CN208598226U - A kind of food processing machine transmission connecting structure and food processor - Google Patents

Abstract

The utility model discloses a kind of food processing machine transmission connecting structure and food processor, the transmission connecting structure includes driving link and driven member, the end face of the driving link is equipped with mating groove, the driven member is equipped with the auxiliary section opposite with mating groove, the auxiliary section stretches in mating groove, realize the transmission connection of driving link and driven member, the driving link is equipped with guide frame on the end face around mating groove, the guide frame guides auxiliary section to mating groove, the guide frame includes multiple convex ribs around mating groove setting, it can be realized automatic rapid alignment, improve installation portability.

Description

A kind of food processing machine transmission connecting structure and food processor

Technical field

The utility model relates to field of food processing machines, more particularly, to a kind of food processing machine transmission connecting structure and Food processor.

Background technique

Existing food processor, such as cooking machine, juice extractor, flour stranding machine and meat grinder, generally include in set motor Host and processing assembly, motor communicate rotational motion to processing assembly by transmission connecting structure, and processing assembly rotation is stirred Mix the intracorporal food materials of cup.

Existing transmission connection component includes driving link and driven member, and driving link is mounted on motor, and driven member is mounted on In the rotary shaft of processing assembly, driving link and driven member alignment are clasped, and realize that driving link drives driven member rotation.But When host is installed on processing assembly, driving link and driven member generally can not rapid alignment or even driving link and driven member be There is the phenomenon that mutual dieback, be also hardly visible and whether be aligned after installation, is not easy to operate.

Utility model content

The utility model proposes a kind of food processing machine transmission connecting structure and food processor, can be realized automatic fast Speed alignment improves installation portability.

The utility model provides a kind of transmission connecting structure, including driving link and driven member, on the end face of the driving link Equipped with mating groove, the driven member is equipped with the auxiliary section opposite with mating groove, and the auxiliary section stretches in mating groove, realizes The transmission connection of driving link and driven member, the driving link are equipped with guide frame, the guiding on the end face around mating groove Structure guides auxiliary section to mating groove, and the guide frame includes multiple convex ribs around mating groove setting.

Preferably, the mating groove include be arranged in the first mating groove in the middle part of driving link, from the first mating groove periphery to Multiple second mating grooves of outer extension, multiple second mating grooves are provided at circumferentially spaced, and convex ribs are set to two neighboring second Between mating groove.

Preferably, the inclined surface that the convex ribs have arcuate end and are extended from arcuate end towards two sides, institute Inclined surface and the edge of the second mating groove is stated to abut against.

Preferably, the auxiliary section includes the convex block that protrusion is arranged on driven member side wall, and the convex block extends to driven The end face of part, the convex block and the second mating groove clearance fit.

Preferably, the driven member has a bearing surface with driving link opposite side, and the area of the bearing surface is less than the The area of one mating groove.

Preferably, the end face of the driving link has been recessed arc-shaped depression portion, and the opposite one end fits of the driven member are stretched Enter to arc-shaped depression portion, the mating groove and guide frame are arranged in the arc-shaped depression portion.

Preferably, the arc-shaped depression portion has arcwall face, is putting down vertically using any point on the arcwall face edge as starting point The tangent line of the arcwall face is made in face, forms included angle A between the tangent line and horizontal plane, 10 °≤A≤80 °.

Preferably, the end face protrusion of the driven member is arc-shaped, is starting point vertical using the end face edge of the driven member The tangent line of the end face is made in plane, forms included angle B between the tangent line and horizontal plane, 30 °≤B≤60 °.

The utility model also provides a kind of food processor, including the host with motor, the processing that is arranged on host Component is provided with transmission connecting structure described above, the rotation of the motor between the motor shaft and processing assembly of the motor Rotatory force is transferred to processing assembly by the transmission connecting structure.

Preferably, the food processor is cooking machine or meat grinder, and the processing assembly includes that cup body and setting exist The intracorporal stirring blade of cup, the stirring blade have rotary shaft, the transmission connection are provided between the motor shaft and rotary shaft Structure；Alternatively, the food processor is juice extractor, the processing assembly includes cup body and screw rod arranged in cup body, The transmission connecting structure is provided between the motor shaft and screw rod；Alternatively, the food processor is flour stranding machine, it is described to add Work component includes stirring face cylinder and the flour-stirring rod stirred in the cylinder of face being arranged in, and the biography is provided between the flour-stirring rod and motor shaft Dynamic connection structure.

