Abstract
A tensioning device for a crossbow or the like, such as a harpoon, a line throwing device, a toy crossbow, a pistol crossbow, a spear thrower, or a ballista, includes a shaft and limbs connected thereto. A connection element designed to connect to the shaft of the crossbow has securing devices for rotatably or pivotally securing the limbs. The connection element is connected to at least one drive device which can be connected to the limbs and by which the limbs can be converted rotatably or pivotally from a first position, in which the limbs form a first angle together with the shaft, into a second position, in which the limbs form a second angle together with the shaft, wherein the second angle is larger than the first angle, in order to convert the limbs and a bowstring connected thereto from a non-tensioned position into a tensioned shoot-ready position.
Claims
1. A tensioning device for a device with a shaft and limbs connected thereto, wherein a connection element is provided which is designed for connection to the shaft of the device crossbow and which comprises securing devices for rotatably or pivotally connecting the limbs, wherein the connection element is connected to at least one drive device, which can be connected to the limbs and by means of which drive device the limbs can be rotatably or pivotally moved from a first position, in which the limbs form a first angle together with the shaft, into a second position, in which the limbs form a second angle together with the shaft, wherein the second angle is larger than the first angle in order to move the limbs and a bowstring connected thereto from a non-tensioned position into a shoot-ready tensioned position.
2. The tensioning device according to claim 1, wherein the securing devices are rotatably or pivotally connected to the connection element.
3. The tensioning device according to claim 2, wherein the at least one drive device is arranged on the rotatable or pivotal securing devices.
4. The tensioning device according to claim 1, wherein the drive device is an electrically driven, hydraulic driven, pneumatically driven drive device or a drive device driven by a combination of these.
5. The tensioning device according to claim 4, wherein for energy supply the drive device comprises an integrated or replaceable compressed-air container or store for electrical energy as a shoulder support.
6. The tensioning device according to claim 1, wherein the drive device comprises at least one lifting device with a hydraulically, electrically or pneumatically displaceable reciprocating piston.
7. The tensioning device according to claim 6, wherein the drive device respectively comprises a hydraulically, electrically or pneumatically driven lifting device which can be connected to a limb, the reciprocating piston of which lifting device forms an acute angle with an imagined extension of the shaft.
8. The tensioning device according to claim 1, wherein the drive device is designed to move the limbs, following firing a shot, from the second position in a direction of the first position.
9. The tensioning device according to claim 8, wherein the drive device is designed to be deactivatable and for deactivation comprises a deactivation device, which can be actuated by the limbs or the bowstring at the end of firing a shot, in order to rotate or pivot the tensioned limbs automatically in a direction of the first position.
10. The tensioning device according to claim 9, wherein the deactivation device comprises an actuating element for relieving pressure on the hydraulically, electrically or pneumatically driven lifting device.
11. The tensioning device according to claim 8, wherein the drive device comprises at least one return spring for an automatic return of the limbs in a direction of the first position.
12. The tensioning device according to claim 1, wherein the drive device is fitted with a sound absorber.
13. The tensioning device according to claim 1, wherein the drive device is connected to a safety element and this is connected to a safety device, which safety device is designed both to mechanically fix or to release the bowstring in/from a triggering device connected to the shaft as well as to activate or deactivate the drive device, wherein the safety device, in a deactivation position of the safety element, deactivates the drive device, in a safety position of the safety element activates the drive device and fixes the bowstring, and in a release position of the safety element, activates the drive device and releases the bowstring for firing a shot.
14. A crossbow with a shaft extending in a shooting direction for receiving a projectile, and with two limbs rotatably or pivotally connected to the shaft, to which limbs a bowstring provided for engaging in the projectile is attached, wherein the tensioning device according to claim 1 is arranged on the shaft.
