NZ788764A - Hand-held tamping machine for compacting track ballast - Google Patents

Abstract

assist users of hand-held tamping machines, vibration dampeners a have been used. Such dampeners do not completely cancel out the vibrations transmitted to the handles. Further, such machines are quite noisy and the exhaust emissions can adversely affect users. To address these issues the present invention provides a hand-held tamping machine (1) for compacting track ballast (2) includes a tamping pick (5) for penetrating the track ballast (2), a vibration generator for vibration excitation of the tamping pick (5), a motor (7) which is connected with the vibration generator via a drive shaft, a handle device (8) having at least one handle (17a, 17b) for steering the hand-held tamping machine (1) during operation, wherein along a shaft axis (16) of the drive shaft the at least one handle (17a, 17b) is arranged above the machine center of gravity (SP0) of the hand-held tamping machine (1) by at least 30 % of the overall height (H) of the hand-held tamping machine (1) and/or is arranged above the motor center of gravity (SPM) of the motor (7) by at least 15 % of the overall height (H) of the hand-held tamping machine (1). The invention has provided higher inertial damping, and positions a user’s head away from noise and exhaust fumes. invention provides a hand-held tamping machine (1) for compacting track ballast (2) includes a tamping pick (5) for penetrating the track ballast (2), a vibration generator for vibration excitation of the tamping pick (5), a motor (7) which is connected with the vibration generator via a drive shaft, a handle device (8) having at least one handle (17a, 17b) for steering the hand-held tamping machine (1) during operation, wherein along a shaft axis (16) of the drive shaft the at least one handle (17a, 17b) is arranged above the machine center of gravity (SP0) of the hand-held tamping machine (1) by at least 30 % of the overall height (H) of the hand-held tamping machine (1) and/or is arranged above the motor center of gravity (SPM) of the motor (7) by at least 15 % of the overall height (H) of the hand-held tamping machine (1). The invention has provided higher inertial damping, and positions a user’s head away from noise and exhaust fumes.

Description

To assist users of hand-held tamping es, vibration dampeners a have been used. Such dampeners do not completely cancel out the vibrations transmitted to the handles. Further, such machines are quite noisy and the exhaust emissions can adversely affect users. To address these issues the present invention provides a hand-held tamping machine (1) for compacting track ballast (2) includes a tamping pick (5) for penetrating the track ballast (2), a ion generator for vibration excitation of the g pick (5), a motor (7) which is connected with the ion generator via a drive shaft, a handle device (8) having at least one handle (17a, 17b) for steering the hand-held tamping machine (1) during operation, wherein along a shaft axis (16) of the drive shaft the at least one handle (17a, 17b) is arranged above the machine center of gravity (SP0) of the hand-held tamping machine (1) by at least 30 % of the overall height (H) of the hand-held tamping machine (1) and/or is arranged above the motor center of gravity (SPM) of the motor (7) by at least 15 % of the overall height (H) of the hand-held tamping machine (1). The invention has provided higher al damping, and positions a user’s head away from noise and exhaust fumes.

NZ 788764 Hand-held tamping machine for compacting track ballast The present patent application claims the priority of German patent application DE 10 2021 205 469.2, filed on 28 May 2021, the contents of which are incorporated herein by reference.

Technical field The invention relates to a hand-held tamping machine for compacting track ballast.

Background A hand-held tamping machine for compacting track ballast is known from tamping pick for penetrating the track ballast, a vibration generator, a combustion motor for driving the vibration generator in rotation, and handles for steering the hand-held tamping machine during operation.

Vibration dampers act between the vibration generator and the handles.

However, the vibrations itted to the handles cannot be tely cancelled out and are stressful for the user. Noise and exhaust ons generated by the combustion motor are an additional burden for the user.

The above discussion of background art is included to explain the context of the present invention. It is not to be taken as an admission that any of the documents or other material ed to was hed, known or part of the common general knowledge in Australia at the priority date of any one of the claims of this specification.

Throughout the description and claims of this specification, the word “comprise” and variations of that word, such as “comprising” and “com- prises” are not intended to e other additives, steps or integers.

Summary of the ion A desirable outcome of the present invention is to improve a hand-held tamping e for compacting track ballast, in particular to se its ease of use and to reduce the stresses it imposes on the user.