The utility model has the following beneficial effects:

1, the utility model provides one kind and is used for food processing machine transmission connecting structure, including driving link and driven member, The end face of the driving link is equipped with mating groove, and the driven member is equipped with the auxiliary section opposite with mating groove, and the auxiliary section is stretched Enter to the transmission connection of realization driving link and driven member in mating groove, the driving link is equipped on the end face around mating groove and leads To structure, the guide frame guides auxiliary section to mating groove, and the guide frame includes multiple around mating groove setting Convex ribs, convex ribs can be realized the Fast Installation of driving link and driven member, be not necessarily to manual manual correction, quick and easy for installation, use Family experience is high, and avoids manual alignment and correct brought maloperation, operates safer.

2, by the way that guide frame is arranged on the end face around mating groove, the mating groove includes being arranged in the middle part of driving link The first mating groove, from outwardly extending multiple second mating grooves of the first mating groove periphery, multiple second mating grooves are circumferential Interval setting, convex ribs are set between two neighboring second mating groove, and the convex ribs have arcuate end and from arcuate end The inclined surface being extended towards two sides, the inclined surface and the edge of the second mating groove abut against, if in this way driving link and from When moving part is not aligned with, the end face of the driven member convex block is in contact with the arcuate end of convex ribs, and arcuate end and inclined surface are matched Conjunction guides convex block to the second mating groove, which enables to driving link and driven member to realize automatic aligning, so that Driving link and the cooperation of driven member Rapid fastener, are not necessarily to manual manual correction, quick and easy for installation, and the guide frame structure letter Single, processing stability is high, and guiding stability is high, and the second mating groove is distributed with multiple in the circumferential, and such convex block and second can It is easy to operate to be cooperated with multiple angles.

3, by the way that driven member to be had to the bearing surface with driving link opposite side, the area of the bearing surface is matched less than first The area of slot is closed, dieback when can install in this way to avoid driving link and driven member inclination improves cooperation precision, also reduces processing Difficulty reduces processing cost.

4, the end face of the driving link has been recessed arc-shaped depression portion, and the opposite one end protrusion of the driven member is arc-shaped, Cooperate the arc protruding end of driven member to stretch in arc-shaped depression portion, can guide in driving link and driven member in this way Heart alignment increases the goodness of fit that driving link and driven member are clasped, avoids the vibration that food processor starts or work generates Cause driving link and driven member to separate, improves transmission stability, avoid the reduction of transmission efficiency.

5, the driving link arc-shaped depression portion is equipped with arcwall face, by existing using any point on the arcwall face edge as starting point The tangent line of the arcwall face is made in perpendicular, forms included angle A between the tangent line and horizontal plane, 10 °≤A≤80 °, if When included angle A is greater than 80 °, the face area of the second mating groove reduces, and effective engagement area of the second mating groove reduces, if to protect The diameter of driving link must be increased by demonstrate,proving same engagement area, will lead to the transfer of driving link and driven member in this way, reduce transmission Efficiency；If included angle A is less than 10 °, the depth of the arc-shaped depression portion is smaller, and the intensity after driving link and driven member cooperation is poor, It is easy to cause driving link and driven member to be detached from by vibration in this way, it can be preferable between the end face of driving link and the end face of driven member Guiding cooperation, and the engagement area of driving link and driven member is larger, joggled strength is stronger, and transmission efficiency is relatively stable, and described Guide frame radical length is moderate, can preferably guide to the second mating groove convex block, will not make because of guide frame mistake Length causes convex block radially to slide, or convex block will not be caused stuck because guide frame is too short.

6, the end face protrusion of the driven member is arc-shaped, to cooperate with the first mating groove.With the driven member End face edge is the tangent line L2 that starting point makes the end face in perpendicular, forms angle between the tangent line L2 and horizontal plane B, 30 °≤B≤60 °, under the angular range, the end face of the driven member is had better guiding function, and will not cause to nibble It is too small to close area, so that the end face of driven member and the first mating groove rapid alignment, when included angle B is greater than 60 °, driven member Guide effect is poor, and effective engagement area of convex block is smaller, and the difficulty of processing of the driven member is larger, and processing cost is higher, when Included angle B is less than 30 °, and the cooperation intensity of driving link and driven member is smaller, and driving link and driven member are easily separated from.

