Abstract: A tennis training apparatus comprises a balanced rod having an upper segment, mid-section, and lower segment. One or more of the training apparatuses may be secured separately along a tennis net tape with the upper segment extending above the tape as a target. When struck by a tennis ball, the upper segment pendulums back and forth while providing a ringing sound. The upper segment is further divided into a plurality of regions which correlate to different sections of a tennis racket. The training apparatuses may be moved to desired locations along the net tape to create different targets, gaps, and spacings for the players to practice all tennis skills during practice matches or drills. A stand-alone version of the training apparatus need not be attached to a tennis net, but pivots on a stand which provides adjustable pendulum motion, and can be utilized for a variety of non-tennis training exercises.

Abstract: Low cost, durable, reusable, lightweight, inexpensive, simple, easy to assemble/disassemble, transportable goal posts. Each goal posts may be composed of single piece T reinforcements and a single piece cross bar reinforcement, as well as readily available construction materials, such as PVC pipe. The bodies of the single piece reinforcements are sized so that the pipes forming the upright posts and crossbar have the same length. Assembly, disassembly, and transportation are simplified. The disassembled components can be carried in vans and SUVs. Internal reinforcements allow flexible, low cost materials such as PVC pipe to be used while maintaining a professional, aesthetic appearance.

Abstract: A lacrosse head pocket includes an elongated single layer runner with multiple cross pieces. The single layer runner can be constructed from a material, such as a polymeric material, molded over the cross pieces. The cross pieces and/or runner can include speed lace loops with which a net lace can be joined. A related method includes providing cross pieces, overmolding a polymeric material over the cross pieces to form a single layer runner, where the overmolded material is the only structure extending between and connecting the cross pieces, and where the cross pieces are transverse to the runners. Another method includes providing a pocket base overmolding the base with a polymeric material to cover portions of it, and forming connection elements between different portions independently of any other components of the pocket base.

Abstract: A lacrosse head pocket includes an elongated single layer runner with multiple cross pieces. The single layer runner can be constructed from a material, such as a polymeric material, molded over the cross pieces. The cross pieces and/or runner can include speed lace loops with which a net lace can be joined. A related method includes providing cross pieces, overmolding a polymeric material over the cross pieces to form a single layer runner, where the overmolded material is the only structure extending between and connecting the cross pieces, and where the cross pieces are transverse to the runners. Another method includes providing a pocket base overmolding the base with a polymeric material to cover portions of it, and forming connection elements between different portions independently of any other components of the pocket base.

Abstract: A protective strip device to apply to the shaft of a hockey stick, the strip device having an inner side face, adhesive on the inner side face for bonding to the shaft of the stick, an outer facing side defining a central groove, and two spaced apart shock absorbing side abutment ridges extending lengthwise along opposite sides of the central groove, and a plurality of spaced apart openings formed along the central groove.

Abstract: Rubber sheets of various compounds are glued to the outer surfaces of pickle ball paddles made of plastic, wood, fiberglass, aluminum or graphite.

Abstract: A projectile can be fired at a surface vessel and, upon impact, an air bag may be deployed almost instantaneously from underneath the vessel. Through the rapid inflation of the air bag, the stability and orientation of the target surface vessel may be disturbed. Disturbance, at a minimum, may reduce and change the trajectory of the surface vessel, but, in some circumstances, the surface vessel may be overturned. The air bag may be designed with an anti-slip coating to directly couple to the wet hull of the surface vessel. In some embodiments, the projectile may include a delay to enable the air bag to be positioned under the vessel before inflation thereof.

Abstract: A fletching system and method that allows for quick and easy attachment of a fletching member to an arrow or cross bolt shaft provides a slotted fletch holder adapted to receive a fletching member projecting therethrough and an external end cap member to provide frictional fit engagement with a flanged base portion of the fletching member wherein the flanged base portion is secured between the end cap member and an internal surface of a sidewall of the fletch holder.

Abstract: A baseball or softball comprising a cover having an outer surface that is formed of a first material. A second material that is easier to grip than the first material is affixed to the cover in the same location as the seam on a conventional baseball or softball. The ball's outer surface is molded and stitchless, meaning that the outer covering is not made by stitching panels together. While the ball may be stitchless, it may have simulated, molded stitches. The second material, when positioned on a planar surface, comprises a continuous strip having two generally semicircular ends each integral with a pair of opposed concave sides (e.g. a FIG. 8 configuration).