Accordingly, in one aspect the invention provides a hand-held tamping machine for compacting track ballast, having - a tamping pick for penetrating the track ballast, - a vibration generator for vibration excitation of the tamping pick, - a motor which is connected with the vibration generator via a drive shaft, - a handle device having at least one handle for ng the handheld tamping machine during operation, wherein along a shaft axis of the drive shaft, the at least one handle - is arranged above a machine center of gravity of the hand-held tamping machine by at least 30 % of an overall height of the handheld tamping machine and/or - is arranged above a motor center of gravity of the motor by at least 15 % of the overall height of the hand-held tamping machine.

According to the invention, it has been found that a hand-held g machine has a particularly high ease of use if, along a shaft axis of a drive shaft connecting the motor to the vibration generator, at least one handle for steering the hand-held tamping machine is arranged above the machine center of gravity of the hand-held tamping machine by at least 30 % of the overall height of the eld tamping machine and/or is arranged above the motor center of gravity of the motor by at least 15 % of the overall height of the hand-held tamping machine. The arrangement of the at least one handle above the motor center of gravity has the effect that the user's head can be kept particularly far away from the noise and/or pollutant producing motor. It is true that the motor is closer to the vibration generator due to its low-lying ement. Surprisingly, however, it has been found that this does not necessarily subject the motor to higher vibration loads. On the contrary, the arrangement closer to the machine center of gravity may result in higher inertial damping, which may even reduce the vibrations transmitted to the motor.

The lower e center of gravity with respect to the at least one handle facilitates the steering of the eld tamping machine. In order to tamp the track ballast under a track sleeper, the hand-held tamping machine penetrating the track ballast is ed about a horizontal axis. It is true that a corresponding swiveling motion of the hand-held tamping machine from the vertical orientation is supported by a high machine center of gravity. However, it has been found that the mass to be moved by the user, and thus the total energy to be applied by the user, can be reduced by the lower machine center of gravity, thus causing the user to fatigue less quickly. Furthermore, the longer lever arm provides better control over the hand-held tamping machine with respect to the machine center of gravity.

A particular age of the hand-held tamping machine according to the invention is that the vibrations prevailing at the at least one handle during operation and the associated stresses on the user are particularly low. Due to the particularly low arrangement of the machine center of y with respect to the at least one handle, a vibration nodal point of a rigid-body ion excited by the vibration generator can be displaced to be particularly close to the at least one . At the at least one handle, the resulting vibration amplitude is thus particularly low. Circulatory ers and muscle diseases associated with continuous vibration stress can thus be prevented.

In connection with position and dimension specifications, reference is made to the main orientation of the hand-held g machine during operation, in which the drive axis is oriented ally. In this operating state, the tamping pick points downwards in the vertical direction.

Distances with respect to the at least one handle are measured to the upper side of the handle, unless otherwise specified. The shaft axis is preferably arranged coaxially to the central longitudinal axis and/or to the vertical axis of the hand-held tamping machine. The machine center of gravity is understood to be the center of gravity of the hand-held tamping machine, in particular in a ready-to-use state of the hand-held tamping machine. In this state, for e, a fuel tank of the motor is half-filled and a ballast contact attachment, which is preferably construed to be exchangeable, is attached to the hand-held tamping machine. Steering the hand-held tamping e in operation is understood to mean holding and displacing the hand-held tamping machine while compacting the track ballast and/or carrying the eld tamping machine to the position of the track t to be sed. The term "above" refers in particular to the direction towards the at least one handle.

The handle device preferably has at least two, in particular exactly two, or at least three, in particular at least four, of the handles. Preferably, the position specifications made in connection with the at least one handle apply to all of the handles. The at least one handle may be formed by a carrying structure and/or attached o. Preferably, the tive handle comprises a vibration-damping material, in particular a c material and/or a rubber-elastic material. A power adjustment element, in particular a throttle lever, for regulating the power output by the motor can be ed at the at least one handle, in particular such that the user does not have to release the hand from the handle to actuate the power ment element. ably, the tamping pick comprises an attachment support and a ballast contact attachment that can be detachably attached to the attachment support. The ballast t attachment, which is subjected to high stresses as a result of contact with the track ballast, can thus be easily replaced.