Detailed description of the invention

In order to illustrate the embodiment of the utility model or the technical proposal in the existing technology more clearly, below will be to embodiment Or attached drawing needed to be used in the description of the prior art is briefly described, it should be apparent that, the accompanying drawings in the following description is only It is some embodiments of the utility model, for those of ordinary skill in the art, before not making the creative labor property It puts, is also possible to obtain other drawings based on these drawings.

Fig. 1 is the stereogram exploded view of the utility model food processor.

Fig. 2 is the cross-sectional view of the utility model food processor.

Fig. 3 is the stereogram exploded view of the utility model food processing machine host.

Fig. 4 is the perspective view of the utility model food processing machine host.

Fig. 5 is the top view of the utility model food processor cup cover.

Fig. 6 is the utility model transmission connecting structure main view.

Fig. 7 is the perspective view of the utility model transmission connecting structure driving link.

Fig. 8 is the perspective view of the utility model transmission connecting structure driven member.

Fig. 9 is the bottom view of the utility model stirring blade rotary shaft.

Figure 10 is the perspective view of the utility model locating shaft.

Wherein: 1 host, 2 processing assemblies, 3 transmission connecting structures, 4 safety switches, 11 pedestals, 12 host main bodys, 13 decorations Part, 14 lids, 15 motors, 16 control panels, 18 positioning bars, 19 boss, 21 cup bodies, 211 locating shafts, 22 cup lids, 23 stirring blades, 231 rotary shafts, 232 blades, 2311 hollow cavities, 222 abutting portions, 223 accommodating cavities, 224 mating cavities, 225 locating pieces, 191 first Limiting section, 192 second limiting sections, 193 limiting slots, 41 contradict head, and 181 resigning recess portions, 31 driving links, 32 driven members, 311 match Conjunction slot, 312 arc-shaped depression portions, 321 auxiliary sections, 221 through-holes, 231 rotary shafts, 2311 hollow cavities, 3,111 first mating grooves, 3112 Second mating groove, 33 guide frames, 331 convex ribs, 3311 arcuate ends, 3312 inclined surface, 3211 ontologies, 3212 convex blocks, 5 stop Bassinet structure, 51 first buckle muscle, 52 buckle slots, 53 second buckle muscle, 54 elastic reset structures, 541 expansion plates, 542 springs.

Specific embodiment

The following will be combined with the drawings in the embodiments of the present invention, carries out the technical scheme in the embodiment of the utility model Clearly and completely describe, it is clear that the described embodiments are only a part of the embodiments of the utility model, rather than whole Embodiment.Based on the embodiments of the present invention, those of ordinary skill in the art are without creative efforts Every other embodiment obtained, fall within the protection scope of the utility model.

It is to be appreciated that following "upper", "lower", "left", "right", " longitudinal direction ", " transverse direction ", "inner", "outside", " perpendicular Directly ", the indicating positions such as "horizontal", "top", "bottom" or the word of positional relationship are based only upon orientation or positional relationship shown in the drawings, Only for the purposes of describing the utility model and simplifying description, rather than device/element of indication or suggestion meaning must have spy Fixed orientation is constructed and operated in a specific orientation, therefore should not be understood as limiting the present invention.

- Figure 10 referring to Figure 1 the utility model relates to a kind of food processor, including host 1, processing assembly 2 and is set The transmission connecting structure 3 between host 1 and processing assembly 2 is set, the host 1 includes pedestal 11, is arranged on the pedestal 11 Host main body 12, the decoration 13 being set in host main body 12 and the lid 14 being arranged on decoration, the pedestal 11 It is fastenedly connected with host main body, the upper end of the pedestal is equipped with first step portion (not labeled), and the lower end of the lid is equipped with the Two stage portion (not labeled), the first step portion and the cooperation of second step portion compress the decoration 13, the host main body There is in 12 motor 15 and control panel 16, the pedestal 11 is connected with host main body 12 by a fastener, the fastener from Under be upward through pedestal 11 and host main body 12.The material of the decoration is stainless steel, has the advantages that appearance beauty, Product specification is also greatly promoted simultaneously.In the present embodiment, the food processor is meat grinder, and the processing assembly is stirring Cup assembly, the fastener are fastening screw.

