Abstract: An attachment for pushable devices, such as strollers, carts, wagons, wheelchairs, and the like, fits between a jogger or walker and a pushable device and allows for more natural running or walking motion while pushing the device. In some embodiments, the attachment includes dampening functions to smooth the connection between the pusher and device, which, in conjunction with an overall geometry that limits interference with the pusher's walking or running motion, provides a smoother ride for an occupant and/or contents of the device. In other embodiments, the attachment provides a substantially rigid connection between the device and the user. The attachments allow the pusher's movement to help steer the device, and, while allowing for mostly hands-free use, reduce unwanted movements translated into the device from the pusher's motions. The attachments described herein allow pushers to comfortably run/jog/walk hands-free while pushing the device in front of them.

Abstract: A handle extension for a stroller is described. Embodiments of the handle extension can be implemented to allow for the natural movement of arms of a user while pushing a stroller. Embodiments include a pair of handle extensions rotatably coupled to a stroller handlebar. The handle extensions can rotate about the stroller handlebar and include a means to allow for movement of a handle of the handle extension in addition to the handle extension rotating about the handlebar.

Abstract: A luggage towing apparatus, wherein the luggage has a wheel to move on a surface and an opposing handle. The luggage apparatus includes a bracket constructed of a beam having first, mid, and second end portions, the first end portion having an aperture, the second end portion having a flexible hook being removably engagable to the luggage handle. The mid portion has a finger channel constructed of a partial sidewall, wherein the partial sidewall terminates in an open gap that operationally allows a user's finger to pass therethrough wherein the sidewall acts as a finger rest to facilitate finger movement thus moving the bracket to engage and disengage the flexible hook from the luggage handle. The luggage towing apparatus further includes a strap that is affixed the aperture, wherein operationally the strap is looped around a torso of the user to enable pulling the luggage across the surface hands free.

Abstract: A pair of grips (2) for tippable apparatus (4) comprising at least one wheel (6), a body portion (8) for receiving a load (10), and a pair of handles (12) by which the tippable apparatus (4) is able to be pushed and tipped about the wheel (6), and the pair of grips (2) being such that each grip (2) comprises: (i) a connecting portion (14) for connecting to one of the handles; (ii) a hand grip portion (16); (iii) at least one guide slot (18) in the hand grip portion (16); and (iv) at least one slide portion (20) which extends from the connecting portion (14) and into the guide slot (18), and the grip (2) being such that: (v) the guide slot (18) is curved, and (vi) the slide portion (20) is retained in the guide slot (18) and is slideable backwards and forwards in the guide slot (18) in order to allow the tipping of the tippable apparatus (4) about the wheel (6) and without a person having to change their hand position on the grip (2).

Abstract: A vehicle for a standing rider has a single surface-engaging wheel; a pair of foot supports, one on each side of the wheel, for supporting a standing rider astride the wheel in a position facing forward; a frame that mounts the wheel and forms a forward riser extending up and forward from the wheel to a position to be grasped by a rider standing on the foot supports to enable the rider to achieve balance and stability while standing and riding. A rearward riser extends up and rearward of the wheel to a position to be grasped by a pusher to enable the pusher to advance, balance and guide the vehicle.

Abstract: This disclosure concerns a method of configuring a foam spring mattress including assigning a relevance rating to a foam spring location in the mattress, wherein the relevance rating relates to the relevance of the location to the impact it has on the firmness feel of the mattress and configuring a plurality of foam springs of varied firmnesses in a mattress according to a placement pattern to obtain a firmness, wherein the placement pattern is generated based on a match between a foam spring of a particular firmness and the relevance rating.

Abstract: A harness for pulling a carriage includes a waistband and a plurality of pressure-distributing plates. A pulling assembly for coupling the harness to the carriage includes a drawbar coupled to the carriage and a spring coupled to the drawbar and to the harness. A length and an angle of the spring are adjustable.

Abstract: Provided is a hybrid baby carrier capable of reducing a load of weight of a baby that is transferred to a guardian who wears a baby carrier. In accordance with an embodiment of the present invention, the hybrid baby carrier may include a main body configured to form a space where a baby is seated, a strap connected to the main body and configured to be worn by a guardian so that the guardian supports the load of the baby, and a support unit downwardly extended from the main body and configured to distribute the load of the baby toward a ground.