The tamping pick, in particular the attachment support, is preferably configured so as to be hollow, in particular tubular. The attachment support may be configured as a tamping pick tube. ing to one aspect of the invention, the vibration generator is arranged at least in sections within the tamping pick tube or tubular tamping pick. An imbalance mass of the vibration tor may be completely arranged within the tamping pick tube and/or completely overlapped by the g pick tube along a direction perpendicular to the shaft axis.

The ion generator is preferably ured such that the forces generated for the vibration excitation of the tamping pick act so as to be perpendicular to the shaft axis, in particular in the horizontal direction. The transmission of vibrations oriented as to be perpendicular to the shaft axis to the at least one handle and/or the motor is particularly strongly inhibited in the hand-held tamping machine according to the ion.

Following one after the other in the vertical direction, the hand-held tamping machine preferably comprises the at least one handle, the motor center of gravity, the machine center of gravity, and a tip of the tamping pick. A vibration nodal point can thereby be arranged along the shaft axis particularly close to the at least one handle.

Preferably, the overall height of the eld tamping machine and/or the distance between the at least one handle and the underside of the tamping pick are in a range from 850 mm to 1250 mm, in particular from 950 mm to 1150 mm, in particular from 1000 mm to 1100 mm.

In one preferred embodiment, a hand-held tamping machine configured such that along the shaft axis the at least one handle is arranged above the e center of gravity by at least 40 % of the overall height of the handheld tamping machine is particularly operator-friendly. The vibrational motions transmitted to the at least one handle are r d. The hand-held tamping machine is even easier to steer during operation. The machine center of gravity, in particular along the shaft axis of the drive shaft, is preferably arranged in a range from 30 % to 70 %, in particular from 35 % to 65 %, in particular from 40 % to 60 %, in particular from 45 % to 55 %, of the overall height of the hand-held tamping machine below the at least one handle, in particular below all handles.

Preferably, a hand-held tamping machine configured such that along the shaft axis the machine center of gravity is arranged at a maximum of 60 % of the overall height of the hand-held g machine below the at least one handle has a ularly high ease of use. Due to the arrangement of the machine center of gravity at a m of 60 % of the overall height of the hand-held tamping machine below the at least one handle, the vibrations itted to the at least one handle are particularly low due to inertial damping by the machine mass. Along the shaft axis of the drive shaft, the at least one handle is preferably arranged above the machine center of gravity by a m of 65 %, in particular a maximum of 60 %, in particular a maximum of 55 %, in particular a maximum of 50 %, in particular a maximum of 45 %, of the overall height of the hand-held tamping machine. Along the drive shaft, the at least one handle is preferably arranged by a maximum of 50 %, in particular a maximum of 45 %, in particular a maximum of 40 %, in particular a maximum of 35 %, in particular a maximum of 30 %, in particular a m of 25 %, above the motor center of gravity of the motor. As a , a particularly high ease of use can be achieved.

In on preferred embodiment, a hand-held tamping machine configured such that along the shaft axis the at least one handle is arranged above the motor center of gravity by at least 20 % of the overall height of the eld tamping machine is particularly operator-friendly. Due to the arrangement of the motor center of gravity far away from the at least one handle, the user is less intensely exposed to noise and/or t emissions. Vibrations which emanate from the motor are transmitted less strongly to the at least one handle due to the greater proximity to the machine center of gravity and the resulting greater inertial damping. Preferably, the motor center of gravity is arranged along the shaft axis in a range from 15 % to 50 %, in particular from 20 % to 40 %, in particular from 25 % to 30 %, of the l height of the hand-held tamping machine below the at least one, in particular all, handles.

Preferably, a hand-held tamping machine configured such that along the shaft axis a ce between the at least one handle and a vibration nodal point of the hand-held g machine due to the vibration excitation by the vibration tor is a maximum of 15 % of the overall height of the hand-held tamping machine has a particularly high ease of use. The stress on the user caused by vibrations transmitted to the at least one handle is particularly low. The vibration nodal point is preferably one, in particular the only, vibration nodal point of a rigid-body motion of the hand-held tamping machine caused by the vibration excitation of the vibration tor. Alternatively, this may be a vibration nodal point due to an elastic deformation of the hand-held tamping machine and/or an inherent mode of ion of the hand-held tamping machine. The at least one handle is arranged along the shaft axis preferably at a maximum distance of %, in particular at a maximum distance of 10 %, in particular at a maximum ce of 5 %, of the overall height of the hand-held tamping machine from the vibration nodal point.