The processing assembly 2 includes cup body 21, cup lid 22 and the stirring blade 23 being arranged in cup body 21, the host 1 It is mounted on cup lid 22.The stirring blade 23 includes rotary shaft 231 and two groups of blades 232 being arranged in rotary shaft 231, and two Group blade 232 is axially setting up and down along rotary shaft, and the blade positioned at upside is obliquely installed in the horizontal plane, the blade positioned at downside It is horizontally disposed, the food materials of different height can be crushed from different perspectives in this way.The rotary shaft 231 has hollow cavity 2311, institute State that 21 bottom of cup body is protruding upward to be provided with locating shaft 211, the cooperation of locating shaft 211 stretches in hollow cavity 2311 and can It is moved axially in hollow cavity 2311.

Accommodating cavity 223 is recessed in the top of the cup lid 22,1 bottom of the host protrusion is equipped with circular orientation muscle 18, The cooperation of positioning bar 18 stretches in accommodating cavity 223, and the accommodating cavity has the side bottom of chamber Mian Heqiang, positioning bar 18 and accommodating The chamber side of chamber is in contact, and to realize the centralized positioning of host and cup lid, is convenient for Fast Installation.The bottom of chamber face is equipped with annular Abutting portion 222, the cup lid 22 have the mating cavity 224 for being located at 222 inside of abutting portion, the master of 18 inside of positioning bar Motor spindle is downwardly projecting to be equipped with boss 19, and the boss 19 protrudes out in mating cavity 224.

The side wall of the boss 19 is outwardly protruded equipped with the first limiting section 191, the master in the outside of first limiting section 191 Motor spindle is equipped with the second limiting section 192, is formed with limiting slot 193 between first limiting section 191 and the second limiting section 192, Safety switch 4 is provided in the limiting slot 193.The safety switch 4 is electrically connected with control panel 12.The safety switch 4 has Head 41 is contradicted, the conflict head 41 protrudes the host lower surface setting.22 top of cup lid is protruding upward to be supported equipped with annular Contact portion 222, when the host 1 is installed to cup lid 22, the abutting portion 222 with conflict head 41 by contacting, to trigger safety open 4 are closed, in a ring due to the abutting portion, no matter host is in contact with what angle with head is contradicted, and can be stablized with safety switch Ground contact, and it is quick and easy for installation.The limiting slot is to limit annular collision parts, so that annular collision parts are in above-below direction Upper inconsistent with conflict, avoiding abutting portion from contradicting head from lateral press causes to contradict head damage, or poor contact occurs Situation.

It is additionally provided with locating piece 225 on the bottom of chamber face in 222 outside of abutting portion, the positioning bar 18 is equipped with resigning recess portion 181, the resigning recess portion 181 is the arc resigning muscle of the radial recessed formation of self-positioning muscle 18, and the locating piece 225 protrudes into cooperation To resigning recess portion 181, meanwhile, fastener hole is equipped on the inside of the resigning recess portion 181, the fastener is arranged at fastener hole simultaneously Lock the lid 14 upwards, such resigning recess portion can either carry out angle of the positioning host on cup lid as block reinforcement, and can be with Guidance fastener enters in fastener hole.

The transmission connecting structure 3 includes driving link 31 and driven member 32, and the end face of the driving link 31 has been recessed Arc-shaped depression portion 312, the arc-shaped depression portion have arcwall face, and the arcwall face is equipped with mating groove 311, on the driven member 32 Equipped with the auxiliary section 321 opposite with mating groove 311, the auxiliary section 321 is stretched in mating groove 311, realize driving link with from The transmission connection of moving part.The cup lid 22 is equipped with through-hole 221, and the rotary shaft 231 is upward through the through-hole 221, described Rotary shaft 231 has hollow cavity 2311, and the driven member 32 is embedded in the hollow cavity 2311 of 231 one end of rotary shaft.It can manage Xie Di, the driven member passes through the through-hole 221, and snaps connection with driving link.

