Wearable Drive System for a Work Apparatus

Abstract

A drive system includes a carrying device with a wearable carrying frame, an energy store carried by the carrying frame, and at least one electric drive motor carried by the carrying frame. A coupling device is configured to mechanically couple a work apparatus to the drive system. The carrying device is formed as a shoulder bag or backpack, having at least one strap that permits the carrying device to be worn over a shoulder of a user. Two straps may be provided that permit the carrying device to be worn over both shoulders of a user. Also disclosed is a tool having such a drive system and a work apparatus, which may be concrete vibrator.

Claims

1. A drive system comprising: a carrying device with a wearable carrying frame; an energy store carried by the carrying frame; at least one electric drive motor carried by the carrying frame; and a coupling device that is configured to mechanically couple a work apparatus to be driven by the drive motor to the drive system.

2. The drive system as claimed in claim 1, wherein the carrying device comprises a shoulder bag or backpack having at least one strap configured to permit the carrying device to be worn over a shoulder of a user.

3. The drive system as claimed in claim 2, wherein two straps are provided that are configured to permit the carrying device to be worn over both shoulders of a user.

4. The drive system as claimed in claim 1, wherein the coupling device is designed for the coupling of a drive shaft for the work apparatus to the drive system.

5. The drive system as claimed in claim 1, further comprising a transformer device which is carried by the carrying frame and which transforms an electrical current, which is drawn from the energy store, to a current suitable for powering the drive motor.

6. The drive system as claimed in claim 1, further comprising a hip strap which is connected to the carrying frame.

7. The drive system as claimed in claim 1, further comprising an electrical connection device which is carried by the carrying frame and which serves for the connection of a consumer device to the drive system.

8. The drive system as claimed in claim 1, further comprising a switching device which is carried by the carrying frame and which serves for the switching of an electrical connection between the energy store and the drive motor and/or for the switching of an electrical connection between the energy store and a transformer device which transforms an electrical current, which is drawn from the energy store, to a current suitable for powering the drive motor.

9. The drive system as claimed in claim 1, wherein the drive motor is located above the energy store.

10. A powered tool comprising: a work apparatus having a drive shaft; a carrying device with a wearable carrying frame; first and second shoulder straps extending forwardly of the carrying frame and configured to be worn over shoulders of a user; a hip strap extending forwardly of the carrying frame at a location beneath the shoulder straps and configured to be worn around the hip of the user; an energy store supported on the carrying frame and extending rearwardly of the carrying frame; at least one electric drive motor carried by the carrying frame and extending rearwardly of the carrying frame, the electric drive motor being located above the energy store; and a coupling device that mechanically couples the drive shaft of the work apparatus to the drive motor.

11. The powered tool of claim 10, wherein the work apparatus is an internal concrete vibrator and the drive shaft is a flexible drive shaft.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0044] These and further features and advantages will be discussed in more detail below on the basis of examples with the aid of the accompanying figures, in which:

[0045] FIG. 1 shows, in a schematic side view, a drive system which is formed as a backpack and which has an energy store and a drive motor;

[0046] FIGS. 2 to 6 show different variants of the drive system of FIG. 1;

[0047] FIGS. 7A and 7B show two rear views of the drive system of FIG. 6;

[0048] FIG. 8 shows the drive system for driving an internal vibrator for the compaction of concrete;

[0049] FIG. 9 shows another operating position in relation to the variant of FIG. 8;

[0050] FIG. 10 is a plan view of the drive system;

[0051] FIG. 11 shows a further operating position in relation to the variant of FIG. 8;

[0052] FIG. 12 shows yet another variant in relation to FIG. 8; and

[0053] FIG. 13 shows, in a schematic illustration, a coupling device for the coupling of a work apparatus that is to be driven by the drive motor.

DETAILED DESCRIPTION

[0054] FIG. 1 shows, in a schematic side view, a drive system designed in the form of a backpack, having a carrying frame 1, which may be designed for example as a carrying plate or carrying frame.

[0055] On the rear side, facing away from the operator, of the carrying frame 1, there is fastened a storage battery 2 which serves as energy store. The storage battery 2 may be received in a storage battery receptacle, which is provided specifically for this purpose and which serves as a fastening device, and thus fastened to the carrying frame 1. The storage battery receptacle may for example have an insertion slot or storage battery housing into which the storage battery 2 is exchangeably inserted. The insertion movement may take place in particular from above, such that the storage battery 2 is reliably held at its bottom side. When the storage battery 2 has been depleted, it can be removed from the storage battery receptacle and replaced with a fresh storage battery 2. The carrying frame 1 additionally includes an electrical connection device 20. The electrical connection device 20 allows for connection to a work apparatus

[0056] An electric drive motor 3 is also carried by the carrying frame 1. The drive motor 3 is suitably fastened to the carrying frame. The fastening may also be detachable, in order to enable the drive motor 3 to be easily exchanged if necessary.