Abstract: The V-belt continuously variable transmission comprises a driving pulley and a driven pulley mounted on shafts, each of which pulleys consists of two half pulleys movable in a horizontal plane and provided with radial longitudinal through slots for enabling the half pulleys to mate (penetrate) one another, and a drive belt. Furthermore, each half pulley is in the form of a single component consisting of three solids of revolution with a common axis, which are interconnected as a single unit, two of said solids of revolution being different-sized hollow truncated cones oriented in different directions and connected by their smaller bases, and the third being a hub that is connected to the corresponding shall in such a way as to be able to move along the latter. The technical result of the claimed utility model is enhanced reliability and increased service life.

Abstract: A polygon compensation coupling system for reducing a polygon effect in a chain driven system is disclosed. The polygon compensation coupling system may include a chain sprocket and a main drive in engagement with the chain sprocket, such that the engagement defines a compensation curve to reduce the polygon effect.

Abstract: A cover for protecting a drivetrain system, which is used when a bicycle is stowed in a carrying bag, is disclosed. The chain bag is a rectangular bag with two hanging belts. The hanging belts are separately disposed with velcro fasteners for hanging on a frame or rack of a bicycle.

Abstract: A sprocket box for increasing the gas mileage of a vehicle with an automatic transmission is positioned between the back of an engine block and the torque converter. The sprocket box is fed the rotational motion from the engine and doubles the rotational motion being fed into the torque converter in order to increase the fluid pressure felt within the torque converter. Thus, the sprocket box is used to increase the fuel economy of the vehicle. The rotation motion from the engine is transferred and modified by the sprocket box by using an input assembly of sprockets and a roller chain and by using an output sprocket of more sprockets and another roller chain.

Abstract: A chain, wound to span between two pulleys each having facing conical surfaces able to change a distance therebetween and sandwiched by the facing conical surfaces, includes: link units each configured such that plate-shaped links, each having openings, are oriented in a chain circumferential direction and arranged in a chain width direction; and pins each extending through the openings of the links of the link units adjacent in the chain circumferential direction and each contacting the conical surfaces of sheaves at both ends thereof. A curvature radius of a shape curve representing a shape of each end face of each pin in a plane perpendicular to the chain circumferential direction is larger at an inner side in a pulley radial direction than at an initial contact point that is a contact point at the time when a load on each pin is 0.

Abstract: The durability of a frictional power transmission belt is improved. A V-ribbed belt (10) comprises an adhesion rubber portion (12) and a compression rubber portion (14) provided below the adhesion rubber portion (12). A cord (11) that is a tension member of the belt is embedded in the adhesion rubber portion (12). The adhesion rubber portion (12) includes an upper layer (12A) constituting the upper side and a lower layer (12B) constituting the lower side, which are located across the cord (11). The upper layer (12A) and the lower layer (12B) are obtained by vulcanizing a rubber composition including a high-viscosity elastomer such as EPM or EPDM, and a low-viscosity elastomer which is lower in Mooney viscosity than the high-viscosity elastomer, and contain modified nylon microfibers as short fibers (21A), (21B), respectively. The short fibers (21A), (21B) are oriented, respectively, in the width direction and longitudinal direction of the belt.

Abstract: A planetary transmission of a wind turbine includes a ring gear which has an internal toothing and at least one planetary gear which has an external toothing that meshes with the internal toothing of the ring gear. The planetary gear is rotatably supported on an axle by a bearing assembly. The bearing assembly includes at least one outer ring having a radially-outwardly-protruding radial projection and at least one set of rolling elements that roll on the outer ring. The planetary gear has a bore and a recess in the region of an axial end, which recess widens the bore. The outer ring is disposed in the bore of the planetary gear such that the radial projection of the outer ring engages into the recess of the planetary gear.

Abstract: The invention relates to rotary units and rotary mechanisms that are suitable for use in numerous applications. Rotary units typically include rotational components that are configured to rotate. In some embodiments, for example, multiple rotary units are assembled in rotary mechanisms such that neighboring pairs of rotational components counter-rotate or contra-rotate relative to one another during operation of the rotary mechanisms. Rotational components generally include one or more implements that are structured to perform or effect one or more types of work as the rotational components rotate relative to one another in a given rotary mechanism. In certain embodiments, implements are configured to rotate and/or to effect the movement of other components as rotational components rotate. In some embodiments, engines include rotary mechanisms and are used in, for example, ground vehicles, marine vehicles, aircraft, or devices.

