Adjustable Dumbbell

The present disclosure relates to the technical field of fitness equipment, particularly to an adjustable dumbbell.

A dumbbell is a common strength training equipment, typically consisting of a short bar and weight blocks at both ends, mainly used for muscle strength training, shaping, and functional exercises. Its characteristics include compact size, flexible use, and suitability for single or double-handed gripping.

To allow users to flexibly adjust the weight of the dumbbell, many adjustable dumbbells have appeared on the market, such as a rotary dumbbell disclosed in application number CN2020214260128, which includes a handle portion, weight portions located at both ends of the handle portion, and a transmission self-locking mechanism and a driven mechanism arranged at both ends of the handle portion and respectively abutting against the two weight portions; the transmission self-locking mechanism includes a transmission assembly; the transmission assembly comprises a star-shaped gear transmission mechanism, a first output screw, a long nut fitted with the first output screw, and a first screw spline splined to the first output screw; the long nut is rotationally connected to the star-shaped gear transmission mechanism, enabling the long nut to rotate under the drive of the star-shaped gear transmission mechanism, causing the first output screw to move axially through the first screw spline.

The above technical solution, through the design of a star-shaped gear adjustment mechanism, achieves the function of rotary automatic addition and subtraction of dumbbell plates. Compared with traditional dumbbells, while it significantly improves the convenience of dumbbell use, the planetary gear adjustment mechanism is relatively complex, not only resulting in higher production costs but also making it difficult to repair or replace in case of wear, leaving room for improvement.

The present disclosure provides an adjustable dumbbell to solve the problems raised in the background art.

To achieve the above object, the present disclosure adopts the following technical solutions:

An adjustable dumbbell comprises a dumbbell bar internally provided with an axially extending guide rail; connection seats arranged at both ends of the dumbbell bar, each provided with a mounting hole at a center thereof; a weight assembly comprising a plurality of stacked weight units, wherein each weight unit is provided with a through hole, and a detachable lateral interlocking structure is arranged between adjacent weight units to restrict a horizontal relative displacement between the adjacent weight units; a spindle laterally slidably arranged inside the dumbbell bar and extending into the mounting holes of the connection seats, wherein an outer surface of the spindle is provided with a helical groove and an axially extending guide groove; and a spline arranged inside the connection seat, wherein the spline is provided with a boss extending into the helical groove, and the boss presents a helical shape matching the helical groove. The guide rail inside the dumbbell bar is slidably fitted with the guide groove of the spindle to directly transmit a rotational motion of the dumbbell bar to the spindle, thereby achieving synchronous rotation of the dumbbell bar and the spindle. When the spindle is rotated, the boss slides along the helical groove, converting a rotational motion of the spindle into an axial movement. When the spindle is extended axially, a tail end thereof penetrates the connection seats and the through hole of at least one weight unit, forming a longitudinal constraint on the weight unit, allowing the weight assembly to be fixedly connected to the connection seats. When the spindle is retracted axially, the tail end thereof withdraws from the through hole, releasing the longitudinal constraint, allowing the weight assembly to be separated from the connection seats.

Another technical solution provided by the present disclosure: an adjustable dumbbell comprises a dumbbell bar; connection seats arranged at both ends of the dumbbell bar, each provided with a mounting hole at a center thereof; a weight assembly comprising a plurality of stacked weight units, wherein each weight unit is provided with a through hole, and a detachable lateral interlocking structure is arranged between adjacent weight units to restrict a horizontal relative displacement between the adjacent weight units; a spindle laterally slidably arranged inside the dumbbell bar and extending into the mounting holes of the connection seats, wherein an outer surface of the spindle is provided with a helical groove; a spline arranged inside the connection seat, wherein the spline is provided with a boss extending into the helical groove, and the boss presents a helical shape matching the helical groove; and a rotational transmission assembly that is arranged between the dumbbell bar and the spindle and is configured to transmit a rotational motion of the dumbbell bar to the spindle, achieving synchronous rotation of the dumbbell bar and the spindle while allowing the spindle to slide axially relative to the dumbbell bar. When the spindle is rotated, the boss slides along the helical groove, converting the rotational motion of the spindle into axial movement. When the spindle is extended axially, a tail end thereof penetrates the connection seats and the through hole of at least one weight unit, forming a longitudinal constraint on the weight unit, allowing the weight assembly to be fixedly connected to the connection seats. When the spindle is retracted axially, the tail end thereof withdraws from the through hole, releasing the longitudinal constraint, allowing the weight assembly to be separated from the connection seats.