[0057] In the case of the drive motor 3, various motor types may be used, which have already been described in detail further above in the introductory part of the description, such that another repetition at this juncture is not necessary.

[0058] The drive motor 3 is arranged below the storage battery 2. Since the drive motor generally has a relatively high weight, an advantageous center of gravity of the drive system as a whole is thus achieved.

[0059] The drive motor 3 has, as is conventional, a motor shaft (not illustrated), which extends for example perpendicularly with respect to the plane of the drawing of FIG. 1. A coupling device (likewise not illustrated) is provided on the shaft end of the motor shaft, to which coupling device a work apparatus can be coupled. In particular, the work apparatus may have a flexible shaft, which can be coupled to the motor shaft of the drive motor. The coupling between the motor shaft and the flexible shaft is designed as a detachable connection. In particular, this may be a conventional detachable shaft connection, such as for example a bayonet fastener, a sleeve nut or a bolt which is displaceable transversely with respect to the motor shaft, etc. The flexible shaft is conventionally designed as a square shaft which is inserted into a corresponding receptacle on the coupling device or the motor shaft. Numerous variants are known in the prior art for the coupling between the flexible shaft and the motor shaft, such that a more detailed presentation is not necessary.

[0060] Fastened to the carrying frame 1 are two carrying straps 4, of which only one is visible in the side view of FIG. 1, because the two carrying straps 4 are arranged one behind the other in relation to the plane of the drawing. The two carrying straps 4 may be designed similarly to the carrying straps on a typical hiking backpack, and may for example have padding in order to enable them to be worn comfortably by the operator on their two shoulders. The carrying straps 4 are fastened by means of their respective ends to the top side and to the bottom side of the carrying frame 1.

[0061] A carrying handle 5 may be provided at the upper end of the carrying frame 1 in order to make it easier for the user to carry the carrying device by hand.

[0062] A waist or hip strap 6 is attached to the bottom side of the carrying frame 1. The hip strap 6 may also be designed similarly to that in the case of a hiking backpack, in order to provide the operator with similar comfort. In particular, the hip strap 6 is suitable for supporting a considerable part of the total weight on the hip of the operator. In this way, the back and shoulders of the operator are relieved of load.

[0063] The hip strap 6 is in two parts and has a left-hand and a right-hand strap half, wherein only the left-hand strap half is visible in FIG. 1. The two strap halves may be closed by means of a conventional strap fastener in front of the abdomen of the operator to form an encircling strap.

[0064] The hip strap 6 may also be formed as a simple hip support, that is to say not as an encircling strap (possibly with a strap fastener in order to close the two strap halves to form an encircling strap). Rather, it is also possible merely for two support surfaces to be provided by the hip strap 6, by means of which a certain support action on the hip of the operator is made possible.

[0065] FIG. 2 shows a variant of the arrangement of FIG. 1. Here, a frequency transformer 7 is arranged as a further component in addition to the components already mentioned.

[0066] The frequency transformer 7 is connected electrically between the storage battery 2 and the drive motor 3 and serves for converting the direct current drawn from the storage battery 2 into a suitable current for the drive motor 3. In particular, it is possible here for the direct current from the storage battery 2 to be transformed into an alternating current with suitable frequency and voltage.

[0067] As in the embodiment of FIG. 1, the drive motor 3 is installed in a lower region on the carrying frame 1, in order to realize an expedient center-of-gravity distribution on the carrying frame 1 for the wearer or user. Owing to the advantageous weight distribution on the carrying frame 1, the shoulders are relieved of load via the carrying straps 4, whilst the major part of the weight is accommodated by the hip or the pelvic bone of the user.

[0068] FIG. 3 is a variant in relation to FIG. 2. Here, the storage battery 2 and the frequency transformer 7 form a structural unit 8. The storage battery 2 and the frequency transformer 7 can possibly be removed jointly, in the form of the structural unit 8, from the carrying frame 1 and replaced with another structural unit.

[0069] FIG. 4 shows a further variant, in which, in turn, the drive motor 3 and the frequency transformer 7 form a structural unit 9.

[0070] Analogously, FIG. 5 shows a variant in which the storage battery 2 and the drive motor 3 form a structural unit 10.

[0071] FIG. 6 shows a variant in which the drive motor 3 is fastened to the carrying frame 1 by means of a corresponding motor holder 11.

[0072] Whereas, in the variants of FIGS. 1 to 5, the drive motor 3 is only fastened in a suitable manner to the carrying frame 1, the motor holder 11 makes it possible for the motor 3 to be able to be moved relative to the carrying frame 1.