Abstract: A collapsible, wheeled travois that may be used to transport multiple passengers in a hands-free mode is provided. The wheeled travois is quickly and easily assembled and includes detachable wheels, support members, load carrying surface, and harness.

Abstract: A collapsible, wheeled travois that may be used to transport multiple passengers in a hands-free mode is provided. The wheeled travois is quickly and easily assembled and includes detachable wheels, support members, load carrying surface, and harness.

Abstract: A portable, foldable, and multifunctional mobility aid apparatus that assists a user in standing, sitting, and/or walking process. The apparatus has an integrated power source and is based on 4 wheels. Users can stand on it and drive it as an electric mobility device, or disable it and use it as a passive walker. The apparatus has a pair of supporting beams with adjustable width to be placed under the user armpits and support the user in standing up, sitting down, and/or moving around. The apparatus can be controlled by a control panel mounted on a pair of handles, and its functions can be controlled by the user with no need for help from another person. The apparatus can be minimized by a combination of multiple telescopic vertical minimization mechanisms and multiple folding mechanisms.

Abstract: A carriage assembly, harness and towing assembly is disclosed, which allows for significant freedom of movement for a user. The carriage preferably comprises at least a single, two-wheel axis and at least one motion damping device provided with a plurality of coupling members attaching the carriage to the harness. One object of the disclosure is to provide an apparatus that allows a user to comfortably tow a child or other tow load while participating in a variety of exercise or general travel-related activities.

Abstract: A convertible trailer assembly is provided that can be pushed or pulled. The trailer assembly can be converted between pushed or pulled operation or provided as a retrofit assembly for a stroller that allows its conversion between pushed or pulled operation. The Assembly includes a linkage assembly to provide a smoother towing experience for the user. The linkage uniquely takes up the constant jarring motion that is incompatible as between the user and the trailer and dissipates it in a toggle that consists of a lever extending upwardly from a tow point on the trailer. When accelerating or going uphill the toggle pulls forward, at equilibrium the toggle motion absorbs the incremental differences in acceleration/deceleration and at the rear limit of its range of motion, the toggle pushes a brake actuator to slow the trailer.

Abstract: System and method for carrying loads by a user are disclosed. According to embodiments of this invention a load is carried attached to the back of the user and concurrently vertically supported to the ground on supporting means. The system comprising means that allow vertical free movements of the load with respect to the user's back within a defined range so that the load substantially carried by the supporting means while providing stable attachment of the load to the user's back in two other linear axes of freedom and in all three circular axes of freedom. The supporting means includes means to adjust the support according to the user's height and to the grounds bumpiness.

Abstract: A convertible trailer assembly is provided that can be pushed or pulled. The trailer assembly can be converted between pushed or pulled operation or provided as a retrofit assembly for a stroller that allows its conversion between pushed or pulled operation. The Assembly includes a linkage assembly to provide a smoother towing experience for the user. The linkage uniquely takes up the constant jarring motion that is incompatible as between the user and the trailer and dissipates it in a toggle that consists of a lever extending upwardly from a tow point on the trailer. When accelerating or going uphill the toggle pulls forward, at equilibrium the toggle motion absorbs the incremental differences in acceleration/deceleration and at the rear limit of its range of motion, the toggle pushes a brake actuator to slow the trailer.

Abstract: Apparatus and methods for propelling a multiple-wheeled golf bag cart over a terrain are described. In one embodiment, the apparatus is configured to be attached to a handle of the golf bag cart and further configured to be attached to the waist of a golfer. The apparatus includes a belt member for attachment to the waist of the golfer, a deformable member configured to be disposed between the cart handle and the belt member for controlling movement of the cart while the cart is being towed, and a mounting member for attachment to the handle for connecting the deformable member to the handle.

Abstract: A training device for an ambulatory user is disclosed. The training device includes a harness to attach to the ambulatory user, a pair of wheels extending from opposite sides of a crossbar, and a weight holder connected between the crossbar and the harness. The weight holder is adapted to hold one or more removable weights. The training device can further include an elongated shock absorber connected to the harness to absorb compressive and expansive forces exerted on the harness at least in part by the ambulatory user.