Another technical solution provided by the present disclosure: an adjustable dumbbell comprises a dumbbell bar; connection seats arranged at both ends of the dumbbell bar, each provided with a mounting hole at a center thereof; a weight assembly comprising a plurality of stacked weight units, wherein each weight unit is provided with a through hole, and a detachable lateral interlocking structure is arranged between adjacent weight units to restrict a horizontal relative displacement between the adjacent weight units; a spindle laterally slidably arranged inside the dumbbell bar and extending into the mounting holes of the connection seats; a rotational transmission assembly that is arranged between the dumbbell bar and the spindle and is configured to transmit a rotational motion of the dumbbell bar to the spindle, achieving synchronous rotation of the dumbbell bar and the spindle while allowing the spindle to slide axially relative to the dumbbell bar; and an axial conversion assembly that is arranged between the spindle and the connection seat and converts a rotational motion of the spindle into an axial movement of the spindle when the spindle is rotated. When the spindle is extended axially, a tail end thereof penetrates the connection seats and the through hole of at least one weight unit, forming a longitudinal constraint on the weight unit, allowing the weight assembly to be fixedly connected to the connection seats. When the spindle is retracted axially, the tail end thereof withdraws from the through hole, releasing the longitudinal constraint, allowing the weight assembly to be separated from the connection seats.

The beneficial effects of the present disclosure over the prior art are: by providing the helical groove and guide groove on the spindle, the guide rail in the dumbbell bar that match the guide groove, and the boss on the spline that extends into the helical grooves, the spindle is rotated synchronously with the dumbbell bar when turned, allowing the boss to slide within the helical groove and extend into or retract from one or more through holes to add or remove weight plates. The structure is relatively simple, with fewer components and easier processing, helping to reduce production and maintenance costs.

Reference signs: Base (); Mounting seat (); Connecting rod (); Weight holder (); Engagement groove (); Accommodating groove (); Lug (); Weight assembly (); Weight plate (); Inner plate (); Intermediate plate (); Outer plate (); First embedding groove (); First embedded block (); Through hole (); Dumbbell bar (); First spindle (); Helical groove (); Guide groove (); Guide rail (); Outer sleeve (); Positioning notch (); Inner sleeve (); Positioning block (); Calibration dial (); Connection seat (); Mounting hole (); Spline (); Boss (); Positioning groove (); Side plate (); First penetrating hole (); Clamping plate (); Washer (); Flange (); Cover (); Second penetrating hole (); Opening (); Limiting block (); Accommodating cavity (); Disc body (); Arc segment (); Slider (); Passage slot (); Elongated hole (); Recess (); Viewing window (); Second embedding groove (); Second embedded block (); Third embedded block (); Top notch (a); Side notch (b); Inner wall (c).

The technical solution in the embodiment of the present disclosure will be clearly and completely described below with reference to the drawings. Obviously, the described embodiment is part of, rather than all of the embodiments of the present disclosure. The following description of at least one exemplary embodiment is illustrative in nature and is in no way intended to limit the present disclosure, its application or uses. Based on the embodiments in the present disclosure, all other embodiments obtained by those skilled in the art without creative work belong to the scope of protection of the present disclosure.

It should be noted that the terminology used here is only for describing specific embodiments, and is not intended to limit exemplary embodiments according to the present application. As used herein, the singular form is also intended to include the plural form unless the context clearly indicates otherwise. Furthermore, it should be appreciated that when the terms “comprising” and/or “including” are used in this specification, they specify the presence of features, steps, operations, devices, components and/or combinations thereof.

