedral structure having good alignment, which ensures that the engagement groove 22 of 60 degrees is automatically aligned when the engagement protrusion 10a of the driving shaft 10 is brought into contact with the pulley one 20 or the pulley two 21 due to the presence of the taper regardless of the angle difference between the pulley one 20 and the pulley two 21, thereby achieving the engagement of the driving shaft 10 with the pulley one 20 or the pulley two 21.

In this embodiment, the second limit screw 32 is screwed on the upper side of the base 1, the upper rack 3a is provided with a strip-shaped hole 3a1 along the length direction thereof, and the second limit screw 32 is movably inserted into the strip-shaped hole 3a 1. The main function of the second limit screw 32 is to prevent the upper rack 3a and the lower rack 4a from moving excessively when rotating in mesh with the meshing gear 5, so that the upper rack and the lower rack are disengaged from the meshing gear 5 or the upper support tube 3 and the lower support tube 4 collide with each other.

As shown in fig. 6, the supporting foot assembly 11 of this embodiment comprises a mounting frame 11c, a caster 11a is rotatably connected to the mounting frame 11c through a rotating bracket 11d, an adjusting screw 11e and a lock nut 11f are mounted on the rotating bracket 11d at one side of the caster 11a, and a foot cup 11b is ball-hinged at the lower end of the adjusting screw 11 e. The height of the caster 11a is fixed and can not be adjusted, while the height of the foot cup 11b can be adjusted by screwing the adjusting screw 11e and the locking nut 11f with a wrench, and the bottom surface of the foot cup 11b can be higher or lower than the lowest point of the bottom surface of the caster 11a according to different working conditions. Preferably, the caster 11a is a universal wheel, and the rotating bracket 11d is rotatably connected to the mounting bracket 11c, so that the caster 11a can rotate 360 degrees to facilitate movement; the foot cup 11b is in spherical hinge connection with the adjusting screw rod 11e, so that the foot cup 11b can generate a certain inclination, and the stand can also keep stable on uneven ground; the height of the adjusting screw 11e can be adjusted by the arrangement of the adjusting screw 11e and the locking nut 11f, so that the height of the supporting foot assembly 11 can be adjusted according to actual conditions, and the caster 11a or the foot cup 11b can be selected according to actual requirements.

In this embodiment, the driving shaft 10 is connected with a driving motor or a driving handle; two bases 1 all are square tubular and both parallel interval settings, have linked firmly the connecting plate 33 that is used for installing the running-board between two bases 1, have linked firmly between two stands 2 and have strengthened longeron 34. Therefore, the pedal can be conveniently installed, and the stability and the reliability of the installation are improved. In the embodiment, the driving of the driving shaft 10 can be manual or electric, and for manual operation, only a driving handle such as a hand wrench is added at the end part of the driving shaft 10; if the driving shaft 10 needs to be changed into an electric driving shaft, a small change needs to be made on the existing structure, namely, a similar air cylinder is added in the axial direction of the driving shaft 10 to realize the switching of the axial gear of the driving shaft 10, and then a set of servo motor is added to realize the axial rotation of the driving shaft 10.

The specific embodiments described herein are merely illustrative of the spirit of the invention. Various modifications or additions may be made to the described embodiments or alternatives may be employed by those skilled in the art without departing from the spirit or ambit of the invention as defined in the appended claims.

Although more use is made herein of 1, a base; 2. a column; 2a, limiting holes; 3. an upper support tube; 3a, an upper rack; 3a1, strip shaped holes; 4. a lower support tube; 4a, a lower rack; 5. a meshing gear; 6. a lower transmission shaft; 7. a lifting column; 8. a support pallet; 9. an upper transmission shaft; 10. a drive shaft; 10a, clamping protrusions; 11. a support leg assembly; 11a, a caster; 11b, a foot cup; 11c, a mounting rack; 11d, rotating the bracket; 11e, adjusting the screw rod; 11f, locking the nut; 12. a bearing seat; 13. a lead screw; 14. a nut slide block; 15. a bevel gear; 16. a helical gear; 17. a first limit screw; 18. an upper connecting shaft sleeve; 19. the lower shaft sleeve is connected; 20. a first belt pulley; 21. a second belt pulley; 22. a clamping groove; 23. a third belt pulley; 24. a belt pulley IV; 25. a first transmission belt; 26. a second transmission belt; 27. a supporting seat; 27a, a through hole; 27b, a partition plate; 27c, a clamping groove; 28. a pedestal bearing; 29. connecting sleeves; 30. a shift link; 31. pre-tightening the spring; 32. a second limit screw; 33. a connecting plate; 34. stiffening stringers, etc., but does not exclude the possibility of using other terms. These terms are used merely to more conveniently describe and explain the nature of the present invention; they are to be construed as being without limitation to any one of the additional limitations that fall within the spirit of the present invention.