15. The crossbow according to claim 14, wherein a magazine for projectiles is arranged on the shaft.
Description
(1) The invention will now be described in further detail by way of preferred, non-restricting embodiments with reference to the drawings, in which
(2) FIG. 1 shows a tensioned crossbow with a tensioning device according to the invention;
(3) FIG. 2 shows a detail view of the tensioning device of the crossbow as per FIG. 1;
(4) FIG. 2A shows the detail view from FIG. 2, merely for the purpose of gaining understanding, with a tensioned and a relaxed limb;
(5) FIG. 3 shows the crossbow as per FIG. 1 directly after firing a shot;
(6) FIG. 4 shows the crossbow as per FIG. 1 after firing a shot with already relaxed limbs;
(7) FIG. 5 shows the crossbow as per FIG. 1 after firing a shot with relaxed limbs and a bowstring connected to a triggering device;
(8) FIG. 6 shows the crossbow as per FIG. 1 in a tensioned state prior to firing a shot;
(9) FIG. 7 shows a perspective view of a crossbow according to the invention;
(10) FIGS. 8A to 8C show a safety element for a drive device for a crossbow in three different positions; and
(11) FIG. 9 shows a schematic view of a tensioning device for a crossbow according to the invention.
(12) FIG. 1 shows a crossbow 2 in a tensioned state, with a shaft 3 and limbs 4 connected thereto, and with a tensioning device 1 according to the invention. The tensioning device 1 may be designed as a retrofit device for crossbows 2 or similar devices such as harpoons, line throwing devices, toy crossbows, pistol crossbows, spear throwers (ballistas) or be integrated in crossbows or similar devices. The tensioning device 1 comprises a connection element 5, which is designed for connecting, for example screwing it in a stable and possibly detachable manner to the shaft 3 of the crossbow 2. The connection element 5 has two securing devices 6 (attachment devices 6), that is one each per limb 4 arranged thereon, with which securing devices 6 the limbs 4 are rotatably or pivotally attached to the crossbow 2. In the exemplary embodiments shown the securing devices 6 are rotatably or pivotally connected to the connection element 5 by means of pins B1 about an axis of rotation A1 (see FIG. 2A). The limbs 4 are firmly connected, for example screwed or clamped, to the securing devices 6. Furthermore the connection element 5 is connected to two drive devices 7, which are for example by means of pins B2 also connected so as to be rotatable about an axis of rotation A2, to the rotatable or pivotal securing devices 6. The drive devices 7 rotate or pivot the limbs 4 from a first position P1, in which the limbs 4 enclose a first angle 1 together with the shaft 3, into a second position P2, in which the limbs 4 enclose a second angle 2 together with the shaft 3.
(13) The positions P1 and P2 as well as the first angle 1 and the second angle 2 are to be seen in particular in the detail views in FIGS. 2 and 2A, which show an enlarged view of detail D in FIG. 1. The first position P1 corresponds to a relaxed position of the limbs 4, in which the bowstring 8 connected to the limbs 4 can be fixed quickly and without a great deal of effort by the shooter in a triggering device 19 arranged on the shaft 3. By contrast the second position P2 corresponds to a tensioned position of the limbs 4, wherein the bowstring 8 is also tensioned. Accordingly the second angle 2 is larger than the first angle 1. For better understanding a relaxed position P1 of the left limb 4 is shown in FIG. 2 as a broken line. FIG. 2A, also for the purpose of better understanding, shows a left limb 4 in the first position P1 and a right limb 4 in the second position P2. In fact the tensioning device 1 is designed to pivot both limbs 4 symmetrically to the shaft 3.
(14) In FIGS. 1, 2 and 2A each of the drive devices 7 comprises a lifting device 9 with a hydraulically, electrically or pneumatically displaceable reciprocating piston 10. The reciprocating piston 10 can be moved out of the lifting device 9 as shown in the right-hand part of FIG. 2A and can be moved back into the lifting device 9, as depicted in the left-hand part of FIG. 2A. In particular each lifting device 9/each reciprocating piston 10 is arranged at an acute angle relative to an imagined extension V of the shaft 3, so that the pins B2 or their axes of rotation A2 are arranged particularly close to the pins B1/their axes of rotation A1 on the securing devices 6. In this way a small change in lift, which is defined as the difference between the lift H1 of the retracted reciprocating piston 10 and the lift H2 of the extended reciprocating piston 10, can cause a large difference between angle 1 and angle 2. The crossbow 2 can thus be tensioned in a particularly quick manner. The acute angle is preferably smaller than 60, in particular smaller than 45. The distance X between the pins B1 and B2/between axes of rotation A1 and A2 may be smaller than the change in lift (H2H1).