Abstract: A carriage and incorporated harness and towing assembly which allows for significant freedom of movement for a user and a safe and comfortable ride for a passenger is disclosed. The towing assembly comprises a flexible, semi-resilient member surrounded by a plurality of rigid linkages, a fixed towing member and a harness coupling member. The carriage is comprised of at least a single, two-wheel axis and at least one motion damping device. One object of the disclosure is to provide an apparatus that allows a user to comfortably tow a child, toddler or infant while participating in a variety of exercise or general travel-related activities.

Abstract: A system for efficient manual towing of a wheeled golf trolley using a flexible tether and harness mountable to the torso of a user.

Abstract: A carriage and incorporated harness and towing assembly which allows for significant freedom of movement for a user and a safe and comfortable ride for a passenger is disclosed. The towing assembly comprises a flexible, semi-resilient member surrounded by a plurality of rigid linkages, a fixed towing member and a harness coupling member. The carriage is comprised of at least a single, two-wheel axis and at least one motion damping device. One object of the disclosure is to provide an apparatus that allows a user to comfortably tow a child, toddler or infant while participating in a variety of exercise or general travel-related activities.

Abstract: A rolling resistance producing apparatus is tethered to trail behind a person includes a longitudinally aligned fabric panel stretched on a frame which also engages the rear end of an elastomeric band that is stretched through a sheath formed in the panel to engage a harness tied to selected limbs of the person to provide resistance thereto. The trailing end of the frame is supported on a wheel to follow the person as she or he are moving. A measurement system sensing the movement of the wheel then records the rate of the movement to provide an indication of fatigue.

Abstract: A carriage and incorporated harness and towing assembly which allows for significant freedom of movement for a user and a safe and comfortable ride for a passenger is disclosed. The towing assembly comprises a flexible, semi-resilient member surrounded by a plurality of rigid linkages, a fixed towing member and a harness coupling member. The carriage is comprised of at least a single, two-wheel axis and at least one motion damping device. One object of the disclosure is to provide an apparatus that allows a user to comfortably tow a child, toddler or infant while participating in a variety of exercise or general travel-related activities.

Abstract: The Dive Caddy is a two wheeled land vehicle with it's primary purpose being to transport scuba diving equipment across tough terrain such as sandy beaches, rocky trails, and other hard to traverse, or reach scuba diving, or free diving locations. It is different than other prior carts in as that it has a breaking system for traveling down hills, And can be fitted with an auxiliary battery powered booster motor to traverse uphill, or help bring itself out of hard to exit situations, and also has a bench seat to stage a completed scuba unit for the diver to sit on while dawning his equipment. Another new feature of the Dive Caddy is that it has the ability to change tires for different types of terrain, be it sandy beaches, rocky hills, or mud, the Dive Caddy can adapt to them all.

Abstract: A tent and backpack combination apparatus includes a satchel has a front wall, a back wall, a first end wall and a second end wall. A pair of shoulder straps is attached to the back wall. The satchel has an elongated opening therein for accessing an interior thereof. A support is attached to and extends through the satchel. The support includes a lower portion extending away from the first end wall of the satchel that is configured to engage a ground surface. The support includes an upper portion extending away from the second end wall that is configured to support the satchel in a spaced relationship with the ground surface and to angle the satchel upwardly from the first end wall to the second end wall. A sleeve has an open end and the support is positionable in the open end and covered by the sleeve to define a tent.

Abstract: Apparatus and methods for propelling a multiple-wheeled golf bag cart over a terrain are described. In one embodiment, the apparatus is configured to be attached to a handle of the golf bag cart and further configured to be attached to the waist of a golfer. The apparatus includes a belt member for attachment to the waist of the golfer, a deformable member configured to be disposed between the cart handle and the belt member for controlling movement of the cart while the cart is being towed, and a mounting member for attachment to the handle for connecting the deformable member to the handle.

Abstract: A carriage and incorporated harness and towing assembly which allows for significant freedom of movement for a user and a safe and comfortable ride for a passenger is disclosed. The towing assembly comprises a flexible, semi-resilient member surrounded by a plurality of rigid linkages, a fixed towing member and a harness coupling member. The carriage is comprised of at least a single, two-wheel axis and at least one motion damping device. One object of the disclosure is to provide an apparatus that allows a user to comfortably tow a child, toddler or infant while participating in a variety of exercise or general travel-related activities.

