Control apparatus for soil compacting apparatus

Abstract

A control apparatus for a soil compacting apparatus such as a vibratory plate has a movable operating element for specifying a running direction of the soil compacting apparatus by way of an operator, and having a hydraulic master device, with a master cylinder, in which a master piston can be moved to and fro in a linear manner, in order to generate a hydraulic signal. A hydraulic connector serves for coupling hydraulic components of the soil compacting apparatus and for transmitting the hydraulic signal from the master device. A transmission device is provided for converting the movement of the operating element into a linear movement of the master piston, it being possible for the operating element to be moved between a first position (V) and a second position (R). The first position corresponds to a maximum forward movement of the soil compacting apparatus, and the second position corresponds to a maximum reverse movement of the soil compacting apparatus. A latching device is provided for releasably holding the operating element in a predefined position, for example the first position.

Claims

1. A control apparatus for a soil compacting apparatus, comprising: an operator-controlled movable operating element for specifying a running direction of the soil compacting apparatus; a hydraulic master device having a master cylinder in which a master piston can be moved to and fro in a linear manner in order to generate a hydraulic signal; a hydraulic connector for coupling hydraulic components of the soil compacting apparatus to one another and for transmitting the hydraulic signal from the master device; and a transmission device for converting the movement of the operating element into a linear movement of the master piston, wherein the operating element is movable between a first position (V) and a second position (R), the first position corresponding to a maximum forward movement of the soil compacting apparatus, and the second position corresponding to a maximum reverse movement of the soil compacting apparatus, and wherein a latching device is provided for releasably holding the operating element in a predefined position, wherein the latching device has a pressure piece with a latching element which is mounted in a sprung manner, and wherein the latching device has a recess into which the latching element can be introduced, and wherein the recess is configured on the transmission device or on the master piston.

2. The control apparatus as claimed in claim 1, wherein, the predefined position corresponds to the first position.

3. The control apparatus as claimed in claim 1, wherein the operating element is held releasably by way of the latching device in such a way that the operating element can be moved out of the predefined position by the operator with the aid of his/her manual force by way a latching force of the latching device being overcome.

4. The control apparatus as claimed in claim 1, wherein the latching device is switchable between two operating states, namely a first operating state in which the releasable holding of the operating element in the predefined position is brought about by way of the latching device, and a second operating state in which the latching device is without action.

5. The control apparatus as claimed in claim 1, wherein the operating element is pivotable about an axle; and the transmission device is configured for converting the pivoting movement of the operating element into a linear movement of the master piston.

6. The control apparatus as claimed in claim 1, further comprising a control housing in which the operating element is moveably held and in which the master cylinder and the master piston are arranged.

7. The control apparatus as claimed in claim 1, wherein, the transmission device has a pinion shaft which is coupled to the operating element, and a rack which is coupled to the master piston; and wherein the pinion shaft meshes with the rack in such a way that a rotation of the pinion shaft brings about a linear displacement of the rack.

8. The control apparatus as claimed in claim 1, wherein, the pressure piece is mounted in the control housing; the recess is configured on the master piston or in the pinion shaft; and wherein the latching element is introduced into the recess when the operating element is in the predefined position.

9. The control apparatus as claimed in claim 1, wherein the master piston has a piston rod in which the rack is configured; the recess is configured in the piston rod; and wherein a further, longitudinally extending recess is configured as a clearance portion in the longitudinal direction of the piston rod offset with respect to the recess.

10. The control apparatus as claimed in claim 1, wherein the pressure piece is mounted in the control housing such that it can be moved between two positions; the first position of the pressure piece being defined in such a way that the latching element of the pressure piece can be introduced into the recess, and the second position of the pressure piece being defined in such a way that the latching element cannot be introduced into the recess; and further comprising a switchover device for moving and holding the pressure piece in a defined manner into/in the first position or into/in the second position.

11. The control apparatus as claimed in claim 1, wherein the switchover device has a pivotable lever with an eccentric geometry; and wherein the lever is pivotable into two defined positions in accordance with the two positions of the pressure piece.

12. The control apparatus as claimed in claim 1, wherein the operating element is pivotable into a third position which is provided between the first position and the second position and which corresponds to a standstill of the soil compacting apparatus.