The mating groove 311 includes the first mating groove 3111 that the middle part of driving link 31 is arranged in, from the first mating groove 3111 Outwardly extending multiple second mating grooves 3112 of periphery, multiple second mating grooves 3112 are provided at circumferentially spaced.The active Part 31 is equipped with guide frame 33 on the arcwall face around mating groove 311, and the guide frame includes setting two neighboring the Convex ribs 331 between two mating grooves 3112.The convex ribs 331 have arcuate end 3311 and from 3311 directions of arcuate end The extended inclined surface 3312 in two sides, the inclined surface 3312 and the edge of the second mating groove 3112 abut against.In this implementation In example, the mating groove is spline.

The auxiliary section 321 includes ontology 3211, protrudes the convex block 3212 being arranged on 3211 side wall of ontology, the convex block 3212 extend to the end face of driven member, the ontology 3211 and the first mating groove clearance fit, and the convex block 3212 is matched with second 3112 clearance fit of slot is closed, when installation, when convex block 3212 is not aligned with the second mating groove 3112, e.g., convex block 3212 and convex ribs 331 is inconsistent, due on convex ribs 331 arcuate end 3311 and inclined surface 3312 convex block 3212 can be guided to described second In mating groove 3112, to realize that the Rapid fastener of driving link 31 and driven member 32 cooperates, it is not necessarily to manual manual correction, installation side Just quick.In the present embodiment, the inclined surface is plane, it is possible to understand that ground, the inclined surface may be the arc of convex Face, or the cambered surface to concave reduce coefficient of friction swimmingly to guide convex block to enter in the second mating groove, reduce abrasion, mention The service life of high transmission connecting structure.

The contact position of the inclined surface and the second mating groove is equipped with the cambered surface to set to the concave, can discharge stress in this way, It avoids stress from concentrating cracking, improves usable floor area.

Make the tangent line L1 of the arcwall face in perpendicular using any point on the arcwall face edge as starting point, it is described Form included angle A between tangent line L1 and horizontal plane, 10 °≤A≤80 °, under the angular range, the end face of driving link and driven member Cooperation can be preferably oriented between end face, and the engagement area of driving link and driven member is larger, joggled strength is stronger, transmission effect Rate is relatively stable, and the guide frame radical length is moderate, can preferably guide convex block 3212 to the second mating groove It in 3112, will not to cause convex block radially to slide because guide frame is too long, or will not cause because guide frame is too short convex Block is stuck.

The end face protrusion of the driven member 32 is arc-shaped, to cooperate with the first mating groove 3111.With described driven The end face edge of part 32 is the tangent line L2 that starting point makes the end face in perpendicular, shape between the tangent line L2 and horizontal plane At included angle B, 30 °≤B≤60 °, under the angular range, the end face of the driven member is had better guiding function, will not Cause engagement area too small, so that the end face of driven member 32 and 3111 rapid alignment of the first mating groove.

The end face of the driven member is equipped with bearing surface 322, and the bearing surface 322 is plane and area is less than driven member Cross-sectional area, and it is opposite with first mating groove, the area of the bearing surface in this way may be used less than the area of the first mating groove To play preferable guiding role.It is to be appreciated that can also be without bearing surface, i.e., the described driven member on the end face of the driven member End face be protrusion arc, the center rapid alignment of driving link and driven member can be made in this way.

The food processor also has brake structure 5, and the brake structure 5 is more on hollow cavity side wall including being arranged in It is a first buckle muscle 51 and be arranged at the top of rotary shaft second buckle muscle 53, it is described first buckle muscle from hollow cavity end to Interior to extend one section, multiple first buckle muscle, 51 annulars are arranged, and are formed with card between two adjacent first buckle muscle 51 Catching groove 52, multiple buckle slots form spline, and when installing stirring blade to locating shaft 211, the second buckle muscle 51 blocks In button to buckle slot, the rotation stop to rotary shaft is realized.

Elastic reset structure 54, the elastic reset structure 54 are provided in the hollow cavity of first buckle muscle, 51 upside Including expansion plate 541 and the spring being arranged on expansion plate 541 542, the upper end of the spring 542 and 32 phase of driven member Even, in the initial state, that is, when the rotary shaft is mounted on locating shaft by hollow cavity, the second buckle muscle is buckled in In buckle slot, at this point, rotary shaft can not rotate, the expansion plate 541 is in contact with the upper end of the first buckle muscle.When host 1 is pacified When on stirring cup, the gravity of host 1 pushes rotary shaft by transmission connecting structure 3, so that rotary shaft moves down, institute It states the second buckle muscle and is detached from buckle slot, and it is mobile to contradict expansion plate compressed spring 542, at this point, the rotary shaft is in rotation State.The brake structure can be avoided when being opened accidentally cup lid or idle running is uncapped, and stirring blade is transported since inertia continues high speed Then bring danger in 1.5s, it can be achieved that stall stirring blade, it is ensured that using safe.