Abstract: A transmission device or an electric axle which has improved operational characteristics compared to known solutions. Said aim is achieved by providing a transmission device (1) including an electric motor (3) provided with a rotor (6), a planetary gear (4) provided with at least one sun gear (9), and a shaft arrangement (7,8), the rotor (6) being coupled in a rotationally fixed manner to the sun gear (9) by the shaft arrangement (7, 8). The shaft arrangement (7,8) includes at least one compensation interface (21) which is designed such that it is possible to change the distance and/or tilting between the motor (6) and sun wheel (9).

Abstract: The present invention relates to a drive device for a vehicle with an electric motor, for which at least a drive motor is utilized as a drive source, and the drive motor and a drive wheel are connected by means of a constant velocity universal joint. The drive device is provided with a drive motor. A drive shaft is connected to the drive motor via an inboard joint. The inboard joint is housed at the inner periphery section of the drive motor. An outer cup, a constituent of the inboard joint, is provided with a guide race on the inner periphery section in order for a roller member to slide. The outer periphery section of the outer cup is rotatably supported by the inner periphery section of the drive motor.

Abstract: An apparatus for multiplexing gear engagement control in an automatic transmission is provided. At least two friction engagement devices are configured to selectively engage and disengage a different gear ratio of the transmission. A trim system is configured to selectively supply engagement and disengagement pressures to at least one fluid passageway. A first control valve is fluidly coupled directly to the at least one fluid passageway and directly to each of the at least two friction engagement devices. The first control valve is configured to selectively route the engagement and disengagement pressures through the first control valve directly to the at least two friction devices.

Abstract: A hybrid electric drive system for a hybrid powered vehicle which includes a combustion engine, and a transmission. An electric machine and the combustion engine are coupled to the transmission in the hybrid electric drive system providing engine and/or electric machine drive power for the vehicle. A clutch is mechanically communicating with and positioned between the combustion engine and the transmission to decouple the combustion engine from the transmission. An energy storage system is configured to transfer and receive power with the electric machine, and is configured to recharge using power from the electric machine. A hybrid system controller is configured to respond to a regenerative braking mode of the vehicle. While the hybrid electric drive system is in the regenerative braking mode, the hybrid system controller is configured to initiate shifting of the transmission into one or more selected gears relating to one or more selected electric machine speeds.

Abstract: A gear shift control system for vehicles is provided which mathematically calculates a rate of deceleration of the vehicle equipped an automatic transmission upon start of deceleration of the vehicle and inhibits the automatic transmission from upshifting or changes a permissible gear shift range of the automatic transmission as a function of the rate of deceleration of the vehicle, thereby ensuring a desired degree of braking force including an engine braking force while the vehicle is decelerating.

Abstract: A driving force transmission apparatus includes a linkage mechanism that is able to carry out switchover between a connected state where first and second intermediate shafts are connected to each other so as to be non-rotatable relative to each other to transmit torque output from an electric motor to a rear wheel, and a disconnected state where the first and second intermediate shafts are disconnected from each other. When switching the driving force transmission apparatus from the connected state to the disconnected state, a control unit reduces the torque that is generated by the motor during a drive state where the torque output from the motor is transmitted from the first intermediate shaft to the second intermediate shaft, and switches the driving force transmission apparatus from the connected state to the disconnected state by controlling the linkage mechanism while the torque that is generated by the motor has been reduced.

Abstract: A driving force transmission apparatus includes a linkage mechanism that is able to carry out switchover between a connected state where a first intermediate shaft and a second intermediate shaft are connected to each other so as to be non-rotatable relative to each other to transmit torque output from an electric motor to a rear wheel, and a disconnected state where the first intermediate shaft and the second intermediate shaft are disconnected from each other. A control unit reduces the torque that is generated by the electric motor, after making a rotational speed of the first intermediate shaft higher than or equal to a rotational speed of the second intermediate shaft, and then switches the driving force transmission apparatus from the disconnected state to the connected state by controlling the linkage mechanism with the torque that is generated by the motor maintained at a reduced level.