According to another aspect of the invention, the motor center of gravity is arranged along the shaft axis at a maximum ce of 15 %, in ular at a maximum distance of 10 %, in particular at a maximum distance of 5 %, of the overall height of the hand-held tamping machine from a vibration nodal point of the hand-held tamping e due to vibration excitation by the vibration generator. As a result, the vibration loads itted to the motor can be reduced.

In one preferred embodiment, a hand-held tamping machine configured such that the vibration nodal point is caused by a rigid-body motion and/or an elastic deformation of the hand-held tamping machine has a particularly high ease of use. The stress on the user caused by vibrations transmitted to the at least one handle is particularly low. In particular, the vibration amplitude excited during operation of the hand-held tamping machine in the region of the at least one handle is especially low. The vibration nodal point is preferably detected in an operating state of the hand-held tamping machine in which no external forces act on the hand-held tamping machine and/or when the tamping pick has penetrated the track ballast and/or when the tamping pick, in particular a tip of the tamping pick, is fixed, in particular fixed in position and/or fixed in ation.

Preferably, a hand-held tamping machine including a first vibration ler which acts between the tamping pick and the handle device and/or the motor has a particularly high ease of use. The first vibration decoupler preferably comprises a vibration damper. The first vibration decoupler may have, in particular for connecting the handle device and/or the motor with the tamping pick and/or the vibration generator, at least one decoupling element, in particular an elastic t and/or a damping element, in particular a rubber-elastic body. Preferably, the first vibration decoupler acts n the handle device and/or the motor and the g pick and/or the vibration generator and/or between the handle device and the motor. According to one aspect of the invention, the first vibration decoupler enables limited relative movement n the handle device and/or the motor and the tamping pick and/or the vibration generator and/or between the handle device and the motor in a horizontal direction and/or in a vertical direction. This allows the at least one handle and/or the motor to be decoupled from a vibration of the tamping pick and/or the vibration generator.

In one preferred embodiment, a hand-held tamping machine ured such that a handle-side tion point and/or a tamping-pick-side connection point of the first vibration decoupler are arranged above the machine center of gravity has a particularly high ease of use. Due to the arrangement of the handle-side connection point and/or the tamping-pickside connection point of the first vibration decoupler above the machine center of gravity, the connection point is ularly far away from the tamping pick, in particular from the decisive ion source of the hand tamping device. In addition, this connection point is arranged opposite the tamping pick with respect to the center of mass, whereby vibrations at the at least one handle are reduced in a particularly comprehensive manner by the particularly strong inertial damping in the region of the e center of gravity. The damping effect is increased and the ion load acting on the user is reduced.

Preferably, a hand-held tamping machine configured such that a ce of the at least one handle from the motor center of gravity and a distance of the motor center of gravity from a handle-side connection point of the first vibration decoupler are in a ratio in the range of 1:1 to 4:1 s a ularly high ease of use. The motor center of gravity and the handleside connection point of the first vibration decoupler are ed along the shaft axis preferably n the at least one handle and the machine center of gravity. This reduces the vibrations transmitted to the motor and/or the handle device. The vibrations excited at the at least one handle are particularly low if the ratio between the distance of the at least one handle from the motor center of gravity and the distance of the motor center of gravity from the handle-side connection point of the first vibration decoupler is in a range from 1:1 to 4:1, in particular from 1.5:1 to 3.5:1, in particular from 2:1 to 3:1. With this ement, it is advantageously achieved that the mass of the motor exerts a particularly high inertial damping effect on the handle device.

In one preferred embodiment, a hand-held tamping machine configured such that along the shaft axis a distance between a tamping-pick-side connection point of the first vibration decoupler and the machine center of gravity is a maximum of 15 % of the overall height of the hand-held g machine has a particularly high ease of use. The tamping-pick-side connection point of the first vibration decoupler can be arranged above or below the machine center of gravity. The distance between the tampingpick-side connection point of the first vibration decoupler and the e center of gravity is preferably a maximum of 15 %, in particular a maximum of 10 %, especially a maximum of 5 %, of the overall height of the hand-held tamping e. In the region of the e center of gravity, the hand-held tamping machine experiences particularly high inertial g. A particularly strong reduction in the vibration transmitted to the handle device and/or the motor via the tamping-pick-side connection point of the first vibration decoupler can be achieved with such an arrangement.