Abstract: A highly maneuverable, multi-use, human-powered cart for comfortably transporting substantial loads. A cargo basket is defined between upper and lower subframes forming a rigid, low-profile frame at the middle of the trailer. The frame rear terminates in a pair of articulated forks supporting a large wheel that bears most of the cargo weight. An adjustable and pivoted yoke assembly at the front of the frame supports an articulated harness assembly worn by the user. The yoke assembly preferably comprises an upwardly angled yoke tube slidably coupled and pivoted to the frame front at the tube's lower end. Height adjustments are facilitated by the slidably adjustable yoke tube relative to the frame to accommodate various user heights. The device folds for storage or for carrying on the users back while crossing challenging terrain.

Abstract: A versatile carrier is provided having the ability to switch from a configuration being towed behind a user to a configuration being carried on the user's back like a conventional backpack. The carrier is comprised of a frame having a front end and a rear end, a linkage member having a front end and a rear end, a harness, and at least one wheel coupled to the rear end of the frame. The front end of the linkage member is coupled to the harness while the rear end is couple to the frame. The coupling allows the front end of the frame to be supported by the linkage member. The coupling also allows the frame to transfer from the towed position to the user's back with ease and without removal of the carrier from the user.

Abstract: A versatile carrier is provided having the ability to switch from a configuration being towed behind a user to a configuration being carried on the user's back like a conventional backpack. The carrier is comprised of a frame having a front end and a rear end, a linkage member having a front end and a rear end, a harness, and at least one wheel coupled to the rear end of the frame. The front end of the linkage member is coupled to the harness while the rear end is couple to the frame. The coupling allows the front end of the frame to be supported by the linkage member. The coupling also allows the frame to transfer from the towed position to the user's back with ease and without removal of the carrier from the user.

Abstract: A hands-free towing apparatus fro strollers, pet carriers and other carriages is described. The apparatus comprises a belt-attachment device, a frame, and a carriage-attachment device. The belt-attachment device can be a padded belt attached to a formed back-plate that a caregiver wears on his or her torso. A frame having a first end and a second end joins the belt-attachment device and the carriage-attachment device. A lockable joint can be incorporated within the frame to allow the apparatus to fold. The first end of the frame attaches to the belt-attachment device via a joint mechanism. The frame extends back from the caregiver to a carriage where the second end of the frame attaches to the carriage via the carriage attachment device.

Abstract: An apparatus designed to allow a runner to run/jog with a baby jogger by allowing natural running arm movement through the use of a twin shock absorbing connector arm assembly being attached at one end to a baby jogger and the other to the waist of the jogger by means of a waist belt with pivots at either end of the arm assembly to allow for variation in size/height of jogger and operator.

Abstract: Devices and methods of transporting a load (e.g., a backpack) over surfaces, such as an uneven terrain, are disclosed. In one instance, a frame and harness designed to attach to a standard backpack are disclosed. The device allows a hiker to pull or carry their backpack. In one embodiment, the cart has a frame with one or more wheels mounted at one end, and one or more handles extending beyond the opposite end. While being used to pull the backpack, the cart can be partially suspended by straps connecting the shoulder harness and the handles, thus freeing the hiker's hands without unduly restricting his/her freedom of movement. The cart can also be designed so that an attached backpack may still be carried in the normal fashion without detaching it from the cart. Other features of such devices, and methods relating to the use of load-bearing devices are also disclosed.

Abstract: A roller-tow harness for wear by a jogger or skater to tow behind him a second person on roller skates or roller blades. The harness consists of a wide belt that has fastening means in the back of the belt for connecting to at least one tow rope equipped with a grip handle for easy gripping by a second person that is being towed behind. The harness may optionally consist of a pair of shoulder straps to further stabilize the belt on the wearer and to further distribute the load from the wearer's waist to his chest and back.

Abstract: A device for towing a trolley includes a rigid shaft having a proximal end and a distal end. A user-releasable clamp is associated with the distal end and is dimensioned to grip a handle of the trolley. A user-releasable coupler is associated with the proximal end for coupling the device to a user. Both the clamp and the coupler being user-releasable provides great flexibility for use with a wide variety of trolleys and for ease of storage.