Abstract: A vehicle steering system includes: a steering wheel having the capacity to steer a vehicle; a turning actuator having the capacity to turn a wheel; a backup clutch arranged between the steering wheel and the turning actuator and having the capacity to be able to mechanically connect the steering wheel to the turning actuator; and a clutch disengagement checking unit having the capacity to check whether the backup clutch is disengaged.

Abstract: A vehicle is provided with an engine that is configured for automatic shutdown and restart. The vehicle is also provided with a controller that is configured to shutdown the engine in response to brake effort exceeding a first threshold and to restart the engine in response to brake effort decreasing below a second threshold. The first threshold and the second threshold are based on an estimated vehicle mass and a road gradient.

Abstract: A vehicle includes an engine configured for automatic shutdown and restart. The vehicle is provided with a controller that is configured to restart the engine when a difference between an actual brake pressure and a filtered brake pressure is greater than a threshold value. The filtered brake pressure is dependent upon a magnitude of the actual brake pressure and a rate of change of the actual brake pressure.

Abstract: A system and method for controlling a tension in an exercise apparatus are provided. The system includes an input/output (I/O) subsystem for permitting a user to enter at least one resistance value and for displaying a resistance exerted by the exercise apparatus; a controller configured to control the tension of the exercise apparatus based on the at least one resistance value entered by the user adjusting a position of a holder and moving a plurality of guides for selective attachment of tension members to catches on the exercise apparatus; and a power source connected to the controller and the I/O subsystem and configured to power the controller and the I/O subsystem.

Abstract: The present invention relates to a therapeutic oral exercise apparatus for strengthening the tongue. The device is a water-filled unit comprised of clear tube with two bulbs on each end. The exerciser is activated in the mouth by pressing the pressurized bulb with the tongue against the hard palate. A floating indicator in the tube offers visual feedback and elevates as the tube is compressed. The device is adjustable in difficulty. The presenting invention is simple in design and operation. It has limited moving or articulating parts, requires no customization, is non-electrical, can be operated with one hand and is inexpensive to manufacture. The Tongue Press Oral Exerciser is an affordable means of strengthening swallowing and speech intelligibility.

Abstract: A trampoline which is reliable and efficient in use, and which does not require extension springs to secure the jumping mat to the frame. The trampoline may maintains the traditional feel of a trampoline more satisfactorily than presently known soft edged trampolines. The trampoline may also be efficiently manufactured.

Abstract: The invention discloses a trampoline, including spring mattress (1), legs (2), rails (3). Said foot tube (2) mounted on the spring pad (1) the lower end, said rails (3) disposed in a spring mattress (a) top. Characterized in: The fence (3) constitutes side rod (4)surrounded by a set spring mattress (1), the support rod (4) to connect the barrier ring (5) and connected to the fence ring (5) on the protection net (6). The rod (4) from the previous section elbow (41) and the lower section straight tube (42) sockets with each other. There are holes on the bent upper section (41). By this hole the protective net (6) and the barrier ring (5) is connected. The device has a larger sport area, structural stability, easy to disassemble, high safety factor, long life and other characteristics.

Abstract: An swing handle arrangement for an exercise equipment wherein a pair of the drive rods driven by the pedal-connecting rods is employed such that the pivot shaft mounted on the front support conducts a synchronous swing. Moreover, two swing handles fitted with a mating toothed member are pivotably connected to the top of the drive rods. Thereafter, toothed members are secured to the front support and meshed with the mating toothed member of the swing handles. A waist-twisting movement of the upper body can be synchronically achieved when the operator holds on the swing handles to take exercise at his feet of the lower body.

Abstract: An exercise device having multiple components that are lightweight and easily storable is described and taught. The exercise device is a platform that may have a non-slip surface. The individual components may include fitness blocks, resistance bands, balance arches, and rollers. Theses components may be used singularly or in conjunction with one another. This allows a user to perform a number of exercises including strength training and resistance training along with other aerobic and anaerobic exercises. When not in use, these components store underneath the platform in designated recesses. In some cases, there is a lid or covering for any number of the recesses. The device, as a whole, is lightweight, portable and easily used in small spaces creating an ideal workout device.

Abstract: A rehabilitation treadmill includes a running belt, a plurality of pace sensors mounted to two opposite sides of the running belt, and a control panel. When a user intends to do rehabilitation exercise via the rehabilitation treadmill, the pace sensors can detect the user's footstep to generate and transmitting an activation signal and a stop signal to the control panel and then the control panel can activate or stop the running belt subject to the activation or stop signal. In this way, the user can repeatedly put his or her feet on running belt alternately to effectively have the rehabilitational effect.