It is to be appreciated that the guide frame may be the salient point being arranged between two neighboring second mating groove, it is convex The end of point is arc-shaped dotted.

It is to be appreciated that the food processor is juice extractor, the processing assembly includes cup body and is arranged in cup body Interior screw rod is provided with the transmission connecting structure between the motor shaft and screw rod.It is to be appreciated that the food processor For flour stranding machine, the processing assembly includes the flour-stirring rod for stirring face cylinder and being arranged in a face of stirring tin, the flour-stirring rod and motor shaft Between be provided with the transmission connecting structure.

The above is only the preferred embodiment of the utility model only, is not intended to limit the utility model, all at this Within the spirit and principle of utility model, any modification, equivalent replacement, improvement and so on should be included in the utility model Protection scope within.

Claims (10)

1. a kind of food processing machine transmission connecting structure, including driving link and driven member, the end face of the driving link are equipped with Mating groove, the driven member are equipped with the auxiliary section opposite with mating groove, and the auxiliary section stretches in mating groove, realize actively The transmission connection of part and driven member, it is characterised in that: the driving link is equipped with guide frame, institute on the end face around mating groove It states guide frame to guide auxiliary section to mating groove, the guide frame includes multiple convex ribs around mating groove setting.

2. transmission connecting structure according to claim 1, it is characterised in that: the mating groove includes being arranged in driving link First mating groove in portion, from outwardly extending multiple second mating grooves of the first mating groove periphery, multiple second mating grooves weeks It is arranged to interval, convex ribs are set between two neighboring second mating groove.

3. transmission connecting structure according to claim 2, it is characterised in that: the convex ribs have arcuate end and from arc The inclined surface that shape end is extended towards two sides, the inclined surface and the edge of the second mating groove abut against.

4. transmission connecting structure according to claim 2, it is characterised in that: the auxiliary section includes that protrusion is arranged driven Convex block on part side wall, the convex block extend to the end face of driven member, the convex block and the second mating groove clearance fit.

5. transmission connecting structure according to claim 2, it is characterised in that: the driven member has opposite with driving link one The bearing surface at end, the area of the area of the bearing surface less than the first mating groove.

6. transmission connecting structure according to claim 1, it is characterised in that: the end face of the driving link has been recessed arc Shape recess portion, the opposite one end fits of the driven member stretch in arc-shaped depression portion, and the mating groove and guide frame are arranged in institute It states in arc-shaped depression portion.

7. transmission connecting structure according to claim 6, it is characterised in that: the arc-shaped depression portion has arcwall face, with institute Stating any point on arcwall face edge is the tangent line that starting point makes the arcwall face in perpendicular, the tangent line and horizontal plane it Between form included angle A, 10 °≤A≤80 °.

8. transmission connecting structure according to claim 1, it is characterised in that: the end face protrusion of the driven member is arc-shaped, Make the tangent line of the end face in perpendicular using the end face edge of the driven member as starting point, the tangent line and horizontal plane it Between form included angle B, 30 °≤B≤60 °.

9. a kind of food processor, including the host with motor, the processing assembly that is arranged on host, it is characterised in that: institute It states and is provided with the described in any item transmission connecting structures of claim 1-8, the electricity between the motor shaft of motor and processing assembly The rotary power of machine is transferred to processing assembly by the transmission connecting structure.

10. food processor according to claim 9, it is characterised in that: the food processor is cooking machine or Minced Steak Machine, the processing assembly include cup body and stirring blade arranged in cup body, and the stirring blade has rotary shaft, the motor The transmission connecting structure is provided between axis and rotary shaft；Alternatively, the food processor is juice extractor, the processing assembly Including cup body and screw rod arranged in cup body, the transmission connecting structure is provided between the motor shaft and screw rod；Or Person, the food processor are flour stranding machine, and the processing assembly includes the flour-stirring rod for stirring face cylinder and being arranged in a face of stirring tin, institute It states and is provided with the transmission connecting structure between flour-stirring rod and motor shaft.