Unless otherwise specified, the relative arrangement of components and steps, numerical expressions and numerical values set forth in these embodiments do not limit the scope of the present disclosure. At the same time, it should be appreciated that for the convenience of description, the dimensions of various parts shown in the drawings are not drawn according to the actual scale relationship. Techniques, methods and equipment known to those skilled in the art may not be discussed in detail, but in appropriate cases, they should be regarded as part of the authorization specification. In all the examples shown and discussed herein, any specific values should be interpreted as illustrative, and not as limiting. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar numbers and letters indicate similar items in the following drawings, therefore once an item is defined in one drawing, it does not need to be further discussed in subsequent drawings.

An adjustable dumbbell includes a base, two weight assemblies, and a dumbbell bar(refer to).

In this embodiment, referring to, the baseincludes two opposing mounting seats. Two symmetrically arranged connecting rodsare inserted between the two mounting seats, and a weight holderis disposed between the two connecting rods. The two weight assembliesare symmetrically placed between the weight holderand the mounting seats.

In other embodiments, referring to, the weight holderis provided with engagement grooveson the side facing the two connecting rods, and both connecting rodsare engaged in the engagement grooves.

In other embodiments (not shown), the weight holdermay be fixedly installed between the two connecting rods.

In other embodiments (not shown), anti-slip pads are fixedly installed at the bottoms of the weight holderand the two mounting seats. The anti-slip pads (typically made of rubber, silicone, or other high-friction materials) significantly increase the friction between the base and the contact surface (such as a table or floor). When the weight assemblyis placed on the base, the anti-slip pads effectively prevent accidental sliding, displacement, or tipping of the base.

In other embodiments (not shown), there may be two weight holders, with a rotating structure placed between the two weight holders, allowing the two weight holdersto rotate relative to each other. This facilitates the storage of the base. Additionally, when the two weight holdersare rotated to an appropriate angle, the two mounting seatsform an inverted V-shape, making it convenient to place kettlebells. Thus, the basecan accommodate both dumbbells and kettlebells.

In this embodiment, referring to, the weight assemblyconsists of a plurality of weight plates. Adjacent weight platesare longitudinally slidably fitted, and a through holeis provided at the center of each weight plate.

In other embodiments, referring to, the plurality of weight platesinclude an inner plate, several intermediate plates, and an outer plate. Both side of the inner plate, both side of the intermediate plates, and the side of the outer platefacing the intermediate platesare all equipped with first embedding groovesand first embedded blocks. Two adjacent weight platesare interconnected through a complementary structure of the first embedding groovesand the first embedded blocks.

Here, referring to, the diameters of the first embedding grooveand the first embedded blockat the top of the weight plateis much larger than that those of the first embedding grooveand the first embedded blockat the bottom. The larger top structure of the weight plateacts like a funnel or guide. When a user inserts a new weight plateonto an existing one, even if the initial alignment is slightly off, the larger top first embedding groovecan more easily “capture” and accommodate the larger top first embedded blockof another weight plate. This significantly increases the fault tolerance during initial contact, allowing the insertion process to begin without requiring extremely precise alignment. This greatly simplifies the assembly (stacking) operation, especially when a plurality of weight platesneed to be added quickly, thus enhancing the user experience.

In other embodiments, referring to, when a weight plateis placed vertically, the inner wall diameter of the first embedding grooveis made larger than the diameter of a side notch, while the shape of the first embedded blockmatches the first embedding groove. When the first embedded blockon one weight plateis inserted into the first embedding grooveof another weight platealong a top notch, the main body of the first embedded blockis confined within the spacious interior of the first embedding groovesince the inner wall diameter is larger than the side notch diameter. Since the diameter of the first embedded block's main body exceeds that of the side notch, the first embedded blockis unlikely to disengage from the side notch, preventing the first embedded blockfrom being disengaged from the first embedding groovealong the direction of the side notch. When a plurality of weight platesare stacked horizontally, workers can take up them without worrying about separation of the weight plates due to minor collisions or tilting, reducing the risk of injury or equipment damage. The mechanical interlock between a plurality of weight platesis achieved solely through geometric shapes, eliminating the need for additional parts like bolts or clips, thereby simplifying structure and assembly.

In other embodiments, the weight assemblyis not limited to weight platesbut may also include one or more weight blocks or weight balls.

In other embodiments, referring to, the side surface of the mounting seatfacing the weight holderis fixed with a third embedded block. By slidable fitting of the third embedded blockwith the first embedding grooveon the outer plate, the weight assemblyis more securely placed between the weight holderand the mounting seatwithout lateral sliding.