Abstract: Provided are a bike trainer, and an exercise apparatus with a bike trainer for supporting a bike on a treadmill. A mounting bracket is adapted to be non-invasively installed on a frame of the treadmill utilizing a releasable fastener that is adjustable to secure an installation of the mounting bracket and allow the mounting bracket to be removed from the frame. A plurality of arms are coupled to the mounting bracket and each include a distal end to be positioned at an elevation vertically above an elevation of the belt of the treadmill. A bike coupler is provided adjacent to the distal end of at least one of the arms, and is adapted to cooperate with a portion of the bike to couple the bike to the bike trainer apparatus and maintain the bike over the belt of the treadmill.

Abstract: A ski training device includes a frame and two sets of rollers mounted side-by-side on axles on the frame. The two sets of rollers each define a linear roll path and a roll surface. Each roll path has a rearward portion, a central portion, and a forward portion, and the two roll paths are substantially parallel. Each roll surface similarly has a rearward portion, a central portion, and a forward portion, and the rearward and forward portions of each roll surface are higher than their respective central portions when the ski training device is positioned on a flat, level surface. Each roll surface accordingly arcs or slopes upward as one moves forward or rearward along the roll path from its center, thus helping to keep a skier centered over the rollers when training.

Abstract: A wooden dummy includes a body and a stand assembled to the body. The body has an outer circumferential surface divided into three equal zones oriented to three different directions. The three zones are respectively provided on a higher portion at a different height with a set of arm holes, into which three arm rods can be inserted for use as means to practice hand striking, blocking and so on. The stand is formed from three angled legs of different heights and orientations. The legs are located in the three zones at a lower portion thereof corresponding to the sets of arm holes in orientation and height, and can be used for practicing leg raising and kicking. Thus, one single wooden dummy can be flexibly used by one or more users of different heights.

Abstract: An exercise apparatus includes a frame having a lower support member, an upper support member and a pair of horizontal support members. The lower support member is secured to a base and includes an extension mechanism for raising and lowering the frame. The frame further including a support member and a pair of angled support members operably secured to the frame for supporting a plurality of target pads, each of the target pads positioned to assist a user in executing punches.

Abstract: A training bag comprising a bag removably attached to a base, where the bag may be a foam cylinder with a cover and the base may be pre-filled with sand. The bag may attach to the base via hook and loop material. The training bag may be used for all standing strikes, high and low, as well as for ground work, and requires no assembly and no installation.

Abstract: An inertial dumbbell exercise device including a first and second weight assembly disposed endwise upon a handle, each of said weight assemblies including a rod disposed perpendicularly and slidably upon the handle, an interchangeable pair of weights disposed endwise upon said rod, and an interchangeable rubber sleeve disposed between each of said pair of weights and said handle, wherein movement of the handle in a first direction accelerates one of said pair of weights from a first position to a second position against the elastic force of the respective rubber sleeve, movement of the handle in a second and opposite direction accelerates the other of said pair of weights from a first position to a second position against the elastic force of the respective rubber sleeve, and the compressive resistance of the rubber sleeve is adjustable, as desired.

Abstract: The present invention relates to a structure of exercise cord, which includes at least one elastic cord having two ends of which at least one is provided with a grip. The grip has two ends at top side extending between which is a handhold and a base seat is provided at the side opposite to the handhold. The base seat forms three retainer seats that extend through a bottom of the base seat. Each of the retainer seats has an upper end forming a circumferential recess and including therein a clamp extending to middle of the retainer seat. Three anchoring plugs are each provided with a retention rim at an upper end thereof and forming a cord extension hole in a lower end and also including a coupling section formed on a side thereof. The three anchoring plugs are respectively receivable in the thee retainer seats.

Abstract: Physical therapy devices, including vertically extending rear support structures, arm pivots supported by rear support structures at positions vertically spaced from supporting surfaces, arms pivotally supported by the arm pivots, seats resting on the arms at distances selected to apply portions of users' bodyweights the arms when the user is seated in the seat, foot rests supported above supporting surfaces at heights selected to support a forward portion of the user's foot when the user is seated in the seat, and knee saddles attached to the arms. In some examples, the knee saddles including a knee support positioned at a height selected to rest on the user's knee when seated in the seat. In some examples, the arms extend horizontally from a pivot end to a swing end distal the arm pivot. Some examples may additionally or alternatively include adjustably positioned arm pivots. Some examples may include biasing members.