Claims

1. A frame of a sewing machine comprises two tubular bases (1) which are longitudinally arranged at intervals, wherein an upright post (2) is vertically and fixedly arranged on each base (1), and the frame is characterized in that an upper supporting tube (3) and a lower supporting tube (4) are movably inserted into two ends of each base (1) respectively, a lower rack (4a) extending towards the inside of the base (1) is arranged on the lower side of the lower supporting tube (4), and an upper rack (3a) extending towards the inside of the base (1) is arranged on the upper side of the upper supporting tube (3); the upper rack (3a) and the lower rack (4a) are arranged oppositely, a meshing gear (5) capable of driving the upper rack (3a) and the lower rack (4a) to move longitudinally is arranged between the upper rack and the lower rack, and a lower transmission shaft (6) is connected to the meshing gear (5); each upright post (2) is provided with a vertical lifting support post (7) in a sliding manner, the upper end of each lifting support post (7) is provided with a supporting plate (8), and an upper transmission shaft (9) capable of driving the lifting support posts (7) to move up and down is arranged below each lifting support post (7); the upright post (2) is also provided with a driving shaft (10) which can drive the upper transmission shaft (9) and the lower transmission shaft (6) to rotate; supporting leg assemblies (11) with casters (11a) are mounted at the bottoms of the outer ends of the upper supporting tube (3) and the lower supporting tube (4).

2. The frame of the sewing machine according to claim 1, characterized in that a bearing seat (12) is fixedly arranged on the side surface of the upright post (2) at intervals from top to bottom, a bearing is arranged in the bearing seat (12), and a vertical lead screw (13) is inserted in the two bearings; the side surface of the lifting support column (7) is fixedly provided with a screw nut sliding block (14), the screw nut sliding block (14) is in threaded connection with the screw rod (13), the lower end of the screw rod (13) is fixedly provided with a bevel gear (15), and the end part of the upper transmission shaft (9) is fixedly provided with a bevel gear (16) meshed with the bevel gear (15).

3. The frame of the sewing machine according to claim 2, characterized in that the side surface of the upright post (2) is provided with a long strip-shaped limiting hole (2a), the length direction of the limiting hole (2a) is vertically arranged, and a first limiting screw (17) is inserted into the limiting hole (2 a).

4. The frame of the sewing machine according to claim 3, characterized in that the upper transmission shaft (9) is composed of two sections, the inner ends of the two sections of the upper transmission shaft (9) are connected through an upper connecting shaft sleeve (18), the outer ends of the two sections of the upper transmission shaft (9) are respectively provided with a bevel gear (16), and the two bevel gears (16) respectively correspond to the screw rods (13) on the two side upright posts (2); the lower transmission shaft (6) is also composed of two sections, the inner ends of the two sections of lower transmission shafts (6) are connected through a lower shaft sleeve (19), the outer ends of the two sections of lower transmission shafts (6) are respectively provided with an engaging gear (5), and the two engaging gears (5) respectively correspond to the upper rack (3a) and the lower rack (4a) on the bases (1) on the two sides.

5. The frame of the sewing machine according to claim 4, wherein a first belt pulley (20) and a second belt pulley (21) are respectively sleeved on the driving shaft (10), the driving shaft (10) can move axially, a clamping protrusion (10a) in a multi-pyramid shape is arranged on the driving shaft (10) and located between the first belt pulley (20) and the second belt pulley (21), and clamping grooves (22) matched with the clamping protrusion (10a) are formed in opposite sides of the first belt pulley (20) and the second belt pulley (21); when the driving shaft (10) moves axially, the clamping protrusions (10a) can form clamping circumferential limit with the two clamping grooves (22) respectively; one section of the transmission shaft (9) is fixedly provided with a third belt pulley (23), the first belt pulley (20) and the third belt pulley (23) are sleeved with a first transmission belt (25), one section of the transmission shaft is fixedly provided with a fourth belt pulley (24) on the lower transmission shaft (6), and the second belt pulley (21) and the fourth belt pulley (24) are sleeved with a second transmission belt (26).

6. A frame for a sewing machine according to claim 5, characterized in that the upright (2) is fixedly provided with a support (27), the support (27) is provided with two bearings (28) with seats at intervals, and the first belt pulley (20) and the second belt pulley (21) are respectively arranged on the two bearings (28) with seats; a connecting sleeve (29) is fixedly arranged at one end of the driving shaft (10), and a gear shifting connecting rod (30) is axially fixed on the connecting sleeve (29) and circumferentially rotatably sleeved on the connecting sleeve (29); a through hole (27a) is formed in the supporting seat (27), a partition plate (27b) which divides the lower portion of the through hole (27a) into two clamping grooves (27c) is arranged on the lower side of the through hole (27a), and the outer end of the gear shifting connecting rod (30) can be clamped in the clamping grooves (27 c); and a pre-tightening spring (31) is sleeved between the bearing with a seat (28) and the connecting sleeve (29) on the driving shaft (10).

7. The frame of the sewing machine according to any one of claims 1 to 6, characterized in that a second limit screw (32) is screwed on the upper side of the base (1), a strip-shaped hole (3a1) is formed in the upper rack (3a) along the length direction of the upper rack, and the second limit screw (32) is movably inserted into the strip-shaped hole (3a 1).

8. Sewing machine frame according to any one of claims 1-6, characterized in that said supporting foot assembly (11) further comprises a mounting frame (11c) and a foot cup (11b), said castor (11a) being rotatably connected to said mounting frame (11c) by means of a rotating bracket (11d), said rotating bracket (11d) being provided with an adjusting screw (11e) and a locking nut (11f) on one side of said castor (11a), said foot cup (11b) being ball-hinged to the lower end of said adjusting screw (11 e).

9. Sewing machine frame as in any claim from 1 to 6, characterized in that said drive shaft (10) is connected to a drive motor or drive handle; the two bases (1) are both in a square tubular shape and are arranged in parallel at intervals, a connecting plate (33) used for mounting a pedal is fixedly connected between the two bases (1), and a reinforcing longitudinal beam (34) is fixedly connected between the two upright columns (2).