Abstract: A hands-free jogging stroller adaptor apparatus with shock absorbing properties is provided. The adaptor allows a jogger to utilize a jogging stroller without interruption of natural arm and leg cross-motion as would occur when pushing the stroller with hands or forearms. Telescopic tubes are situated between a jogger and the stroller, the tubes being equipped with an intermediary shock absorber whereby the motion of the jogger will not cause uncomfortable ‘bumping’ of the stroller or a child inside. The adaptor is worn by a jogger through the use of a waist belt. The adaptor is attached to the stroller by means of an interlocking bayonet-cup fitting.

Abstract: A highly maneuverable, multi-use, human-powered cart for comfortably transporting substantial loads. A cargo basket is defined between upper and lower subframes forming a rigid, low-profile frame at the middle of the trailer. The frame rear terminates in a pair of articulated forks supporting a large wheel that bears most of the cargo weight. An adjustable and pivoted yoke assembly at the front of the frame supports an articulated harness assembly worn by the user. The yoke assembly preferably comprises an upwardly angled yoke tube slidably coupled and pivoted to the frame front at the tube's lower end. Height adjustments are facilitated by the slidably adjustable yoke tube relative to the frame to accommodate various user heights. The device folds for storage or for carrying on the users back while crossing challenging terrain.

Abstract: A towable bag comprises a body having at least one wheel, a tow bar comprising a plurality of articulated sections, one end of the tow bar being releasably attached to the body of the bag and the second end of the tow bar being adapted to releasably engage a coupling means being worn by the user.

Abstract: An wheelbarrow attachment for a typical wheelbarrow, the attachment removably fitting over the lip and bucket of the back of the wheelbarrow and therefrom extending upward and backward from the rear of the bucket. The u-channels fitting the bucket are connectively braced. Inner uprights attach to the u-channels and are adjustably fitted for height, and fore and aft adjustment of a padded cross plate connecting the inner uprights. A user braces and pushes with his/her body, offering greater force for propelling the wheelbarrow and greater stability in handling a loaded wheelbarrow.

Abstract: A harness device, an associated kit and a method of using same are described for use in allowing a user to push an attached stroller without the need for the user's arms while simultaneously dampening undesirable up and down vertical rocking motions on the stroller which may be brought about from strides of the user walking, jogging or running. The device includes the interconnected elements of a clamp; a joining bar; a ball joint; an elongated vertical slot joint; a base plate; a waist belt; a first belt coupler; and a second belt coupler. The kit includes the unassembled components of the device. The method of using same includes the steps of affixing, grabbing, grasping; jogging, locking, obtaining, placing, pushing, running, sliding, walking, and wrapping.

Abstract: An extraction machine for cleaning a floor surface has a front and a rear and is movable by an operator relative to the floor surface in a forward direction of travel to clean the floor surface. The extraction machine also has a cleaning solution dispenser capable of dispensing a cleaning solution onto the floor surface and a recovery system for extracting a dirty solution from the floor surface. A towline is connected at one end to the extraction machine and is configured for being supported by the operator at an opposite end thereof such that movement of the operator in the forward direction of travel causes tensioning of the towline. The tension in the towline applies a pulling force to the extraction machine to move the extraction machine in the forward direction of travel.

Abstract: An improved utility cart is presented which can be configured in various ways so as to allow it to be: used for hauling game or fishing supplies, used as a seat-backed chair, or conveniently backpacked over rough terrain.

Abstract: The hiker's trail carrier may be used for transport of cargo while walking or hiking. The trail carrier may have a pair of lower longitudinal members having a wheel rotatably mounted therebetween at an axle end of each and a transverse member attached between the lower longitudinal members intermediate the axle ends and a forward end of each. A pair of upper longitudinal members may be spaced apart and attached to the transverse member and a pair of vertical members may be attached to the upper longitudinal members and to the axle end. A pair of handle members may be pivotally attached to the lower longitudinal members intermediate the axle end and the forward end.

Abstract: An ambulation aid which has a support structure for the patient that both supports the patient's weight, and is movable laterally with respect to the frame to accommodate sideways hip movement of the patient's gait. The inventors have observed that a patient's hip will shift laterally as the patient steps forward and places weight on the forward stepping leg. This causes prior art ambulation aids to jerk sideways. The present invention overcomes this by providing a support structure which can move sideways without requiring the entire frame to move sideways. In one embodiment, the support structure slides in a track behind the patient, allowing lateral movement. In another embodiment, the support structure includes a belt which either slides through rollers behind the patient, or is attached but is flexible to allow hip movement, or is attached to a slider behind the patient.