(15) FIGS. 3 to 6 show four different states of the crossbow 2. In FIG. 3 the crossbow 2 is depicted directly following firing a shot, wherein the limbs 4 and the bowstring 8 are still tensioned, i.e. the limbs 4 are still in the second tensioned position P2. FIG. 4 shows the crossbow 2 after firing a shot with limbs 4 already partially pivoted, so that these and the bowstring 8 are relaxed. In FIG. 5 the crossbow 2 is depicted after firing a shot with relaxed limbs 4 and a relaxed bowstring 8, wherein the bowstring 8 is already in engagement with a triggering device 19 designed in a manner known as such, in order to mechanically fix or release the bowstring 8. In this state the limbs 4 are pivoted into the first position P1. FIG. 6 finally shows the crossbow 2 in a tensioned state prior to firing a shot, i.e. the bowstring 8 is still fixed by the triggering device 19 and the limbs 4 are again pivoted into the second position 2.
(16) FIG. 7 shows a crossbow 2 in a perspective view with a deactivation device 11, for deactivating the drive device 7, in order to thereby cancel the force exerted by the drive device 7 upon the limbs 4 and to rotate the still temporarily tensioned limbs 4 automatically in direction of the first position P1/into the first position P1. The deactivation device 11 is triggered either by the limbs 4 or the bowstring 8 at the end of firing a shot, or by the shooter by means of a manual actuating element 11a. The deactivation device 11 for example comprises an actuating element 12 for relieving pressure on the hydraulically, electrically or pneumatically driven lifting device 9, which actuating element 12 is hit by the bowstring 8 at the end of firing a shot. The actuating element 12 may be realised by a valve, which may be provided for relieving pressure from a pneumatically driven lifting device 9. Also depicted in FIG. 7 is an integrated or replaceable compressed air container 16 or store for electrical energy 17 for supplying the drive device 7 depicted as a shoulder support 18 with energy, as well as a sound absorber 14 on the drive device 7. FIG. 7 also shows a safety element 15 which is connected to the drive device 7 via a safety device 15b The safety device 15b is designed to mechanically fix/release the bowstring 8 in/from the triggering device 19 and to activate or deactivate the drive device 7. A magazine 22 for projectiles G, in particular for arrows G1 or roundballs R, is arranged on the shaft 3.
(17) FIGS. 8A to 8C show the safety element 15 in three different positions, wherein in the deactivation position S1 of safety element 15 depicted in FIG. 8A, the drive device 7 is deactivated by the safety device 15b, in the safety position S2 of the safety element 15 depicted in FIG. 8B, the drive device 7 is activated by the safety device 15b and the bowstring 8 is fixed in the triggering device 19, and wherein in the release position S3 of the safety element 15 depicted in FIG. 8C the drive device 7 is still activated by the safety device 15b and the bowstring 8 is released by the triggering device 19 for firing a shot.
(18) FIG. 9 shows a schematic sectional view of a tensioning device 1 for a crossbow 2, with a return spring 13 as part of the drive device 7 for automatically returning the reciprocating piston 10/the limbs 4 (not shown) mounted via the securing device 6 in direction of the first position P1/into the first position P1. Moreover fluid channels 20 connected to the drive device 7, in particular to the lifting device 9 are provided for supplying and discharging compressed air or a hydraulic liquid. Furthermore provision is made for a compressed-air container 16 and a shuttle valve 21, which functions as a drain valve and an inlet valve. The drive device 7 can be deactivated via the deactivation device 11 at the end of firing a shot. As schematically shown a sound absorber 14 may be provided. In the case of an electrically driven drive device 7 a store for electrical energy 17, in particular a battery (not shown) may be provided instead of the compressed-air container 16.