Preferably, a hand-held tamping machine configured such that along the shaft axis a distance between a handle-side tion point of the first vibration decoupler and the machine center of y is a maximum of 20 % of the overall height of the hand-held tamping machine has a particularly high ease of use during operation. ably, the distance along the shaft axis between the handle-side connection point of the first vibration decoupler and the machine center of gravity is a m of 20 %, in ular a maximum of 15 %, in particular a maximum of 10 %, in ular a maximum of 5 % of the overall height of the hand-held tamping machine. The handle-side connection point of the first vibration decoupler is arranged along the shaft axis preferably between the at least one handle and the machine center of gravity and/or above the tampingpick-side connection point of the first vibration decoupler. The inertial damping due to the mass of the hand-held tamping machine thus has a particularly strong effect on reducing the vibrations at the at least one handle.

In one preferred embodiment, a hand-held tamping machine configured such that the first ion decoupler and/or a second vibration decoupler are arranged completely above the e center of gravity is particularly convenient to operate. Due to the fact that the first and/or the second vibration decoupler are ed opposite the tamping pick and/or the vibration generator with respect to the machine center of gravity, the vibrations transmitted o are reduced, in particular due to the particularly strong inertial damping in the region of the machine center of gravity. Correspondingly, the vibrations transmitted to the motor and/or the at least one handle are reduced.

Preferably, a hand-held tamping e including a second vibration decoupler which acts between the handle device and the tamping pick and/or the motor ensures even lower vibrations at the at least one handle.

The hand-held tamping machine may have the first vibration decoupler and/or the second vibration decoupler. The second vibration ler may be arranged above or below the first vibration decoupler or overlap the first vibration decoupler along the shaft axis. The second vibration decoupler may be substantially configured to correspond to the first vibration decoupler. Preferably, the second vibration decoupler is ted with the second vibration decoupler via a rigid head support ure, in particular a supporting plate. Preferably, the second ion decoupler acts n the handle device and/or the motor and the tamping pick and/or the vibration generator and/or between the handle device and the motor. The second vibration decoupler can release a limited ve movement between the at least one handle and the tamping pick and/or the vibration generator and/or the motor and/or between the motor and the tamping pick and/or the vibration generator, in particular in any horizontal direction and/or in the vertical direction. The second vibration decoupler may have at least one decoupling element, in particular a spring element and/or a damping element, in particular a rubber-elastic t. Preferably, the first and/or the second vibration ler have a plurality of the ling elements.

In one preferred embodiment, a hand-held tamping machine configured such that the motor is a combustion engine or an electric motor is particularly flexible in use. Preferably, the hand-held tamping machine comprises an energy source, in particular a fuel tank for supplying the combustion engine with fuel or an accumulator for supplying the electric motor with electric power.

Preferably, a hand-held tamping machine configured such that the vibration generator is ed at least in sections in a tamping pick tube enables compacting of the track ballast in a particularly time- and energy-efficient manner. The vibration generator can have an imbalance mass arranged eccentrically to the shaft axis, in particular ed completely inside the tamping pick, in particular inside a tamping pick tube. This allows the vibration excitation to take place particularly close to the track ballast, which means that the kinetic energy applied can be dissipated to the track ballast y without loss. The vibration excitation of the at least one handle and the motor, on the other hand, is d.

Further features, details and advantages of the invention will be apparent from the following description of an exemplary ment based on the figures.

Brief ption of the Figures Fig. 1 shows a front view of a hand-held tamping machine for compacting track ballast, having a tamping pick for penetrating the track ballast, a vibration generator, a motor for driving the vibration generator in rotation, and a handle device for steering the hand-held tamping machine in operation, and Fig. 2 shows a sectional view of the hand-held tamping machine in Fig. 1 through an axis of rotation of a drive shaft, which connects the motor to the vibration tor in a torque- transmitting manner.

Detailed Description With nce to Fig. 1 and Fig. 2, a hand-held tamping machine 1 for compacting track ballast 2 is described. Track rails 3 are attached to track sleepers 4, which rest on the track t 2. In Fig. 1, the hand-held tamping machine 1 is shown in operation, n the hand-held tamping machine 1 penetrates the track ballast 2 in a vertical orientation to a depth below the track sleepers 4 for compacting the track ballast 2.