Abstract: The device for transporting a load comprises a chassis including two longitudinal girders crossing each other while extending one above or underneath the other so as to form the general shape of an asymmetrical X, the height of the V of the upper portion being equal to N times the height of the V of the lower portion (e.g. N=3). A device for support on the ground is arranged at the lower end of the lower V, while the ends of the legs of the upper V comprise handles. Braces are provided to ensure a parallelism between an axis of a supporting element of the support device, on one hand, and a straight line connecting the ends of the handles, on the other hand. The load is placed at least partially on a seat formed by two cross members that are arranged on either side of the crossing point of the longitudinal girders.

Abstract: A cart which is capable of pulling loads over rough terrain. The cart comprises a frame composed of two side members attached together by a base platform in which at least one wheel is attached to the distal ends of the two side members. Each of the two side members are designed to form an downward bent distal end at the rearward section in which the at least one wheel is attached. Also each of the two side members have an upward bent portion at the middle section which raises the middle section to approximately the level of the shoulder height of the user. Finally each of the two side members have a downward bent portion at the forward section which is intended to fit over the user's shoulder so that the weight of the load mounted on the base platform may be partially balanced over the user's shoulders. Attached to each side members are a pair of hand grips and a pair of shoulder pads which afford the user a way of pulling the cart.

Abstract: A therapeutic walking aid is adapted to support a patient in an upright position The walking aid includes side portions at least partially defining an open interior space sized to accommodate the patient. The walking aid includes elongated arm supports extending along side portions of the walking aid and a back support extending upwardly to an elevation above the arm supports and extending across a back portion of the walking aid. The arm supports cooperate with the back support in order to provide support for a patient's arms and upper body. The walking aid can be adapted to be wheelchair accessible in order to facilitate a patient's transfer from the walking aid to a wheelchair in a safe and efficient manner. The walking aid includes a releasable support system as well.

Abstract: A golf cart towing device includes a bracket assembly which is selectably attached along a tongue of a golf cart and adjustable to fit cart tongues of various breadth. A connector rod is angularly adjustable relative to the handle and includes a hook end for engaging an eyelet extending from a belt worn by the golfer. A releasable latch on the hook end maintains the hook end within the eyelet. The various adjustments of the bracket and/or the connector rod allow the golf cart to be effectively towed by persons of differing statures/physiques.

Abstract: A harness to interconnect an operator with a baby stroller for hands-free propulsion and control of the stroller provides two similar spaced connecting arms each having vehicle connectors at first ends to releasably attach to a stroller and rod caps at second ends to releasably attach to belt connectors carried by a belt releasably positionable about the operator's waist. The vehicle connectors are releasably fastenable in spaced positions about either horizontal or vertical structural elements of the baby stroller. The belt connectors are fixedly attached in spaced relationship to the belt. The joinder of the connecting arms to the vehicle connectors at the first ends may be articulating for motion primarily in a vertical plane to accommodate operator motion while maintaining steerage control for the stroller and the belt connectors may accommodate operator motion by resilient deformation or loose positioning of the belt about the operator.

Abstract: A golf bag cart handle assembly is provided for pushing a golf bag cart. In use the handle wraps around at least a portion of the golfer's body and presents the golfer with horizontal and vertical gripping positions directly in front of the golfer. A preferred embodiment of the handle assembly comprises connecting means for attachment to the golf bag cart, height, length, and tilt adjustment means, an outward member bending away from the major longitudinal axis of the golf bag cart, a first horizontal member, a first vertical member bending upward, a horizontal transverse member perpendicular to the major longitudinal axis of the golf bag cart, a second downward vertical member and a second horizontal member. Also disclosed is a belt-mounted pulling assembly that clips onto the handle to allow pulling of the cart.

Abstract: A brake system for a wheeled walker frame having two walker frame legs with two telescopically adjustable frame tubes, of which one frame tube supports in its upper region a handle and a brake lever and the other is provided in its lower region with a brake device for braking a wheel. A telescopically adjustable brake rod is disposed within the frame tubes, between the brake lever and the brake device, and includes two parallel rods of which one is interconnected with the brake lever and the other is interconnected with the brake device. An axial longitudinal adjustment of the frame tubes to the desired vertical position synchronously causes a corresponding alteration of the length of the brake rod. At least one device is provided for locking the frame tubes and the parallel rods.