[0073] It is thus possible for the drive motor 3 to be able to be pivoted, for example through 90° or through 180°, about a pivot axis X extending perpendicular to the carrying frame 1. It is thus possible for the motor shaft and thus the coupling point for the work apparatus to be able to be displaced in a suitable manner. For example, the coupling point can be selectively positioned to the left or to the right of the back of the operator. It is likewise possible—in the case of a 90° rotation—for the coupling point to be displaced downward, such that the flexible shaft is led away vertically downward.

[0074] In one variant, the motor holder 11 also makes it possible for the drive motor 3 to be able to be displaced—for example on a rail—relative to the carrying frame 1 in the direction of an arrow. This is depicted in particular by the illustrations in FIGS. 7A and 7B, which show the drive system in a rear view.

[0075] In FIG. 7A, the drive motor 3 is situated centrally with respect to the carrying plate 1.

[0076] By contrast, in FIG. 7B, the drive motor 3 has been displaced to the left in the direction of an arrow, and is thus situated above the left hip of the operator when the backpack-like drive system is worn by the operator.

[0077] As an alternative to the abovementioned position of the drive motor 3, said drive motor may also be arranged above the storage battery 2 or at the same height as the storage battery 2. In particular, the motor shaft of the drive motor 3 may be oriented vertically upward, such that a connected flexible shaft extends over a shoulder of a user. This facilitates the work of the user, because a part of the weight of the flexible shaft is supported by the flexural stiffness of the flexible shaft.

[0078] The drive motor 3 may also be arranged so as to be freely pivotable, in particular rotatable about a horizontal axis X (see FIG. 6) which is perpendicular to the carrying frame, such that the motor shaft can point to both sides of a user and also upward or downward.

[0079] FIG. 8 shows a usage example for the use of the drive system for driving an internal vibrator 12 for the compaction of concrete that is still in a flowable state.

[0080] The construction of such an internal vibrator 12, also referred to as flexible-shaft vibrator, is known per se. The internal vibrator 12 has a flexible drive shaft 13 which is led in a protective hose and which is connected at one end by means of a coupling device 14 to a motor shaft (not illustrated) of the drive motor 3 and at its other end to a so-called vibrator cylinder 15. The vibrator cylinder 15 is designed as a cylindrical hollow body, in the interior of which an imbalance shaft (not illustrated in the figure) is wobbly mounted. The imbalance shaft can be set in rotation with the drive motor 3 via the drive shaft 13, whereby vibrations are generated which can be transmitted via the vibrator cylinder 15 to the concrete that is to be compacted. The vibrator cylinder 15 is also referred to as vibrator casing or vibration body.

[0081] In the example shown in FIG. 8, the motor shaft is—in relation to a user wearing the carrying frame 1—directed vertically upward, such that the drive shaft 13 is also initially led vertically upward. Over its further course, the flexible drive shaft 13 curves forward over the shoulder of the user and can thus be easily controlled by the user for the purposes of concrete compaction.

[0082] FIG. 9 shows a variant in relation to FIG. 8, in which the motor shaft of the drive motor 3 is led horizontally forward (in relation to the user or the intended wearing position), such that the coupled drive shaft 13 likewise extends forward. It is expediently possible for the drive shaft 13 to be designed to be shorter in this case than in the example of FIG. 8.

[0083] FIG. 10 shows a plan view of the drive system, with the drive motor 3 held on the carrying frame 1 by the motor holder 11, and different position variants and movement directions of the drive motor 3 relative to the carrying frame 1.

[0084] FIG. 11 shows a further usage example in a plan view, in the case of which the drive shaft 13 is led laterally past the operator and past the carrying frame 1 on the left.

[0085] In the example of FIG. 12, the drive shaft 13 is led over the shoulder (not illustrated) of the operator. This usage situation is similar to that of FIG. 8.

[0086] FIG. 13 shows an example for the coupling device 14 for the connection of a motor shaft 16 of the drive motor 3 to the drive shaft 13.

[0087] The drive shaft 13 is guided rotatably in a protective hose 17. The protective hose 17 accordingly also serves as a guide or operator control hose. The end of the drive shaft 13 is formed as a square 18, into which the correspondingly suitably designed end of the motor shaft 16 is inserted in order to transmit the torque from the motor shaft 16 to the drive shaft 13. To secure the plug connection between the motor shaft 16 and the drive shaft 13, a bolt 19 is provided.

[0088] In all variants, a switching device (not shown in the figures) may be provided, which is designed to selectably switch the current supply between the storage battery 2 and the drive motor 3. For this purpose, the switching device can for example selectably produce and/or shut off a current flow between the at least one storage battery 2 and the frequency transformer 7. It is furthermore conceivable for the switching device to be able to produce and/or shut off the current supply between the frequency transformer 7 and the drive motor 3. The switching device may furthermore also be arranged within the storage battery 2, such that the terminals of the storage battery 2 can be switched into a deenergized state during an exchange, and there is thus no danger to a user.