The hand-held tamping machine 1 has a tamping pick 5, a vibration generator 6, a motor 7 and a handle device 8. The tamping pick 5 comprises a tamping pick tube 9 and a ballast contact attachment 10 which surrounds the tamping pick tube 9 at least in ns. The ballast contact attachment 10, which is subject to wear, is replaceably attached to the tamping pick tube 9.

The vibration generator 6 is configured to excite the g pick 5 to vibrate. The motor 7 and the vibration generator 6 are configured to induce a vibration frequency in a range from 20 Hz to 100 Hz, in particular from 30 Hz to 60 Hz. The ion generator 6 has an eccentric shaft 11 which is rotatably mounted in the g pick tube 9 about an eccentric axis 12 by means of two tubular gs 13a, 13b. An imbalance mass 14 is attached to the eccentric shaft 11. In a direction perpendicular to the eccentric axis 12, the imbalance mass 14 is completely overlapped by the tamping pick tube 9 and the ballast contact attachment 10.

The engine 7 is an internal combustion engine, in particular a gasoline motor. Alternatively, the motor 7 may also be configured as an electric motor. In order to drive the vibration generator 6 in rotation, the motor 7 is ted to it via a drive shaft 15. The drive shaft 15 is rotatably mounted about a shaft axis 16. The drive shaft 15 is connected with the eccentric shaft 11 in a reversibly detachable and torque-transmitting manner. The drive shaft 15 can alternatively be non-detachably connected with the eccentric shaft 11, in particular be configured as one piece with it. The eccentric shaft 11 and the drive shaft 15 are configured coaxially.

The handle device 8 has two handles 17a, 17b. The handles 17a, 17b comprise a plastic material, in particular they are ured as rubber handles. The motor 7 has a power adjustment element 18, in particular a throttle lever, for regulating the power output. The power adjustment element 18 is arranged at the first handle 17a such that the user does not have to take his hand off the handle 17a to adjust the motor power.

The s 17a, 17b are connected with the motor 7 and the tamping pick 5 via a support structure 19. The support structure 19 is a tubular structure which is essentially made of metal.

The hand-held tamping machine 1 has a first vibration decoupler 20 and a second vibration decoupler 21. The first vibration decoupler 20 acts between the tamping pick 5 and the handle device 8 and the motor 7. For this purpose, the first vibration ler 20 is ted to the g pick 5 via a tamping-pick-side connection point 22. A handle-side connection point 23 of the first vibration decoupler 20 is connected with the handle device 8 and the motor 7. In ular, the first vibration decoupler 20 is attached to a pick support structure 24 via the gpick-side connection point 22. The first vibration decoupler 20 is attached to a head support structure 25 via the handle-side connection point 23. The head t structure 25 is configured as a supporting plate. The motor 7 is attached, in particular rigidly, to the head support structure 25.

The second vibration decoupler 21 acts between the handle device 8 and the tamping pick 5 as well as the motor 7, in particular the head support structure 25. For this purpose, the second vibration decoupler 21 is ted with the tamping pick 5 via a tamping-pick-side connection point 26, in particular attached to the head support structure 25. The second vibration decoupler 21 is connected with the handle device 8, in particular attached to the support structure 10, via a handle-side connection point 27.

The first vibration decoupler 20 and the second ion decoupler 21 each comprise four decoupling ts 28a, 28b made of a rubber-elastic material. The decoupling elements 28a, 28b of the respective vibration decoupler 20, 21 are connected in parallel with each other. The second vibration decoupler 21 is connected in series with the first vibration decoupler 20.

The two vibration decouplers 20, 21 each allow limited relative nt of the tamping-pick-side connection points 22, 26 with respect to the handle-side connection points 23, 27 in all l directions.

For power transmission between the motor 5 and the vibration generator 6 while tolerating corresponding relative movements, the drive shaft 15 is ured in two portions. A third vibration decoupler 31 acts between a first drive shaft portion 29 and a second drive shaft n 30. The first drive shaft n 29 is connected to the second drive shaft portion 30 via the third vibration decoupler 31 in a torque-transmitting manner. The third vibration decoupler 31 allows a d displacement of the first drive shaft portion 29 relative to the second drive shaft portion 30 along the shaft axis 16, and a limited relative swiveling movement about any axis perpendicular to the shaft axis 16.