Abstract: Weight lifting strap which is looped around the wrist and wrapped in helical fashion about a weight lifting bar or the like and gripped by the hand with opposite sides of the strap facing the bar and the hand, and the strap being fabricated of a woven material with rubberized strands on the side of the strap which faces the bar.

Abstract: An apparatus including a first and second closed loop, and a first strap connected to the first closed loop and the second closed loop, between the first closed loop and the second closed loop. Each of the first closed loop, the second closed loop, and the first strap may be made of a substantially inelastic material, such as a resilient cloth material. The first strap may have a first end which is connected to the first closed loop and the second closed loop; and the first strap may have a second end, which is opposite the first end, and which is connected to a third closed loop. The first strap may be connected to a bed, a first and second foot of a person can be inserted into the first and second closed loop, respectively; and exercises can be performed while on the bed.

Abstract: Method of doing pushups employs a pair of pushup devices including at least one retainer for receiving a connection member at an end of an exercise band; an elastic exercise band is connected to a retainer of each push up device with the band over a user's back as a user pushes upwardly on the handle sections of the pushup devices. A pushup device also constitutes a part of the invention. The pushup device includes a longitudinally extending passage at the lower end of a body section in which an end section of an elastic exercise band is directed when a pushup in accordance with this invention is being carried out. Preferably the pushup device includes a handle section removable from a body section and usable with one or more elastic exercise bands separately from the body section to provide a variety of different exercises other than pushups.

Abstract: An exercise machine is provided for a user performing squats. A base supports the exercise machine, and an upright member having a free end and an attachment end is mounted to the base at the attachment end and configured to be straddled by the user. A leg pad assembly is adjustably attached to the upright member for vertically adjusting a height of the leg pad assembly. The leg pad assembly has a first leg pad member extending horizontally relative to the upright member and configured to engage a back of the user's legs. A locking mechanism is provided for selectively releasably securing the leg pad assembly in a desired position on the upright member.

Abstract: An exercise machine for supporting a user during exercise includes a base and a platform assembly coupled to the base. The base is adapted to be supported on a floor and the platform assembly is mounted to the base so that the platform is supported above the floor. The platform assembly is configured to support a user performing an exercise.

Abstract: A hand power tool includes a tool receiver configured to receive a tool. The tool has an outer polygonal coupling and the tool receiver has an inner receiver including, at least portionally, a rotary driver profile. The tool receiver is provided on an associated tool housing, in which there is a drum-type tool change magazine having at least one tool chamber configured to store the tool. The tool chamber is configured to be aligned so as to be flush with the tool receiver to enable the tool to slide from the tool chamber into the inner receiver or from the inner receiver into the tool chamber. An alignment element is configured to align the outer polygonal coupling as the tool slides from the tool chamber into the inner receiver to enable the outer polygonal coupling to slide into the rotary driver profile.

Abstract: In a bearing arrangement (A) of a rotating brush roller (1), wherein the brush roller (1) is arranged by outwardly located end pieces via a bearing (10) in a support arrangement (9) of a brush housing (15), and the brush roller (1) (comprises) a spiral-shaped receiving shaft with an outwardly located through passage area for receiving and retaining a continuous brush strip (2) as well as an end face opening for provision and removal, it is provided that the outer area is covered by a closure part. In this regard, the closure part has a releasable sub-element (5) as a continuation part of the support arrangement (9), which uncovers an end face opening to the receiving shaft to the brush strip (2). The sub-element (5) is releasably fixable by a catch element (4) for a corresponding unlockable counter support (13) in the brush housing (15), and for forming a thread deflector has a deflector element (7) of metal in continuation of a stationary deflector element (11) of the closure part.

Abstract: The invention relates to a folding blade for a blown film line, as well as to a blown film line equipped therewith. Folding blades are used for laterally folding in a film bubble running to the take-off pinch rolls. If they engage deeply into the film bubble, they are provided with a fin on the rear side, and referred to as deep folding blades. The invention proposes that the rear side of a folding blade be equipped with a fin, which exhibits a collapsible element with an adjustment device. The volume of the fin can thereby be varied. In particular, the fin can be laid flat against the rear side of the folding blade.