13. The control apparatus as claimed in claim 1, wherein, the soil compacting apparatus is a vibratory plate.

14. A vibratory plate comprising: a soil contact plate, an unbalance exciter mounted on the soil contact plate; a longitudinally extending drawbar provided on the vibratory plate and having a free end, a control apparatus provided on the free end of the drawbar, the control apparatus including an operator-controlled movable operating element for specifying a running direction of the vibratory plate; a hydraulic master device having a master cylinder in which a master piston can be moved to and fro in a linear manner in order to generate a hydraulic signal; a hydraulic connector for coupling hydraulic components of the vibratory plate to one another and for transmitting the hydraulic signal from the master device; and a transmission device for converting the movement of the operating element into a linear movement of the master piston, wherein the operating element is movable between a first position (V) and a second position (R), the first position corresponding to a maximum forward movement of the vibratory plate, and the second position corresponding to a maximum reverse movement of the vibratory plate, and wherein a latching device is provided for releasably holding the operating element in a predefined position, wherein the latching device has a pressure piece with a latching element which is mounted in a sprung manner, and wherein the latching device has a recess into which the latching element can be introduced, and wherein the recess is configured on the transmission device or on the master piston.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) These and further advantages and features of the invention will be described in greater detail in the following text on the basis of examples with the aid of the accompanying figures, in which:

(2) FIG. 1 shows a control apparatus in accordance with the prior art in a sectional illustration and is labeled “PRIOR ART”,

(3) FIG. 2 shows the control apparatus from FIG. 1 in a perspective view and is labeled “PRIOR ART”,

(4) FIG. 3 shows a control apparatus according to the invention with an activated latching device,

(5) FIG. 4 shows the control apparatus from FIG. 3 with a deactivated latching apparatus, and

(6) FIG. 5 schematically shows a vibratory plate machine provided with the control apparatus of FIG. 3.

DETAILED DESCRIPTION

(7) FIGS. 3 and 4 show a control apparatus 50 which is largely of analogous construction with respect to the control apparatus which is known from the prior art and is described above on the basis of FIGS. 1 and 2. In order to avoid repetitions, identical components are therefore also labeled by way of identical designations. In addition, reference is made to the above description with regard to the general method of operation of the control apparatus.

(8) The control apparatus 50 thus has the switchover handle 2 which can be pivoted relative to the control housing 1. In the case of pivoting of the switchover handle 2, the pinion 8 is rotated about the axle 3, as a result of which the rack 7 which meshes with the pinion 8 is displaced in a linear manner. The rack 7 is configured in one piece together with the piston rod 6 and the master piston 4, with the result that a common displacement of the master piston 4 is brought about. Accordingly, a hydraulic signal can be transmitted via the hydraulic connector 10 to the soil compacting apparatus (not shown), in particular to the unbalance exciter in a vibratory plate.

(9) The switchover handle 2 does not necessarily have to be designed as a hoop-shaped operating element, but rather can also have another suitable design which allows an operation of the machine.

(10) A latching device 20 is provided in addition to the control apparatus 50 which is known in this regard from the prior art. The latching device 20 has a pressure piece 21, in the interior of which a latching pin 22 which serves as a latching element can be displaced counter to the action of a spring 23. The latching pin 22 exits at one end of the pressure piece 21 (the upper end in FIG. 3). Here, the front-side end of the latching pin 22 is of hemispherical or tip-shaped configuration and penetrates into a recess 24 in the piston rod 6. The recess 24 therefore serves as a latching notch, into which the latching pin 22 of the pressure piece 21 can engage.

(11) In the case of a movement of the piston rod 6 in the axial direction, the recess 24 is displaced relative to the tip-shaped end of the latching pin 22, with the result that the latter is pressed into the interior of the pressure piece 21 counter to the action of the spring 23.

(12) FIG. 3 shows a state, in which the switchover handle 2 and therefore the master piston 4 are in a position for maximum forward movement. In this state, the latching pin 22 is at the level of the recess 24, with the result that the tip of the latching pin 22 can penetrate into the recess 24.

(13) Depending on the positioning of the latching pin 22 and the recess 24, it is also possible to latch the switchover handle 2 in another position than in the position shown in FIG. 3 for maximum forward movement. For example, the latching device 20 can be positioned with the recess 24 in such a way that a latching action of the switchover handle 2 takes place in a position which corresponds to a reduced, that is to say retarded, forward movement. In this way, consideration can be given to safety concerns, in order that the vibratory plate cannot move with a maximum forward movement without control by way of the operator, but rather precisely only with a reduced forward movement.

(14) The latching pin 22 of the pressure piece 21 is spring-prestressed, the spring force being sufficiently great to hold the master piston 4 at the front, that is to say in the full forward movement shown in FIG. 3, which master piston 4 experiences a system-related restoring force. Here, the switchover handle can then be released by the operator and nevertheless does not move automatically into the neutral position for the vibration at a standstill.

(15) In the case of switched-on self-holding forward movement (activation of the latching device), the latching pin 22 bears merely against the lefthand flank of the recess 24 and is already pressed slightly into the pressure piece 21 in the process, that is to say the upper side of the collar of the latching pin 22 is free. This ensures that the master piston 4 is always pressed fully and without play toward the front (in the direction F).

(16) In another state (not shown), in which the switchover handle 2 is pivoted, for example into a position for maximum reverse movement, the position of the master piston 4 also changes together with the piston rod 6 and the rack 7. Accordingly, the recess 24 is displaced relative to the tip of the latching pin 22, with the result that the latching pin 22 is not seated in the recess 24. As a result, the master piston 4 can be moved freely in the linear direction. No latching action of the master piston 4 or the switchover handle 2 takes place.