In this embodiment, referring to, both ends of the dumbbell barare equipped with connection seatsfor longitudinal slidable fitting the weight assembly. The connection seatshave mounting holescoaxial with the through holes. The two ends of the dumbbell barand the two connection seatsare in one-to-one correspondence and are rotatably fitted with each other. Inside the dumbbell bar, two spindlesare arranged laterally and are slidably horizontally fitted with the dumbbell bar, and the spindleextends into the mounting holeon the same side.

In other embodiments (not shown), the dumbbell baris rotationally connected to the connection seatthrough bearings.

In other embodiments, referring to, the outer surface of the spindleis provided with a helical groove, and both the top and bottom are equipped with axially extending guide grooves. The dumbbell barcontains guide railsthat are slidably fitted with the two guide grooves. Referring to, the connection seathouses a splinesleeved outside the spindle. The center of the splineis provided with a central hole, into which the spindleextends. The inner wall of the central hole is fixedly provided with a bossthat extends into the helical groove, where the bossadopts a helical shape matching the helical groove.

When the dumbbell barrotates, the bossslides within the helical groove, making the spindleextend into one or more through holesor be disengaged from the through holes.

Here, the slidable fitting between the guide railsand the guide groovesprevents the spindlefrom deviating during translation, enhancing stability. Simultaneously, the mutual constraint between the guide railsand the guide groovesensures that when the dumbbell barrotates, it drives the spindleto rotate synchronously through the guide railsand guide grooves.

In this embodiment, referring to, the dumbbell barincludes an outer sleeveand two inner sleeveswithin the outer sleeve. The two inner sleevesare arranged left and right, each corresponding to one of the two spindlesand sleeved over the outer surfaces of the corresponding spindles. Both guide railsare fixed to either the top wall or bottom wall of the inner sleeves.

In other embodiments, referring to, both ends of the outer sleeveare equipped with positioning notches, while the inner sleevesare fixedly provided with positioning blocksfitted with the corresponding positioning notches. By providing the positioning notchesand positioning blocks, after the inner sleevesare inserted into the outer sleeveand the positioning blocksare engaged and fitted with the positioning notches, the user can rotate the outer sleeveto synchronously rotate the inner sleeves, making assembly more convenient.

In this embodiment, referring to, the connection seatincludes a side platewith a first penetrating holeand a coverwith a second penetrating hole. One side of the side plateis slidably connected to the weight assembly, while the coveris placed on the other side of the side plateand is fitted with the side plateto form an accommodating cavity. The mounting holeis formed by the fitting of the first penetrating holeand the second penetrating hole. Referring to, the end of the dumbbell barpasses through the second penetrating holeand extends into the accommodating cavity, with the splinepositioned at the first penetrating hole.

When the spindlemoves, the entire motion occurs within the accommodating cavity, preventing accidental collisions with external objects and ensuring continuous, stable operation.

In other embodiments, referring to, the side plateis fixed with two clamping platessymmetrically arranged around the first penetrating holeon the side facing the spline. A clamping groove matching the splineis formed between the two clamping platesand the first penetrating hole, allowing the splineto be engaged and fitted with the clamping groove.

Here, the cross-section of the clamping groove is non-circular, matching the outer profile of the spline. The splinecan be assembled by snapping the splineinto the clamping groove without relative rotation of the spline.

In other embodiments, referring to, one side of the splinefeatures a positioning groove. A washeris installed inside the first penetrating hole, with one side of the washerextending into the clamping groove and extending radially outward to form a flange. The flangeabuts against the groove bottom of the positioning groove, while the inner diameter of the washermatches that of the spline.

Here, the flangeis clamped between the side plateand the spline, serving as a stopper to ensure the splineremains firmly fixed in its designed axial position without displacement due to vibration, load, or operation.

In this embodiment, referring to, the outer side of the dumbbell baris fixed with a disc bodythat is rotatably fitted with the accommodating cavity. One side of the disc bodyis fixed with a plurality of arc segmentsdistributed circumferentially, with gaps between adjacent arc segments.