The hand-held tamping machine 1 has an overall height H of 1060 mm, which corresponds to the overall dimension of the hand-held tamping e 1 along the shaft axis 16. A machine center of gravity SP0 is located along the shaft axis 16 in the center of the eld tamping machine 1. The machine center of gravity SP0 is arranged at a distance hG0 of 530 mm from the handles 17a, 17b.

Distances with respect to the at least one handle 17a, 17b are measured towards the upper side of the handle 17a, 17b. In general, when determining the masses and dimensions of the hand-held g e 1, it is assumed that the hand-held tamping machine 1 is in an operational state, in which in particular the ballast contact attachment 10 is attached to the tamping pick tube 9 and/or a fuel tank 32 of the motor 7 is, for example, half filled with fuel.

A motor center of gravity SPM is arranged below the handles 17a, 17b at a distance hGM of 240 mm from the handles 17a, 17b. Accordingly, a distance h0M between the machine center of gravity SP0 and the motor center of gravity SPM is 290 mm.

The handle-side tion point 23 of the first vibration decoupler 20 is arranged at a distance hT0 of 120 mm from the machine center of gravity SP0. Consequently, a ce hMT between the motor center of gravity SPM and the -side connection point 23 is 170 mm, and the ce hGM between the motor center of gravity SPM and the handles 17a, 17b is 240 mm. A distance ht0 between the machine center of gravity SP0 and the tamping-pick-side connection point 22 of the first vibration decoupler 20 is 60 mm.

A distance h0F between the machine center of gravity SP0 and a force application point KP of the resulting eccentric force F provided by the ion generator 6 is 383 mm.

The mode of operation of the hand-held tamping machine 1 is as follows: The hand-held tamping machine 1 is in an operable state, with the fuel tank 32 half-filled and the t t attachment 10 attached to the tamping pick tube 9. The user grips the hand-held tamping machine 1 by the handles 17a, 17b to carry it to the on of the track ballast 2 to be compacted. The motor 7 is started and drives the vibration generator 6 according to the power set by the power adjustment element 18. The vibration generator 6 causes the tamping pick 5 to vibrate. Steered by the user via the s 17a, 17b and under the action of the weight of the hand-held tamping machine 1, the tamping pick 5 penetrates the track ballast 2.

The tamping pick 5 transmits the vibrational motion to the track t 2, which is compacted as a result. To support the g of the track sleeper 4, the user can swivel the hand-held tamping machine 1 about a horizontal axis oriented in particular parallel to the respective track sleeper 4. As a result, compaction of the track ballast 2 below the track sleeper 4 can be achieved particularly efficiently and reliably.

The vibrations d at the handles 17a, 17b result at least in part from a rigid-body motion of the hand-held tamping machine 1. In Fig. 1, the shaft axis 16 is rated in the vertical orientation of the hand-held tamping e 1. The shaft axis 16' drawn in obliquely to the vertical direction symbolizes the rigid-body motion of the track tamping machine 1 resulting from the eccentric force F. Here, the resulting vibration amplitude is shown greatly exaggerated. The d rigidity of the hand-held tamping machine 1, in particular of the ion decouplers 20, 21, is not taken into account in the rigid-body vibration. In a vibration nodal point SKP, the position of which depends on the mass distribution of the eld tamping e 1, a minimum of the vibration amplitude prevails, in particular it is zero.

Along the shaft axis 16, a distance hGP n the handles 17a, 17b and the vibration nodal point SKP is 60 mm. Due to the proximity of the handles 17a, 17b to the vibration nodal point SKP, the respective vibration amplitude prevailing at the handles 17a, 17b is particularly low.

The vibration decouplers 20, 21, 31 reduce the vibrations transmitted from the tamping pick 5 and/or the vibration generator 6 to the handle device 8, in particular the handles 17a, 17b, and the motor 7. As a result, the service life of the motor 7 can be extended due to reduced stresses. Furthermore, a considerable relief of the user results.