(17) In order to increase the free mobility further in this state, a clearance portion 25 is configured in the piston rod 6 in addition to the recess 24. Here, the tip of the latching pin 22 can penetrate, without achieving a latching action. The clearance portion 25 can also be configured so as to be so deep that the latching pin 22 does not make contact with the piston rod 6 and no frictional effect between the two components is generated either.

(18) The complete pressure piece 21 including the latching pin 22 is mounted in the control housing 1 such that it can be moved in the axial direction. As a comparison of FIGS. 3 and 4 shows, the pressure piece 21 can therefore be moved between two positions and can be locked in the respective positions. In a first position (FIG. 3), it is possible that the tip of the latching pin 22 can penetrate into the recess 24 of the piston rod 6, as described above.

(19) In contrast to this, in the case of the second position which is shown in FIG. 4, the pressure piece 21 is disengaged somewhat downward in the axial direction or is spaced apart somewhat from the piston rod 6. As a result, the length of the latching pin 22 is no longer sufficient, in order to penetrate into the recess 24. In this state, the latching device 20 with the pressure piece 21 and the latching pin 22 is therefore without action and is thus deactivated.

(20) A switchover lever 26 is provided for switching over between the two positions of the pressure piece 21 and therefore for activating and deactivating the latching device 20, which switchover lever 26 has an eccentric outer face 27 and can be pivoted about a rotational axis 28, as is also shown in FIGS. 3 and 4.

(21) In the position which is shown in FIG. 3, the spacing between the eccentric outer face 27 which makes contact with the pressure piece 21 and the rotational axis 28 of the switchover lever 26 is greater than in the case of the position which is shown in FIG. 4. Accordingly, in the case of the position which is shown in FIG. 3, the pressure piece 21 is pressed in the direction of the recess 24.

(22) During normal working operation of the soil compacting apparatus, the operator will as a rule set the maximum forward movement, in order to achieve a rapid work result. To this end, the described latching action of the switchover handle 2 can be helpful because it makes it possible for the operator to release the switchover handle 2 and nevertheless retain the maximum forward movement.

(23) If the operator wishes to stop the machine or move it in a reverse movement, the latching or holding mechanism can be overridden. To this end, the operator pulls the switchover handle 2 back as usual, but with a somewhat elevated force effort. Here, the latching pin 22 is pressed into the pressure piece 21 counter to the spring force, until the restriction of the recess 24 is overcome completely. Subsequently, the latching pin 22 can disengage again. The disengaged latching pin 22 then lies with its collar within the pressure piece 21, and moves in the clearance portion 25, that is to say in a contact-free manner with respect to the piston rod 6. Therefore, no additional friction is generated between the piston rod 6 and the latching pin 22, which allows the vibratory plate to move automatically from reverse movement or possibly from slight forward movement into vibration at a standstill even in the case of a switched-on self-holding forward movement (activated latching device).

(24) If the operator then wishes to move into the maximum forward movement again, he/she presses the switchover handle forward again, as a result of which the latching pin 21 again moves over the boundary of the recess 24 (latching notch). Here, the spring prestress is perceived as a latching action via a change in the operating force on the switchover handle 2.

(25) If a latching action of this type is not desired by the operator, he/she can deactivate the latching device 20 by way of the switchover lever 26 being moved back, and he/she can therefore switch off the self-holding forward movement. If the piston rod 6 is then moved, the flank of the recess 24 pushes the complete pressure piece 21 away from the piston rod 6 without resistance. This operation is not perceived by the operator.

(26) In the case of one variant, the pressure piece 21 can also be provided with an external thread and can be screwed by means of a tool into the control housing 1 or the drawbar head. In this case, a switch-on capability without tools is possible.

(27) In the case of another variant, the pressure piece 21 can be provided with a coarse thread and can be screwed in or out manually via a rotary lever as far as respective end stops, whereby there is a switch-on capability without tools. The thread can be selected in such a way that even half a revolution is sufficient for switching on or off (activation and deactivation of the latching device).

(28) The latching pin 22 which serves as a latching element can also be replaced by a spring-prestressed ball. In this case, the pressure piece 21 can also be realized as a standard ball pressure piece.

(29) The pressure piece 21 and therefore the entire latching device 20 do not have to be arranged from below, as shown in FIG. 3. An arrangement from above or from the side is likewise possible.

(30) Referring to FIG. 5, a vibratory plate 100 is schematically illustrated as being provided with the control apparatus 50 of FIG. 3. The vibratory plate 100 includes a soil contact plate 102, on which an unbalance exciter 104 is mounted which, for example, has two eccentric shafts which can be rotated in opposite directions and can be set in opposed rotation by a drive. A longitudinally extending drawbar 106 is provided on the soil contact 102. The control apparatus 50, including the switchover handle 2 (FIGS. 3 and 4), is provided at a free end or drawbar head of the drawbar 106.