In other embodiments, referring to, the lower side of the coverhas an opening. Referring to, a slidercapable of sliding vertically is arranged inside the accommodating cavity. Referring to, the side of the sliderfacing the disc bodyis provided with a passage slot, which runs through the front and rear sides of the slider.

In other embodiments, referring to, the weight holderis provided with accommodating grooveson both sides facing the two mounting seats. The diameter of the accommodating groovesis the same as that of the connection seat, allowing the connection seatto be placed inside the accommodating grooves. The bottom wall of each accommodating grooveis equipped with two lugs, which correspond one-to-one with the two openings.

When the connection seatis placed on the weight holder, the lugspass through the corresponding openingsand push the slider, aligning the passage slotwith the arc segmenton the same curve. At this point, there is no interference between the disc bodyand the slider, meaning the disc bodyis unlocked, allowing the dumbbell barto be rotated to adjust the position of the spindle. When the connection seatis separated from the weight holder, the sliderslides downward, causing the passage slotto misalign with the arc segment. The side of the sliderthen lies along the extension direction of the arc segment, creating interference between the disc bodyand the slider. The disc bodyis locked by the slider, and the dumbbell barcannot be rotated to adjust the spindle's position. Through this structural design, when the dumbbell is placed on the base, the dumbbell barcan be rotated to adjust the spindle's position for adding or removing weight plates. When the dumbbell is removed from the base, the disc bodyis locked by the slider, preventing the dumbbell barfrom rotating autonomously and avoiding accidental detachment of the weight platesduring training, ensuring safe and worry-free use.

In other embodiments, referring to, the slideris equipped with an elongated hole, while the coverfeatures a sliding groove and a limiting blockwithin the sliding groove. The slideris slidably fitted with the sliding groove, and the limiting blockextends into the elongated hole, thereby restricting the sliderto linear movement along the sliding groove's direction.

In this embodiment, please refer to. The side plateis provided with two hollow cylinders symmetrically arranged around the first penetrating holeon the side facing the cover. Each cylinder contains a spring-loaded ball and an elastic component connected to it. The disc bodyhas a plurality of positioning holes on its corresponding circumferential surface, with diameters smaller than that of the spring-loaded ball. When the disc bodyis rotated, the positioning holes misalign with the cylinders, causing the disc bodyto press the spring-loaded balls, retracting them into the cylinders. During this process, the elastic component is compressed to store energy. Once the disc bodyrotates to the next position, the spring-loaded balls quickly snap into the new positioning holes under the spring force, producing a distinct “click” sound. This sound provides clear feedback to the user for weight position switching.

In other embodiments, the elastic component may be a spring or an elastic pad.

In this implementation, please refer to. The connection seatis provided with a recesson the side facing the dumbbell bar, and the inner bottom wall of the recesshas a viewing windowconnected to the accommodating cavity. Please refer to. A calibration dialis fixed on the outer side of the dumbbell barwithin the accommodating cavity, with the outer sidewall of the calibration dialpositioned directly below the viewing window. The outer circumference of the calibration dialis marked with a plurality of weight gradations, each displaying a different numerical value.

When the user adds or removes weight plates, the rotation of the dumbbell bardrives the calibration dialto rotate, causing the weight gradations displayed in the viewing windowto change. This allows the user to observe the variation in weight gradations through the viewing window, providing an intuitive confirmation of the current weight setting.

In this embodiment, please refer to. A second embedding grooveand a second embedded blockare arranged on the surface of the connection seaton a side away from opposite the dumbbell bar. The first embedding grooveon the side of the inner plateaway from the intermediate plateis used for fitting with the second embedded block, while the first embedded blockon the same side of the inner plateis used for fitting with the second embedding groove.

It should be noted that a plurality of weight platesare prevented from lateral movement between adjacent weight platesthrough the fitting of embedding grooves and embedded blocks. Simultaneously, the spindlepasses through the through holeto prevent longitudinal movement of the corresponding weight plate, thereby locking the weight plate. Additionally, by providing a second embedding grooveand a second embedded blockon the connection seat, a lock is formed between the connection seatand the weight platewhen the spindlepasses through the through hole. When the spindleis disengaged from the through hole, the user can lift the dumbbell barto separate the connection seatfrom the weight plate.