The large distance hGM between the handles 17a, 17b and the motor center of gravity SPM, particularly in relation to the height H, has a particularly advantageous effect on the ease of use. The source of noise and/or exhaust emissions formed by the motor 7 is thus particularly far away from the user's head. In on, the motor 7 is arranged particularly close to the machine center of gravity SP0, as a result of which the motor 7 is subjected to particularly low vibration loads due to increased inertial damping ling there.

It has been found that the reaction forces acting on the user via the handles 17a, 17b are ent on the aforementioned distances, in particular the arrangement of the machine center of gravity SP0, the motor center of gravity SPM, the force application point KP and the handles 17a, 17b along the shaft axis 16. The prevailing ion of the distances results in particular in the arrangement of the handles 17a, 17b close to the vibration nodal point SKP. In the ling hand-held tamping machine 1, the reaction forces acting on the user or the vibration excitation at the handles 17a, 17b are particularly low. The hand-held tamping machine 1 is thus particularly user-friendly in operation.

Patent

Claims (15)

Claims

1. A hand-held tamping machine for ting track ballast, having - a g pick for penetrating the track ballast, 5 - a vibration generator for vibration excitation of the tamping pick, - a motor which is connected with the vibration generator via a drive shaft, - a handle device having at least one handle for steering the handheld tamping machine during operation, 10 n along a shaft axis of the drive shaft, the at least one handle - is arranged above a machine center of gravity of the hand-held tamping machine by at least 30 % of an l height of the handheld tamping e and/or - is arranged above a motor center of gravity of the motor by at least 15 15 % of the overall height of the hand-held tamping machine.

2. The hand-held tamping machine ing to claim 1, wherein along the shaft axis the at least one handle is arranged above the machine center of gravity by at least 40 % of the overall height of the hand-held 20 tamping machine.

3. The hand-held tamping machine according to claim 1 or 2, wherein along the shaft axis the machine center of gravity is arranged at a maximum of 60 % of the overall height of the hand-held tamping 25 machine below the at least one handle.

4. The hand-held tamping e according to any one of the preceding claims, wherein along the shaft axis the at least one handle is arranged above the motor center of gravity by at least 20 % of the overall height 30 of the hand-held tamping machine.

5. The eld tamping machine according to any one of the preceding claims, wherein along the shaft axis a distance between the at least one handle and a vibration nodal point of the hand-held g machine 5 due to the vibration excitation by the vibration generator is a m of 15 % of the overall height of the hand-held tamping machine.

6. The hand-held tamping machine according to claim 5, wherein the vibration nodal point is caused by a rigid-body motion and/or an elastic 10 deformation of the hand-held tamping machine.

7. The hand-held tamping machine according to any one of the preceding claims, including a first vibration decoupler which acts between the tamping pick and the handle device and/or the motor.

8. The hand-held tamping machine according to claim 7, wherein a handle-side connection point and/or a tamping-pick-side connection point of the first vibration decoupler are arranged above the machine center of gravity.

9. The hand-held g machine according to claim 7 or 8, n a distance of the at least one handle from the motor center of gravity and a distance of the motor center of gravity from a handle-side connection point of the first vibration decoupler are in a ratio in the range of 1:1 to 25 4:1.

10. The hand-held tamping e ing to any one of claims 7 to 9, wherein along the shaft axis a distance between a tamping-pick-side connection point of the first vibration decoupler and the machine center of gravity is a maximum of 15 % of the overall height of the hand-held g machine.

11. The hand-held tamping machine according to any one of claims 7 to 5 10, wherein along the shaft axis a ce between a handle-side tion point of the first vibration decoupler and the e center of gravity is a maximum of 20 % of the overall height of the hand-held tamping machine. 10

12. The hand-held tamping machine according to any one of claims 7 to 11, wherein the first vibration decoupler and/or a second vibration decoupler are ed completely above the machine center of gravity. 15

13. The hand-held tamping machine according to any one of the preceding claims, including a second vibration decoupler which acts between the handle device and the tamping pick and/or the motor.

14. The eld tamping machine according to any one of the preceding 20 claims, wherein the motor is a combustion engine or an electric motor.

15. The hand-held tamping machine according to any one of the preceding claims, wherein the vibration generator is arranged at least in sections in a tamping pick tube. 17b 1 7 SKP 32 18 17a 19 hGM 21 h0M 22 hT0 31 H 16 h0F KP F